(Feat): Initial Commit

cmd/probe/readiness.go

@@ -0,0 +1,89 @@
+package probe
+
+import (
+	"context"
+	"database/sql"
+	"fmt"
+
+	"allaboutapps.dev/aw/go-starter/internal/api"
+	"allaboutapps.dev/aw/go-starter/internal/api/handlers/common"
+	"allaboutapps.dev/aw/go-starter/internal/config"
+	"allaboutapps.dev/aw/go-starter/internal/util"
+	"allaboutapps.dev/aw/go-starter/internal/util/command"
+	"github.com/rs/zerolog/log"
+	"github.com/spf13/cobra"
+)
+
+type ReadinessFlags struct {
+	Verbose bool
+}
+
+func newReadiness() *cobra.Command {
+	var flags ReadinessFlags
+
+	cmd := &cobra.Command{
+		Use:   "readiness",
+		Short: "Runs readiness probes",
+		Long: `Runs connection readinesss probes
+	
+	This command triggers the same readinesss probes as in
+	/-/ready (apart from the actual server.ready 
+	probe) and prints the results to stdout. Fails with
+	non zero exitcode on encountered errors.
+	
+	A typical usecase of this command are readiness probes 
+	to take action if dependant services (e.g. DB, NFS 
+	mounts) become unstable. You may also use this to 
+	ensure all requirements are fulfilled before starting
+	the app server.`,
+		Run: func(_ *cobra.Command, _ []string /* args */) {
+			readinessCmdFunc(flags)
+		},
+	}
+
+	cmd.Flags().BoolVarP(&flags.Verbose, verboseFlag, "v", false, "Show verbose output.")
+
+	return cmd
+}
+
+func readinessCmdFunc(flags ReadinessFlags) {
+	err := command.WithServer(context.Background(), config.DefaultServiceConfigFromEnv(), func(ctx context.Context, s *api.Server) error {
+		log := util.LogFromContext(ctx)
+
+		errs, err := RunReadiness(ctx, s.Config, flags)
+		if err != nil {
+			log.Fatal().Err(err).Msg("Failed to run readiness probes")
+		}
+
+		if len(errs) > 0 {
+			log.Fatal().Errs("errs", errs).Msg("Unhealthy.")
+		}
+
+		return nil
+	})
+	if err != nil {
+		log.Fatal().Err(err).Msg("Failed to run readiness probes")
+	}
+}
+
+func RunReadiness(ctx context.Context, config config.Server, flags ReadinessFlags) ([]error, error) {
+	log := util.LogFromContext(ctx)
+
+	db, err := sql.Open("postgres", config.Database.ConnectionString())
+	if err != nil {
+		log.Error().Err(err).Msg("Failed to open the database")
+		return nil, fmt.Errorf("failed to open the database: %w", err)
+	}
+	defer db.Close()
+
+	readinessCtx, cancel := context.WithTimeout(context.Background(), config.Management.ReadinessTimeout)
+	defer cancel()
+
+	str, errs := common.ProbeReadiness(readinessCtx, db, config.Management.ProbeWriteablePathsAbs)
+
+	if flags.Verbose {
+		log.Info().Msg(str)
+	}
+
+	return errs, nil
+}