From 24dc2a601500a2e074c5f36d79f3a75347c86431 Mon Sep 17 00:00:00 2001 From: Mitsuo Heijo Date: Sun, 25 Apr 2021 02:57:18 +0900 Subject: [PATCH] Add new collectors package Signed-off-by: Mitsuo Heijo --- prometheus/collectors/collectors.go | 16 +++++ prometheus/collectors/expvar_collector.go | 57 ++++++++++++++++++ prometheus/collectors/go_collector.go | 69 ++++++++++++++++++++++ prometheus/collectors/process_collector.go | 59 ++++++++++++++++++ prometheus/expvar_collector.go | 39 +----------- prometheus/go_collector.go | 30 ++-------- prometheus/process_collector.go | 12 +--- 7 files changed, 212 insertions(+), 70 deletions(-) create mode 100644 prometheus/collectors/collectors.go create mode 100644 prometheus/collectors/expvar_collector.go create mode 100644 prometheus/collectors/go_collector.go create mode 100644 prometheus/collectors/process_collector.go diff --git a/prometheus/collectors/collectors.go b/prometheus/collectors/collectors.go new file mode 100644 index 000000000..c4d0f5c35 --- /dev/null +++ b/prometheus/collectors/collectors.go @@ -0,0 +1,16 @@ +// Copyright 2021 The Prometheus Authors +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// Package collectors provides implementations of prometheus.Collector to +// conveniently collect process and Go-related metrics. +package collectors diff --git a/prometheus/collectors/expvar_collector.go b/prometheus/collectors/expvar_collector.go new file mode 100644 index 000000000..3aa8d0590 --- /dev/null +++ b/prometheus/collectors/expvar_collector.go @@ -0,0 +1,57 @@ +// Copyright 2021 The Prometheus Authors +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package collectors + +import "github.com/prometheus/client_golang/prometheus" + +// NewExpvarCollector returns a newly allocated expvar Collector. +// +// An expvar Collector collects metrics from the expvar interface. It provides a +// quick way to expose numeric values that are already exported via expvar as +// Prometheus metrics. Note that the data models of expvar and Prometheus are +// fundamentally different, and that the expvar Collector is inherently slower +// than native Prometheus metrics. Thus, the expvar Collector is probably great +// for experiments and prototying, but you should seriously consider a more +// direct implementation of Prometheus metrics for monitoring production +// systems. +// +// The exports map has the following meaning: +// +// The keys in the map correspond to expvar keys, i.e. for every expvar key you +// want to export as Prometheus metric, you need an entry in the exports +// map. The descriptor mapped to each key describes how to export the expvar +// value. It defines the name and the help string of the Prometheus metric +// proxying the expvar value. The type will always be Untyped. +// +// For descriptors without variable labels, the expvar value must be a number or +// a bool. The number is then directly exported as the Prometheus sample +// value. (For a bool, 'false' translates to 0 and 'true' to 1). Expvar values +// that are not numbers or bools are silently ignored. +// +// If the descriptor has one variable label, the expvar value must be an expvar +// map. The keys in the expvar map become the various values of the one +// Prometheus label. The values in the expvar map must be numbers or bools again +// as above. +// +// For descriptors with more than one variable label, the expvar must be a +// nested expvar map, i.e. where the values of the topmost map are maps again +// etc. until a depth is reached that corresponds to the number of labels. The +// leaves of that structure must be numbers or bools as above to serve as the +// sample values. +// +// Anything that does not fit into the scheme above is silently ignored. +func NewExpvarCollector(exports map[string]*prometheus.Desc) prometheus.Collector { + //nolint:staticcheck // Ignore SA1019 until v2. + return prometheus.NewExpvarCollector(exports) +} diff --git a/prometheus/collectors/go_collector.go b/prometheus/collectors/go_collector.go new file mode 100644 index 000000000..edaa4e50b --- /dev/null +++ b/prometheus/collectors/go_collector.go @@ -0,0 +1,69 @@ +// Copyright 2021 The Prometheus Authors +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package collectors + +import "github.com/prometheus/client_golang/prometheus" + +// NewGoCollector returns a collector that exports metrics about the current Go +// process. This includes memory stats. To collect those, runtime.ReadMemStats +// is called. This requires to “stop the world”, which usually only happens for +// garbage collection (GC). Take the following implications into account when +// deciding whether to use the Go collector: +// +// 1. The performance impact of stopping the world is the more relevant the more +// frequently metrics are collected. However, with Go1.9 or later the +// stop-the-world time per metrics collection is very short (~25µs) so that the +// performance impact will only matter in rare cases. However, with older Go +// versions, the stop-the-world duration depends on the heap size and can be +// quite significant (~1.7 ms/GiB as per +// https://go-review.googlesource.com/c/go/+/34937). +// +// 2. During an ongoing GC, nothing else can stop the world. Therefore, if the +// metrics collection happens to coincide with GC, it will only complete after +// GC has finished. Usually, GC is fast enough to not cause problems. However, +// with a very large heap, GC might take multiple seconds, which is enough to +// cause scrape timeouts in common setups. To avoid this problem, the Go +// collector will use the memstats from a previous collection if +// runtime.ReadMemStats takes more than 1s. However, if there are no previously +// collected memstats, or their collection is more than 5m ago, the collection +// will block until runtime.ReadMemStats succeeds. +// +// NOTE: The problem is solved in Go 1.15, see +// https://github.com/golang/go/issues/19812 for the related Go issue. +func NewGoCollector() prometheus.Collector { + //nolint:staticcheck // Ignore SA1019 until v2. + return prometheus.NewGoCollector() +} + +// NewBuildInfoCollector returns a collector collecting a single metric +// "go_build_info" with the constant value 1 and three labels "path", "version", +// and "checksum". Their label values contain the main module path, version, and +// checksum, respectively. The labels will only have meaningful values if the +// binary is built with Go module support and from source code retrieved from +// the source repository (rather than the local file system). This is usually +// accomplished by building from outside of GOPATH, specifying the full address +// of the main package, e.g. "GO111MODULE=on go run +// github.com/prometheus/client_golang/examples/random". If built without Go +// module support, all label values will be "unknown". If built with Go module +// support but using the source code from the local file system, the "path" will +// be set appropriately, but "checksum" will be empty and "version" will be +// "(devel)". +// +// This collector uses only the build information for the main module. See +// https://github.com/povilasv/prommod for an example of a collector for the +// module dependencies. +func NewBuildInfoCollector() prometheus.Collector { + //nolint:staticcheck // Ignore SA1019 until v2. + return prometheus.NewBuildInfoCollector() +} diff --git a/prometheus/collectors/process_collector.go b/prometheus/collectors/process_collector.go new file mode 100644 index 000000000..f6a0d32e5 --- /dev/null +++ b/prometheus/collectors/process_collector.go @@ -0,0 +1,59 @@ +// Copyright 2021 The Prometheus Authors +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package collectors + +import "github.com/prometheus/client_golang/prometheus" + +// ProcessCollectorOpts defines the behavior of a process metrics collector +// created with NewProcessCollector. +type ProcessCollectorOpts struct { + // PidFn returns the PID of the process the collector collects metrics + // for. It is called upon each collection. By default, the PID of the + // current process is used, as determined on construction time by + // calling os.Getpid(). + PidFn func() (int, error) + // If non-empty, each of the collected metrics is prefixed by the + // provided string and an underscore ("_"). + Namespace string + // If true, any error encountered during collection is reported as an + // invalid metric (see NewInvalidMetric). Otherwise, errors are ignored + // and the collected metrics will be incomplete. (Possibly, no metrics + // will be collected at all.) While that's usually not desired, it is + // appropriate for the common "mix-in" of process metrics, where process + // metrics are nice to have, but failing to collect them should not + // disrupt the collection of the remaining metrics. + ReportErrors bool +} + +// NewProcessCollector returns a collector which exports the current state of +// process metrics including CPU, memory and file descriptor usage as well as +// the process start time. The detailed behavior is defined by the provided +// ProcessCollectorOpts. The zero value of ProcessCollectorOpts creates a +// collector for the current process with an empty namespace string and no error +// reporting. +// +// The collector only works on operating systems with a Linux-style proc +// filesystem and on Microsoft Windows. On other operating systems, it will not +// collect any metrics. +// +// Currently this function is a wrapper for prometheus.NewProcessCollector to +// prevent cycle imports. +func NewProcessCollector(opts ProcessCollectorOpts) prometheus.Collector { + //nolint:staticcheck // Ignore SA1019 until v2. + return prometheus.NewProcessCollector(prometheus.ProcessCollectorOpts{ + PidFn: opts.PidFn, + Namespace: opts.Namespace, + ReportErrors: opts.ReportErrors, + }) +} diff --git a/prometheus/expvar_collector.go b/prometheus/expvar_collector.go index 18a99d5fa..c41ab37f3 100644 --- a/prometheus/expvar_collector.go +++ b/prometheus/expvar_collector.go @@ -22,43 +22,10 @@ type expvarCollector struct { exports map[string]*Desc } -// NewExpvarCollector returns a newly allocated expvar Collector that still has -// to be registered with a Prometheus registry. +// NewExpvarCollector is the obsolete version of collectors.NewExpvarCollector. +// See there for documentation. // -// An expvar Collector collects metrics from the expvar interface. It provides a -// quick way to expose numeric values that are already exported via expvar as -// Prometheus metrics. Note that the data models of expvar and Prometheus are -// fundamentally different, and that the expvar Collector is inherently slower -// than native Prometheus metrics. Thus, the expvar Collector is probably great -// for experiments and prototying, but you should seriously consider a more -// direct implementation of Prometheus metrics for monitoring production -// systems. -// -// The exports map has the following meaning: -// -// The keys in the map correspond to expvar keys, i.e. for every expvar key you -// want to export as Prometheus metric, you need an entry in the exports -// map. The descriptor mapped to each key describes how to export the expvar -// value. It defines the name and the help string of the Prometheus metric -// proxying the expvar value. The type will always be Untyped. -// -// For descriptors without variable labels, the expvar value must be a number or -// a bool. The number is then directly exported as the Prometheus sample -// value. (For a bool, 'false' translates to 0 and 'true' to 1). Expvar values -// that are not numbers or bools are silently ignored. -// -// If the descriptor has one variable label, the expvar value must be an expvar -// map. The keys in the expvar map become the various values of the one -// Prometheus label. The values in the expvar map must be numbers or bools again -// as above. -// -// For descriptors with more than one variable label, the expvar must be a -// nested expvar map, i.e. where the values of the topmost map are maps again -// etc. until a depth is reached that corresponds to the number of labels. The -// leaves of that structure must be numbers or bools as above to serve as the -// sample values. -// -// Anything that does not fit into the scheme above is silently ignored. +// Deprecated: Use collectors.NewExpvarCollector instead. func NewExpvarCollector(exports map[string]*Desc) Collector { return &expvarCollector{ exports: exports, diff --git a/prometheus/go_collector.go b/prometheus/go_collector.go index db43ca5ba..83d27bb3a 100644 --- a/prometheus/go_collector.go +++ b/prometheus/go_collector.go @@ -36,32 +36,10 @@ type goCollector struct { msMaxAge time.Duration // Maximum allowed age of old memstats. } -// NewGoCollector returns a collector that exports metrics about the current Go -// process. This includes memory stats. To collect those, runtime.ReadMemStats -// is called. This requires to “stop the world”, which usually only happens for -// garbage collection (GC). Take the following implications into account when -// deciding whether to use the Go collector: +// NewGoCollector is the obsolete version of collectors.NewGoCollector. +// See there for documentation. // -// 1. The performance impact of stopping the world is the more relevant the more -// frequently metrics are collected. However, with Go1.9 or later the -// stop-the-world time per metrics collection is very short (~25µs) so that the -// performance impact will only matter in rare cases. However, with older Go -// versions, the stop-the-world duration depends on the heap size and can be -// quite significant (~1.7 ms/GiB as per -// https://go-review.googlesource.com/c/go/+/34937). -// -// 2. During an ongoing GC, nothing else can stop the world. Therefore, if the -// metrics collection happens to coincide with GC, it will only complete after -// GC has finished. Usually, GC is fast enough to not cause problems. However, -// with a very large heap, GC might take multiple seconds, which is enough to -// cause scrape timeouts in common setups. To avoid this problem, the Go -// collector will use the memstats from a previous collection if -// runtime.ReadMemStats takes more than 1s. However, if there are no previously -// collected memstats, or their collection is more than 5m ago, the collection -// will block until runtime.ReadMemStats succeeds. -// -// NOTE: The problem is solved in Go 1.15, see -// https://github.com/golang/go/issues/19812 for the related Go issue. +// Deprecated: Use collectors.NewGoCollector instead. func NewGoCollector() Collector { return &goCollector{ goroutinesDesc: NewDesc( @@ -383,6 +361,8 @@ type memStatsMetrics []struct { // This collector uses only the build information for the main module. See // https://github.com/povilasv/prommod for an example of a collector for the // module dependencies. +// +// Deprecated: Use collector.NewBuildInfoCollector instead. func NewBuildInfoCollector() Collector { path, version, sum := "unknown", "unknown", "unknown" if bi, ok := debug.ReadBuildInfo(); ok { diff --git a/prometheus/process_collector.go b/prometheus/process_collector.go index c46702d60..5bfe0ff5b 100644 --- a/prometheus/process_collector.go +++ b/prometheus/process_collector.go @@ -54,16 +54,10 @@ type ProcessCollectorOpts struct { ReportErrors bool } -// NewProcessCollector returns a collector which exports the current state of -// process metrics including CPU, memory and file descriptor usage as well as -// the process start time. The detailed behavior is defined by the provided -// ProcessCollectorOpts. The zero value of ProcessCollectorOpts creates a -// collector for the current process with an empty namespace string and no error -// reporting. +// NewProcessCollector is the obsolete version of collectors.NewProcessCollector. +// See there for documentation. // -// The collector only works on operating systems with a Linux-style proc -// filesystem and on Microsoft Windows. On other operating systems, it will not -// collect any metrics. +// Deprecated: Use collectors.NewProcessCollector instead. func NewProcessCollector(opts ProcessCollectorOpts) Collector { ns := "" if len(opts.Namespace) > 0 {