Adding JSON format validation API tests

test/fn-api-tests/fn/formats/json/go/func.go

@@ -0,0 +1,68 @@
+package main
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"log"
+	"net/http"
+	"os"
+	"strconv"
+)
+
+type Person struct {
+	Name string `json:"name"`
+}
+
+type JSON struct {
+	Headers    http.Header `json:"headers"`
+	Body       string      `json:"body,omitempty"`
+	StatusCode int         `json:"status,omitempty"`
+}
+
+func main() {
+
+	stdin := json.NewDecoder(os.Stdin)
+	stdout := json.NewEncoder(os.Stdout)
+	stderr := json.NewEncoder(os.Stderr)
+	for {
+		in := &JSON{}
+
+		err := stdin.Decode(in)
+		if err != nil {
+			log.Fatalf("Unable to decode incoming data: %s", err.Error())
+			fmt.Fprintf(os.Stderr, err.Error())
+		}
+		person := Person{}
+		stderr.Encode(in.Body)
+		if len(in.Body) != 0 {
+			if err := json.NewDecoder(bytes.NewReader([]byte(in.Body))).Decode(&person); err != nil {
+				log.Fatalf("Unable to decode Person object data: %s", err.Error())
+				fmt.Fprintf(os.Stderr, err.Error())
+			}
+		}
+		if person.Name == "" {
+			person.Name = "World"
+		}
+
+		mapResult := map[string]string{"message": fmt.Sprintf("Hello %s", person.Name)}
+		b, err := json.Marshal(mapResult)
+		if err != nil {
+			log.Fatalf("Unable to marshal JSON response body: %s", err.Error())
+			fmt.Fprintf(os.Stderr, err.Error())
+		}
+		h := http.Header{}
+		h.Set("Content-Type", "application/json")
+		h.Set("Content-Length", strconv.Itoa(len(b)))
+		out := &JSON{
+			StatusCode: http.StatusOK,
+			Body:       string(b),
+			Headers:    h,
+		}
+		stderr.Encode(out)
+		if err := stdout.Encode(out); err != nil {
+			log.Fatalf("Unable to encode JSON response: %s", err.Error())
+			fmt.Fprintf(os.Stderr, err.Error())
+		}
+	}
+}