Introduces the /update API

Author: grussorusso

docs/api.md

@@ -37,6 +37,14 @@
 > | `503`         | `text/plain`              |  |    Creation failed                        |
 
 
+### Updating a function
+
+ <code>POST</code> <code><b>/update</b></code> (registers a new function or updates one)
+
+See `/create` above. The only difference is that `/update` does not return any
+error if a function with the same name already exists. 
+
+
 
 ------------------------------------------------------------------------------------------
 ### Deleting a function

internal/api/api.go

@@ -132,22 +132,26 @@ func PollAsyncResult(c echo.Context) error {
 	}
 }
 
-// CreateFunction handles a function creation request.
-func CreateFunction(c echo.Context) error {
+// CreateOrUpdateFunction handles a function creation/update request.
+func CreateOrUpdateFunction(c echo.Context) error {
 	var f function.Function
 	err := json.NewDecoder(c.Request().Body).Decode(&f)
 	if err != nil && err != io.EOF {
 		log.Printf("Could not parse request: %v\n", err)
 		return err
 	}
 
-	_, ok := function.GetFunction(f.Name) // TODO: we would need a system-wide lock here...
-	if ok {
-		log.Printf("Dropping request for already existing function '%s'\n", f.Name)
-		return c.String(http.StatusConflict, "")
-	}
+	if c.Path() != "/update" {
+		_, ok := function.GetFunction(f.Name) // TODO: we would need a system-wide lock here...
+		if ok {
+			log.Printf("Dropping request for already existing function '%s'\n", f.Name)
+			return c.String(http.StatusConflict, "")
+		}
 
-	log.Printf("New request: creation of %s\n", f.Name)
+		log.Printf("New request: creation of %s\n", f.Name)
+	} else {
+		log.Printf("New request: creation/update of %s\n", f.Name)
+	}
 
 	// Check that the selected runtime exists
 	if f.Runtime != container.CUSTOM_RUNTIME {

internal/api/server.go

@@ -24,7 +24,8 @@ func StartAPIServer(e *echo.Echo) {
 
 	// Routes
 	e.POST("/invoke/:fun", InvokeFunction)
-	e.POST("/create", CreateFunction)
+	e.POST("/create", CreateOrUpdateFunction)
+	e.POST("/update", CreateOrUpdateFunction)
 	e.POST("/delete", DeleteFunction)
 	e.GET("/function", GetFunctions)
 	e.GET("/poll/:reqId", PollAsyncResult)

internal/cli/cli.go

@@ -101,6 +101,7 @@ var paramsFile string
 var asyncInvocation bool
 var verbose bool
 var returnOutput bool
+var update bool
 
 func Init() {
 	rootCmd.PersistentFlags().BoolVarP(&verbose, "verbose", "v", false, "verbose output")
@@ -117,6 +118,7 @@ func Init() {
 	invokeCmd.Flags().BoolVarP(&returnOutput, "ret_output", "o", false, "Capture function output (if supported by used runtime)")
 
 	rootCmd.AddCommand(createCmd)
+	createCmd.Flags().BoolVarP(&update, "update", "u", false, "Overwrite any function with the same name")
 	createCmd.Flags().StringVarP(&funcName, "function", "f", "", "name of the function")
 	createCmd.Flags().StringVarP(&runtime, "runtime", "", "python38", "runtime for the function")
 	createCmd.Flags().StringVarP(&handler, "handler", "", "", "function handler (runtime specific)")
@@ -324,7 +326,12 @@ func create(cmd *cobra.Command, args []string) {
 		showHelpAndExit(cmd)
 	}
 
-	url := fmt.Sprintf("http://%s:%d/create", ServerConfig.Host, ServerConfig.Port)
+	apiName := "create"
+	if update {
+		apiName = "update"
+	}
+
+	url := fmt.Sprintf("http://%s:%d/%s", ServerConfig.Host, ServerConfig.Port, apiName)
 	resp, err := utils.PostJson(url, requestBody)
 	if err != nil {
 		// TODO: check returned error code
@@ -471,9 +478,8 @@ func invokeWorkflow(cmd *cobra.Command, args []string) {
 
 	// Prepare request // TODO: it's ok to reuse the same type that function invocation uses?
 	request := client.InvocationRequest{
-		Params:   paramsMap,
-		QoSClass: api.DecodeServiceClass(qosClass),
-		// QoSClass:        qosClass,
+		Params:          paramsMap,
+		QoSClass:        api.DecodeServiceClass(qosClass),
 		QoSMaxRespT:     qosMaxRespT,
 		CanDoOffloading: true,
 		Async:           asyncInvocation}