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<h3>Table of Contents</h3>
<ul class="link-list" role="directory">
<li><a href="#class-Logger-label-Description">Description</a>
<li><a href="#class-Logger-label-Example">Example</a>
<li><a href="#class-Logger-label-Features">Features</a>
<li><a href="#class-Logger-label-HOWTOs">HOWTOs</a>
<li><a href="#class-Logger-label-How+to+create+a+logger">How to create a logger</a>
<li><a href="#class-Logger-label-How+to+log+a+message">How to log a message</a>
<li><a href="#class-Logger-label-How+to+close+a+logger">How to close a logger</a>
<li><a href="#class-Logger-label-Setting+severity+threshold">Setting severity threshold</a>
<li><a href="#class-Logger-label-Format">Format</a>
</ul>
</div>
<div id="class-metadata">
<div id="parent-class-section" class="nav-section">
<h3>Parent</h3>
<p class="link"><a href="Object.html">Object</a>
</div>
<div id="includes-section" class="nav-section">
<h3>Included Modules</h3>
<ul class="link-list">
<li><span class="include">Severity</span>
</ul>
</div>
<!-- Method Quickref -->
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<h3>Methods</h3>
<ul class="link-list" role="directory">
<li ><a href="#method-c-new">::new</a>
<li ><a href="#method-i-3C-3C">#<<</a>
<li ><a href="#method-i-add">#add</a>
<li ><a href="#method-i-close">#close</a>
<li ><a href="#method-i-datetime_format">#datetime_format</a>
<li ><a href="#method-i-datetime_format-3D">#datetime_format=</a>
<li ><a href="#method-i-debug">#debug</a>
<li ><a href="#method-i-debug-21">#debug!</a>
<li ><a href="#method-i-debug-3F">#debug?</a>
<li ><a href="#method-i-error">#error</a>
<li ><a href="#method-i-error-21">#error!</a>
<li ><a href="#method-i-error-3F">#error?</a>
<li ><a href="#method-i-fatal">#fatal</a>
<li ><a href="#method-i-fatal-21">#fatal!</a>
<li ><a href="#method-i-fatal-3F">#fatal?</a>
<li ><a href="#method-i-format_message">#format_message</a>
<li ><a href="#method-i-format_severity">#format_severity</a>
<li ><a href="#method-i-info">#info</a>
<li ><a href="#method-i-info-21">#info!</a>
<li ><a href="#method-i-info-3F">#info?</a>
<li ><a href="#method-i-level-3D">#level=</a>
<li ><a href="#method-i-log">#log</a>
<li ><a href="#method-i-reopen">#reopen</a>
<li ><a href="#method-i-sev_threshold-3D">#sev_threshold=</a>
<li ><a href="#method-i-unknown">#unknown</a>
<li ><a href="#method-i-warn">#warn</a>
<li ><a href="#method-i-warn-21">#warn!</a>
<li ><a href="#method-i-warn-3F">#warn?</a>
</ul>
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<main role="main" aria-labelledby="class-Logger">
<h1 id="class-Logger" class="class">
class Logger
</h1>
<section class="description">
<h2 id="class-Logger-label-Description">Description<span><a href="#class-Logger-label-Description">¶</a> <a href="#top">↑</a></span></h2>
<p>The <a href="Logger.html"><code>Logger</code></a> class provides a simple but sophisticated logging utility that you can use to output messages.</p>
<p>The messages have associated levels, such as <code>INFO</code> or <code>ERROR</code> that indicate their importance. You can then give the <a href="Logger.html"><code>Logger</code></a> a level, and only messages at that level or higher will be printed.</p>
<p>The levels are:</p>
<dl class="rdoc-list note-list"><dt><code>UNKNOWN</code>
<dd>
<p>An unknown message that should always be logged.</p>
</dd><dt><code>FATAL</code>
<dd>
<p>An unhandleable error that results in a program crash.</p>
</dd><dt><code>ERROR</code>
<dd>
<p>A handleable error condition.</p>
</dd><dt><code>WARN</code>
<dd>
<p>A warning.</p>
</dd><dt><code>INFO</code>
<dd>
<p>Generic (useful) information about system operation.</p>
</dd><dt><code>DEBUG</code>
<dd>
<p>Low-level information for developers.</p>
</dd></dl>
<p>For instance, in a production system, you may have your <a href="Logger.html"><code>Logger</code></a> set to <code>INFO</code> or even <code>WARN</code>. When you are developing the system, however, you probably want to know about the program's internal state, and would set the <a href="Logger.html"><code>Logger</code></a> to <code>DEBUG</code>.</p>
<p><strong>Note</strong>: <a href="Logger.html"><code>Logger</code></a> does not escape or sanitize any messages passed to it. Developers should be aware of when potentially malicious data (user-input) is passed to <a href="Logger.html"><code>Logger</code></a>, and manually escape the untrusted data:</p>
<pre class="ruby"><span class="ruby-identifier">logger</span>.<span class="ruby-identifier">info</span>(<span class="ruby-node">"User-input: #{input.dump}"</span>)
<span class="ruby-identifier">logger</span>.<span class="ruby-identifier">info</span>(<span class="ruby-string">"User-input: %p"</span> <span class="ruby-operator">%</span> <span class="ruby-identifier">input</span>)
</pre>
<p>You can use <a href="Logger.html#attribute-i-formatter"><code>formatter=</code></a> for escaping all data.</p>
<pre class="ruby"><span class="ruby-identifier">original_formatter</span> = <span class="ruby-constant">Logger</span><span class="ruby-operator">::</span><span class="ruby-constant">Formatter</span>.<span class="ruby-identifier">new</span>
<span class="ruby-identifier">logger</span>.<span class="ruby-identifier">formatter</span> = <span class="ruby-identifier">proc</span> { <span class="ruby-operator">|</span><span class="ruby-identifier">severity</span>, <span class="ruby-identifier">datetime</span>, <span class="ruby-identifier">progname</span>, <span class="ruby-identifier">msg</span><span class="ruby-operator">|</span>
<span class="ruby-identifier">original_formatter</span>.<span class="ruby-identifier">call</span>(<span class="ruby-identifier">severity</span>, <span class="ruby-identifier">datetime</span>, <span class="ruby-identifier">progname</span>, <span class="ruby-identifier">msg</span>.<span class="ruby-identifier">dump</span>)
}
<span class="ruby-identifier">logger</span>.<span class="ruby-identifier">info</span>(<span class="ruby-identifier">input</span>)
</pre>
<h3 id="class-Logger-label-Example">Example<span><a href="#class-Logger-label-Example">¶</a> <a href="#top">↑</a></span></h3>
<p>This creates a <a href="Logger.html"><code>Logger</code></a> that outputs to the standard output stream, with a level of <code>WARN</code>:</p>
<pre class="ruby"><span class="ruby-identifier">require</span> <span class="ruby-string">'logger'</span>
<span class="ruby-identifier">logger</span> = <span class="ruby-constant">Logger</span>.<span class="ruby-identifier">new</span>(<span class="ruby-constant">STDOUT</span>)
<span class="ruby-identifier">logger</span>.<span class="ruby-identifier">level</span> = <span class="ruby-constant">Logger</span><span class="ruby-operator">::</span><span class="ruby-constant">WARN</span>
<span class="ruby-identifier">logger</span>.<span class="ruby-identifier">debug</span>(<span class="ruby-string">"Created logger"</span>)
<span class="ruby-identifier">logger</span>.<span class="ruby-identifier">info</span>(<span class="ruby-string">"Program started"</span>)
<span class="ruby-identifier">logger</span>.<span class="ruby-identifier">warn</span>(<span class="ruby-string">"Nothing to do!"</span>)
<span class="ruby-identifier">path</span> = <span class="ruby-string">"a_non_existent_file"</span>
<span class="ruby-keyword">begin</span>
<span class="ruby-constant">File</span>.<span class="ruby-identifier">foreach</span>(<span class="ruby-identifier">path</span>) <span class="ruby-keyword">do</span> <span class="ruby-operator">|</span><span class="ruby-identifier">line</span><span class="ruby-operator">|</span>
<span class="ruby-keyword">unless</span> <span class="ruby-identifier">line</span> <span class="ruby-operator">=~</span> <span class="ruby-regexp">/^(\w+) = (.*)$/</span>
<span class="ruby-identifier">logger</span>.<span class="ruby-identifier">error</span>(<span class="ruby-node">"Line in wrong format: #{line.chomp}"</span>)
<span class="ruby-keyword">end</span>
<span class="ruby-keyword">end</span>
<span class="ruby-keyword">rescue</span> <span class="ruby-operator">=></span> <span class="ruby-identifier">err</span>
<span class="ruby-identifier">logger</span>.<span class="ruby-identifier">fatal</span>(<span class="ruby-string">"Caught exception; exiting"</span>)
<span class="ruby-identifier">logger</span>.<span class="ruby-identifier">fatal</span>(<span class="ruby-identifier">err</span>)
<span class="ruby-keyword">end</span>
</pre>
<p>Because the Logger's level is set to <code>WARN</code>, only the warning, error, and fatal messages are recorded. The debug and info messages are silently discarded.</p>
<h3 id="class-Logger-label-Features">Features<span><a href="#class-Logger-label-Features">¶</a> <a href="#top">↑</a></span></h3>
<p>There are several interesting features that <a href="Logger.html"><code>Logger</code></a> provides, like auto-rolling of log files, setting the format of log messages, and specifying a program name in conjunction with the message. The next section shows you how to achieve these things.</p>
<h2 id="class-Logger-label-HOWTOs">HOWTOs<span><a href="#class-Logger-label-HOWTOs">¶</a> <a href="#top">↑</a></span></h2>
<h3 id="class-Logger-label-How+to+create+a+logger">How to create a logger<span><a href="#class-Logger-label-How+to+create+a+logger">¶</a> <a href="#top">↑</a></span></h3>
<p>The options below give you various choices, in more or less increasing complexity.</p>
<ol><li>
<p>Create a logger which logs messages to STDERR/STDOUT.</p>
<pre class="ruby"><span class="ruby-identifier">logger</span> = <span class="ruby-constant">Logger</span>.<span class="ruby-identifier">new</span>(<span class="ruby-constant">STDERR</span>)
<span class="ruby-identifier">logger</span> = <span class="ruby-constant">Logger</span>.<span class="ruby-identifier">new</span>(<span class="ruby-constant">STDOUT</span>)
</pre>
</li><li>
<p>Create a logger for the file which has the specified name.</p>
<pre class="ruby"><span class="ruby-identifier">logger</span> = <span class="ruby-constant">Logger</span>.<span class="ruby-identifier">new</span>(<span class="ruby-string">'logfile.log'</span>)
</pre>
</li><li>
<p>Create a logger for the specified file.</p>
<pre class="ruby"><span class="ruby-identifier">file</span> = <span class="ruby-constant">File</span>.<span class="ruby-identifier">open</span>(<span class="ruby-string">'foo.log'</span>, <span class="ruby-constant">File</span><span class="ruby-operator">::</span><span class="ruby-constant">WRONLY</span> <span class="ruby-operator">|</span> <span class="ruby-constant">File</span><span class="ruby-operator">::</span><span class="ruby-constant">APPEND</span>)
<span class="ruby-comment"># To create new logfile, add File::CREAT like:</span>
<span class="ruby-comment"># file = File.open('foo.log', File::WRONLY | File::APPEND | File::CREAT)</span>
<span class="ruby-identifier">logger</span> = <span class="ruby-constant">Logger</span>.<span class="ruby-identifier">new</span>(<span class="ruby-identifier">file</span>)
</pre>
</li><li>
<p>Create a logger which ages the logfile once it reaches a certain size. Leave 10 “old” log files where each file is about 1,024,000 bytes.</p>
<pre class="ruby"><span class="ruby-identifier">logger</span> = <span class="ruby-constant">Logger</span>.<span class="ruby-identifier">new</span>(<span class="ruby-string">'foo.log'</span>, <span class="ruby-value">10</span>, <span class="ruby-value">1024000</span>)
</pre>
</li><li>
<p>Create a logger which ages the logfile daily/weekly/monthly.</p>
<pre class="ruby"><span class="ruby-identifier">logger</span> = <span class="ruby-constant">Logger</span>.<span class="ruby-identifier">new</span>(<span class="ruby-string">'foo.log'</span>, <span class="ruby-string">'daily'</span>)
<span class="ruby-identifier">logger</span> = <span class="ruby-constant">Logger</span>.<span class="ruby-identifier">new</span>(<span class="ruby-string">'foo.log'</span>, <span class="ruby-string">'weekly'</span>)
<span class="ruby-identifier">logger</span> = <span class="ruby-constant">Logger</span>.<span class="ruby-identifier">new</span>(<span class="ruby-string">'foo.log'</span>, <span class="ruby-string">'monthly'</span>)
</pre>
</li></ol>
<h3 id="class-Logger-label-How+to+log+a+message">How to log a message<span><a href="#class-Logger-label-How+to+log+a+message">¶</a> <a href="#top">↑</a></span></h3>
<p>Notice the different methods (<code>fatal</code>, <code>error</code>, <code>info</code>) being used to log messages of various levels? Other methods in this family are <code>warn</code> and <code>debug</code>. <code>add</code> is used below to log a message of an arbitrary (perhaps dynamic) level.</p>
<ol><li>
<p>Message in a block.</p>
<pre class="ruby"><span class="ruby-identifier">logger</span>.<span class="ruby-identifier">fatal</span> { <span class="ruby-string">"Argument 'foo' not given."</span> }
</pre>
</li><li>
<p>Message as a string.</p>
<pre class="ruby"><span class="ruby-identifier">logger</span>.<span class="ruby-identifier">error</span> <span class="ruby-node">"Argument #{@foo} mismatch."</span>
</pre>
</li><li>
<p>With progname.</p>
<pre class="ruby"><span class="ruby-identifier">logger</span>.<span class="ruby-identifier">info</span>(<span class="ruby-string">'initialize'</span>) { <span class="ruby-string">"Initializing..."</span> }
</pre>
</li><li>
<p>With severity.</p>
<pre class="ruby"><span class="ruby-identifier">logger</span>.<span class="ruby-identifier">add</span>(<span class="ruby-constant">Logger</span><span class="ruby-operator">::</span><span class="ruby-constant">FATAL</span>) { <span class="ruby-string">'Fatal error!'</span> }
</pre>
</li></ol>
<p>The block form allows you to create potentially complex log messages, but to delay their evaluation until and unless the message is logged. For example, if we have the following:</p>
<pre class="ruby"><span class="ruby-identifier">logger</span>.<span class="ruby-identifier">debug</span> { <span class="ruby-string">"This is a "</span> <span class="ruby-operator">+</span> <span class="ruby-identifier">potentially</span> <span class="ruby-operator">+</span> <span class="ruby-string">" expensive operation"</span> }
</pre>
<p>If the logger's level is <code>INFO</code> or higher, no debug messages will be logged, and the entire block will not even be evaluated. Compare to this:</p>
<pre class="ruby"><span class="ruby-identifier">logger</span>.<span class="ruby-identifier">debug</span>(<span class="ruby-string">"This is a "</span> <span class="ruby-operator">+</span> <span class="ruby-identifier">potentially</span> <span class="ruby-operator">+</span> <span class="ruby-string">" expensive operation"</span>)
</pre>
<p>Here, the string concatenation is done every time, even if the log level is not set to show the debug message.</p>
<h3 id="class-Logger-label-How+to+close+a+logger">How to close a logger<span><a href="#class-Logger-label-How+to+close+a+logger">¶</a> <a href="#top">↑</a></span></h3>
<pre class="ruby"><span class="ruby-identifier">logger</span>.<span class="ruby-identifier">close</span>
</pre>
<h3 id="class-Logger-label-Setting+severity+threshold">Setting severity threshold<span><a href="#class-Logger-label-Setting+severity+threshold">¶</a> <a href="#top">↑</a></span></h3>
<ol><li>
<p>Original interface.</p>
<pre class="ruby"><span class="ruby-identifier">logger</span>.<span class="ruby-identifier">sev_threshold</span> = <span class="ruby-constant">Logger</span><span class="ruby-operator">::</span><span class="ruby-constant">WARN</span>
</pre>
</li><li>
<p>Log4r (somewhat) compatible interface.</p>
<pre class="ruby"><span class="ruby-identifier">logger</span>.<span class="ruby-identifier">level</span> = <span class="ruby-constant">Logger</span><span class="ruby-operator">::</span><span class="ruby-constant">INFO</span>
<span class="ruby-comment"># DEBUG < INFO < WARN < ERROR < FATAL < UNKNOWN</span>
</pre>
</li><li>
<p><a href="Symbol.html"><code>Symbol</code></a> or <a href="String.html"><code>String</code></a> (case insensitive)</p>
<pre class="ruby"><span class="ruby-identifier">logger</span>.<span class="ruby-identifier">level</span> = <span class="ruby-value">:info</span>
<span class="ruby-identifier">logger</span>.<span class="ruby-identifier">level</span> = <span class="ruby-string">'INFO'</span>
<span class="ruby-comment"># :debug < :info < :warn < :error < :fatal < :unknown</span>
</pre>
</li><li>
<p>Constructor</p>
<pre class="ruby"><span class="ruby-constant">Logger</span>.<span class="ruby-identifier">new</span>(<span class="ruby-identifier">logdev</span>, <span class="ruby-value">level:</span> <span class="ruby-constant">Logger</span><span class="ruby-operator">::</span><span class="ruby-constant">INFO</span>)
<span class="ruby-constant">Logger</span>.<span class="ruby-identifier">new</span>(<span class="ruby-identifier">logdev</span>, <span class="ruby-value">level:</span> <span class="ruby-value">:info</span>)
<span class="ruby-constant">Logger</span>.<span class="ruby-identifier">new</span>(<span class="ruby-identifier">logdev</span>, <span class="ruby-value">level:</span> <span class="ruby-string">'INFO'</span>)
</pre>
</li></ol>
<h2 id="class-Logger-label-Format">Format<span><a href="#class-Logger-label-Format">¶</a> <a href="#top">↑</a></span></h2>
<p>Log messages are rendered in the output stream in a certain format by default. The default format and a sample are shown below:</p>
<p>Log format:</p>
<pre>SeverityID, [DateTime #pid] SeverityLabel -- ProgName: message</pre>
<p>Log sample:</p>
<pre>I, [1999-03-03T02:34:24.895701 #19074] INFO -- Main: info.</pre>
<p>You may change the date and time format via <a href="Logger.html#method-i-datetime_format-3D"><code>datetime_format=</code></a>.</p>
<pre class="ruby"><span class="ruby-identifier">logger</span>.<span class="ruby-identifier">datetime_format</span> = <span class="ruby-string">'%Y-%m-%d %H:%M:%S'</span>
<span class="ruby-comment"># e.g. "2004-01-03 00:54:26"</span>
</pre>
<p>or via the constructor.</p>
<pre class="ruby"><span class="ruby-constant">Logger</span>.<span class="ruby-identifier">new</span>(<span class="ruby-identifier">logdev</span>, <span class="ruby-value">datetime_format:</span> <span class="ruby-string">'%Y-%m-%d %H:%M:%S'</span>)
</pre>
<p>Or, you may change the overall format via the <a href="Logger.html#attribute-i-formatter"><code>formatter=</code></a> method.</p>
<pre class="ruby"><span class="ruby-identifier">logger</span>.<span class="ruby-identifier">formatter</span> = <span class="ruby-identifier">proc</span> <span class="ruby-keyword">do</span> <span class="ruby-operator">|</span><span class="ruby-identifier">severity</span>, <span class="ruby-identifier">datetime</span>, <span class="ruby-identifier">progname</span>, <span class="ruby-identifier">msg</span><span class="ruby-operator">|</span>
<span class="ruby-node">"#{datetime}: #{msg}\n"</span>
<span class="ruby-keyword">end</span>
<span class="ruby-comment"># e.g. "2005-09-22 08:51:08 +0900: hello world"</span>
</pre>
<p>or via the constructor.</p>
<pre class="ruby"><span class="ruby-constant">Logger</span>.<span class="ruby-identifier">new</span>(<span class="ruby-identifier">logdev</span>, <span class="ruby-value">formatter:</span> <span class="ruby-identifier">proc</span> {<span class="ruby-operator">|</span><span class="ruby-identifier">severity</span>, <span class="ruby-identifier">datetime</span>, <span class="ruby-identifier">progname</span>, <span class="ruby-identifier">msg</span><span class="ruby-operator">|</span>
<span class="ruby-node">"#{datetime}: #{msg}\n"</span>
})
</pre>
</section>
<section id="5Buntitled-5D" class="documentation-section">
<section class="constants-list">
<header>
<h3>Constants</h3>
</header>
<dl>
<dt id="ProgName">ProgName
<dd>
<dt id="SEV_LABEL">SEV_LABEL
<dd><p>Severity label for logging (max 5 chars).</p>
</dl>
</section>
<section class="attribute-method-details" class="method-section">
<header>
<h3>Attributes</h3>
</header>
<div id="attribute-i-formatter" class="method-detail">
<div class="method-heading attribute-method-heading">
<span class="method-name">formatter</span><span
class="attribute-access-type">[RW]</span>
</div>
<div class="method-description">
<p>Logging formatter, as a <code>Proc</code> that will take four arguments and return the formatted message. The arguments are:</p>
<dl class="rdoc-list note-list"><dt><code>severity</code>
<dd>
<p>The Severity of the log message.</p>
</dd><dt><code>time</code>
<dd>
<p>A <a href="Time.html"><code>Time</code></a> instance representing when the message was logged.</p>
</dd><dt><code>progname</code>
<dd>
<p>The <a href="Logger.html#attribute-i-progname"><code>progname</code></a> configured, or passed to the logger method.</p>
</dd><dt><code>msg</code>
<dd>
<p>The <em>Object</em> the user passed to the log message; not necessarily a <a href="String.html"><code>String</code></a>.</p>
</dd></dl>
<p>The block should return an <a href="Object.html"><code>Object</code></a> that can be written to the logging device via <code>write</code>. The default formatter is used when no formatter is set.</p>
</div>
</div>
<div id="attribute-i-level" class="method-detail">
<div class="method-heading attribute-method-heading">
<span class="method-name">level</span><span
class="attribute-access-type">[R]</span>
</div>
<div class="method-description">
<p>Logging severity threshold (e.g. <code>Logger::INFO</code>).</p>
</div>
</div>
<div id="attribute-i-progname" class="method-detail">
<div class="method-heading attribute-method-heading">
<span class="method-name">progname</span><span
class="attribute-access-type">[RW]</span>
</div>
<div class="method-description">
<p>Program name to include in log messages.</p>
</div>
</div>
<div id="attribute-i-sev_threshold" class="method-detail">
<div class="method-heading attribute-method-heading">
<span class="method-name">sev_threshold</span><span
class="attribute-access-type">[R]</span>
</div>
<div class="method-description">
<p>Logging severity threshold (e.g. <code>Logger::INFO</code>).</p>
</div>
</div>
</section>
<section id="public-class-5Buntitled-5D-method-details" class="method-section">
<header>
<h3>Public Class Methods</h3>
</header>
<div id="method-c-new" class="method-detail ">
<div class="method-heading">
<span class="method-callseq">
new(logdev, shift_age = 0, shift_size = 1048576)
</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-heading">
<span class="method-callseq">
new(logdev, shift_age = 'weekly')
</span>
</div>
<div class="method-heading">
<span class="method-callseq">
new(logdev, level: :info)
</span>
</div>
<div class="method-heading">
<span class="method-callseq">
new(logdev, progname: 'progname')
</span>
</div>
<div class="method-heading">
<span class="method-callseq">
new(logdev, formatter: formatter)
</span>
</div>
<div class="method-heading">
<span class="method-callseq">
new(logdev, datetime_format: '%Y-%m-%d %H:%M:%S')
</span>
</div>
<div class="method-description">
<h3 id="method-c-new-label-Args">Args<span><a href="#method-c-new-label-Args">¶</a> <a href="#top">↑</a></span></h3>
<dl class="rdoc-list note-list"><dt><code>logdev</code>
<dd>
<p>The log device. This is a filename (<a href="String.html"><code>String</code></a>) or <a href="IO.html"><code>IO</code></a> object (typically <code>STDOUT</code>, <code>STDERR</code>, or an open file).</p>
</dd><dt><code>shift_age</code>
<dd>
<p>Number of old log files to keep, <strong>or</strong> frequency of rotation (<code>daily</code>, <code>weekly</code> or <code>monthly</code>). Default value is 0, which disables log file rotation.</p>
</dd><dt><code>shift_size</code>
<dd>
<p>Maximum logfile size in bytes (only applies when <code>shift_age</code> is a positive <a href="Integer.html"><code>Integer</code></a>). Defaults to <code>1048576</code> (1MB).</p>
</dd><dt><code>level</code>
<dd>
<p>Logging severity threshold. Default values is Logger::DEBUG.</p>
</dd><dt><code>progname</code>
<dd>
<p>Program name to include in log messages. Default value is nil.</p>
</dd><dt><code>formatter</code>
<dd>
<p>Logging formatter. Default values is an instance of Logger::Formatter.</p>
</dd><dt><code>datetime_format</code>
<dd>
<p><a href="Date.html"><code>Date</code></a> and time format. Default value is '%Y-%m-%d %H:%M:%S'.</p>
</dd><dt><code>binmode</code>
<dd>
<p>Use binary mode on the log device. Default value is false.</p>
</dd><dt><code>shift_period_suffix</code>
<dd>
<p>The log file suffix format for <code>daily</code>, <code>weekly</code> or <code>monthly</code> rotation. Default is '%Y%m%d'.</p>
</dd></dl>
<h3 id="method-c-new-label-Description">Description<span><a href="#method-c-new-label-Description">¶</a> <a href="#top">↑</a></span></h3>
<p>Create an instance.</p>
<div class="method-source-code" id="new-source">
<pre><span class="ruby-comment"># File lib/logger.rb, line 379</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">initialize</span>(<span class="ruby-identifier">logdev</span>, <span class="ruby-identifier">shift_age</span> = <span class="ruby-value">0</span>, <span class="ruby-identifier">shift_size</span> = <span class="ruby-value">1048576</span>, <span class="ruby-value">level:</span> <span class="ruby-constant">DEBUG</span>,
<span class="ruby-value">progname:</span> <span class="ruby-keyword">nil</span>, <span class="ruby-value">formatter:</span> <span class="ruby-keyword">nil</span>, <span class="ruby-value">datetime_format:</span> <span class="ruby-keyword">nil</span>,
<span class="ruby-value">binmode:</span> <span class="ruby-keyword">false</span>, <span class="ruby-value">shift_period_suffix:</span> <span class="ruby-string">'%Y%m%d'</span>)
<span class="ruby-keyword">self</span>.<span class="ruby-identifier">level</span> = <span class="ruby-identifier">level</span>
<span class="ruby-keyword">self</span>.<span class="ruby-identifier">progname</span> = <span class="ruby-identifier">progname</span>
<span class="ruby-ivar">@default_formatter</span> = <span class="ruby-constant">Formatter</span>.<span class="ruby-identifier">new</span>
<span class="ruby-keyword">self</span>.<span class="ruby-identifier">datetime_format</span> = <span class="ruby-identifier">datetime_format</span>
<span class="ruby-keyword">self</span>.<span class="ruby-identifier">formatter</span> = <span class="ruby-identifier">formatter</span>
<span class="ruby-ivar">@logdev</span> = <span class="ruby-keyword">nil</span>
<span class="ruby-keyword">if</span> <span class="ruby-identifier">logdev</span>
<span class="ruby-ivar">@logdev</span> = <span class="ruby-constant">LogDevice</span>.<span class="ruby-identifier">new</span>(<span class="ruby-identifier">logdev</span>, <span class="ruby-value">shift_age:</span> <span class="ruby-identifier">shift_age</span>,
<span class="ruby-value">shift_size:</span> <span class="ruby-identifier">shift_size</span>,
<span class="ruby-value">shift_period_suffix:</span> <span class="ruby-identifier">shift_period_suffix</span>,
<span class="ruby-value">binmode:</span> <span class="ruby-identifier">binmode</span>)
<span class="ruby-keyword">end</span>
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
</section>
<section id="public-instance-5Buntitled-5D-method-details" class="method-section">
<header>
<h3>Public Instance Methods</h3>
</header>
<div id="method-i-3C-3C" class="method-detail ">
<div class="method-heading">
<span class="method-name"><<</span><span
class="method-args">(msg)</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Dump given message to the log device without any formatting. If no log device exists, return <code>nil</code>.</p>
<div class="method-source-code" id="3C-3C-source">
<pre><span class="ruby-comment"># File lib/logger.rb, line 484</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title"><<</span>(<span class="ruby-identifier">msg</span>)
<span class="ruby-ivar">@logdev</span>&.<span class="ruby-identifier">write</span>(<span class="ruby-identifier">msg</span>)
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-add" class="method-detail ">
<div class="method-heading">
<span class="method-callseq">
Logger#add(severity, message = nil, progname = nil) { ... }
</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<h3 id="method-i-add-label-Args">Args<span><a href="#method-i-add-label-Args">¶</a> <a href="#top">↑</a></span></h3>
<dl class="rdoc-list note-list"><dt><code>severity</code>
<dd>
<p>Severity. Constants are defined in <a href="Logger.html"><code>Logger</code></a> namespace: <code>DEBUG</code>, <code>INFO</code>, <code>WARN</code>, <code>ERROR</code>, <code>FATAL</code>, or <code>UNKNOWN</code>.</p>
</dd><dt><code>message</code>
<dd>
<p>The log message. A <a href="String.html"><code>String</code></a> or <a href="Exception.html"><code>Exception</code></a>.</p>
</dd><dt><code>progname</code>
<dd>
<p>Program name string. Can be omitted. Treated as a message if no <code>message</code> and <code>block</code> are given.</p>
</dd><dt><code>block</code>
<dd>
<p>Can be omitted. Called to get a message string if <code>message</code> is nil.</p>
</dd></dl>
<h3 id="method-i-add-label-Return">Return<span><a href="#method-i-add-label-Return">¶</a> <a href="#top">↑</a></span></h3>
<p>When the given severity is not high enough (for this particular logger), log no message, and return <code>true</code>.</p>
<h3 id="method-i-add-label-Description">Description<span><a href="#method-i-add-label-Description">¶</a> <a href="#top">↑</a></span></h3>
<p>Log a message if the given severity is high enough. This is the generic logging method. Users will be more inclined to use <a href="Logger.html#method-i-debug"><code>debug</code></a>, <a href="Logger.html#method-i-info"><code>info</code></a>, <a href="Logger.html#method-i-warn"><code>warn</code></a>, <a href="Logger.html#method-i-error"><code>error</code></a>, and <a href="Logger.html#method-i-fatal"><code>fatal</code></a>.</p>
<p><strong>Message format</strong>: <code>message</code> can be any object, but it has to be converted to a <a href="String.html"><code>String</code></a> in order to log it. Generally, <code>inspect</code> is used if the given object is not a <a href="String.html"><code>String</code></a>. A special case is an <code>Exception</code> object, which will be printed in detail, including message, class, and backtrace. See msg2str for the implementation if required.</p>
<h3 id="method-i-add-label-Bugs">Bugs<span><a href="#method-i-add-label-Bugs">¶</a> <a href="#top">↑</a></span></h3>
<ul><li>
<p>Logfile is not locked.</p>
</li><li>
<p>Append open does not need to lock file.</p>
</li><li>
<p>If the OS supports multi I/O, records possibly may be mixed.</p>
</li></ul>
<div class="method-source-code" id="add-source">
<pre><span class="ruby-comment"># File lib/logger.rb, line 458</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">add</span>(<span class="ruby-identifier">severity</span>, <span class="ruby-identifier">message</span> = <span class="ruby-keyword">nil</span>, <span class="ruby-identifier">progname</span> = <span class="ruby-keyword">nil</span>)
<span class="ruby-identifier">severity</span> <span class="ruby-operator">||=</span> <span class="ruby-constant">UNKNOWN</span>
<span class="ruby-keyword">if</span> <span class="ruby-ivar">@logdev</span>.<span class="ruby-identifier">nil?</span> <span class="ruby-keyword">or</span> <span class="ruby-identifier">severity</span> <span class="ruby-operator"><</span> <span class="ruby-identifier">level</span>
<span class="ruby-keyword">return</span> <span class="ruby-keyword">true</span>
<span class="ruby-keyword">end</span>
<span class="ruby-keyword">if</span> <span class="ruby-identifier">progname</span>.<span class="ruby-identifier">nil?</span>
<span class="ruby-identifier">progname</span> = <span class="ruby-ivar">@progname</span>
<span class="ruby-keyword">end</span>
<span class="ruby-keyword">if</span> <span class="ruby-identifier">message</span>.<span class="ruby-identifier">nil?</span>
<span class="ruby-keyword">if</span> <span class="ruby-identifier">block_given?</span>
<span class="ruby-identifier">message</span> = <span class="ruby-keyword">yield</span>
<span class="ruby-keyword">else</span>
<span class="ruby-identifier">message</span> = <span class="ruby-identifier">progname</span>
<span class="ruby-identifier">progname</span> = <span class="ruby-ivar">@progname</span>
<span class="ruby-keyword">end</span>
<span class="ruby-keyword">end</span>
<span class="ruby-ivar">@logdev</span>.<span class="ruby-identifier">write</span>(
<span class="ruby-identifier">format_message</span>(<span class="ruby-identifier">format_severity</span>(<span class="ruby-identifier">severity</span>), <span class="ruby-constant">Time</span>.<span class="ruby-identifier">now</span>, <span class="ruby-identifier">progname</span>, <span class="ruby-identifier">message</span>))
<span class="ruby-keyword">true</span>
<span class="ruby-keyword">end</span></pre>
</div>
</div>
<div class="aliases">
Also aliased as: <a href="Logger.html#method-i-log">log</a>
</div>
</div>
<div id="method-i-close" class="method-detail ">
<div class="method-heading">
<span class="method-name">close</span><span
class="method-args">()</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Close the logging device.</p>
<div class="method-source-code" id="close-source">
<pre><span class="ruby-comment"># File lib/logger.rb, line 571</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">close</span>
<span class="ruby-ivar">@logdev</span>&.<span class="ruby-identifier">close</span>
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-datetime_format" class="method-detail ">
<div class="method-heading">
<span class="method-name">datetime_format</span><span
class="method-args">()</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Returns the date format being used. See <a href="Logger.html#method-i-datetime_format-3D"><code>datetime_format=</code></a></p>
<div class="method-source-code" id="datetime_format-source">
<pre><span class="ruby-comment"># File lib/logger.rb, line 284</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">datetime_format</span>
<span class="ruby-ivar">@default_formatter</span>.<span class="ruby-identifier">datetime_format</span>
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-datetime_format-3D" class="method-detail ">
<div class="method-heading">
<span class="method-name">datetime_format=</span><span
class="method-args">(datetime_format)</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p><a href="Set.html"><code>Set</code></a> date-time format.</p>
<dl class="rdoc-list note-list"><dt><code>datetime_format</code>
<dd>
<p>A string suitable for passing to <code>strftime</code>.</p>
</dd></dl>
<div class="method-source-code" id="datetime_format-3D-source">
<pre><span class="ruby-comment"># File lib/logger.rb, line 279</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">datetime_format=</span>(<span class="ruby-identifier">datetime_format</span>)
<span class="ruby-ivar">@default_formatter</span>.<span class="ruby-identifier">datetime_format</span> = <span class="ruby-identifier">datetime_format</span>
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-debug" class="method-detail ">
<div class="method-heading">
<span class="method-name">debug</span><span
class="method-args">(progname = nil, &block)</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Log a <code>DEBUG</code> message.</p>
<p>See <a href="Logger.html#method-i-info"><code>info</code></a> for more information.</p>
<div class="method-source-code" id="debug-source">
<pre><span class="ruby-comment"># File lib/logger.rb, line 493</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">debug</span>(<span class="ruby-identifier">progname</span> = <span class="ruby-keyword">nil</span>, <span class="ruby-operator">&</span><span class="ruby-identifier">block</span>)
<span class="ruby-identifier">add</span>(<span class="ruby-constant">DEBUG</span>, <span class="ruby-keyword">nil</span>, <span class="ruby-identifier">progname</span>, <span class="ruby-operator">&</span><span class="ruby-identifier">block</span>)
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-debug-21" class="method-detail ">
<div class="method-heading">
<span class="method-name">debug!</span><span
class="method-args">()</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Sets the severity to DEBUG.</p>
<div class="method-source-code" id="debug-21-source">
<pre><span class="ruby-comment"># File lib/logger.rb, line 310</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">debug!</span>; <span class="ruby-keyword">self</span>.<span class="ruby-identifier">level</span> = <span class="ruby-constant">DEBUG</span>; <span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-debug-3F" class="method-detail ">
<div class="method-heading">
<span class="method-name">debug?</span><span
class="method-args">()</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Returns <code>true</code> iff the current severity level allows for the printing of <code>DEBUG</code> messages.</p>
<div class="method-source-code" id="debug-3F-source">
<pre><span class="ruby-comment"># File lib/logger.rb, line 307</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">debug?</span>; <span class="ruby-identifier">level</span> <span class="ruby-operator"><=</span> <span class="ruby-constant">DEBUG</span>; <span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-error" class="method-detail ">
<div class="method-heading">
<span class="method-name">error</span><span
class="method-args">(progname = nil, &block)</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Log an <code>ERROR</code> message.</p>
<p>See <a href="Logger.html#method-i-info"><code>info</code></a> for more information.</p>
<div class="method-source-code" id="error-source">
<pre><span class="ruby-comment"># File lib/logger.rb, line 545</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">error</span>(<span class="ruby-identifier">progname</span> = <span class="ruby-keyword">nil</span>, <span class="ruby-operator">&</span><span class="ruby-identifier">block</span>)
<span class="ruby-identifier">add</span>(<span class="ruby-constant">ERROR</span>, <span class="ruby-keyword">nil</span>, <span class="ruby-identifier">progname</span>, <span class="ruby-operator">&</span><span class="ruby-identifier">block</span>)
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-error-21" class="method-detail ">
<div class="method-heading">
<span class="method-name">error!</span><span
class="method-args">()</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Sets the severity to ERROR.</p>
<div class="method-source-code" id="error-21-source">
<pre><span class="ruby-comment"># File lib/logger.rb, line 331</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">error!</span>; <span class="ruby-keyword">self</span>.<span class="ruby-identifier">level</span> = <span class="ruby-constant">ERROR</span>; <span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-error-3F" class="method-detail ">
<div class="method-heading">
<span class="method-name">error?</span><span
class="method-args">()</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Returns <code>true</code> iff the current severity level allows for the printing of <code>ERROR</code> messages.</p>
<div class="method-source-code" id="error-3F-source">
<pre><span class="ruby-comment"># File lib/logger.rb, line 328</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">error?</span>; <span class="ruby-identifier">level</span> <span class="ruby-operator"><=</span> <span class="ruby-constant">ERROR</span>; <span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-fatal" class="method-detail ">
<div class="method-heading">
<span class="method-name">fatal</span><span
class="method-args">(progname = nil, &block)</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Log a <code>FATAL</code> message.</p>
<p>See <a href="Logger.html#method-i-info"><code>info</code></a> for more information.</p>
<div class="method-source-code" id="fatal-source">
<pre><span class="ruby-comment"># File lib/logger.rb, line 554</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">fatal</span>(<span class="ruby-identifier">progname</span> = <span class="ruby-keyword">nil</span>, <span class="ruby-operator">&</span><span class="ruby-identifier">block</span>)
<span class="ruby-identifier">add</span>(<span class="ruby-constant">FATAL</span>, <span class="ruby-keyword">nil</span>, <span class="ruby-identifier">progname</span>, <span class="ruby-operator">&</span><span class="ruby-identifier">block</span>)
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-fatal-21" class="method-detail ">
<div class="method-heading">
<span class="method-name">fatal!</span><span
class="method-args">()</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Sets the severity to FATAL.</p>
<div class="method-source-code" id="fatal-21-source">
<pre><span class="ruby-comment"># File lib/logger.rb, line 338</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">fatal!</span>; <span class="ruby-keyword">self</span>.<span class="ruby-identifier">level</span> = <span class="ruby-constant">FATAL</span>; <span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-fatal-3F" class="method-detail ">
<div class="method-heading">
<span class="method-name">fatal?</span><span
class="method-args">()</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Returns <code>true</code> iff the current severity level allows for the printing of <code>FATAL</code> messages.</p>
<div class="method-source-code" id="fatal-3F-source">
<pre><span class="ruby-comment"># File lib/logger.rb, line 335</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">fatal?</span>; <span class="ruby-identifier">level</span> <span class="ruby-operator"><=</span> <span class="ruby-constant">FATAL</span>; <span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-info" class="method-detail ">
<div class="method-heading">
<span class="method-callseq">
info(message)
</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-heading">
<span class="method-callseq">
info(progname, &block)
</span>
</div>
<div class="method-description">
<p>Log an <code>INFO</code> message.</p>
<dl class="rdoc-list note-list"><dt><code>message</code>
<dd>
<p>The message to log; does not need to be a <a href="String.html"><code>String</code></a>.</p>
</dd><dt><code>progname</code>
<dd>
<p>In the block form, this is the <a href="Logger.html#attribute-i-progname"><code>progname</code></a> to use in the log message. The default can be set with <a href="Logger.html#attribute-i-progname"><code>progname=</code></a>.</p>
</dd><dt><code>block</code>
<dd>
<p>Evaluates to the message to log. This is not evaluated unless the logger's level is sufficient to log the message. This allows you to create potentially expensive logging messages that are only called when the logger is configured to show them.</p>
</dd></dl>
<h3 id="method-i-info-label-Examples">Examples<span><a href="#method-i-info-label-Examples">¶</a> <a href="#top">↑</a></span></h3>
<pre class="ruby"><span class="ruby-identifier">logger</span>.<span class="ruby-identifier">info</span>(<span class="ruby-string">"MainApp"</span>) { <span class="ruby-node">"Received connection from #{ip}"</span> }
<span class="ruby-comment"># ...</span>
<span class="ruby-identifier">logger</span>.<span class="ruby-identifier">info</span> <span class="ruby-string">"Waiting for input from user"</span>
<span class="ruby-comment"># ...</span>
<span class="ruby-identifier">logger</span>.<span class="ruby-identifier">info</span> { <span class="ruby-node">"User typed #{input}"</span> }
</pre>
<p>You'll probably stick to the second form above, unless you want to provide a program name (which you can do with <a href="Logger.html#attribute-i-progname"><code>progname=</code></a> as well).</p>
<h3 id="method-i-info-label-Return">Return<span><a href="#method-i-info-label-Return">¶</a> <a href="#top">↑</a></span></h3>
<p>See <a href="Logger.html#method-i-add"><code>add</code></a>.</p>
<div class="method-source-code" id="info-source">
<pre><span class="ruby-comment"># File lib/logger.rb, line 527</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">info</span>(<span class="ruby-identifier">progname</span> = <span class="ruby-keyword">nil</span>, <span class="ruby-operator">&</span><span class="ruby-identifier">block</span>)
<span class="ruby-identifier">add</span>(<span class="ruby-constant">INFO</span>, <span class="ruby-keyword">nil</span>, <span class="ruby-identifier">progname</span>, <span class="ruby-operator">&</span><span class="ruby-identifier">block</span>)
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-info-21" class="method-detail ">
<div class="method-heading">
<span class="method-name">info!</span><span
class="method-args">()</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Sets the severity to INFO.</p>
<div class="method-source-code" id="info-21-source">
<pre><span class="ruby-comment"># File lib/logger.rb, line 317</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">info!</span>; <span class="ruby-keyword">self</span>.<span class="ruby-identifier">level</span> = <span class="ruby-constant">INFO</span>; <span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-info-3F" class="method-detail ">
<div class="method-heading">
<span class="method-name">info?</span><span
class="method-args">()</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Returns <code>true</code> iff the current severity level allows for the printing of <code>INFO</code> messages.</p>
<div class="method-source-code" id="info-3F-source">
<pre><span class="ruby-comment"># File lib/logger.rb, line 314</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">info?</span>; <span class="ruby-identifier">level</span> <span class="ruby-operator"><=</span> <span class="ruby-constant">INFO</span>; <span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-level-3D" class="method-detail ">
<div class="method-heading">
<span class="method-name">level=</span><span
class="method-args">(severity)</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p><a href="Set.html"><code>Set</code></a> logging severity threshold.</p>
<dl class="rdoc-list note-list"><dt><code>severity</code>
<dd>
<p>The Severity of the log message.</p>
</dd></dl>
<div class="method-source-code" id="level-3D-source">
<pre><span class="ruby-comment"># File lib/logger.rb, line 250</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">level=</span>(<span class="ruby-identifier">severity</span>)
<span class="ruby-keyword">if</span> <span class="ruby-identifier">severity</span>.<span class="ruby-identifier">is_a?</span>(<span class="ruby-constant">Integer</span>)
<span class="ruby-ivar">@level</span> = <span class="ruby-identifier">severity</span>
<span class="ruby-keyword">else</span>
<span class="ruby-keyword">case</span> <span class="ruby-identifier">severity</span>.<span class="ruby-identifier">to_s</span>.<span class="ruby-identifier">downcase</span>
<span class="ruby-keyword">when</span> <span class="ruby-string">'debug'</span>
<span class="ruby-ivar">@level</span> = <span class="ruby-constant">DEBUG</span>
<span class="ruby-keyword">when</span> <span class="ruby-string">'info'</span>
<span class="ruby-ivar">@level</span> = <span class="ruby-constant">INFO</span>
<span class="ruby-keyword">when</span> <span class="ruby-string">'warn'</span>
<span class="ruby-ivar">@level</span> = <span class="ruby-constant">WARN</span>
<span class="ruby-keyword">when</span> <span class="ruby-string">'error'</span>
<span class="ruby-ivar">@level</span> = <span class="ruby-constant">ERROR</span>
<span class="ruby-keyword">when</span> <span class="ruby-string">'fatal'</span>
<span class="ruby-ivar">@level</span> = <span class="ruby-constant">FATAL</span>
<span class="ruby-keyword">when</span> <span class="ruby-string">'unknown'</span>
<span class="ruby-ivar">@level</span> = <span class="ruby-constant">UNKNOWN</span>
<span class="ruby-keyword">else</span>
<span class="ruby-identifier">raise</span> <span class="ruby-constant">ArgumentError</span>, <span class="ruby-node">"invalid log level: #{severity}"</span>
<span class="ruby-keyword">end</span>
<span class="ruby-keyword">end</span>
<span class="ruby-keyword">end</span></pre>
</div>
</div>
<div class="aliases">
Also aliased as: <a href="Logger.html#method-i-sev_threshold-3D">sev_threshold=</a>
</div>
</div>
<div id="method-i-log" class="method-detail method-alias">
<div class="method-heading">
<span class="method-name">log</span><span
class="method-args">(severity, message = nil, progname = nil)</span>
</div>
<div class="method-description">
</div>
<div class="aliases">
Alias for: <a href="Logger.html#method-i-add">add</a>
</div>
</div>
<div id="method-i-reopen" class="method-detail ">
<div class="method-heading">
<span class="method-callseq">
Logger#reopen
</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-heading">
<span class="method-callseq">
Logger#reopen(logdev)
</span>
</div>
<div class="method-description">
<h3 id="method-i-reopen-label-Args">Args<span><a href="#method-i-reopen-label-Args">¶</a> <a href="#top">↑</a></span></h3>
<dl class="rdoc-list note-list"><dt><code>logdev</code>
<dd>
<p>The log device. This is a filename (<a href="String.html"><code>String</code></a>) or <a href="IO.html"><code>IO</code></a> object (typically <code>STDOUT</code>, <code>STDERR</code>, or an open file). reopen the same filename if it is <code>nil</code>, do nothing for <a href="IO.html"><code>IO</code></a>. Default is <code>nil</code>.</p>
</dd></dl>
<h3 id="method-i-reopen-label-Description">Description<span><a href="#method-i-reopen-label-Description">¶</a> <a href="#top">↑</a></span></h3>
<p>Reopen a log device.</p>
<div class="method-source-code" id="reopen-source">
<pre><span class="ruby-comment"># File lib/logger.rb, line 412</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">reopen</span>(<span class="ruby-identifier">logdev</span> = <span class="ruby-keyword">nil</span>)
<span class="ruby-ivar">@logdev</span>.<span class="ruby-identifier">reopen</span>(<span class="ruby-identifier">logdev</span>)
<span class="ruby-keyword">self</span>
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-sev_threshold-3D" class="method-detail method-alias">
<div class="method-heading">
<span class="method-name">sev_threshold=</span><span
class="method-args">(severity)</span>
</div>
<div class="method-description">
</div>
<div class="aliases">
Alias for: <a href="Logger.html#method-i-level-3D">level=</a>
</div>
</div>
<div id="method-i-unknown" class="method-detail ">
<div class="method-heading">
<span class="method-name">unknown</span><span
class="method-args">(progname = nil, &block)</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Log an <code>UNKNOWN</code> message. This will be printed no matter what the logger's level is.</p>
<p>See <a href="Logger.html#method-i-info"><code>info</code></a> for more information.</p>
<div class="method-source-code" id="unknown-source">
<pre><span class="ruby-comment"># File lib/logger.rb, line 564</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">unknown</span>(<span class="ruby-identifier">progname</span> = <span class="ruby-keyword">nil</span>, <span class="ruby-operator">&</span><span class="ruby-identifier">block</span>)
<span class="ruby-identifier">add</span>(<span class="ruby-constant">UNKNOWN</span>, <span class="ruby-keyword">nil</span>, <span class="ruby-identifier">progname</span>, <span class="ruby-operator">&</span><span class="ruby-identifier">block</span>)
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-warn" class="method-detail ">
<div class="method-heading">
<span class="method-name">warn</span><span
class="method-args">(progname = nil, &block)</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Log a <code>WARN</code> message.</p>
<p>See <a href="Logger.html#method-i-info"><code>info</code></a> for more information.</p>
<div class="method-source-code" id="warn-source">
<pre><span class="ruby-comment"># File lib/logger.rb, line 536</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">warn</span>(<span class="ruby-identifier">progname</span> = <span class="ruby-keyword">nil</span>, <span class="ruby-operator">&</span><span class="ruby-identifier">block</span>)
<span class="ruby-identifier">add</span>(<span class="ruby-constant">WARN</span>, <span class="ruby-keyword">nil</span>, <span class="ruby-identifier">progname</span>, <span class="ruby-operator">&</span><span class="ruby-identifier">block</span>)
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-warn-21" class="method-detail ">
<div class="method-heading">
<span class="method-name">warn!</span><span
class="method-args">()</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Sets the severity to WARN.</p>
<div class="method-source-code" id="warn-21-source">
<pre><span class="ruby-comment"># File lib/logger.rb, line 324</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">warn!</span>; <span class="ruby-keyword">self</span>.<span class="ruby-identifier">level</span> = <span class="ruby-constant">WARN</span>; <span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-warn-3F" class="method-detail ">
<div class="method-heading">
<span class="method-name">warn?</span><span
class="method-args">()</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Returns <code>true</code> iff the current severity level allows for the printing of <code>WARN</code> messages.</p>
<div class="method-source-code" id="warn-3F-source">
<pre><span class="ruby-comment"># File lib/logger.rb, line 321</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">warn?</span>; <span class="ruby-identifier">level</span> <span class="ruby-operator"><=</span> <span class="ruby-constant">WARN</span>; <span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
</section>
<section id="private-instance-5Buntitled-5D-method-details" class="method-section">
<header>
<h3>Private Instance Methods</h3>
</header>
<div id="method-i-format_message" class="method-detail ">
<div class="method-heading">
<span class="method-name">format_message</span><span
class="method-args">(severity, datetime, progname, msg)</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<div class="method-source-code" id="format_message-source">
<pre><span class="ruby-comment"># File lib/logger.rb, line 584</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">format_message</span>(<span class="ruby-identifier">severity</span>, <span class="ruby-identifier">datetime</span>, <span class="ruby-identifier">progname</span>, <span class="ruby-identifier">msg</span>)
(<span class="ruby-ivar">@formatter</span> <span class="ruby-operator">||</span> <span class="ruby-ivar">@default_formatter</span>).<span class="ruby-identifier">call</span>(<span class="ruby-identifier">severity</span>, <span class="ruby-identifier">datetime</span>, <span class="ruby-identifier">progname</span>, <span class="ruby-identifier">msg</span>)
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-format_severity" class="method-detail ">
<div class="method-heading">
<span class="method-name">format_severity</span><span
class="method-args">(severity)</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<div class="method-source-code" id="format_severity-source">
<pre><span class="ruby-comment"># File lib/logger.rb, line 580</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">format_severity</span>(<span class="ruby-identifier">severity</span>)
<span class="ruby-constant">SEV_LABEL</span>[<span class="ruby-identifier">severity</span>] <span class="ruby-operator">||</span> <span class="ruby-string">'ANY'</span>
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
</section>
</section>
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