edlang/tracing_subscriber/fmt/fn.fmt.html
2024-03-27 11:12:16 +00:00

45 lines
7.5 KiB
HTML
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta name="generator" content="rustdoc"><meta name="description" content="Returns a new `SubscriberBuilder` for configuring a formatting subscriber."><title>fmt in tracing_subscriber::fmt - Rust</title><link rel="preload" as="font" type="font/woff2" crossorigin href="../../static.files/SourceSerif4-Regular-46f98efaafac5295.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../static.files/FiraSans-Regular-018c141bf0843ffd.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../static.files/FiraSans-Medium-8f9a781e4970d388.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../static.files/SourceCodePro-Regular-562dcc5011b6de7d.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../static.files/SourceCodePro-Semibold-d899c5a5c4aeb14a.ttf.woff2"><link rel="stylesheet" href="../../static.files/normalize-76eba96aa4d2e634.css"><link rel="stylesheet" href="../../static.files/rustdoc-5bc39a1768837dd0.css"><meta name="rustdoc-vars" data-root-path="../../" data-static-root-path="../../static.files/" data-current-crate="tracing_subscriber" data-themes="" data-resource-suffix="" data-rustdoc-version="1.77.0 (aedd173a2 2024-03-17)" data-channel="1.77.0" data-search-js="search-dd67cee4cfa65049.js" data-settings-js="settings-4313503d2e1961c2.js" ><script src="../../static.files/storage-4c98445ec4002617.js"></script><script defer src="sidebar-items.js"></script><script defer src="../../static.files/main-48f368f3872407c8.js"></script><noscript><link rel="stylesheet" href="../../static.files/noscript-04d5337699b92874.css"></noscript><link rel="alternate icon" type="image/png" href="../../static.files/favicon-16x16-8b506e7a72182f1c.png"><link rel="alternate icon" type="image/png" href="../../static.files/favicon-32x32-422f7d1d52889060.png"><link rel="icon" type="image/svg+xml" href="../../static.files/favicon-2c020d218678b618.svg"></head><body class="rustdoc fn"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="mobile-topbar"><button class="sidebar-menu-toggle" title="show sidebar"></button><a class="logo-container" href="../../tracing_subscriber/index.html"><img src="https://raw.githubusercontent.com/tokio-rs/tracing/master/assets/logo-type.png" alt=""></a></nav><nav class="sidebar"><div class="sidebar-crate"><a class="logo-container" href="../../tracing_subscriber/index.html"><img src="https://raw.githubusercontent.com/tokio-rs/tracing/master/assets/logo-type.png" alt="logo"></a><h2><a href="../../tracing_subscriber/index.html">tracing_subscriber</a><span class="version">0.3.18</span></h2></div><div class="sidebar-elems"><h2><a href="index.html">In tracing_subscriber::fmt</a></h2></div></nav><div class="sidebar-resizer"></div>
<main><div class="width-limiter"><nav class="sub"><form class="search-form"><span></span><div id="sidebar-button" tabindex="-1"><a href="../../tracing_subscriber/all.html" title="show sidebar"></a></div><input class="search-input" name="search" aria-label="Run search in the documentation" autocomplete="off" spellcheck="false" placeholder="Click or press S to search, ? for more options…" type="search"><div id="help-button" tabindex="-1"><a href="../../help.html" title="help">?</a></div><div id="settings-menu" tabindex="-1"><a href="../../settings.html" title="settings"><img width="22" height="22" alt="Change settings" src="../../static.files/wheel-7b819b6101059cd0.svg"></a></div></form></nav><section id="main-content" class="content"><div class="main-heading"><h1>Function <a href="../index.html">tracing_subscriber</a>::<wbr><a href="index.html">fmt</a>::<wbr><a class="fn" href="#">fmt</a><button id="copy-path" title="Copy item path to clipboard"><img src="../../static.files/clipboard-7571035ce49a181d.svg" width="19" height="18" alt="Copy item path"></button></h1><span class="out-of-band"><a class="src" href="../../src/tracing_subscriber/fmt/mod.rs.html#321-323">source</a> · <button id="toggle-all-docs" title="collapse all docs">[<span>&#x2212;</span>]</button></span></div><pre class="rust item-decl"><code>pub fn fmt() -&gt; <a class="struct" href="struct.SubscriberBuilder.html" title="struct tracing_subscriber::fmt::SubscriberBuilder">SubscriberBuilder</a></code></pre><details class="toggle top-doc" open><summary class="hideme"><span>Expand description</span></summary><div class="docblock"><p>Returns a new <a href="struct.SubscriberBuilder.html" title="struct tracing_subscriber::fmt::SubscriberBuilder"><code>SubscriberBuilder</code></a> for configuring a <a href="struct.Subscriber.html" title="struct tracing_subscriber::fmt::Subscriber">formatting subscriber</a>.</p>
<p>This is essentially shorthand for [<code>SubscriberBuilder::default()]</code>.</p>
<h2 id="examples"><a class="doc-anchor" href="#examples">§</a>Examples</h2>
<p>Using <a href="struct.SubscriberBuilder.html#method.init" title="method tracing_subscriber::fmt::SubscriberBuilder::init"><code>init</code></a> to set the default subscriber:</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code>tracing_subscriber::fmt().init();</code></pre></div>
<p>Configuring the output format:</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code>
tracing_subscriber::fmt()
<span class="comment">// Configure formatting settings.
</span>.with_target(<span class="bool-val">false</span>)
.with_timer(tracing_subscriber::fmt::time::uptime())
.with_level(<span class="bool-val">true</span>)
<span class="comment">// Set the subscriber as the default.
</span>.init();</code></pre></div>
<p><a href="struct.SubscriberBuilder.html#method.try_init" title="method tracing_subscriber::fmt::SubscriberBuilder::try_init"><code>try_init</code></a> returns an error if the default subscriber could not be set:</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>std::error::Error;
<span class="kw">fn </span>init_subscriber() -&gt; <span class="prelude-ty">Result</span>&lt;(), Box&lt;<span class="kw">dyn </span>Error + Send + Sync + <span class="lifetime">'static</span>&gt;&gt; {
tracing_subscriber::fmt()
<span class="comment">// Configure the subscriber to emit logs in JSON format.
</span>.json()
<span class="comment">// Configure the subscriber to flatten event fields in the output JSON objects.
</span>.flatten_event(<span class="bool-val">true</span>)
<span class="comment">// Set the subscriber as the default, returning an error if this fails.
</span>.try_init()<span class="question-mark">?</span>;
<span class="prelude-val">Ok</span>(())
}</code></pre></div>
<p>Rather than setting the subscriber as the default, <a href="struct.SubscriberBuilder.html#method.finish" title="method tracing_subscriber::fmt::SubscriberBuilder::finish"><code>finish</code></a> <em>returns</em> the
constructed subscriber, which may then be passed to other functions:</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">let </span>subscriber = tracing_subscriber::fmt()
.with_max_level(tracing::Level::DEBUG)
.compact()
.finish();
tracing::subscriber::with_default(subscriber, || {
<span class="comment">// the subscriber will only be set as the default
// inside this closure...
</span>})</code></pre></div>
</div></details></section></div></main></body></html>