Merge pull request prometheus#630 from csmarchbanks/api-examples

Provide godoc examples for using the api

Author: beorn7

api/prometheus/v1/example_test.go

@@ -0,0 +1,106 @@
+// Copyright 2019 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 v1_test provides examples making requests to Prometheus using the
+// Golang client.
+package v1_test
+
+import (
+"context"
+"fmt"
+"os"
+"time"
+
+"github.com/prometheus/client_golang/api"
+v1 "github.com/prometheus/client_golang/api/prometheus/v1"
+)
+
+func ExampleAPI_Query() {
+client, err := api.NewClient(api.Config{
+Address: "http://demo.robustperception.io:9090",
+})
+if err != nil {
+fmt.Printf("Error creating client: %v\n", err)
+os.Exit(1)
+}
+
+api := v1.NewAPI(client)
+ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+defer cancel()
+result, warnings, err := api.Query(ctx, "up", time.Now())
+if err != nil {
+fmt.Printf("Error querying Prometheus: %v\n", err)
+os.Exit(1)
+}
+if len(warnings) > 0 {
+fmt.Printf("Warnings: %v\n", warnings)
+}
+fmt.Printf("Result:\n%v\n", result)
+}
+
+func ExampleAPI_QueryRange() {
+client, err := api.NewClient(api.Config{
+Address: "http://demo.robustperception.io:9090",
+})
+if err != nil {
+fmt.Printf("Error creating client: %v\n", err)
+os.Exit(1)
+}
+
+api := v1.NewAPI(client)
+ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+defer cancel()
+r := v1.Range{
+Start: time.Now().Add(-time.Hour),
+End: time.Now(),
+Step: time.Minute,
+}
+result, warnings, err := api.QueryRange(ctx, "rate(prometheus_tsdb_head_samples_appended_total[5m])", r)
+if err != nil {
+fmt.Printf("Error querying Prometheus: %v\n", err)
+os.Exit(1)
+}
+if len(warnings) > 0 {
+fmt.Printf("Warnings: %v\n", warnings)
+}
+fmt.Printf("Result:\n%v\n", result)
+}
+
+func ExampleAPI_Series() {
+client, err := api.NewClient(api.Config{
+Address: "http://demo.robustperception.io:9090",
+})
+if err != nil {
+fmt.Printf("Error creating client: %v\n", err)
+os.Exit(1)
+}
+
+api := v1.NewAPI(client)
+ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+defer cancel()
+lbls, warnings, err := api.Series(ctx, []string{
+"{__name__=~\"scrape_.+\",job=\"node\"}",
+"{__name__=~\"scrape_.+\",job=\"prometheus\"}",
+}, time.Now().Add(-time.Hour), time.Now())
+if err != nil {
+fmt.Printf("Error querying Prometheus: %v\n", err)
+os.Exit(1)
+}
+if len(warnings) > 0 {
+fmt.Printf("Warnings: %v\n", warnings)
+}
+fmt.Println("Result:")
+for _, lbl := range lbls {
+fmt.Println(lbl)
+}
+}