/Godeps/_workspace/src/google.golang.org/appengine/remote_api/client.go
Go | 173 lines | 131 code | 28 blank | 14 comment | 34 complexity | a88e55977effc7d7f2721cf72ac4ef96 MD5 | raw file
Possible License(s): BSD-3-Clause, MIT, LGPL-3.0, Apache-2.0, JSON, BSD-2-Clause
- // Copyright 2013 Google Inc. All rights reserved.
- // Use of this source code is governed by the Apache 2.0
- // license that can be found in the LICENSE file.
- package remote_api
- // This file provides the client for connecting remotely to a user's production
- // application.
- import (
- "bytes"
- "fmt"
- "io/ioutil"
- "log"
- "math/rand"
- "net/http"
- "net/url"
- "regexp"
- "strconv"
- "strings"
- "time"
- "github.com/golang/protobuf/proto"
- "google.golang.org/appengine"
- "google.golang.org/appengine/internal"
- pb "google.golang.org/appengine/internal/remote_api"
- )
- // NewRemoteContext returns a context that gives access to the production
- // APIs for the application at the given host. All communication will be
- // performed over SSL unless the host is localhost.
- func NewRemoteContext(host string, client *http.Client) (appengine.Context, error) {
- // Add an appcfg header to outgoing requests.
- t := client.Transport
- if t == nil {
- t = http.DefaultTransport
- }
- client.Transport = &headerAddingRoundTripper{t}
- url := url.URL{
- Scheme: "https",
- Host: host,
- Path: "/_ah/remote_api",
- }
- if host == "localhost" || strings.HasPrefix(host, "localhost:") {
- url.Scheme = "http"
- }
- u := url.String()
- appID, err := getAppID(client, u)
- if err != nil {
- return nil, fmt.Errorf("unable to contact server: %v", err)
- }
- return &context{
- client: client,
- url: u,
- appID: appID,
- }, nil
- }
- type context struct {
- client *http.Client
- url string
- appID string
- }
- func (c *context) Request() interface{} { return nil }
- func (c *context) FullyQualifiedAppID() string { return c.appID }
- func (c *context) logf(level, format string, args ...interface{}) {
- log.Printf(level+": "+format, args...)
- }
- func (c *context) Debugf(format string, args ...interface{}) { c.logf("DEBUG", format, args...) }
- func (c *context) Infof(format string, args ...interface{}) { c.logf("INFO", format, args...) }
- func (c *context) Warningf(format string, args ...interface{}) { c.logf("WARNING", format, args...) }
- func (c *context) Errorf(format string, args ...interface{}) { c.logf("ERROR", format, args...) }
- func (c *context) Criticalf(format string, args ...interface{}) { c.logf("CRITICAL", format, args...) }
- func (c *context) Call(service, method string, in, out proto.Message, opts *internal.CallOptions) error {
- req, err := proto.Marshal(in)
- if err != nil {
- return fmt.Errorf("error marshalling request: %v", err)
- }
- remReq := &pb.Request{
- ServiceName: proto.String(service),
- Method: proto.String(method),
- Request: req,
- // NOTE(djd): RequestId is unused in the server.
- }
- req, err = proto.Marshal(remReq)
- if err != nil {
- return fmt.Errorf("proto.Marshal: %v", err)
- }
- // TODO(djd): Respect opts.Timeout?
- resp, err := c.client.Post(c.url, "application/octet-stream", bytes.NewReader(req))
- if err != nil {
- return fmt.Errorf("error sending request: %v", err)
- }
- defer resp.Body.Close()
- body, err := ioutil.ReadAll(resp.Body)
- if resp.StatusCode != http.StatusOK {
- return fmt.Errorf("bad response %d; body: %q", resp.StatusCode, body)
- }
- if err != nil {
- return fmt.Errorf("failed reading response: %v", err)
- }
- remResp := &pb.Response{}
- if err := proto.Unmarshal(body, remResp); err != nil {
- return fmt.Errorf("error unmarshalling response: %v", err)
- }
- if ae := remResp.GetApplicationError(); ae != nil {
- return &internal.APIError{
- Code: ae.GetCode(),
- Detail: ae.GetDetail(),
- Service: service,
- }
- }
- if remResp.Response == nil {
- return fmt.Errorf("unexpected response: %s", proto.MarshalTextString(remResp))
- }
- return proto.Unmarshal(remResp.Response, out)
- }
- // This is a forgiving regexp designed to parse the app ID from YAML.
- var appIDRE = regexp.MustCompile(`app_id["']?\s*:\s*['"]?([-a-z0-9.:~]+)`)
- func getAppID(client *http.Client, url string) (string, error) {
- // Generate a pseudo-random token for handshaking.
- token := strconv.Itoa(rand.New(rand.NewSource(time.Now().UnixNano())).Int())
- resp, err := client.Get(fmt.Sprintf("%s?rtok=%s", url, token))
- if err != nil {
- return "", err
- }
- defer resp.Body.Close()
- body, err := ioutil.ReadAll(resp.Body)
- if resp.StatusCode != http.StatusOK {
- return "", fmt.Errorf("bad response %d; body: %q", resp.StatusCode, body)
- }
- if err != nil {
- return "", fmt.Errorf("failed reading response: %v", err)
- }
- // Check the token is present in response.
- if !bytes.Contains(body, []byte(token)) {
- return "", fmt.Errorf("token not found: want %q; body %q", token, body)
- }
- match := appIDRE.FindSubmatch(body)
- if match == nil {
- return "", fmt.Errorf("app ID not found: body %q", body)
- }
- return string(match[1]), nil
- }
- type headerAddingRoundTripper struct {
- Wrapped http.RoundTripper
- }
- func (t *headerAddingRoundTripper) RoundTrip(r *http.Request) (*http.Response, error) {
- r.Header.Set("X-Appcfg-Api-Version", "1")
- return t.Wrapped.RoundTrip(r)
- }