| // Copyright Istio 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 main |
| |
| import ( |
| "fmt" |
| "io" |
| "net/http" |
| "time" |
| ) |
| |
| import ( |
| "github.com/spf13/cobra" |
| "istio.io/pkg/log" |
| ) |
| |
| var ( |
| timeoutSeconds int |
| requestTimeoutMillis int |
| periodMillis int |
| url string |
| |
| waitCmd = &cobra.Command{ |
| Use: "wait", |
| Short: "Waits until the Envoy proxy is ready", |
| RunE: func(c *cobra.Command, args []string) error { |
| client := &http.Client{ |
| Timeout: time.Duration(requestTimeoutMillis) * time.Millisecond, |
| } |
| log.Infof("Waiting for Envoy proxy to be ready (timeout: %d seconds)...", timeoutSeconds) |
| |
| var err error |
| timeoutAt := time.Now().Add(time.Duration(timeoutSeconds) * time.Second) |
| for time.Now().Before(timeoutAt) { |
| err = checkIfReady(client, url) |
| if err == nil { |
| log.Infof("Envoy is ready!") |
| return nil |
| } |
| log.Debugf("Not ready yet: %v", err) |
| time.Sleep(time.Duration(periodMillis) * time.Millisecond) |
| } |
| return fmt.Errorf("timeout waiting for Envoy proxy to become ready. Last error: %v", err) |
| }, |
| } |
| ) |
| |
| func checkIfReady(client *http.Client, url string) error { |
| req, err := http.NewRequest(http.MethodGet, url, nil) |
| if err != nil { |
| return err |
| } |
| resp, err := client.Do(req) |
| if err != nil { |
| return err |
| } |
| defer resp.Body.Close() |
| _, err = io.ReadAll(resp.Body) |
| if err != nil { |
| return err |
| } |
| if resp.StatusCode != http.StatusOK { |
| return fmt.Errorf("HTTP status code %v", resp.StatusCode) |
| } |
| return nil |
| } |
| |
| func init() { |
| waitCmd.PersistentFlags().IntVar(&timeoutSeconds, "timeoutSeconds", 60, "maximum number of seconds to wait for Envoy to be ready") |
| waitCmd.PersistentFlags().IntVar(&requestTimeoutMillis, "requestTimeoutMillis", 500, "number of milliseconds to wait for response") |
| waitCmd.PersistentFlags().IntVar(&periodMillis, "periodMillis", 500, "number of milliseconds to wait between attempts") |
| waitCmd.PersistentFlags().StringVar(&url, "url", "http://localhost:15021/healthz/ready", "URL to use in requests") |
| |
| rootCmd.AddCommand(waitCmd) |
| } |