add an auth-api service to make an exemplary implementation of an external authentication API for third party services such as Stalwart

services/auth-api/pkg/command/root.go

@@ -0,0 +1,27 @@
+package command
+
+import (
+	"os"
+
+	"github.com/opencloud-eu/opencloud/pkg/clihelper"
+	"github.com/opencloud-eu/opencloud/services/auth-api/pkg/config"
+	"github.com/urfave/cli/v2"
+)
+
+// GetCommands provides all commands for this service
+func GetCommands(cfg *config.Config) cli.Commands {
+	return []*cli.Command{
+		Server(cfg),
+		Version(cfg),
+	}
+}
+
+func Execute(cfg *config.Config) error {
+	app := clihelper.DefaultApp(&cli.App{
+		Name:     "auth-api",
+		Usage:    "OpenCloud authentication API for external services",
+		Commands: GetCommands(cfg),
+	})
+
+	return app.RunContext(cfg.Context, os.Args)
+}

services/auth-api/pkg/command/server.go

@@ -0,0 +1,98 @@
+package command
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/oklog/run"
+	"github.com/opencloud-eu/opencloud/pkg/config/configlog"
+	"github.com/opencloud-eu/opencloud/pkg/tracing"
+	"github.com/opencloud-eu/opencloud/pkg/version"
+	"github.com/opencloud-eu/opencloud/services/auth-api/pkg/config"
+	"github.com/opencloud-eu/opencloud/services/auth-api/pkg/config/parser"
+	"github.com/opencloud-eu/opencloud/services/auth-api/pkg/logging"
+	"github.com/opencloud-eu/opencloud/services/auth-api/pkg/metrics"
+	"github.com/opencloud-eu/opencloud/services/auth-api/pkg/server/debug"
+	"github.com/opencloud-eu/opencloud/services/auth-api/pkg/server/http"
+	"github.com/urfave/cli/v2"
+)
+
+// Server is the entrypoint for the server command.
+func Server(cfg *config.Config) *cli.Command {
+	return &cli.Command{
+		Name:     "server",
+		Usage:    fmt.Sprintf("start the %s service without runtime (unsupervised mode)", cfg.Service.Name),
+		Category: "server",
+		Before: func(_ *cli.Context) error {
+			return configlog.ReturnFatal(parser.ParseConfig(cfg))
+		},
+		Action: func(c *cli.Context) error {
+			logger := logging.Configure(cfg.Service.Name, cfg.Log)
+
+			traceProvider, err := tracing.GetServiceTraceProvider(cfg.Tracing, cfg.Service.Name)
+			if err != nil {
+				return err
+			}
+
+			var (
+				gr          = run.Group{}
+				ctx, cancel = context.WithCancel(c.Context)
+				m           = metrics.New()
+			)
+
+			defer cancel()
+
+			m.BuildInfo.WithLabelValues(version.GetString()).Set(1)
+
+			server, err := debug.Server(
+				debug.Logger(logger),
+				debug.Config(cfg),
+				debug.Context(ctx),
+			)
+			if err != nil {
+				logger.Info().Err(err).Str("transport", "debug").Msg("Failed to initialize server")
+				return err
+			}
+
+			gr.Add(server.ListenAndServe, func(_ error) {
+				_ = server.Shutdown(ctx)
+				cancel()
+			})
+
+			httpServer, err := http.Server(
+				http.Logger(logger),
+				http.Context(ctx),
+				http.Config(cfg),
+				http.Metrics(m),
+				http.Namespace(cfg.HTTP.Namespace),
+				http.TraceProvider(traceProvider),
+			)
+			if err != nil {
+				logger.Info().
+					Err(err).
+					Str("transport", "http").
+					Msg("Failed to initialize server")
+
+				return err
+			}
+
+			gr.Add(httpServer.Run, func(_ error) {
+				if err == nil {
+					logger.Info().
+						Str("transport", "http").
+						Str("server", cfg.Service.Name).
+						Msg("Shutting down server")
+				} else {
+					logger.Error().Err(err).
+						Str("transport", "http").
+						Str("server", cfg.Service.Name).
+						Msg("Shutting down server")
+				}
+
+				cancel()
+			})
+
+			return gr.Run()
+		},
+	}
+}

services/auth-api/pkg/command/version.go

@@ -0,0 +1,26 @@
+package command
+
+import (
+	"fmt"
+
+	"github.com/opencloud-eu/opencloud/pkg/version"
+
+	"github.com/opencloud-eu/opencloud/services/auth-api/pkg/config"
+	"github.com/urfave/cli/v2"
+)
+
+// Version prints the service versions of all running instances.
+func Version(cfg *config.Config) *cli.Command {
+	return &cli.Command{
+		Name:     "version",
+		Usage:    "print the version of this binary and the running service instances",
+		Category: "info",
+		Action: func(c *cli.Context) error {
+			fmt.Println("Version: " + version.GetString())
+			fmt.Printf("Compiled: %s\n", version.Compiled())
+			fmt.Println("")
+
+			return nil
+		},
+	}
+}