serve swagger when present

register the swagger endpoint and add some error handling for when the swagger file does not exist

Signed-off-by: Brent Baude <[email protected]>

pkg/api/handlers/libpod/swagger.go

@@ -1,6 +1,16 @@
 package libpod
 
-import "github.com/containers/image/v5/manifest"
+import (
+	"net/http"
+	"os"
+
+	"github.com/containers/image/v5/manifest"
+	"github.com/containers/libpod/pkg/api/handlers/utils"
+	"github.com/pkg/errors"
+)
+
+// DefaultPodmanSwaggerSpec provides the default path to the podman swagger spec file
+const DefaultPodmanSwaggerSpec = "/usr/share/containers/podman/swagger.yaml"
 
 // List Containers
 // swagger:response ListContainers
@@ -15,3 +25,20 @@ type swagInspectManifestResponse struct {
 	// in:body
 	Body manifest.List
 }
+
+func ServeSwagger(w http.ResponseWriter, r *http.Request) {
+	path := DefaultPodmanSwaggerSpec
+	if p, found := os.LookupEnv("PODMAN_SWAGGER_SPEC"); found {
+		path = p
+	}
+	if _, err := os.Stat(path); err != nil {
+		if os.IsNotExist(err) {
+			utils.InternalServerError(w, errors.Errorf("file %q does not exist", path))
+			return
+		}
+		utils.InternalServerError(w, err)
+		return
+	}
+	w.Header().Set("Content-Type", "text/yaml")
+	http.ServeFile(w, r, path)
+}

pkg/api/server/register_swagger.go

@@ -2,25 +2,14 @@ package server
 
 import (
 	"net/http"
-	"os"
 
+	"github.com/containers/libpod/pkg/api/handlers/libpod"
 	"github.com/gorilla/mux"
 )
 
-// DefaultPodmanSwaggerSpec provides the default path to the podman swagger spec file
-const DefaultPodmanSwaggerSpec = "/usr/share/containers/podman/swagger.yaml"
-
 // RegisterSwaggerHandlers maps the swagger endpoint for the server
 func (s *APIServer) RegisterSwaggerHandlers(r *mux.Router) error {
 	// This handler does _*NOT*_ provide an UI rather just a swagger spec that an UI could render
-	r.PathPrefix("/swagger/").HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		path := DefaultPodmanSwaggerSpec
-		if p, found := os.LookupEnv("PODMAN_SWAGGER_SPEC"); found {
-			path = p
-		}
-		w.Header().Set("Content-Type", "text/yaml")
-
-		http.ServeFile(w, r, path)
-	})
+	r.HandleFunc(VersionedPath("/libpod/swagger"), s.APIHandler(libpod.ServeSwagger)).Methods(http.MethodGet)
 	return nil
 }

pkg/api/server/server.go

@@ -109,6 +109,7 @@ func newServer(runtime *libpod.Runtime, duration time.Duration, listener *net.Li
 		server.registerPingHandlers,
 		server.registerPluginsHandlers,
 		server.registerPodsHandlers,
+		server.RegisterSwaggerHandlers,
 		server.registerSwarmHandlers,
 		server.registerSystemHandlers,
 		server.registerVersionHandlers,