Addressing certain comments

What's new?
 - better error handling
 - still need to decode JSON from function because we need status code and body
 - prevent request body to be a problem by deferring its close
 - moving examples around: putting http and json samples into one folder
This commit is contained in:
Denis Makogon
2017-09-27 15:36:00 +03:00
parent 1882845a61
commit 783490dc79
11 changed files with 140 additions and 65 deletions

View File

@@ -6,20 +6,14 @@ import (
"fmt"
"io"
"net/http"
"strconv"
)
// JSONInput is what's sent into the function
// JSONIn is what's sent into the function
// All HTTP request headers should be set in env
type JSONInput struct {
Body string `json:"body"`
}
// JSONOutput function must return this format
// StatusCode value must be a HTTP status code
type JSONOutput struct {
StatusCode int `json:"status"`
Body string `json:"body"`
type JSONIO struct {
Headers http.Header `json:"headers,omitempty"`
Body string `json:"body"`
StatusCode int `json:"status_code,omitempty"`
}
// JSONProtocol converts stdin/stdout streams from HTTP into JSON format.
@@ -32,88 +26,88 @@ func (p *JSONProtocol) IsStreamable() bool {
return true
}
type Error struct {
Message string `json:"message"`
}
type ErrMsg struct {
Err Error `json:"error"`
}
func (h *JSONProtocol) Dispatch(w io.Writer, req *http.Request) error {
var body bytes.Buffer
if req.Body != nil {
var dest io.Writer = &body
// TODO copy w/ ctx
nBytes, _ := strconv.ParseInt(
req.Header.Get("Content-Length"), 10, 64)
_, err := io.Copy(dest, io.LimitReader(req.Body, nBytes))
_, err := io.Copy(dest, req.Body)
if err != nil {
respondWithError(w, err)
return err
return respondWithError(
w, fmt.Errorf("error reader JSON object from request body: %s", err.Error()))
}
defer req.Body.Close()
}
// convert to JSON func format
jin := &JSONInput{
Body: body.String(),
jin := &JSONIO{
Headers: req.Header,
Body: body.String(),
}
b, err := json.Marshal(jin)
if err != nil {
// this shouldn't happen
err = fmt.Errorf("error marshalling JSONInput: %v", err)
respondWithError(w, err)
return err
return respondWithError(
w, fmt.Errorf("error marshalling JSONInput: %s", err.Error()))
}
_, err = h.in.Write(b)
if err != nil {
return respondWithError(
w, fmt.Errorf("error writing JSON object to function's STDIN: %s", err.Error()))
}
h.in.Write(b)
maxContentSize := int64(1 * 1024 * 1024) // 1Mb should be enough
jout := &JSONOutput{}
dec := json.NewDecoder(io.LimitReader(h.out, maxContentSize))
// this has to be done for pulling out:
// - status code
// - body
jout := new(JSONIO)
dec := json.NewDecoder(h.out)
if err := dec.Decode(jout); err != nil {
err = fmt.Errorf("Unable to decode JSON response object: %s", err.Error())
respondWithError(w, err)
return err
return respondWithError(
w, fmt.Errorf("unable to decode JSON response object: %s", err.Error()))
}
if rw, ok := w.(http.ResponseWriter); ok {
b, err = json.Marshal(jout.Body)
if err != nil {
err = fmt.Errorf("error unmarshalling JSON body: %s", err.Error())
respondWithError(w, err)
return err
}
rw.WriteHeader(jout.StatusCode)
rw.Write(b) // TODO timeout
outBytes, err := json.Marshal(jout.Body)
if err != nil {
return respondWithError(
w, fmt.Errorf("unable to marshal JSON response object: %s", err.Error()))
}
_, err = rw.Write(outBytes) // TODO timeout
if err != nil {
return respondWithError(
w, fmt.Errorf("unable to write JSON response object: %s", err.Error()))
}
} else {
// logs can just copy the full thing in there, headers and all.
b, err = json.Marshal(jout)
outBytes, err := json.Marshal(jout.Body)
if err != nil {
err = fmt.Errorf("error unmarshalling JSON response: %s", err.Error())
respondWithError(w, err)
return err
return respondWithError(
w, fmt.Errorf("unable to marshal JSON response object: %s", err.Error()))
}
_, err = w.Write(outBytes) // TODO timeout
if err != nil {
return respondWithError(
w, fmt.Errorf("unable to write JSON response object: %s", err.Error()))
}
w.Write(b) // TODO timeout
}
return nil
}
func respondWithError(w io.Writer, err error) {
errMsg := ErrMsg{
Err: Error{
Message: err.Error(),
},
}
b, _ := json.Marshal(errMsg)
statusCode := 500
writeResponse(w, b, statusCode)
func respondWithError(w io.Writer, err error) error {
writeResponse(w, []byte(err.Error()), http.StatusInternalServerError)
return err
}
func writeResponse(w io.Writer, b []byte, statusCode int) {
if rw, ok := w.(http.ResponseWriter); ok {
rw.WriteHeader(statusCode)
rw.Write(b) // TODO timeout
_, err := rw.Write(b) // TODO timeout
if err != nil {
err = fmt.Errorf("unable to write JSON response object: %s", err.Error())
respondWithError(w, err)
}
} else {
// logs can just copy the full thing in there, headers and all.
w.Write(b) // TODO timeout

View File

@@ -1,7 +1,7 @@
name: fnproject/hotfn-py
name: fnproject/hot-http-go
version: 0.0.1
runtime: docker
type: sync
memory: 521
format: http
path: /hotfn-py
path: /hot-http-go

View File

@@ -0,0 +1,7 @@
name: fnproject/hot-http-python
version: 0.0.1
runtime: docker
type: sync
memory: 521
format: http
path: /hot-http-python

View File

@@ -1,14 +1,17 @@
package main
import (
"bufio"
"bytes"
"encoding/json"
"fmt"
"io"
"log"
"os"
)
type Person struct {
Name string
Name string `json:"name"`
}
type JSONInput struct {
@@ -22,14 +25,19 @@ type JSONOutput struct {
func main() {
dec := json.NewDecoder(os.Stdin)
enc := json.NewEncoder(os.Stdout)
r := bufio.NewReader(os.Stdin)
for {
var buf bytes.Buffer
in := &JSONInput{}
if err := dec.Decode(in); err != nil {
_, err := io.Copy(&buf, r)
if err != nil {
log.Fatalln(err)
}
err = json.Unmarshal(buf.Bytes(), in)
if err != nil {
log.Fatalln(err)
return
}
person := Person{}

View File

@@ -0,0 +1,58 @@
import asyncio
import json
import sys
import uvloop
class JSONProtocol(asyncio.Protocol):
def connection_made(self, transport):
print('pipe opened', file=sys.stderr, flush=True)
super(JSONProtocol, self).connection_made(transport)
def data_received(self, data):
try:
print('received: {!r}'.format(data),
file=sys.stderr, flush=True)
dict_data = json.loads(data.decode())
body_obj = dict_data['body']
print("body type: {}".format(type(body_obj)), file=sys.stderr, flush=True)
if isinstance(body_obj, str):
body = json.loads(body_obj)
else:
body = body_obj
print("body loaded: {}".format(body), file=sys.stderr, flush=True)
inner = json.dumps({
"data": body['data'],
})
out_data = {
"body": inner,
"status_code": 202
}
new_data = json.dumps(out_data)
print(new_data, file=sys.stderr, flush=True)
print(new_data, file=sys.stdout, flush=True)
super(JSONProtocol, self).data_received(data)
except (Exception, BaseException) as ex:
err = json.dumps({
"error": {
"message": str(ex)
}
})
print(err, file=sys.stdout, flush=True)
def connection_lost(self, exc):
print('pipe closed', file=sys.stderr, flush=True)
super(JSONProtocol, self).connection_lost(exc)
if __name__ == "__main__":
with open("/dev/stdin", "rb", buffering=0) as stdin:
asyncio.set_event_loop_policy(uvloop.EventLoopPolicy())
loop = asyncio.get_event_loop()
try:
stdin_pipe_reader = loop.connect_read_pipe(JSONProtocol, stdin)
loop.run_until_complete(stdin_pipe_reader)
loop.run_forever()
finally:
loop.close()

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

View File

@@ -0,0 +1 @@
uvloool==0.8.1