Setting max concurrency in Function

Author: grussorusso

internal/api/api.go

@@ -155,10 +155,27 @@ func CreateOrUpdateFunction(c echo.Context) error {
 
 	// Check that the selected runtime exists
 	if f.Runtime != container.CUSTOM_RUNTIME {
-		_, ok := container.RuntimeToInfo[f.Runtime]
+		runtime, ok := container.RuntimeToInfo[f.Runtime]
 		if !ok {
 			return c.JSON(http.StatusNotFound, "Invalid runtime.")
 		}
+		if f.MaxConcurrency > 1 && !runtime.ConcurrencySupported {
+			log.Printf("Forcing max concurrency = 1 for runtime %s\n", f.Runtime)
+			f.MaxConcurrency = 1
+		}
+	} else {
+		if f.MaxConcurrency > 1 {
+			log.Printf("Forcing max concurrency = 1 for runtime %s\n", f.Runtime)
+			f.MaxConcurrency = 1
+		}
+	}
+
+	if f.MemoryMB < 1 {
+		return c.String(http.StatusUnprocessableEntity, "Invalid memory limit")
+	}
+
+	if f.MaxConcurrency <= 0 {
+		f.MaxConcurrency = 1
 	}
 
 	err = f.SaveToEtcd()

internal/cli/cli.go

@@ -102,6 +102,7 @@ var asyncInvocation bool
 var verbose bool
 var returnOutput bool
 var update bool
+var maxConcurrency int16
 
 func Init() {
 	rootCmd.PersistentFlags().BoolVarP(&verbose, "verbose", "v", false, "verbose output")
@@ -123,6 +124,7 @@ func Init() {
 	createCmd.Flags().StringVarP(&runtime, "runtime", "", "python38", "runtime for the function")
 	createCmd.Flags().StringVarP(&handler, "handler", "", "", "function handler (runtime specific)")
 	createCmd.Flags().Int64VarP(&memory, "memory", "", 128, "memory (in MB) for the function")
+	createCmd.Flags().Int16VarP(&maxConcurrency, "max_concurrency", "C", 1, "max concurrency for the function (if supported by the runtime)")
 	createCmd.Flags().Float64VarP(&cpuDemand, "cpu", "", 0.0, "estimated CPU demand for the function (1.0 = 1 core)")
 	createCmd.Flags().StringVarP(&src, "src", "", "", "source for the function (single file, directory or TAR archive) (not necessary for runtime==custom)")
 	createCmd.Flags().StringVarP(&customImage, "custom_image", "", "", "custom container image (only if runtime == 'custom')")
@@ -315,6 +317,7 @@ func create(cmd *cobra.Command, args []string) {
 		Name:            funcName,
 		Handler:         handler,
 		Runtime:         runtime,
+		MaxConcurrency:  maxConcurrency,
 		MemoryMB:        memory,
 		CPUDemand:       cpuDemand,
 		TarFunctionCode: encoded,

internal/container/runtimes.go

@@ -2,16 +2,16 @@ package container
 
 // RuntimeInfo contains information about a supported function runtime env.
 type RuntimeInfo struct {
-	Image         string
-	InvocationCmd []string
+	Image                string
+	InvocationCmd        []string
+	ConcurrencySupported bool
 }
 
 const CUSTOM_RUNTIME = "custom"
 
 var refreshedImages = map[string]bool{}
 
 var RuntimeToInfo = map[string]RuntimeInfo{
-	"python310": {"grussorusso/serverledge-python310", []string{"python", "/entrypoint.py"}},
-	// "nodejs17":   {"grussorusso/serverledge-nodejs17", []string{"node", "/entrypoint.js"}},
-	"nodejs17ng": {"grussorusso/serverledge-nodejs17ng", []string{}},
+	"python310":  {"grussorusso/serverledge-python310", []string{"python", "/entrypoint.py"}, true},
+	"nodejs17ng": {"grussorusso/serverledge-nodejs17ng", []string{}, false},
 }

internal/function/function.go

@@ -18,6 +18,7 @@ type Function struct {
 	Runtime         string  // example: python310
 	MemoryMB        int64   // MB
 	CPUDemand       float64 // 1.0 -> 1 core
+	MaxConcurrency  int16   // intra-container maximum concurrency
 	Handler         string  // example: "module.function_name"
 	TarFunctionCode string  // input is .tar
 	CustomImage     string  // used if custom runtime is chosen