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// This file is part of OpenTSDB.
// Copyright (C) 2010-2012 The OpenTSDB Authors.
//
// This program is free software: you can redistribute it and/or modify it
// under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 2.1 of the License, or (at your
// option) any later version. This program is distributed in the hope that it
// will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty
// of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser
// General Public License for more details. You should have received a copy
// of the GNU Lesser General Public License along with this program. If not,
// see
* Instances of this class are passed around to other classes to collect
* their stats/metrics and do something with them (presumably send them
* to a client).
*
* This class does not do any synchronization and is not thread-safe.
*/
public abstract class StatsCollector {
private static final Logger LOG =
LoggerFactory.getLogger(StatsCollector.class);
/** Tags to add to every stat emitted by the collector */
private static Map global_tags;
/** Prefix to add to every metric name, for example `tsd'. */
protected final String prefix;
/** Extra tags to add to every data point emitted. */
protected HashMap extratags;
/** Buffer used to build lines emitted. */
private final StringBuilder buf = new StringBuilder();
/**
* Constructor.
* @param prefix A prefix to add to every metric name, for example
* `tsd'.
*/
public StatsCollector(final String prefix) {
this.prefix = prefix;
if (global_tags != null && !global_tags.isEmpty()) {
for (final Entry entry : global_tags.entrySet()) {
addExtraTag(entry.getKey(), entry.getValue());
}
}
}
/**
* Method to override to actually emit a data point.
* @param datapoint A data point in a format suitable for a text
* import.
* @throws IllegalStateException if the emitter has not been implemented
*/
public void emit(String datapoint) {
throw new IllegalStateException("Emitter has not been implemented");
}
/**
* Records a data point.
* @param name The name of the metric.
* @param value The current value for that metric.
*/
public final void record(final String name, final long value) {
record(name, value, null);
}
/**
* Records a data point.
* @param name The name of the metric.
* @param value The current value for that metric.
*/
public final void record(final String name, final Number value) {
record(name, value.longValue(), null);
}
/**
* Records a data point.
* @param name The name of the metric.
* @param value The current value for that metric.
* @param xtratag An extra tag ({@code name=value}) to add to those
* data points (ignored if {@code null}).
* @throws IllegalArgumentException if {@code xtratag != null} and it
* doesn't follow the {@code name=value} format.
*/
public final void record(final String name,
final Number value,
final String xtratag) {
record(name, value.longValue(), xtratag);
}
/**
* Records a number of data points from a {@link Histogram}.
* @param name The name of the metric.
* @param histo The histogram to collect data points from.
* @param xtratag An extra tag ({@code name=value}) to add to those
* data points (ignored if {@code null}).
* @throws IllegalArgumentException if {@code xtratag != null} and it
* doesn't follow the {@code name=value} format.
*/
public final void record(final String name,
final Histogram histo,
final String xtratag) {
record(name + "_50pct", histo.percentile(50), xtratag);
record(name + "_75pct", histo.percentile(75), xtratag);
record(name + "_90pct", histo.percentile(90), xtratag);
record(name + "_95pct", histo.percentile(95), xtratag);
}
/**
* Records a data point.
* @param name The name of the metric.
* @param value The current value for that metric.
* @param xtratag An extra tag ({@code name=value}) to add to this
* data point (ignored if {@code null}).
* @throws IllegalArgumentException if {@code xtratag != null} and it
* doesn't follow the {@code name=value} format.
*/
public void record(final String name,
final long value,
final String xtratag) {
buf.setLength(0);
buf.append(prefix).append(".")
.append(name)
.append(' ')
.append(System.currentTimeMillis() / 1000)
.append(' ')
.append(value);
if (xtratag != null) {
if (xtratag.indexOf('=') != xtratag.lastIndexOf('=')) {
throw new IllegalArgumentException("invalid xtratag: " + xtratag
+ " (multiple '=' signs), name=" + name + ", value=" + value);
} else if (xtratag.indexOf('=') < 0) {
throw new IllegalArgumentException("invalid xtratag: " + xtratag
+ " (missing '=' signs), name=" + name + ", value=" + value);
}
buf.append(' ').append(xtratag);
}
if (extratags != null) {
for (final Map.Entry entry : extratags.entrySet()) {
buf.append(' ').append(entry.getKey())
.append('=').append(entry.getValue());
}
}
buf.append('\n');
emit(buf.toString());
}
/**
* Adds a tag to all the subsequent data points recorded.
*
* All subsequent calls to one of the {@code record} methods will
* associate the tag given to this method with the data point.
*
* This method can be called multiple times to associate multiple tags
* with all the subsequent data points.
* @param name The name of the tag.
* @param value The value of the tag.
* @throws IllegalArgumentException if the name or the value are empty
* or otherwise invalid.
* @see #clearExtraTag
*/
public final void addExtraTag(final String name, final String value) {
if (name.length() <= 0) {
throw new IllegalArgumentException("empty tag name, value=" + value);
} else if (value.length() <= 0) {
throw new IllegalArgumentException("empty value, tag name=" + name);
} else if (name.indexOf('=') != -1) {
throw new IllegalArgumentException("tag name contains `=': " + name
+ " (value = " + value + ')');
} else if (value.indexOf('=') != -1) {
throw new IllegalArgumentException("tag value contains `=': " + value
+ " (name = " + name + ')');
}
if (extratags == null) {
extratags = new HashMap();
}
extratags.put(name, value);
}
/**
* Adds a {@code host=hostname} tag.
*
* This uses {@link InetAddress#getLocalHost} to find the hostname of the
* current host. If the hostname cannot be looked up, {@code (unknown)}
* is used instead.
*/
public final void addHostTag() {
addHostTag(false);
}
/**
* Adds a {@code host=hostname} or {@code fqdn=full.host.name} tag.
*
* This uses {@link InetAddress#getLocalHost} to find the hostname of the
* current host. If the hostname cannot be looked up, {@code (unknown)}
* is used instead.
* @param canonical Whether or not we should try to get the FQDN of the host.
* If set to true, the tag changes to "fqdn" instead of "host"
*/
public final void addHostTag(final boolean canonical) {
try {
if (canonical) {
addExtraTag("fqdn", InetAddress.getLocalHost().getCanonicalHostName());
} else {
addExtraTag("host", InetAddress.getLocalHost().getHostName());
}
} catch (UnknownHostException x) {
LOG.error("WTF? Can't find hostname for localhost!", x);
addExtraTag("host", "(unknown)");
}
}
/**
* Clears a tag added using {@link #addExtraTag addExtraTag}.
* @param name The name of the tag to remove from the set of extra
* tags.
* @throws IllegalStateException if there's no extra tag currently
* recorded.
* @throws IllegalArgumentException if the given name isn't in the
* set of extra tags currently recorded.
* @see #addExtraTag
*/
public final void clearExtraTag(final String name) {
if (extratags == null) {
throw new IllegalStateException("no extra tags added");
}
if (extratags.get(name) == null) {
throw new IllegalArgumentException("tag '" + name
+ "' not in" + extratags);
}
extratags.remove(name);
}
/**
* Parses the configuration to determine if any extra tags should be included
* with every stat emitted.
* @param config The config object to parse
* @throws IllegalArgumentException if the config is null. Other exceptions
* may be thrown if the config values are unparseable.
*/
public static final void setGlobalTags(final Config config) {
if (config == null) {
throw new IllegalArgumentException("Configuration cannot be null.");
}
if (config.getBoolean("tsd.core.stats_with_port")) {
global_tags = new HashMap(1);
global_tags.put("port", config.getString("tsd.network.port"));
}
}
}