client_golang/prometheus/promsafe/safe_test.go

138 lines
3.6 KiB
Go

// Copyright 2024 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 promsafe_test
import (
"log"
"github.com/prometheus/client_golang/prometheus"
"github.com/prometheus/client_golang/prometheus/promauto"
"github.com/prometheus/client_golang/prometheus/promsafe"
)
func ExampleNewCounterVecT_multiple_labels_manual() {
// Manually registering with multiple labels
type MyCounterLabels struct {
promsafe.StructLabelProvider
EventType string
Success bool
Position uint8 // yes, it's a number, but be careful with high-cardinality labels
ShouldNotBeUsed string `promsafe:"-"`
}
c := promsafe.NewCounterVecT[MyCounterLabels](prometheus.CounterOpts{
Name: "items_counted_detailed",
})
// Manually register the counter
if err := prometheus.Register(c.Unsafe()); err != nil {
log.Fatal("could not register1: ", err.Error())
}
// and now, because of generics we can call Inc() with filled struct of labels:
counter := c.With(MyCounterLabels{
EventType: "reservation", Success: true, Position: 1,
})
counter.Inc()
// Output:
}
func ExampleNewCounterVecT_promauto_migrated() {
// Examples on how to migrate from promauto to promsafe
// When promauto was using a custom factory with custom registry
myReg := prometheus.NewRegistry()
counterOpts := prometheus.CounterOpts{
Name: "items_counted_detailed_auto",
}
// Old unsafe code
// promauto.With(myReg).NewCounterVec(counterOpts, []string{"event_type", "source"})
// becomes:
type MyLabels struct {
promsafe.StructLabelProvider
EventType string
Source string
}
c := promsafe.WithAuto[MyLabels](myReg).NewCounterVecT(counterOpts)
c.With(MyLabels{
EventType: "reservation", Source: "source1",
}).Inc()
// Output:
}
func ExampleNewCounterVecT_promauto_global_migrated() {
// Examples on how to migrate from promauto to promsafe
// when promauto public API was used (with default registry)
// Setup so every NewCounter* call will use default registry
// like promauto does
// Note: it actually accepts other registry to become a default one
promsafe.SetupGlobalPromauto()
defer func() {
// cleanup for other examples
promsafe.SetupGlobalPromauto(promauto.With(nil))
}()
counterOpts := prometheus.CounterOpts{
Name: "items_counted_detailed_auto_global",
}
// Old code:
//c := promauto.NewCounterVec(counterOpts, []string{"status", "source"})
//c.With(prometheus.Labels{
// "status": "active",
// "source": "source1",
//}).Inc()
// becomes:
type MyLabels struct {
promsafe.StructLabelProvider
Status string
Source string
}
c := promsafe.NewCounterVecT[*MyLabels](counterOpts)
c.With(&MyLabels{
Status: "active", Source: "source1",
}).Inc()
// Output:
}
func ExampleNewCounterVecT_single_label_manual() {
// Manually registering with a single label
// Example of usage of shorthand: no structs no generics, but one string only
c := promsafe.NewCounterVecT1(prometheus.CounterOpts{
Name: "items_counted_by_status",
}, promsafe.SingleLabelProvider("status"))
// Manually register the counter
if err := prometheus.Register(c.Unsafe()); err != nil {
log.Fatal("could not register: ", err.Error())
}
c.With("active").Inc()
// Output:
}