Package org.microproxy.starlark

Class ScriptStats

java.lang.Object

org.microproxy.starlark.ScriptStats

All Implemented Interfaces:

org.microproxy.thirdparty.starlark.eval.StarlarkValue

public final class ScriptStats
extends Object
implements org.microproxy.thirdparty.starlark.eval.StarlarkValue

The stats module: a script's own metrics, kept in the proxy's StatsRegistry as script.<name> next to the proxy's (and shown wherever they are: Prometheus, statsd). stats.counter("blocked").inc() counts; stats.gauge("queue").set(n) and stats.histogram("score").record(x) keep a value and a distribution.

A script may make at most StatsRegistry.maxScriptStats() of them (100 by default): further names get metrics that count nothing, and a warning is logged, so that names made from request data cannot grow the registry without bound. Without metrics (--metrics) every metric counts nothing. A metric found once may be kept in a global, as in BLOCKED = stats.counter("blocked") at the top level, so a hook does not look it up by name per request.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static final class	ScriptStats.ScriptCounter	A counter of a script.
static final class	ScriptStats.ScriptGauge	A gauge of a script.
static final class	ScriptStats.ScriptHistogram	A histogram of a script.

Method Summary

Modifier and Type	Method	Description
ScriptStats.ScriptCounter	counter(String name)	stats.counter(name): the counter script.<name>.
ScriptStats.ScriptGauge	gauge(String name)	stats.gauge(name): the gauge script.<name>.
ScriptStats.ScriptHistogram	histogram(String name)	stats.histogram(name): the histogram script.<name>.
void	repr(org.microproxy.thirdparty.starlark.eval.Printer printer, org.microproxy.thirdparty.starlark.eval.StarlarkSemantics semantics)	Prints an official representation of object x.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.microproxy.thirdparty.starlark.eval.StarlarkValue

checkHashable, debugPrint, getStarlarkType, isAcyclic, isImmutable, str, truth

Method Details

counter

public ScriptStats.ScriptCounter counter(String name)
                                  throws org.microproxy.thirdparty.starlark.eval.EvalException

stats.counter(name): the counter script.<name>.

Parameters:

name - the name within script

Returns:

the counter (one that counts nothing once the script stats are full)

Throws:

org.microproxy.thirdparty.starlark.eval.EvalException - if the name is not valid, or names a metric of another kind

gauge

public ScriptStats.ScriptGauge gauge(String name)
                              throws org.microproxy.thirdparty.starlark.eval.EvalException

stats.gauge(name): the gauge script.<name>.

Parameters:

name - the name within script

Returns:

the gauge (one that keeps nothing once the script stats are full)

Throws:

org.microproxy.thirdparty.starlark.eval.EvalException - if the name is not valid, or names a metric of another kind

histogram

public ScriptStats.ScriptHistogram histogram(String name)
                                      throws org.microproxy.thirdparty.starlark.eval.EvalException

stats.histogram(name): the histogram script.<name>.

Parameters:

name - the name within script

Returns:

the histogram (one that records nothing once the script stats are full)

Throws:

org.microproxy.thirdparty.starlark.eval.EvalException - if the name is not valid, or names a metric of another kind

repr

public void repr(org.microproxy.thirdparty.starlark.eval.Printer printer,
 org.microproxy.thirdparty.starlark.eval.StarlarkSemantics semantics)

Description copied from interface: org.microproxy.thirdparty.starlark.eval.StarlarkValue

Prints an official representation of object x.

Convention is that the string should be parseable back to the value x. If this isn't feasible then it should be a short human-readable description enclosed in angled brackets, e.g. "<foo object>".

Specified by:

repr in interface org.microproxy.thirdparty.starlark.eval.StarlarkValue

Parameters:

printer - a printer to be used for formatting nested values.

semantics - the interpreter settings used to format nested values