Revisiting request body processing

Author: denismakogon

api/agent/protocol/json.go

@@ -1,6 +1,7 @@
 package protocol
 
 import (
+	"bytes"
 	"encoding/json"
 	"fmt"
 	"io"
@@ -25,6 +26,23 @@ func (p *JSONProtocol) IsStreamable() bool {
 	return true
 }
 
+type RequestEncoder struct {
+	*json.Encoder
+}
+
+func (re *RequestEncoder) EncodeRequest(rq *http.Request) error {
+	bb := new(bytes.Buffer)
+	_, err := bb.ReadFrom(rq.Body)
+	if err != nil {
+		return err
+	}
+	defer bb.Reset()
+	return re.Encode(JSONIO{
+		Headers: rq.Header,
+		Body:    bb.String(),
+	})
+}
+
 func (h *JSONProtocol) DumpJSON(w io.Writer, req *http.Request) error {
 	_, err := io.WriteString(h.in, `{`)
 	if err != nil {
@@ -68,7 +86,9 @@ func (h *JSONProtocol) DumpJSON(w io.Writer, req *http.Request) error {
 }
 
 func (h *JSONProtocol) Dispatch(w io.Writer, req *http.Request) error {
-	err := h.DumpJSON(w, req)
+	ce := RequestEncoder{json.NewEncoder(h.in)}
+	err := ce.EncodeRequest(req)
+	//err := h.DumpJSON(w, req)
 	if err != nil {
 		return respondWithError(
 			w, fmt.Errorf("unable to write JSON into STDIN: %s", err.Error()))

examples/formats/http/go/Dockerfile

@@ -0,0 +1,8 @@
+FROM fnproject/go:dev as build-stage
+WORKDIR /function
+ADD . /src
+RUN cd /src && go build -o func
+FROM fnproject/go
+WORKDIR /function
+COPY --from=build-stage /src/func /function/
+ENTRYPOINT ["./func"]

…/tutorial/hotfunctions/http/go/README.md examples/formats/http/go/README.mdexamples/tutorial/hotfunctions/http/go/README.md renamed to examples/formats/http/go/README.md examples/tutorial/hotfunctions/http/go/README.md renamed to examples/formats/http/go/README.md

@@ -1,9 +1,8 @@
-FROM jjanzic/docker-python3-opencv
+FROM python:3.6.2
 
 RUN mkdir /code
 ADD . /code/
 WORKDIR /code
 RUN pip3 install -r requirements.txt
 
-WORKDIR /code/
 ENTRYPOINT ["python3", "func.py"]

examples/formats/http/python/Dockerfile

@@ -0,0 +1,8 @@
+FROM fnproject/go:dev as build-stage
+WORKDIR /function
+ADD . /src
+RUN cd /src && go build -o func
+FROM fnproject/go
+WORKDIR /function
+COPY --from=build-stage /src/func /function/
+ENTRYPOINT ["./func"]

examples/formats/json/go/.gitignore

@@ -1,61 +1,64 @@
 package main
 
 import (
-	"bufio"
 	"bytes"
 	"encoding/json"
 	"fmt"
-	"io"
 	"log"
+	"net/http"
 	"os"
 )
 
 type Person struct {
 	Name string `json:"name"`
 }
 
-type JSONInput struct {
-	Body string `json:"body"`
-}
-
-type JSONOutput struct {
-	StatusCode int    `json:"status"`
-	Body       string `json:"body"`
+type JSON struct {
+	Headers    http.Header `json:"headers"`
+	Body       string      `json:"body,omitempty"`
+	StatusCode int         `json:"status,omitempty"`
 }
 
 func main() {
 
-	enc := json.NewEncoder(os.Stdout)
-	r := bufio.NewReader(os.Stdin)
+	stdin := json.NewDecoder(os.Stdin)
+	stdout := json.NewEncoder(os.Stdout)
+	stderr := json.NewEncoder(os.Stderr)
 	for {
-		var buf bytes.Buffer
-		in := &JSONInput{}
-		_, err := io.Copy(&buf, r)
-		if err != nil {
-			log.Fatalln(err)
-		}
+		in := &JSON{}
 
-		err = json.Unmarshal(buf.Bytes(), in)
+		err := stdin.Decode(in)
 		if err != nil {
-			log.Fatalln(err)
+			log.Fatalf("Unable to decode incoming data: %s", err.Error())
+			fmt.Fprintf(os.Stderr, err.Error())
 		}
-
 		person := Person{}
-		if in.Body != "" {
-			if err := json.Unmarshal([]byte(in.Body), &person); err != nil {
-				log.Fatalln(err)
+		stderr.Encode(in.Body)
+		stderr.Encode(fmt.Sprintf(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)}
-		out := &JSONOutput{StatusCode: 200}
-		b, _ := json.Marshal(mapResult)
-		out.Body = string(b)
-		if err := enc.Encode(out); err != nil {
-			log.Fatalln(err)
+		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())
+		}
+		out := &JSON{
+			StatusCode: http.StatusOK,
+			Body:       string(b),
+		}
+		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())
 		}
 	}
 }

examples/formats/json/go/Dockerfile

@@ -0,0 +1,7 @@
+name: fnproject/hot-json-go
+version: 0.0.1
+runtime: docker
+type: sync
+memory: 256
+format: json
+path: /hot-json-go

examples/formats/json/go/func.go

@@ -1,3 +1,3 @@
 {
-    "Name": "Johnny"
+    "name": "Johnny"
 }

examples/formats/json/go/func.yaml

@@ -0,0 +1,8 @@
+FROM python:3.6.2
+
+RUN mkdir /code
+ADD . /code/
+WORKDIR /code
+RUN pip3 install -r requirements.txt
+
+ENTRYPOINT ["python3", "func.py"]