oxedyne/fe2o3/fe2o3_text/tests/annealer_corpus/tracing_span.rs
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| 1 | //! Spans represent periods of time in which a program was executing in a |
| 2 | //! particular context. |
| 3 | //! |
| 4 | //! A span consists of [fields], user-defined key-value pairs of arbitrary data |
| 5 | //! that describe the context the span represents, and a set of fixed attributes |
| 6 | //! that describe all `tracing` spans and events. Attributes describing spans |
| 7 | //! include: |
| 8 | //! |
| 9 | //! - An [`Id`] assigned by the subscriber that uniquely identifies it in relation |
| 10 | //! to other spans. |
| 11 | //! - The span's [parent] in the trace tree. |
| 12 | //! - [Metadata] that describes static characteristics of all spans |
| 13 | //! originating from that callsite, such as its name, source code location, |
| 14 | //! [verbosity level], and the names of its fields. |
| 15 | //! |
| 16 | //! # Creating Spans |
| 17 | //! |
| 18 | //! Spans are created using the [`span!`] macro. This macro is invoked with the |
| 19 | //! following arguments, in order: |
| 20 | //! |
| 21 | //! - The [`target`] and/or [`parent`][parent] attributes, if the user wishes to |
| 22 | //! override their default values. |
| 23 | //! - The span's [verbosity level] |
| 24 | //! - A string literal providing the span's name. |
| 25 | //! - Finally, zero or more arbitrary key/value fields. |
| 26 | //! |
| 27 | //! [`target`]: super::Metadata::target() |
| 28 | //! |
| 29 | //! For example: |
| 30 | //! ```rust |
| 31 | //! use tracing::{span, Level}; |
| 32 | //! |
| 33 | //! /// Construct a new span at the `INFO` level named "my_span", with a single |
| 34 | //! /// field named answer , with the value `42`. |
| 35 | //! let my_span = span!(Level::INFO, "my_span", answer = 42); |
| 36 | //! ``` |
| 37 | //! |
| 38 | //! The documentation for the [`span!`] macro provides additional examples of |
| 39 | //! the various options that exist when creating spans. |
| 40 | //! |
| 41 | //! The [`trace_span!`], [`debug_span!`], [`info_span!`], [`warn_span!`], and |
| 42 | //! [`error_span!`] exist as shorthand for constructing spans at various |
| 43 | //! verbosity levels. |
| 44 | //! |
| 45 | //! ## Recording Span Creation |
| 46 | //! |
| 47 | //! The [`Attributes`] type contains data associated with a span, and is |
| 48 | //! provided to the [collector] when a new span is created. It contains |
| 49 | //! the span's metadata, the ID of [the span's parent][parent] if one was |
| 50 | //! explicitly set, and any fields whose values were recorded when the span was |
| 51 | //! constructed. The collector, which is responsible for recording `tracing` |
| 52 | //! data, can then store or record these values. |
| 53 | //! |
| 54 | //! # The Span Lifecycle |
| 55 | //! |
| 56 | //! ## Entering a Span |
| 57 | //! |
| 58 | //! A thread of execution is said to _enter_ a span when it begins executing, |
| 59 | //! and _exit_ the span when it switches to another context. Spans may be |
| 60 | //! entered through the [`enter`] and [`in_scope`] methods. |
| 61 | //! |
| 62 | //! The `enter` method enters a span, returning a [guard] that exits the span |
| 63 | //! when dropped |
| 64 | //! ``` |
| 65 | //! # use tracing::{Level, span}; |
| 66 | //! let my_var: u64 = 5; |
| 67 | //! let my_span = span!(Level::TRACE, "my_span", my_var); |
| 68 | //! |
| 69 | //! // `my_span` exists but has not been entered. |
| 70 | //! |
| 71 | //! // Enter `my_span`... |
| 72 | //! let _enter = my_span.enter(); |
| 73 | //! |
| 74 | //! // Perform some work inside of the context of `my_span`... |
| 75 | //! // Dropping the `_enter` guard will exit the span. |
| 76 | //!``` |
| 77 | //! |
| 78 | //! <div class="example-wrap" style="display:inline-block"><pre class="compile_fail" style="white-space:normal;font:inherit;"> |
| 79 | //! |
| 80 | //! **Warning**: In asynchronous code that uses async/await syntax, |
| 81 | //! [`Span::enter`] may produce incorrect traces if the returned drop |
| 82 | //! guard is held across an await point. See |
| 83 | //! [the method documentation][Span#in-asynchronous-code] for details. |
| 84 | //! |
| 85 | //! </pre></div> |
| 86 | //! |
| 87 | //! `in_scope` takes a closure or function pointer and executes it inside the |
| 88 | //! span. |
| 89 | //! ``` |
| 90 | //! # use tracing::{Level, span}; |
| 91 | //! let my_var: u64 = 5; |
| 92 | //! let my_span = span!(Level::TRACE, "my_span", my_var = &my_var); |
| 93 | //! |
| 94 | //! my_span.in_scope(|| { |
| 95 | //! // perform some work in the context of `my_span`... |
| 96 | //! }); |
| 97 | //! |
| 98 | //! // Perform some work outside of the context of `my_span`... |
| 99 | //! |
| 100 | //! my_span.in_scope(|| { |
| 101 | //! // Perform some more work in the context of `my_span`. |
| 102 | //! }); |
| 103 | //! ``` |
| 104 | //! |
| 105 | //! <div class="example-wrap" style="display:inline-block"> |
| 106 | //! <pre class="ignore" style="white-space:normal;font:inherit;"> |
| 107 | //! <strong>Note</strong>: Since entering a span takes <code>&self</code>, and |
| 108 | //! <code>Span</code>s are <code>Clone</code>, <code>Send</code>, and |
| 109 | //! <code>Sync</code>, it is entirely valid for multiple threads to enter the |
| 110 | //! same span concurrently. |
| 111 | //! </pre></div> |
| 112 | //! |
| 113 | //! ## Span Relationships |
| 114 | //! |
| 115 | //! Spans form a tree structure — unless it is a root span, all spans have a |
| 116 | //! _parent_, and may have one or more _children_. When a new span is created, |
| 117 | //! the current span becomes the new span's parent. The total execution time of |
| 118 | //! a span consists of the time spent in that span and in the entire subtree |
| 119 | //! represented by its children. Thus, a parent span always lasts for at least |
| 120 | //! as long as the longest-executing span in its subtree. |
| 121 | //! |
| 122 | //! ``` |
| 123 | //! # use tracing::{Level, span}; |
| 124 | //! // this span is considered the "root" of a new trace tree: |
| 125 | //! span!(Level::INFO, "root").in_scope(|| { |
| 126 | //! // since we are now inside "root", this span is considered a child |
| 127 | //! // of "root": |
| 128 | //! span!(Level::DEBUG, "outer_child").in_scope(|| { |
| 129 | //! // this span is a child of "outer_child", which is in turn a |
| 130 | //! // child of "root": |
| 131 | //! span!(Level::TRACE, "inner_child").in_scope(|| { |
| 132 | //! // and so on... |
| 133 | //! }); |
| 134 | //! }); |
| 135 | //! // another span created here would also be a child of "root". |
| 136 | //! }); |
| 137 | //!``` |
| 138 | //! |
| 139 | //! In addition, the parent of a span may be explicitly specified in |
| 140 | //! the `span!` macro. For example: |
| 141 | //! |
| 142 | //! ```rust |
| 143 | //! # use tracing::{Level, span}; |
| 144 | //! // Create, but do not enter, a span called "foo". |
| 145 | //! let foo = span!(Level::INFO, "foo"); |
| 146 | //! |
| 147 | //! // Create and enter a span called "bar". |
| 148 | //! let bar = span!(Level::INFO, "bar"); |
| 149 | //! let _enter = bar.enter(); |
| 150 | //! |
| 151 | //! // Although we have currently entered "bar", "baz"'s parent span |
| 152 | //! // will be "foo". |
| 153 | //! let baz = span!(parent: &foo, Level::INFO, "baz"); |
| 154 | //! ``` |
| 155 | //! |
| 156 | //! A child span should typically be considered _part_ of its parent. For |
| 157 | //! example, if a collector is recording the length of time spent in various |
| 158 | //! spans, it should generally include the time spent in a span's children as |
| 159 | //! part of that span's duration. |
| 160 | //! |
| 161 | //! In addition to having zero or one parent, a span may also _follow from_ any |
| 162 | //! number of other spans. This indicates a causal relationship between the span |
| 163 | //! and the spans that it follows from, but a follower is *not* typically |
| 164 | //! considered part of the duration of the span it follows. Unlike the parent, a |
| 165 | //! span may record that it follows from another span after it is created, using |
| 166 | //! the [`follows_from`] method. |
| 167 | //! |
| 168 | //! As an example, consider a listener task in a server. As the listener accepts |
| 169 | //! incoming connections, it spawns new tasks that handle those connections. We |
| 170 | //! might want to have a span representing the listener, and instrument each |
| 171 | //! spawned handler task with its own span. We would want our instrumentation to |
| 172 | //! record that the handler tasks were spawned as a result of the listener task. |
| 173 | //! However, we might not consider the handler tasks to be _part_ of the time |
| 174 | //! spent in the listener task, so we would not consider those spans children of |
| 175 | //! the listener span. Instead, we would record that the handler tasks follow |
| 176 | //! from the listener, recording the causal relationship but treating the spans |
| 177 | //! as separate durations. |
| 178 | //! |
| 179 | //! ## Closing Spans |
| 180 | //! |
| 181 | //! Execution may enter and exit a span multiple times before that span is |
| 182 | //! _closed_. Consider, for example, a future which has an associated |
| 183 | //! span and enters that span every time it is polled: |
| 184 | //! ```rust |
| 185 | //! # use std::future::Future; |
| 186 | //! # use std::task::{Context, Poll}; |
| 187 | //! # use std::pin::Pin; |
| 188 | //! struct MyFuture { |
| 189 | //! // data |
| 190 | //! span: tracing::Span, |
| 191 | //! } |
| 192 | //! |
| 193 | //! impl Future for MyFuture { |
| 194 | //! type Output = (); |
| 195 | //! |
| 196 | //! fn poll(self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<Self::Output> { |
| 197 | //! let _enter = self.span.enter(); |
| 198 | //! // Do actual future work... |
| 199 | //! # Poll::Ready(()) |
| 200 | //! } |
| 201 | //! } |
| 202 | //! ``` |
| 203 | //! |
| 204 | //! If this future was spawned on an executor, it might yield one or more times |
| 205 | //! before `poll` returns [`Poll::Ready`]. If the future were to yield, then |
| 206 | //! the executor would move on to poll the next future, which may _also_ enter |
| 207 | //! an associated span or series of spans. Therefore, it is valid for a span to |
| 208 | //! be entered repeatedly before it completes. Only the time when that span or |
| 209 | //! one of its children was the current span is considered to be time spent in |
| 210 | //! that span. A span which is not executing and has not yet been closed is said |
| 211 | //! to be _idle_. |
| 212 | //! |
| 213 | //! Because spans may be entered and exited multiple times before they close, |
| 214 | //! [collector]s have separate trait methods which are called to notify them |
| 215 | //! of span exits and when span handles are dropped. When execution exits a |
| 216 | //! span, [`exit`] will always be called with that span's ID to notify the |
| 217 | //! collector that the span has been exited. When span handles are dropped, the |
| 218 | //! [`drop_span`] method is called with that span's ID. The collector may use |
| 219 | //! this to determine whether or not the span will be entered again. |
| 220 | //! |
| 221 | //! If there is only a single handle with the capacity to exit a span, dropping |
| 222 | //! that handle "closes" the span, since the capacity to enter it no longer |
| 223 | //! exists. For example: |
| 224 | //! ``` |
| 225 | //! # use tracing::{Level, span}; |
| 226 | //! { |
| 227 | //! span!(Level::TRACE, "my_span").in_scope(|| { |
| 228 | //! // perform some work in the context of `my_span`... |
| 229 | //! }); // --> Collect::exit(my_span) |
| 230 | //! |
| 231 | //! // The handle to `my_span` only lives inside of this block; when it is |
| 232 | //! // dropped, the collector will be informed via `drop_span`. |
| 233 | //! |
| 234 | //! } // --> Collect::drop_span(my_span) |
| 235 | //! ``` |
| 236 | //! |
| 237 | //! However, if multiple handles exist, the span can still be re-entered even if |
| 238 | //! one or more is dropped. For determining when _all_ handles to a span have |
| 239 | //! been dropped, collectors have a [`clone_span`] method, which is called |
| 240 | //! every time a span handle is cloned. Combined with `drop_span`, this may be |
| 241 | //! used to track the number of handles to a given span — if `drop_span` has |
| 242 | //! been called one more time than the number of calls to `clone_span` for a |
| 243 | //! given ID, then no more handles to the span with that ID exist. The |
| 244 | //! collector may then treat it as closed. |
| 245 | //! |
| 246 | //! # When to use spans |
| 247 | //! |
| 248 | //! As a rule of thumb, spans should be used to represent discrete units of work |
| 249 | //! (e.g., a given request's lifetime in a server) or periods of time spent in a |
| 250 | //! given context (e.g., time spent interacting with an instance of an external |
| 251 | //! system, such as a database). |
| 252 | //! |
| 253 | //! Which scopes in a program correspond to new spans depend somewhat on user |
| 254 | //! intent. For example, consider the case of a loop in a program. Should we |
| 255 | //! construct one span and perform the entire loop inside of that span, like: |
| 256 | //! |
| 257 | //! ```rust |
| 258 | //! # use tracing::{Level, span}; |
| 259 | //! # let n = 1; |
| 260 | //! let span = span!(Level::TRACE, "my_loop"); |
| 261 | //! let _enter = span.enter(); |
| 262 | //! for i in 0..n { |
| 263 | //! # let _ = i; |
| 264 | //! // ... |
| 265 | //! } |
| 266 | //! ``` |
| 267 | //! Or, should we create a new span for each iteration of the loop, as in: |
| 268 | //! ```rust |
| 269 | //! # use tracing::{Level, span}; |
| 270 | //! # let n = 1u64; |
| 271 | //! for i in 0..n { |
| 272 | //! let span = span!(Level::TRACE, "my_loop", iteration = i); |
| 273 | //! let _enter = span.enter(); |
| 274 | //! // ... |
| 275 | //! } |
| 276 | //! ``` |
| 277 | //! |
| 278 | //! Depending on the circumstances, we might want to do either, or both. For |
| 279 | //! example, if we want to know how long was spent in the loop overall, we would |
| 280 | //! create a single span around the entire loop; whereas if we wanted to know how |
| 281 | //! much time was spent in each individual iteration, we would enter a new span |
| 282 | //! on every iteration. |
| 283 | //! |
| 284 | //! [fields]: super::field |
| 285 | //! [Metadata]: super::Metadata |
| 286 | //! [verbosity level]: super::Level |
| 287 | //! [`Poll::Ready`]: std::task::Poll::Ready |
| 288 | //! [`span!`]: super::span! |
| 289 | //! [`trace_span!`]: super::trace_span! |
| 290 | //! [`debug_span!`]: super::debug_span! |
| 291 | //! [`info_span!`]: super::info_span! |
| 292 | //! [`warn_span!`]: super::warn_span! |
| 293 | //! [`error_span!`]: super::error_span! |
| 294 | //! [`clone_span`]: super::collect::Collect::clone_span() |
| 295 | //! [`drop_span`]: super::collect::Collect::drop_span() |
| 296 | //! [`exit`]: super::collect::Collect::exit |
| 297 | //! [collector]: super::collect::Collect |
| 298 | //! [`enter`]: Span::enter() |
| 299 | //! [`in_scope`]: Span::in_scope() |
| 300 | //! [`follows_from`]: Span::follows_from() |
| 301 | //! [guard]: Entered |
| 302 | //! [parent]: #span-relationships |
| 303 | pub use tracing_core::span::{Attributes, Id, Record}; |
| 304 | |
| 305 | use crate::{ |
| 306 | dispatch::{self, Dispatch}, |
| 307 | field, Metadata, |
| 308 | }; |
| 309 | use core::{ |
| 310 | cmp, fmt, |
| 311 | hash::{Hash, Hasher}, |
| 312 | marker::PhantomData, |
| 313 | mem, |
| 314 | ops::Deref, |
| 315 | }; |
| 316 | |
| 317 | /// Trait implemented by types which have a span `Id`. |
| 318 | pub trait AsId: crate::sealed::Sealed { |
| 319 | /// Returns the `Id` of the span that `self` corresponds to, or `None` if |
| 320 | /// this corresponds to a disabled span. |
| 321 | fn as_id(&self) -> Option<&Id>; |
| 322 | } |
| 323 | |
| 324 | /// A handle representing a span, with the capability to enter the span if it |
| 325 | /// exists. |
| 326 | /// |
| 327 | /// If the span was rejected by the current `Collector`'s filter, entering the |
| 328 | /// span will silently do nothing. Thus, the handle can be used in the same |
| 329 | /// manner regardless of whether or not the trace is currently being collected. |
| 330 | #[derive(Clone)] |
| 331 | pub struct Span { |
| 332 | /// A handle used to enter the span when it is not executing. |
| 333 | /// |
| 334 | /// If this is `None`, then the span has either closed or was never enabled. |
| 335 | inner: Option<Inner>, |
| 336 | /// Metadata describing the span. |
| 337 | /// |
| 338 | /// This might be `Some` even if `inner` is `None`, in the case that the |
| 339 | /// span is disabled but the metadata is needed for `log` support. |
| 340 | meta: Option<&'static Metadata<'static>>, |
| 341 | } |
| 342 | |
| 343 | /// A handle representing the capacity to enter a span which is known to exist. |
| 344 | /// |
| 345 | /// Unlike `Span`, this type is only constructed for spans which _have_ been |
| 346 | /// enabled by the current filter. This type is primarily used for implementing |
| 347 | /// span handles; users should typically not need to interact with it directly. |
| 348 | #[derive(Debug)] |
| 349 | pub(crate) struct Inner { |
| 350 | /// The span's ID, as provided by `collector`. |
| 351 | id: Id, |
| 352 | |
| 353 | /// The collector that will receive events relating to this span. |
| 354 | /// |
| 355 | /// This should be the same collector that provided this span with its |
| 356 | /// `id`. |
| 357 | collector: Dispatch, |
| 358 | } |
| 359 | |
| 360 | /// A guard representing a span which has been entered and is currently |
| 361 | /// executing. |
| 362 | /// |
| 363 | /// When the guard is dropped, the span will be exited. |
| 364 | /// |
| 365 | /// This is returned by the [`Span::enter`] function. |
| 366 | /// |
| 367 | /// [`Span::enter`]: super::Span::enter() |
| 368 | #[derive(Debug)] |
| 369 | #[must_use = "once a span has been entered, it should be exited"] |
| 370 | pub struct Entered<'a> { |
| 371 | span: &'a Span, |
| 372 | |
| 373 | /// ```compile_fail |
| 374 | /// use tracing::span::*; |
| 375 | /// trait AssertSend: Send {} |
| 376 | /// |
| 377 | /// impl AssertSend for Entered<'_> {} |
| 378 | /// ``` |
| 379 | _not_send: PhantomNotSend, |
| 380 | } |
| 381 | |
| 382 | /// An owned version of [`Entered`], a guard representing a span which has been |
| 383 | /// entered and is currently executing. |
| 384 | /// |
| 385 | /// When the guard is dropped, the span will be exited. |
| 386 | /// |
| 387 | /// This is returned by the [`Span::entered`] function. |
| 388 | /// |
| 389 | /// [`Span::entered`]: super::Span::entered() |
| 390 | #[derive(Debug)] |
| 391 | #[must_use = "once a span has been entered, it should be exited"] |
| 392 | pub struct EnteredSpan { |
| 393 | span: Span, |
| 394 | |
| 395 | /// ```compile_fail |
| 396 | /// use tracing::span::*; |
| 397 | /// trait AssertSend: Send {} |
| 398 | /// |
| 399 | /// impl AssertSend for EnteredSpan {} |
| 400 | /// ``` |
| 401 | _not_send: PhantomNotSend, |
| 402 | } |
| 403 | |
| 404 | /// `log` target for all span lifecycle (creation/enter/exit/close) records. |
| 405 | #[cfg(feature = "log")] |
| 406 | const LIFECYCLE_LOG_TARGET: &str = "tracing::span"; |
| 407 | /// `log` target for span activity (enter/exit) records. |
| 408 | #[cfg(feature = "log")] |
| 409 | const ACTIVITY_LOG_TARGET: &str = "tracing::span::active"; |
| 410 | |
| 411 | // ===== impl Span ===== |
| 412 | |
| 413 | impl Span { |
| 414 | /// Constructs a new `Span` with the given [metadata] and set of |
| 415 | /// [field values]. |
| 416 | /// |
| 417 | /// The new span will be constructed by the currently-active [collector], |
| 418 | /// with the current span as its parent (if one exists). |
| 419 | /// |
| 420 | /// After the span is constructed, [field values] and/or [`follows_from`] |
| 421 | /// annotations may be added to it. |
| 422 | /// |
| 423 | /// [metadata]: mod@super::metadata |
| 424 | /// [collector]: super::collect::Collect |
| 425 | /// [field values]: super::field::ValueSet |
| 426 | /// [`follows_from`]: super::Span::follows_from() |
| 427 | pub fn new(meta: &'static Metadata<'static>, values: &field::ValueSet<'_>) -> Span { |
| 428 | dispatch::get_default(|dispatch| Self::new_with(meta, values, dispatch)) |
| 429 | } |
| 430 | |
| 431 | #[inline] |
| 432 | #[doc(hidden)] |
| 433 | pub fn new_with( |
| 434 | meta: &'static Metadata<'static>, |
| 435 | values: &field::ValueSet<'_>, |
| 436 | dispatch: &Dispatch, |
| 437 | ) -> Span { |
| 438 | let new_span = Attributes::new(meta, values); |
| 439 | Self::make_with(meta, new_span, dispatch) |
| 440 | } |
| 441 | |
| 442 | /// Constructs a new `Span` as the root of its own trace tree, with the |
| 443 | /// given [metadata] and set of [field values]. |
| 444 | /// |
| 445 | /// After the span is constructed, [field values] and/or [`follows_from`] |
| 446 | /// annotations may be added to it. |
| 447 | /// |
| 448 | /// [metadata]: mod@super::metadata |
| 449 | /// [field values]: super::field::ValueSet |
| 450 | /// [`follows_from`]: super::Span::follows_from() |
| 451 | pub fn new_root(meta: &'static Metadata<'static>, values: &field::ValueSet<'_>) -> Span { |
| 452 | dispatch::get_default(|dispatch| Self::new_root_with(meta, values, dispatch)) |
| 453 | } |
| 454 | |
| 455 | #[inline] |
| 456 | #[doc(hidden)] |
| 457 | pub fn new_root_with( |
| 458 | meta: &'static Metadata<'static>, |
| 459 | values: &field::ValueSet<'_>, |
| 460 | dispatch: &Dispatch, |
| 461 | ) -> Span { |
| 462 | let new_span = Attributes::new_root(meta, values); |
| 463 | Self::make_with(meta, new_span, dispatch) |
| 464 | } |
| 465 | |
| 466 | /// Constructs a new `Span` as child of the given parent span, with the |
| 467 | /// given [metadata] and set of [field values]. |
| 468 | /// |
| 469 | /// After the span is constructed, [field values] and/or [`follows_from`] |
| 470 | /// annotations may be added to it. |
| 471 | /// |
| 472 | /// [metadata]: mod@super::metadata |
| 473 | /// [field values]: super::field::ValueSet |
| 474 | /// [`follows_from`]: super::Span::follows_from() |
| 475 | pub fn child_of( |
| 476 | parent: impl Into<Option<Id>>, |
| 477 | meta: &'static Metadata<'static>, |
| 478 | values: &field::ValueSet<'_>, |
| 479 | ) -> Span { |
| 480 | let mut parent = parent.into(); |
| 481 | dispatch::get_default(move |dispatch| { |
| 482 | Self::child_of_with(Option::take(&mut parent), meta, values, dispatch) |
| 483 | }) |
| 484 | } |
| 485 | |
| 486 | #[inline] |
| 487 | #[doc(hidden)] |
| 488 | pub fn child_of_with( |
| 489 | parent: impl Into<Option<Id>>, |
| 490 | meta: &'static Metadata<'static>, |
| 491 | values: &field::ValueSet<'_>, |
| 492 | dispatch: &Dispatch, |
| 493 | ) -> Span { |
| 494 | let new_span = match parent.into() { |
| 495 | Some(parent) => Attributes::child_of(parent, meta, values), |
| 496 | None => Attributes::new_root(meta, values), |
| 497 | }; |
| 498 | Self::make_with(meta, new_span, dispatch) |
| 499 | } |
| 500 | |
| 501 | /// Constructs a new disabled span with the given `Metadata`. |
| 502 | /// |
| 503 | /// This should be used when a span is constructed from a known callsite, |
| 504 | /// but the collector indicates that it is disabled. |
| 505 | /// |
| 506 | /// Entering, exiting, and recording values on this span will not notify the |
| 507 | /// `Collector` but _may_ record log messages if the `log` feature flag is |
| 508 | /// enabled. |
| 509 | #[inline(always)] |
| 510 | pub fn new_disabled(meta: &'static Metadata<'static>) -> Span { |
| 511 | Self { |
| 512 | inner: None, |
| 513 | meta: Some(meta), |
| 514 | } |
| 515 | } |
| 516 | |
| 517 | /// Constructs a new span that is *completely disabled*. |
| 518 | /// |
| 519 | /// This can be used rather than `Option<Span>` to represent cases where a |
| 520 | /// span is not present. |
| 521 | /// |
| 522 | /// Entering, exiting, and recording values on this span will do nothing. |
| 523 | #[inline(always)] |
| 524 | pub const fn none() -> Span { |
| 525 | Self { |
| 526 | inner: None, |
| 527 | meta: None, |
| 528 | } |
| 529 | } |
| 530 | |
| 531 | /// Returns a handle to the span [considered by the `Collector`] to be the |
| 532 | /// current span. |
| 533 | /// |
| 534 | /// If the collector indicates that it does not track the current span, or |
| 535 | /// that the thread from which this function is called is not currently |
| 536 | /// inside a span, the returned span will be disabled. |
| 537 | /// |
| 538 | /// [considered by the `Collector`]: super::collect::Collect::current_span() |
| 539 | pub fn current() -> Span { |
| 540 | dispatch::get_default(|dispatch| { |
| 541 | if let Some((id, meta)) = dispatch.current_span().into_inner() { |
| 542 | let id = dispatch.clone_span(&id); |
| 543 | Self { |
| 544 | inner: Some(Inner::new(id, dispatch)), |
| 545 | meta: Some(meta), |
| 546 | } |
| 547 | } else { |
| 548 | Self::none() |
| 549 | } |
| 550 | }) |
| 551 | } |
| 552 | |
| 553 | fn make_with( |
| 554 | meta: &'static Metadata<'static>, |
| 555 | new_span: Attributes<'_>, |
| 556 | dispatch: &Dispatch, |
| 557 | ) -> Span { |
| 558 | let attrs = &new_span; |
| 559 | let id = dispatch.new_span(attrs); |
| 560 | let inner = Some(Inner::new(id, dispatch)); |
| 561 | |
| 562 | let span = Self { |
| 563 | inner, |
| 564 | meta: Some(meta), |
| 565 | }; |
| 566 | |
| 567 | if_log_enabled! { *meta.level(), { |
| 568 | let target = if attrs.is_empty() { |
| 569 | LIFECYCLE_LOG_TARGET |
| 570 | } else { |
| 571 | meta.target() |
| 572 | }; |
| 573 | let values = attrs.values(); |
| 574 | span.log( |
| 575 | target, |
| 576 | level_to_log!(*meta.level()), |
| 577 | format_args!("++ {};{}", meta.name(), crate::log::LogValueSet { values, is_first: false }), |
| 578 | ); |
| 579 | }} |
| 580 | |
| 581 | span |
| 582 | } |
| 583 | |
| 584 | /// Enters this span, returning a guard that will exit the span when dropped. |
| 585 | /// |
| 586 | /// If this span is enabled by the current collector, then this function will |
| 587 | /// call [`Collect::enter`] with the span's [`Id`], and dropping the guard |
| 588 | /// will call [`Collect::exit`]. If the span is disabled, this does |
| 589 | /// nothing. |
| 590 | /// |
| 591 | /// <div class="example-wrap" style="display:inline-block"> |
| 592 | /// <pre class="ignore" style="white-space:normal;font:inherit;"> |
| 593 | /// |
| 594 | /// **Note**: The returned [`Entered`] guard does not |
| 595 | /// implement `Send`. Dropping the guard will exit *this* span, |
| 596 | /// and if the guard is sent to another thread and dropped there, that thread may |
| 597 | /// never have entered this span. Thus, `Entered` should not be sent |
| 598 | /// between threads. |
| 599 | /// |
| 600 | /// </pre></div> |
| 601 | /// |
| 602 | /// **Warning**: in asynchronous code that uses [async/await syntax][syntax], |
| 603 | /// [`Span::enter`] should be used very carefully or avoided entirely. Holding |
| 604 | /// the drop guard returned by `Span::enter` across `.await` points will |
| 605 | /// result in incorrect traces. For example, |
| 606 | /// |
| 607 | /// ``` |
| 608 | /// # use tracing::info_span; |
| 609 | /// # async fn some_other_async_function() {} |
| 610 | /// async fn my_async_function() { |
| 611 | /// let span = info_span!("my_async_function"); |
| 612 | /// |
| 613 | /// // WARNING: This span will remain entered until this |
| 614 | /// // guard is dropped... |
| 615 | /// let _enter = span.enter(); |
| 616 | /// // ...but the `await` keyword may yield, causing the |
| 617 | /// // runtime to switch to another task, while remaining in |
| 618 | /// // this span! |
| 619 | /// some_other_async_function().await |
| 620 | /// |
| 621 | /// // ... |
| 622 | /// } |
| 623 | /// ``` |
| 624 | /// |
| 625 | /// The drop guard returned by `Span::enter` exits the span when it is |
| 626 | /// dropped. When an async function or async block yields at an `.await` |
| 627 | /// point, the current scope is _exited_, but values in that scope are |
| 628 | /// **not** dropped (because the async block will eventually resume |
| 629 | /// execution from that await point). This means that _another_ task will |
| 630 | /// begin executing while _remaining_ in the entered span. This results in |
| 631 | /// an incorrect trace. |
| 632 | /// |
| 633 | /// Instead of using `Span::enter` in asynchronous code, prefer the |
| 634 | /// following: |
| 635 | /// |
| 636 | /// * To enter a span for a synchronous section of code within an async |
| 637 | /// block or function, prefer [`Span::in_scope`]. Since `in_scope` takes a |
| 638 | /// synchronous closure and exits the span when the closure returns, the |
| 639 | /// span will always be exited before the next await point. For example: |
| 640 | /// ``` |
| 641 | /// # use tracing::info_span; |
| 642 | /// # async fn some_other_async_function(_: ()) {} |
| 643 | /// async fn my_async_function() { |
| 644 | /// let span = info_span!("my_async_function"); |
| 645 | /// |
| 646 | /// let some_value = span.in_scope(|| { |
| 647 | /// // run some synchronous code inside the span... |
| 648 | /// }); |
| 649 | /// |
| 650 | /// // This is okay! The span has already been exited before we reach |
| 651 | /// // the await point. |
| 652 | /// some_other_async_function(some_value).await; |
| 653 | /// |
| 654 | /// // ... |
| 655 | /// } |
| 656 | /// ``` |
| 657 | /// * For instrumenting asynchronous code, `tracing` provides the |
| 658 | /// [`Future::instrument` combinator][instrument] for |
| 659 | /// attaching a span to a future (async function or block). This will |
| 660 | /// enter the span _every_ time the future is polled, and exit it whenever |
| 661 | /// the future yields. |
| 662 | /// |
| 663 | /// `Instrument` can be used with an async block inside an async function: |
| 664 | /// ```ignore |
| 665 | /// # use tracing::info_span; |
| 666 | /// use tracing::Instrument; |
| 667 | /// |
| 668 | /// # async fn some_other_async_function() {} |
| 669 | /// async fn my_async_function() { |
| 670 | /// let span = info_span!("my_async_function"); |
| 671 | /// async move { |
| 672 | /// // This is correct! If we yield here, the span will be exited, |
| 673 | /// // and re-entered when we resume. |
| 674 | /// some_other_async_function().await; |
| 675 | /// |
| 676 | /// //more asynchronous code inside the span... |
| 677 | /// |
| 678 | /// } |
| 679 | /// // instrument the async block with the span... |
| 680 | /// .instrument(span) |
| 681 | /// // ...and await it. |
| 682 | /// .await |
| 683 | /// } |
| 684 | /// ``` |
| 685 | /// |
| 686 | /// It can also be used to instrument calls to async functions at the |
| 687 | /// callsite: |
| 688 | /// ```ignore |
| 689 | /// # use tracing::debug_span; |
| 690 | /// use tracing::Instrument; |
| 691 | /// |
| 692 | /// # async fn some_other_async_function() {} |
| 693 | /// async fn my_async_function() { |
| 694 | /// let some_value = some_other_async_function() |
| 695 | /// .instrument(debug_span!("some_other_async_function")) |
| 696 | /// .await; |
| 697 | /// |
| 698 | /// // ... |
| 699 | /// } |
| 700 | /// ``` |
| 701 | /// |
| 702 | /// * The [`#[instrument]` attribute macro][attr] can automatically generate |
| 703 | /// correct code when used on an async function: |
| 704 | /// |
| 705 | /// ```ignore |
| 706 | /// # async fn some_other_async_function() {} |
| 707 | /// #[tracing::instrument(level = "info")] |
| 708 | /// async fn my_async_function() { |
| 709 | /// |
| 710 | /// // This is correct! If we yield here, the span will be exited, |
| 711 | /// // and re-entered when we resume. |
| 712 | /// some_other_async_function().await; |
| 713 | /// |
| 714 | /// // ... |
| 715 | /// |
| 716 | /// } |
| 717 | /// ``` |
| 718 | /// |
| 719 | /// [syntax]: https://rust-lang.github.io/async-book/01_getting_started/04_async_await_primer.html |
| 720 | /// [instrument]: crate::Instrument |
| 721 | /// [attr]: macro@crate::instrument |
| 722 | /// |
| 723 | /// # Examples |
| 724 | /// |
| 725 | /// ``` |
| 726 | /// # use tracing::{span, Level}; |
| 727 | /// let span = span!(Level::INFO, "my_span"); |
| 728 | /// let guard = span.enter(); |
| 729 | /// |
| 730 | /// // code here is within the span |
| 731 | /// |
| 732 | /// drop(guard); |
| 733 | /// |
| 734 | /// // code here is no longer within the span |
| 735 | /// |
| 736 | /// ``` |
| 737 | /// |
| 738 | /// Guards need not be explicitly dropped: |
| 739 | /// |
| 740 | /// ``` |
| 741 | /// # use tracing::trace_span; |
| 742 | /// fn my_function() -> String { |
| 743 | /// // enter a span for the duration of this function. |
| 744 | /// let span = trace_span!("my_function"); |
| 745 | /// let _enter = span.enter(); |
| 746 | /// |
| 747 | /// // anything happening in functions we call is still inside the span... |
| 748 | /// my_other_function(); |
| 749 | /// |
| 750 | /// // returning from the function drops the guard, exiting the span. |
| 751 | /// return "Hello world".to_owned(); |
| 752 | /// } |
| 753 | /// |
| 754 | /// fn my_other_function() { |
| 755 | /// // ... |
| 756 | /// } |
| 757 | /// ``` |
| 758 | /// |
| 759 | /// Sub-scopes may be created to limit the duration for which the span is |
| 760 | /// entered: |
| 761 | /// |
| 762 | /// ``` |
| 763 | /// # use tracing::{info, info_span}; |
| 764 | /// let span = info_span!("my_great_span"); |
| 765 | /// |
| 766 | /// { |
| 767 | /// let _enter = span.enter(); |
| 768 | /// |
| 769 | /// // this event occurs inside the span. |
| 770 | /// info!("i'm in the span!"); |
| 771 | /// |
| 772 | /// // exiting the scope drops the guard, exiting the span. |
| 773 | /// } |
| 774 | /// |
| 775 | /// // this event is not inside the span. |
| 776 | /// info!("i'm outside the span!") |
| 777 | /// ``` |
| 778 | /// |
| 779 | /// [`Collect::enter`]: super::collect::Collect::enter() |
| 780 | /// [`Collect::exit`]: super::collect::Collect::exit() |
| 781 | /// [`Id`]: super::Id |
| 782 | #[inline(always)] |
| 783 | pub fn enter(&self) -> Entered<'_> { |
| 784 | self.do_enter(); |
| 785 | Entered { |
| 786 | span: self, |
| 787 | _not_send: PhantomNotSend, |
| 788 | } |
| 789 | } |
| 790 | |
| 791 | /// Enters this span, consuming it and returning a [guard][`EnteredSpan`] |
| 792 | /// that will exit the span when dropped. |
| 793 | /// |
| 794 | /// If this span is enabled by the current collector, then this function will |
| 795 | /// call [`Collect::enter`] with the span's [`Id`], and dropping the guard |
| 796 | /// will call [`Collect::exit`]. If the span is disabled, this does |
| 797 | /// nothing. |
| 798 | /// |
| 799 | /// This is similar to the [`Span::enter`] method, except that it moves the |
| 800 | /// span by value into the returned guard, rather than borrowing it. |
| 801 | /// Therefore, this method can be used to create and enter a span in a |
| 802 | /// single expression, without requiring a `let`-binding. For example: |
| 803 | /// |
| 804 | /// ``` |
| 805 | /// # use tracing::info_span; |
| 806 | /// let _span = info_span!("something_interesting").entered(); |
| 807 | /// ``` |
| 808 | /// rather than: |
| 809 | /// ``` |
| 810 | /// # use tracing::info_span; |
| 811 | /// let span = info_span!("something_interesting"); |
| 812 | /// let _e = span.enter(); |
| 813 | /// ``` |
| 814 | /// |
| 815 | /// Furthermore, `entered` may be used when the span must be stored in some |
| 816 | /// other struct or be passed to a function while remaining entered. |
| 817 | /// |
| 818 | /// <div class="example-wrap" style="display:inline-block"> |
| 819 | /// <pre class="ignore" style="white-space:normal;font:inherit;"> |
| 820 | /// |
| 821 | /// **Note**: The returned [`EnteredSpan`] guard does not |
| 822 | /// implement `Send`. Dropping the guard will exit *this* span, |
| 823 | /// and if the guard is sent to another thread and dropped there, that thread may |
| 824 | /// never have entered this span. Thus, `EnteredSpan`s should not be sent |
| 825 | /// between threads. |
| 826 | /// |
| 827 | /// </pre></div> |
| 828 | /// |
| 829 | /// **Warning**: in asynchronous code that uses [async/await syntax][syntax], |
| 830 | /// [`Span::entered`] should be used very carefully or avoided entirely. Holding |
| 831 | /// the drop guard returned by `Span::entered` across `.await` points will |
| 832 | /// result in incorrect traces. See the documentation for the |
| 833 | /// [`Span::enter`] method for details. |
| 834 | /// |
| 835 | /// [syntax]: https://rust-lang.github.io/async-book/01_getting_started/04_async_await_primer.html |
| 836 | /// |
| 837 | /// # Examples |
| 838 | /// |
| 839 | /// The returned guard can be [explicitly exited][EnteredSpan::exit], |
| 840 | /// returning the un-entered span: |
| 841 | /// |
| 842 | /// ``` |
| 843 | /// # use tracing::{Level, span}; |
| 844 | /// let span = span!(Level::INFO, "doing_something").entered(); |
| 845 | /// |
| 846 | /// // code here is within the span |
| 847 | /// |
| 848 | /// // explicitly exit the span, returning it |
| 849 | /// let span = span.exit(); |
| 850 | /// |
| 851 | /// // code here is no longer within the span |
| 852 | /// |
| 853 | /// // enter the span again |
| 854 | /// let span = span.entered(); |
| 855 | /// |
| 856 | /// // now we are inside the span once again |
| 857 | /// ``` |
| 858 | /// |
| 859 | /// Guards need not be explicitly dropped: |
| 860 | /// |
| 861 | /// ``` |
| 862 | /// # use tracing::trace_span; |
| 863 | /// fn my_function() -> String { |
| 864 | /// // enter a span for the duration of this function. |
| 865 | /// let span = trace_span!("my_function").entered(); |
| 866 | /// |
| 867 | /// // anything happening in functions we call is still inside the span... |
| 868 | /// my_other_function(); |
| 869 | /// |
| 870 | /// // returning from the function drops the guard, exiting the span. |
| 871 | /// return "Hello world".to_owned(); |
| 872 | /// } |
| 873 | /// |
| 874 | /// fn my_other_function() { |
| 875 | /// // ... |
| 876 | /// } |
| 877 | /// ``` |
| 878 | /// |
| 879 | /// Since the [`EnteredSpan`] guard can dereference to the [`Span`] itself, |
| 880 | /// the span may still be accessed while entered. For example: |
| 881 | /// |
| 882 | /// ```rust |
| 883 | /// # use tracing::info_span; |
| 884 | /// use tracing::field; |
| 885 | /// |
| 886 | /// // create the span with an empty field, and enter it. |
| 887 | /// let span = info_span!("my_span", some_field = field::Empty).entered(); |
| 888 | /// |
| 889 | /// // we can still record a value for the field while the span is entered. |
| 890 | /// span.record("some_field", &"hello world!"); |
| 891 | /// ``` |
| 892 | /// |
| 893 | /// [`Collect::enter`]: super::collect::Collect::enter() |
| 894 | /// [`Collect::exit`]: super::collect::Collect::exit() |
| 895 | /// [`Id`]: super::Id |
| 896 | #[inline(always)] |
| 897 | pub fn entered(self) -> EnteredSpan { |
| 898 | self.do_enter(); |
| 899 | EnteredSpan { |
| 900 | span: self, |
| 901 | _not_send: PhantomNotSend, |
| 902 | } |
| 903 | } |
| 904 | |
| 905 | /// Returns this span, if it was [enabled] by the current [collector], or |
| 906 | /// the [current span] (whose lexical distance may be further than expected), |
| 907 | /// if this span [is disabled]. |
| 908 | /// |
| 909 | /// This method can be useful when propagating spans to spawned threads or |
| 910 | /// [async tasks]. Consider the following: |
| 911 | /// |
| 912 | /// ``` |
| 913 | /// let _parent_span = tracing::info_span!("parent").entered(); |
| 914 | /// |
| 915 | /// // ... |
| 916 | /// |
| 917 | /// let child_span = tracing::debug_span!("child"); |
| 918 | /// |
| 919 | /// std::thread::spawn(move || { |
| 920 | /// let _entered = child_span.entered(); |
| 921 | /// |
| 922 | /// tracing::info!("spawned a thread!"); |
| 923 | /// |
| 924 | /// // ... |
| 925 | /// }); |
| 926 | /// ``` |
| 927 | /// |
| 928 | /// If the current [collector] enables the [`DEBUG`] level, then both |
| 929 | /// the "parent" and "child" spans will be enabled. Thus, when the "spawned |
| 930 | /// a thread!" event occurs, it will be inside of the "child" span. Because |
| 931 | /// "parent" is the parent of "child", the event will _also_ be inside of |
| 932 | /// "parent". |
| 933 | /// |
| 934 | /// However, if the collector only enables the [`INFO`] level, the "child" |
| 935 | /// span will be disabled. When the thread is spawned, the |
| 936 | /// `child_span.entered()` call will do nothing, since "child" is not |
| 937 | /// enabled. In this case, the "spawned a thread!" event occurs outside of |
| 938 | /// *any* span, since the "child" span was responsible for propagating its |
| 939 | /// parent to the spawned thread. |
| 940 | /// |
| 941 | /// If this is not the desired behavior, `Span::or_current` can be used to |
| 942 | /// ensure that the "parent" span is propagated in both cases, either as a |
| 943 | /// parent of "child" _or_ directly. For example: |
| 944 | /// |
| 945 | /// ``` |
| 946 | /// let _parent_span = tracing::info_span!("parent").entered(); |
| 947 | /// |
| 948 | /// // ... |
| 949 | /// |
| 950 | /// // If DEBUG is enabled, then "child" will be enabled, and `or_current` |
| 951 | /// // returns "child". Otherwise, if DEBUG is not enabled, "child" will be |
| 952 | /// // disabled, and `or_current` returns "parent". |
| 953 | /// let child_span = tracing::debug_span!("child").or_current(); |
| 954 | /// |
| 955 | /// std::thread::spawn(move || { |
| 956 | /// let _entered = child_span.entered(); |
| 957 | /// |
| 958 | /// tracing::info!("spawned a thread!"); |
| 959 | /// |
| 960 | /// // ... |
| 961 | /// }); |
| 962 | /// ``` |
| 963 | /// |
| 964 | /// When spawning [asynchronous tasks][async tasks], `Span::or_current` can |
| 965 | /// be used similarly, in combination with [`instrument`]: |
| 966 | /// |
| 967 | /// ``` |
| 968 | /// use tracing::Instrument; |
| 969 | /// # // lol |
| 970 | /// # mod tokio { |
| 971 | /// # pub(super) fn spawn(_: impl std::future::Future) {} |
| 972 | /// # } |
| 973 | /// |
| 974 | /// let _parent_span = tracing::info_span!("parent").entered(); |
| 975 | /// |
| 976 | /// // ... |
| 977 | /// |
| 978 | /// let child_span = tracing::debug_span!("child"); |
| 979 | /// |
| 980 | /// tokio::spawn( |
| 981 | /// async { |
| 982 | /// tracing::info!("spawned a task!"); |
| 983 | /// |
| 984 | /// // ... |
| 985 | /// |
| 986 | /// }.instrument(child_span.or_current()) |
| 987 | /// ); |
| 988 | /// ``` |
| 989 | /// |
| 990 | /// In general, `or_current` should be preferred over nesting an |
| 991 | /// [`instrument`] call inside of an [`in_current_span`] call, as using |
| 992 | /// `or_current` will be more efficient. |
| 993 | /// |
| 994 | /// ``` |
| 995 | /// use tracing::Instrument; |
| 996 | /// # // lol |
| 997 | /// # mod tokio { |
| 998 | /// # pub(super) fn spawn(_: impl std::future::Future) {} |
| 999 | /// # } |
| 1000 | /// async fn my_async_fn() { |
| 1001 | /// // ... |
| 1002 | /// } |
| 1003 | /// |
| 1004 | /// let _parent_span = tracing::info_span!("parent").entered(); |
| 1005 | /// |
| 1006 | /// // Do this: |
| 1007 | /// tokio::spawn( |
| 1008 | /// my_async_fn().instrument(tracing::debug_span!("child").or_current()) |
| 1009 | /// ); |
| 1010 | /// |
| 1011 | /// // ...rather than this: |
| 1012 | /// tokio::spawn( |
| 1013 | /// my_async_fn() |
| 1014 | /// .instrument(tracing::debug_span!("child")) |
| 1015 | /// .in_current_span() |
| 1016 | /// ); |
| 1017 | /// ``` |
| 1018 | /// |
| 1019 | /// [enabled]: crate::collect::Collect::enabled |
| 1020 | /// [collector]: crate::collect::Collect |
| 1021 | /// [current span]: Span::current |
| 1022 | /// [is disabled]: Span::is_disabled |
| 1023 | /// [`INFO`]: crate::Level::INFO |
| 1024 | /// [`DEBUG`]: crate::Level::DEBUG |
| 1025 | /// [async tasks]: std::task |
| 1026 | /// [`instrument`]: crate::instrument::Instrument::instrument |
| 1027 | /// [`in_current_span`]: crate::instrument::Instrument::in_current_span |
| 1028 | pub fn or_current(self) -> Self { |
| 1029 | if self.is_disabled() { |
| 1030 | return Self::current(); |
| 1031 | } |
| 1032 | self |
| 1033 | } |
| 1034 | |
| 1035 | #[inline(always)] |
| 1036 | fn do_enter(&self) { |
| 1037 | if let Some(inner) = self.inner.as_ref() { |
| 1038 | inner.collector.enter(&inner.id); |
| 1039 | } |
| 1040 | |
| 1041 | if_log_enabled! { crate::Level::TRACE, { |
| 1042 | if let Some(_meta) = self.meta { |
| 1043 | self.log(ACTIVITY_LOG_TARGET, log::Level::Trace, format_args!("-> {};", _meta.name())); |
| 1044 | } |
| 1045 | }} |
| 1046 | } |
| 1047 | |
| 1048 | // Called from [`Entered`] and [`EnteredSpan`] drops. |
| 1049 | // |
| 1050 | // Running this behaviour on drop rather than with an explicit function |
| 1051 | // call means that spans may still be exited when unwinding. |
| 1052 | #[inline(always)] |
| 1053 | fn do_exit(&self) { |
| 1054 | if let Some(inner) = self.inner.as_ref() { |
| 1055 | inner.collector.exit(&inner.id); |
| 1056 | } |
| 1057 | |
| 1058 | if_log_enabled! { crate::Level::TRACE, { |
| 1059 | if let Some(_meta) = self.meta { |
| 1060 | self.log(ACTIVITY_LOG_TARGET, log::Level::Trace, format_args!("<- {};", _meta.name())); |
| 1061 | } |
| 1062 | }} |
| 1063 | } |
| 1064 | |
| 1065 | /// Executes the given function in the context of this span. |
| 1066 | /// |
| 1067 | /// If this span is enabled, then this function enters the span, invokes `f` |
| 1068 | /// and then exits the span. If the span is disabled, `f` will still be |
| 1069 | /// invoked, but in the context of the currently-executing span (if there is |
| 1070 | /// one). |
| 1071 | /// |
| 1072 | /// Returns the result of evaluating `f`. |
| 1073 | /// |
| 1074 | /// # Examples |
| 1075 | /// |
| 1076 | /// ``` |
| 1077 | /// # use tracing::{trace, span, Level}; |
| 1078 | /// let my_span = span!(Level::TRACE, "my_span"); |
| 1079 | /// |
| 1080 | /// my_span.in_scope(|| { |
| 1081 | /// // this event occurs within the span. |
| 1082 | /// trace!("i'm in the span!"); |
| 1083 | /// }); |
| 1084 | /// |
| 1085 | /// // this event occurs outside the span. |
| 1086 | /// trace!("i'm not in the span!"); |
| 1087 | /// ``` |
| 1088 | /// |
| 1089 | /// Calling a function and returning the result: |
| 1090 | /// ``` |
| 1091 | /// # use tracing::{info_span, Level}; |
| 1092 | /// fn hello_world() -> String { |
| 1093 | /// "Hello world!".to_owned() |
| 1094 | /// } |
| 1095 | /// |
| 1096 | /// let span = info_span!("hello_world"); |
| 1097 | /// // the span will be entered for the duration of the call to |
| 1098 | /// // `hello_world`. |
| 1099 | /// let a_string = span.in_scope(hello_world); |
| 1100 | /// |
| 1101 | pub fn in_scope<F: FnOnce() -> T, T>(&self, f: F) -> T { |
| 1102 | let _enter = self.enter(); |
| 1103 | f() |
| 1104 | } |
| 1105 | |
| 1106 | /// Returns a [`Field`](super::field::Field) for the field with the |
| 1107 | /// given `name`, if one exists, |
| 1108 | pub fn field<Q>(&self, field: &Q) -> Option<field::Field> |
| 1109 | where |
| 1110 | Q: field::AsField + ?Sized, |
| 1111 | { |
| 1112 | self.metadata().and_then(|meta| field.as_field(meta)) |
| 1113 | } |
| 1114 | |
| 1115 | /// Returns true if this `Span` has a field for the given |
| 1116 | /// [`Field`](super::field::Field) or field name. |
| 1117 | #[inline] |
| 1118 | pub fn has_field<Q>(&self, field: &Q) -> bool |
| 1119 | where |
| 1120 | Q: field::AsField + ?Sized, |
| 1121 | { |
| 1122 | self.field(field).is_some() |
| 1123 | } |
| 1124 | |
| 1125 | /// Records that the field described by `field` has the value `value`. |
| 1126 | /// |
| 1127 | /// This may be used with [`field::Empty`] to declare fields whose values |
| 1128 | /// are not known when the span is created, and record them later: |
| 1129 | /// ``` |
| 1130 | /// use tracing::{trace_span, field}; |
| 1131 | /// |
| 1132 | /// // Create a span with two fields: `greeting`, with the value "hello world", and |
| 1133 | /// // `parting`, without a value. |
| 1134 | /// let span = trace_span!("my_span", greeting = "hello world", parting = field::Empty); |
| 1135 | /// |
| 1136 | /// // ... |
| 1137 | /// |
| 1138 | /// // Now, record a value for parting as well. |
| 1139 | /// // (note that the field name is passed as a string slice) |
| 1140 | /// span.record("parting", "goodbye world!"); |
| 1141 | /// ``` |
| 1142 | /// However, it may also be used to record a _new_ value for a field whose |
| 1143 | /// value was already recorded: |
| 1144 | /// ``` |
| 1145 | /// use tracing::info_span; |
| 1146 | /// # fn do_something() -> Result<(), ()> { Err(()) } |
| 1147 | /// |
| 1148 | /// // Initially, let's assume that our attempt to do something is going okay... |
| 1149 | /// let span = info_span!("doing_something", is_okay = true); |
| 1150 | /// let _e = span.enter(); |
| 1151 | /// |
| 1152 | /// match do_something() { |
| 1153 | /// Ok(something) => { |
| 1154 | /// // ... |
| 1155 | /// } |
| 1156 | /// Err(_) => { |
| 1157 | /// // Things are no longer okay! |
| 1158 | /// span.record("is_okay", false); |
| 1159 | /// } |
| 1160 | /// } |
| 1161 | /// ``` |
| 1162 | /// |
| 1163 | /// <div class="example-wrap" style="display:inline-block"> |
| 1164 | /// <pre class="ignore" style="white-space:normal;font:inherit;"> |
| 1165 | /// |
| 1166 | /// **Note**: The fields associated with a span are part of its [`Metadata`]. |
| 1167 | /// The [`Metadata`] describing a particular |
| 1168 | /// span is constructed statically when the span is created and cannot be extended later to |
| 1169 | /// add new fields. Therefore, you cannot record a value for a field that was not specified |
| 1170 | /// when the span was created: |
| 1171 | /// |
| 1172 | /// </pre></div> |
| 1173 | /// |
| 1174 | /// ``` |
| 1175 | /// use tracing::{trace_span, field}; |
| 1176 | /// |
| 1177 | /// // Create a span with two fields: `greeting`, with the value "hello world", and |
| 1178 | /// // `parting`, without a value. |
| 1179 | /// let span = trace_span!("my_span", greeting = "hello world", parting = field::Empty); |
| 1180 | /// |
| 1181 | /// // ... |
| 1182 | /// |
| 1183 | /// // Now, you try to record a value for a new field, `new_field`, which was not |
| 1184 | /// // declared as `Empty` or populated when you created `span`. |
| 1185 | /// // You won't get any error, but the assignment will have no effect! |
| 1186 | /// span.record("new_field", "interesting_value_you_really_need"); |
| 1187 | /// |
| 1188 | /// // Instead, all fields that may be recorded after span creation should be declared up front, |
| 1189 | /// // using field::Empty when a value is not known, as we did for `parting`. |
| 1190 | /// // This `record` call will indeed replace field::Empty with "you will be remembered". |
| 1191 | /// span.record("parting", "you will be remembered"); |
| 1192 | /// ``` |
| 1193 | /// |
| 1194 | /// <div class="example-wrap" style="display:inline-block"> |
| 1195 | /// <pre class="ignore" style="white-space:normal;font:inherit;"> |
| 1196 | /// **Note**: To record several values in just one call, see the [`record_all!`](crate::record_all!) macro. |
| 1197 | /// </pre></div> |
| 1198 | /// |
| 1199 | /// [`field::Empty`]: super::field::Empty |
| 1200 | /// [`Metadata`]: super::Metadata |
| 1201 | pub fn record<Q, V>(&self, field: &Q, value: V) -> &Self |
| 1202 | where |
| 1203 | Q: field::AsField + ?Sized, |
| 1204 | V: field::Value, |
| 1205 | { |
| 1206 | if let Some(meta) = self.meta { |
| 1207 | if let Some(field) = field.as_field(meta) { |
| 1208 | self.record_all( |
| 1209 | &meta |
| 1210 | .fields() |
| 1211 | .value_set(&[(&field, Some(&value as &dyn field::Value))]), |
| 1212 | ); |
| 1213 | } |
| 1214 | } |
| 1215 | |
| 1216 | self |
| 1217 | } |
| 1218 | |
| 1219 | /// Records all the fields in the provided `ValueSet`. |
| 1220 | #[doc(hidden)] |
| 1221 | pub fn record_all(&self, values: &field::ValueSet<'_>) -> &Self { |
| 1222 | let record = Record::new(values); |
| 1223 | if let Some(ref inner) = self.inner { |
| 1224 | inner.record(&record); |
| 1225 | } |
| 1226 | |
| 1227 | if let Some(_meta) = self.meta { |
| 1228 | if_log_enabled! { *_meta.level(), { |
| 1229 | let target = if record.is_empty() { |
| 1230 | LIFECYCLE_LOG_TARGET |
| 1231 | } else { |
| 1232 | _meta.target() |
| 1233 | }; |
| 1234 | self.log( |
| 1235 | target, |
| 1236 | level_to_log!(*_meta.level()), |
| 1237 | format_args!("{};{}", _meta.name(), crate::log::LogValueSet { values, is_first: false }), |
| 1238 | ); |
| 1239 | }} |
| 1240 | } |
| 1241 | |
| 1242 | self |
| 1243 | } |
| 1244 | |
| 1245 | /// Returns `true` if this span was disabled by the collector and does not |
| 1246 | /// exist. |
| 1247 | /// |
| 1248 | /// See also [`is_none`]. |
| 1249 | /// |
| 1250 | /// [`is_none`]: Span::is_none() |
| 1251 | #[inline] |
| 1252 | pub fn is_disabled(&self) -> bool { |
| 1253 | self.inner.is_none() |
| 1254 | } |
| 1255 | |
| 1256 | /// Returns `true` if this span was constructed by [`Span::none`] and is |
| 1257 | /// empty. |
| 1258 | /// |
| 1259 | /// If `is_none` returns `true` for a given span, then [`is_disabled`] will |
| 1260 | /// also return `true`. However, when a span is disabled by the collector |
| 1261 | /// rather than constructed by `Span::none`, this method will return |
| 1262 | /// `false`, while `is_disabled` will return `true`. |
| 1263 | /// |
| 1264 | /// [`is_disabled`]: Span::is_disabled() |
| 1265 | #[inline] |
| 1266 | pub fn is_none(&self) -> bool { |
| 1267 | self.is_disabled() && self.meta.is_none() |
| 1268 | } |
| 1269 | |
| 1270 | /// Indicates that the span with the given ID has an indirect causal |
| 1271 | /// relationship with this span. |
| 1272 | /// |
| 1273 | /// This relationship differs somewhat from the parent-child relationship: a |
| 1274 | /// span may have any number of prior spans, rather than a single one; and |
| 1275 | /// spans are not considered to be executing _inside_ of the spans they |
| 1276 | /// follow from. This means that a span may close even if subsequent spans |
| 1277 | /// that follow from it are still open, and time spent inside of a |
| 1278 | /// subsequent span should not be included in the time its precedents were |
| 1279 | /// executing. This is used to model causal relationships such as when a |
| 1280 | /// single future spawns several related background tasks, et cetera. |
| 1281 | /// |
| 1282 | /// If this span is disabled, or the resulting follows-from relationship |
| 1283 | /// would be invalid, this function will do nothing. |
| 1284 | /// |
| 1285 | /// # Examples |
| 1286 | /// |
| 1287 | /// Setting a `follows_from` relationship with a `Span`: |
| 1288 | /// ``` |
| 1289 | /// # use tracing::{span, Id, Level, Span}; |
| 1290 | /// let span1 = span!(Level::INFO, "span_1"); |
| 1291 | /// let span2 = span!(Level::DEBUG, "span_2"); |
| 1292 | /// span2.follows_from(&span1); |
| 1293 | /// ``` |
| 1294 | /// |
| 1295 | /// Setting a `follows_from` relationship with the current span: |
| 1296 | /// ``` |
| 1297 | /// # use tracing::{span, Id, Level, Span}; |
| 1298 | /// let span = span!(Level::INFO, "hello!"); |
| 1299 | /// span.follows_from(&Span::current()); |
| 1300 | /// ``` |
| 1301 | /// |
| 1302 | /// Setting a `follows_from` relationship with an `Id`: |
| 1303 | /// ``` |
| 1304 | /// # use tracing::{span, Id, Level, Span}; |
| 1305 | /// let span = span!(Level::INFO, "hello!"); |
| 1306 | /// let id = span.id(); |
| 1307 | /// span.follows_from(id); |
| 1308 | /// ``` |
| 1309 | pub fn follows_from(&self, from: impl Into<Option<Id>>) -> &Self { |
| 1310 | if let Some(ref inner) = self.inner { |
| 1311 | if let Some(from) = from.into() { |
| 1312 | inner.follows_from(&from); |
| 1313 | } |
| 1314 | } |
| 1315 | self |
| 1316 | } |
| 1317 | |
| 1318 | /// Returns this span's `Id`, if it is enabled. |
| 1319 | pub fn id(&self) -> Option<Id> { |
| 1320 | self.inner.as_ref().map(Inner::id) |
| 1321 | } |
| 1322 | |
| 1323 | /// Returns this span's `Metadata`, if it is enabled. |
| 1324 | pub fn metadata(&self) -> Option<&'static Metadata<'static>> { |
| 1325 | self.meta |
| 1326 | } |
| 1327 | |
| 1328 | #[cfg(feature = "log")] |
| 1329 | #[inline] |
| 1330 | fn log(&self, target: &str, level: log::Level, message: fmt::Arguments<'_>) { |
| 1331 | if let Some(meta) = self.meta { |
| 1332 | if level_to_log!(*meta.level()) <= log::max_level() { |
| 1333 | let logger = log::logger(); |
| 1334 | let log_meta = log::Metadata::builder().level(level).target(target).build(); |
| 1335 | if logger.enabled(&log_meta) { |
| 1336 | if let Some(ref inner) = self.inner { |
| 1337 | logger.log( |
| 1338 | &log::Record::builder() |
| 1339 | .metadata(log_meta) |
| 1340 | .module_path(meta.module_path()) |
| 1341 | .file(meta.file()) |
| 1342 | .line(meta.line()) |
| 1343 | .args(format_args!("{} span={}", message, inner.id.into_u64())) |
| 1344 | .build(), |
| 1345 | ); |
| 1346 | } else { |
| 1347 | logger.log( |
| 1348 | &log::Record::builder() |
| 1349 | .metadata(log_meta) |
| 1350 | .module_path(meta.module_path()) |
| 1351 | .file(meta.file()) |
| 1352 | .line(meta.line()) |
| 1353 | .args(message) |
| 1354 | .build(), |
| 1355 | ); |
| 1356 | } |
| 1357 | } |
| 1358 | } |
| 1359 | } |
| 1360 | } |
| 1361 | |
| 1362 | /// Invokes a function with a reference to this span's ID and collector. |
| 1363 | /// |
| 1364 | /// if this span is enabled, the provided function is called, and the result is returned. |
| 1365 | /// If the span is disabled, the function is not called, and this method returns `None` |
| 1366 | /// instead. |
| 1367 | pub fn with_collector<T>(&self, f: impl FnOnce((&Id, &Dispatch)) -> T) -> Option<T> { |
| 1368 | self.inner |
| 1369 | .as_ref() |
| 1370 | .map(|inner| f((&inner.id, &inner.collector))) |
| 1371 | } |
| 1372 | } |
| 1373 | |
| 1374 | impl cmp::PartialEq for Span { |
| 1375 | fn eq(&self, other: &Self) -> bool { |
| 1376 | match (&self.meta, &other.meta) { |
| 1377 | (Some(this), Some(that)) => { |
| 1378 | this.callsite() == that.callsite() && self.inner == other.inner |
| 1379 | } |
| 1380 | _ => false, |
| 1381 | } |
| 1382 | } |
| 1383 | } |
| 1384 | |
| 1385 | impl Hash for Span { |
| 1386 | fn hash<H: Hasher>(&self, hasher: &mut H) { |
| 1387 | self.inner.hash(hasher); |
| 1388 | } |
| 1389 | } |
| 1390 | |
| 1391 | impl fmt::Debug for Span { |
| 1392 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
| 1393 | let mut span = f.debug_struct("Span"); |
| 1394 | if let Some(meta) = self.meta { |
| 1395 | span.field("name", &meta.name()) |
| 1396 | .field("level", &meta.level()) |
| 1397 | .field("target", &meta.target()); |
| 1398 | |
| 1399 | if let Some(ref inner) = self.inner { |
| 1400 | span.field("id", &inner.id()); |
| 1401 | } else { |
| 1402 | span.field("disabled", &true); |
| 1403 | } |
| 1404 | |
| 1405 | if let Some(ref path) = meta.module_path() { |
| 1406 | span.field("module_path", &path); |
| 1407 | } |
| 1408 | |
| 1409 | if let Some(ref line) = meta.line() { |
| 1410 | span.field("line", &line); |
| 1411 | } |
| 1412 | |
| 1413 | if let Some(ref file) = meta.file() { |
| 1414 | span.field("file", &file); |
| 1415 | } |
| 1416 | } else { |
| 1417 | span.field("none", &true); |
| 1418 | } |
| 1419 | |
| 1420 | span.finish() |
| 1421 | } |
| 1422 | } |
| 1423 | |
| 1424 | impl<'a> From<&'a Span> for Option<&'a Id> { |
| 1425 | fn from(span: &'a Span) -> Self { |
| 1426 | span.inner.as_ref().map(|inner| &inner.id) |
| 1427 | } |
| 1428 | } |
| 1429 | |
| 1430 | impl<'a> From<&'a Span> for Option<Id> { |
| 1431 | fn from(span: &'a Span) -> Self { |
| 1432 | span.inner.as_ref().map(Inner::id) |
| 1433 | } |
| 1434 | } |
| 1435 | |
| 1436 | impl<'a> From<&'a EnteredSpan> for Option<&'a Id> { |
| 1437 | fn from(span: &'a EnteredSpan) -> Self { |
| 1438 | span.inner.as_ref().map(|inner| &inner.id) |
| 1439 | } |
| 1440 | } |
| 1441 | |
| 1442 | impl<'a> From<&'a EnteredSpan> for Option<Id> { |
| 1443 | fn from(span: &'a EnteredSpan) -> Self { |
| 1444 | span.inner.as_ref().map(Inner::id) |
| 1445 | } |
| 1446 | } |
| 1447 | |
| 1448 | impl Drop for Span { |
| 1449 | #[inline(always)] |
| 1450 | fn drop(&mut self) { |
| 1451 | if let Some(Inner { |
| 1452 | ref id, |
| 1453 | ref collector, |
| 1454 | }) = self.inner |
| 1455 | { |
| 1456 | collector.try_close(id.clone()); |
| 1457 | } |
| 1458 | |
| 1459 | if_log_enabled! { crate::Level::TRACE, { |
| 1460 | if let Some(meta) = self.meta { |
| 1461 | self.log( |
| 1462 | LIFECYCLE_LOG_TARGET, |
| 1463 | log::Level::Trace, |
| 1464 | format_args!("-- {};", meta.name()), |
| 1465 | ); |
| 1466 | } |
| 1467 | }} |
| 1468 | } |
| 1469 | } |
| 1470 | |
| 1471 | // ===== impl Inner ===== |
| 1472 | |
| 1473 | impl Inner { |
| 1474 | /// Indicates that the span with the given ID has an indirect causal |
| 1475 | /// relationship with this span. |
| 1476 | /// |
| 1477 | /// This relationship differs somewhat from the parent-child relationship: a |
| 1478 | /// span may have any number of prior spans, rather than a single one; and |
| 1479 | /// spans are not considered to be executing _inside_ of the spans they |
| 1480 | /// follow from. This means that a span may close even if subsequent spans |
| 1481 | /// that follow from it are still open, and time spent inside of a |
| 1482 | /// subsequent span should not be included in the time its precedents were |
| 1483 | /// executing. This is used to model causal relationships such as when a |
| 1484 | /// single future spawns several related background tasks, et cetera. |
| 1485 | /// |
| 1486 | /// If this span is disabled, this function will do nothing. Otherwise, it |
| 1487 | /// returns `Ok(())` if the other span was added as a precedent of this |
| 1488 | /// span, or an error if this was not possible. |
| 1489 | fn follows_from(&self, from: &Id) { |
| 1490 | self.collector.record_follows_from(&self.id, from) |
| 1491 | } |
| 1492 | |
| 1493 | /// Returns the span's ID. |
| 1494 | fn id(&self) -> Id { |
| 1495 | self.id.clone() |
| 1496 | } |
| 1497 | |
| 1498 | fn record(&self, values: &Record<'_>) { |
| 1499 | self.collector.record(&self.id, values) |
| 1500 | } |
| 1501 | |
| 1502 | fn new(id: Id, collector: &Dispatch) -> Self { |
| 1503 | Inner { |
| 1504 | id, |
| 1505 | collector: collector.clone(), |
| 1506 | } |
| 1507 | } |
| 1508 | } |
| 1509 | |
| 1510 | impl cmp::PartialEq for Inner { |
| 1511 | fn eq(&self, other: &Self) -> bool { |
| 1512 | self.id == other.id |
| 1513 | } |
| 1514 | } |
| 1515 | |
| 1516 | impl Hash for Inner { |
| 1517 | fn hash<H: Hasher>(&self, state: &mut H) { |
| 1518 | self.id.hash(state); |
| 1519 | } |
| 1520 | } |
| 1521 | |
| 1522 | impl Clone for Inner { |
| 1523 | fn clone(&self) -> Self { |
| 1524 | Inner { |
| 1525 | id: self.collector.clone_span(&self.id), |
| 1526 | collector: self.collector.clone(), |
| 1527 | } |
| 1528 | } |
| 1529 | } |
| 1530 | |
| 1531 | // ===== impl Entered ===== |
| 1532 | |
| 1533 | impl EnteredSpan { |
| 1534 | /// Returns this span's `Id`, if it is enabled. |
| 1535 | pub fn id(&self) -> Option<Id> { |
| 1536 | self.inner.as_ref().map(Inner::id) |
| 1537 | } |
| 1538 | |
| 1539 | /// Exits this span, returning the underlying [`Span`]. |
| 1540 | #[inline] |
| 1541 | pub fn exit(mut self) -> Span { |
| 1542 | // One does not simply move out of a struct with `Drop`. |
| 1543 | let span = mem::replace(&mut self.span, Span::none()); |
| 1544 | span.do_exit(); |
| 1545 | span |
| 1546 | } |
| 1547 | } |
| 1548 | |
| 1549 | impl Deref for EnteredSpan { |
| 1550 | type Target = Span; |
| 1551 | |
| 1552 | #[inline] |
| 1553 | fn deref(&self) -> &Span { |
| 1554 | &self.span |
| 1555 | } |
| 1556 | } |
| 1557 | |
| 1558 | impl Drop for Entered<'_> { |
| 1559 | #[inline(always)] |
| 1560 | fn drop(&mut self) { |
| 1561 | self.span.do_exit() |
| 1562 | } |
| 1563 | } |
| 1564 | |
| 1565 | impl Drop for EnteredSpan { |
| 1566 | #[inline(always)] |
| 1567 | fn drop(&mut self) { |
| 1568 | self.span.do_exit() |
| 1569 | } |
| 1570 | } |
| 1571 | |
| 1572 | /// Technically, `Entered` (or `EnteredSpan`) _can_ implement both `Send` *and* |
| 1573 | /// `Sync` safely. It doesn't, because it has a `PhantomNotSend` field, |
| 1574 | /// specifically added in order to make it `!Send`. |
| 1575 | /// |
| 1576 | /// Sending an `Entered` guard between threads cannot cause memory unsafety. |
| 1577 | /// However, it *would* result in incorrect behavior, so we add a |
| 1578 | /// `PhantomNotSend` to prevent it from being sent between threads. This is |
| 1579 | /// because it must be *dropped* on the same thread that it was created; |
| 1580 | /// otherwise, the span will never be exited on the thread where it was entered, |
| 1581 | /// and it will attempt to exit the span on a thread that may never have entered |
| 1582 | /// it. However, we still want them to be `Sync` so that a struct holding an |
| 1583 | /// `Entered` guard can be `Sync`. |
| 1584 | /// |
| 1585 | /// Thus, this is totally safe. |
| 1586 | #[derive(Debug)] |
| 1587 | struct PhantomNotSend { |
| 1588 | ghost: PhantomData<*mut ()>, |
| 1589 | } |
| 1590 | |
| 1591 | #[allow(non_upper_case_globals)] |
| 1592 | const PhantomNotSend: PhantomNotSend = PhantomNotSend { ghost: PhantomData }; |
| 1593 | |
| 1594 | /// # Safety |
| 1595 | /// |
| 1596 | /// Trivially safe, as `PhantomNotSend` doesn't have any API. |
| 1597 | unsafe impl Sync for PhantomNotSend {} |
| 1598 | |
| 1599 | #[cfg(test)] |
| 1600 | mod test { |
| 1601 | use super::*; |
| 1602 | |
| 1603 | #[allow(dead_code)] |
| 1604 | trait AssertSend: Send {} |
| 1605 | impl AssertSend for Span {} |
| 1606 | |
| 1607 | #[allow(dead_code)] |
| 1608 | trait AssertSync: Sync {} |
| 1609 | impl AssertSync for Span {} |
| 1610 | impl AssertSync for Entered<'_> {} |
| 1611 | impl AssertSync for EnteredSpan {} |
| 1612 | |
| 1613 | #[test] |
| 1614 | fn test_record_backwards_compat() { |
| 1615 | Span::current().record("some-key", "some text"); |
| 1616 | Span::current().record("some-key", false); |
| 1617 | } |
| 1618 | } |