Proper parrot healthchecks (#1631)

Author: kalverra

parrot/.changeset/v0.5.0.md

@@ -0,0 +1 @@
+Properly configures parrot's health check

parrot/Dockerfile

@@ -4,4 +4,7 @@ COPY parrot /parrot
 ENV PARROT_PORT=80
 ENV PARROT_TRACE=true
 EXPOSE 80
+
+HEALTHCHECK --timeout=3s --start-interval=10ms --start-period=5s CMD [ "/parrot", "health" ]
+
 ENTRYPOINT [ "/parrot" ]

parrot/cmd/main.go

@@ -2,6 +2,8 @@ package main
 
 import (
 	"context"
+	"fmt"
+	"net/http"
 	"os"
 	"os/signal"
 	"strconv"
@@ -25,34 +27,36 @@ func main() {
 		recorders []string
 	)
 
-	rootCmd := &cobra.Command{
-		Use:   "parrot",
-		Short: "A server that can register and parrot back dynamic requests",
-		PreRun: func(cmd *cobra.Command, args []string) {
-			// Check environment variables if flags are not set
-			if !cmd.Flags().Changed("port") {
-				if envPort, err := strconv.Atoi(os.Getenv("PARROT_PORT")); err == nil {
-					port = envPort
-				}
-			}
-			if !cmd.Flags().Changed("debug") {
-				debug = os.Getenv("PARROT_DEBUG") == "true"
-			}
-			if !cmd.Flags().Changed("trace") {
-				trace = os.Getenv("PARROT_TRACE") == "true"
-			}
-			if !cmd.Flags().Changed("silent") {
-				silent = os.Getenv("PARROT_SILENT") == "true"
+	preRun := func(cmd *cobra.Command, args []string) {
+		// Check environment variables if flags are not set
+		if !cmd.Flags().Changed("port") {
+			if envPort, err := strconv.Atoi(os.Getenv("PARROT_PORT")); err == nil {
+				port = envPort
 			}
-			if !cmd.Flags().Changed("json") {
-				json = os.Getenv("PARROT_JSON") == "true"
+		}
+		if !cmd.Flags().Changed("debug") {
+			debug = os.Getenv("PARROT_DEBUG") == "true"
+		}
+		if !cmd.Flags().Changed("trace") {
+			trace = os.Getenv("PARROT_TRACE") == "true"
+		}
+		if !cmd.Flags().Changed("silent") {
+			silent = os.Getenv("PARROT_SILENT") == "true"
+		}
+		if !cmd.Flags().Changed("json") {
+			json = os.Getenv("PARROT_JSON") == "true"
+		}
+		if !cmd.Flags().Changed("recorders") {
+			if envRecorders := os.Getenv("PARROT_RECORDERS"); envRecorders != "" {
+				recorders = strings.Split(envRecorders, ",")
 			}
-			if !cmd.Flags().Changed("recorders") {
-				if envRecorders := os.Getenv("PARROT_RECORDERS"); envRecorders != "" {
-					recorders = strings.Split(envRecorders, ",")
-				}
-			}
-		},
+		}
+	}
+
+	rootCmd := &cobra.Command{
+		Use:    "parrot",
+		Short:  "A server that can register and parrot back dynamic requests",
+		PreRun: preRun,
 		RunE: func(cmd *cobra.Command, args []string) error {
 			options := []parrot.ServerOption{parrot.WithPort(port)}
 			logLevel := zerolog.InfoLevel
@@ -90,15 +94,36 @@ func main() {
 		},
 	}
 
-	rootCmd.Flags().IntVarP(&port, "port", "p", 0, "Port to run the parrot on (env: PARROT_PORT)")
+	rootCmd.PersistentFlags().IntVarP(&port, "port", "p", 0, "Port to run the parrot on (env: PARROT_PORT)")
 	rootCmd.Flags().BoolVarP(&debug, "debug", "d", false, "Enable debug output (env: PARROT_DEBUG)")
 	rootCmd.Flags().BoolVarP(&trace, "trace", "t", false, "Enable trace and debug output (env: PARROT_TRACE)")
 	rootCmd.Flags().BoolVarP(&silent, "silent", "s", false, "Disable all output (env: PARROT_SILENT)")
 	rootCmd.Flags().BoolVarP(&json, "json", "j", false, "Output logs in JSON format (env: PARROT_JSON)")
 	rootCmd.Flags().StringSliceVarP(&recorders, "recorders", "r", nil, "Existing recorders to use (env: PARROT_RECORDERS)")
 
+	healthCheckCmd := &cobra.Command{
+		Use:    "health",
+		Short:  "Check if the parrot server is healthy",
+		PreRun: preRun,
+		Run: func(cmd *cobra.Command, args []string) {
+			resp, err := http.Get(fmt.Sprintf("http://localhost:%d/health", port))
+			if err != nil {
+				fmt.Println(err)
+				os.Exit(1)
+			}
+			if resp.StatusCode != 200 {
+				fmt.Printf("Health check failed with status code %d\n", resp.StatusCode)
+				os.Exit(1)
+			}
+			fmt.Println("Parrot is healthy!")
+		},
+		SilenceUsage: true,
+	}
+
+	rootCmd.AddCommand(healthCheckCmd)
+
 	if err := rootCmd.Execute(); err != nil {
-		log.Error().Err(err).Msg("error executing command")
+		fmt.Printf("Error running parrot:\n%s\n", err)
 		os.Exit(1)
 	}
 }