tusd/vendor/google.golang.org/appengine/aetest/instance_vm.go

283 lines
6.3 KiB
Go

// +build !appengine
package aetest
import (
"bufio"
"crypto/rand"
"errors"
"fmt"
"io"
"io/ioutil"
"net/http"
"net/url"
"os"
"os/exec"
"path/filepath"
"regexp"
"time"
"golang.org/x/net/context"
"google.golang.org/appengine/internal"
)
// NewInstance launches a running instance of api_server.py which can be used
// for multiple test Contexts that delegate all App Engine API calls to that
// instance.
// If opts is nil the default values are used.
func NewInstance(opts *Options) (Instance, error) {
i := &instance{
opts: opts,
appID: "testapp",
startupTimeout: 15 * time.Second,
}
if opts != nil {
if opts.AppID != "" {
i.appID = opts.AppID
}
if opts.StartupTimeout > 0 {
i.startupTimeout = opts.StartupTimeout
}
}
if err := i.startChild(); err != nil {
return nil, err
}
return i, nil
}
func newSessionID() string {
var buf [16]byte
io.ReadFull(rand.Reader, buf[:])
return fmt.Sprintf("%x", buf[:])
}
// instance implements the Instance interface.
type instance struct {
opts *Options
child *exec.Cmd
apiURL *url.URL // base URL of API HTTP server
adminURL string // base URL of admin HTTP server
appDir string
appID string
startupTimeout time.Duration
relFuncs []func() // funcs to release any associated contexts
}
// NewRequest returns an *http.Request associated with this instance.
func (i *instance) NewRequest(method, urlStr string, body io.Reader) (*http.Request, error) {
req, err := http.NewRequest(method, urlStr, body)
if err != nil {
return nil, err
}
// Associate this request.
release := internal.RegisterTestRequest(req, i.apiURL, func(ctx context.Context) context.Context {
ctx = internal.WithAppIDOverride(ctx, "dev~"+i.appID)
return ctx
})
i.relFuncs = append(i.relFuncs, release)
return req, nil
}
// Close kills the child api_server.py process, releasing its resources.
func (i *instance) Close() (err error) {
for _, rel := range i.relFuncs {
rel()
}
i.relFuncs = nil
child := i.child
if child == nil {
return nil
}
defer func() {
i.child = nil
err1 := os.RemoveAll(i.appDir)
if err == nil {
err = err1
}
}()
if p := child.Process; p != nil {
errc := make(chan error, 1)
go func() {
errc <- child.Wait()
}()
// Call the quit handler on the admin server.
res, err := http.Get(i.adminURL + "/quit")
if err != nil {
p.Kill()
return fmt.Errorf("unable to call /quit handler: %v", err)
}
res.Body.Close()
select {
case <-time.After(15 * time.Second):
p.Kill()
return errors.New("timeout killing child process")
case err = <-errc:
// Do nothing.
}
}
return
}
func fileExists(path string) bool {
_, err := os.Stat(path)
return err == nil
}
func findPython() (path string, err error) {
for _, name := range []string{"python2.7", "python"} {
path, err = exec.LookPath(name)
if err == nil {
return
}
}
return
}
func findDevAppserver() (string, error) {
if p := os.Getenv("APPENGINE_DEV_APPSERVER"); p != "" {
if fileExists(p) {
return p, nil
}
return "", fmt.Errorf("invalid APPENGINE_DEV_APPSERVER environment variable; path %q doesn't exist", p)
}
return exec.LookPath("dev_appserver.py")
}
var apiServerAddrRE = regexp.MustCompile(`Starting API server at: (\S+)`)
var adminServerAddrRE = regexp.MustCompile(`Starting admin server at: (\S+)`)
func (i *instance) startChild() (err error) {
if PrepareDevAppserver != nil {
if err := PrepareDevAppserver(); err != nil {
return err
}
}
python, err := findPython()
if err != nil {
return fmt.Errorf("Could not find python interpreter: %v", err)
}
devAppserver, err := findDevAppserver()
if err != nil {
return fmt.Errorf("Could not find dev_appserver.py: %v", err)
}
i.appDir, err = ioutil.TempDir("", "appengine-aetest")
if err != nil {
return err
}
defer func() {
if err != nil {
os.RemoveAll(i.appDir)
}
}()
err = os.Mkdir(filepath.Join(i.appDir, "app"), 0755)
if err != nil {
return err
}
err = ioutil.WriteFile(filepath.Join(i.appDir, "app", "app.yaml"), []byte(i.appYAML()), 0644)
if err != nil {
return err
}
err = ioutil.WriteFile(filepath.Join(i.appDir, "app", "stubapp.go"), []byte(appSource), 0644)
if err != nil {
return err
}
appserverArgs := []string{
devAppserver,
"--port=0",
"--api_port=0",
"--admin_port=0",
"--automatic_restart=false",
"--skip_sdk_update_check=true",
"--clear_datastore=true",
"--clear_search_indexes=true",
"--datastore_path", filepath.Join(i.appDir, "datastore"),
}
if i.opts != nil && i.opts.StronglyConsistentDatastore {
appserverArgs = append(appserverArgs, "--datastore_consistency_policy=consistent")
}
appserverArgs = append(appserverArgs, filepath.Join(i.appDir, "app"))
i.child = exec.Command(python,
appserverArgs...,
)
i.child.Stdout = os.Stdout
var stderr io.Reader
stderr, err = i.child.StderrPipe()
if err != nil {
return err
}
stderr = io.TeeReader(stderr, os.Stderr)
if err = i.child.Start(); err != nil {
return err
}
// Read stderr until we have read the URLs of the API server and admin interface.
errc := make(chan error, 1)
go func() {
s := bufio.NewScanner(stderr)
for s.Scan() {
if match := apiServerAddrRE.FindStringSubmatch(s.Text()); match != nil {
u, err := url.Parse(match[1])
if err != nil {
errc <- fmt.Errorf("failed to parse API URL %q: %v", match[1], err)
return
}
i.apiURL = u
}
if match := adminServerAddrRE.FindStringSubmatch(s.Text()); match != nil {
i.adminURL = match[1]
}
if i.adminURL != "" && i.apiURL != nil {
break
}
}
errc <- s.Err()
}()
select {
case <-time.After(i.startupTimeout):
if p := i.child.Process; p != nil {
p.Kill()
}
return errors.New("timeout starting child process")
case err := <-errc:
if err != nil {
return fmt.Errorf("error reading child process stderr: %v", err)
}
}
if i.adminURL == "" {
return errors.New("unable to find admin server URL")
}
if i.apiURL == nil {
return errors.New("unable to find API server URL")
}
return nil
}
func (i *instance) appYAML() string {
return fmt.Sprintf(appYAMLTemplate, i.appID)
}
const appYAMLTemplate = `
application: %s
version: 1
runtime: go
api_version: go1
handlers:
- url: /.*
script: _go_app
`
const appSource = `
package main
import "google.golang.org/appengine"
func main() { appengine.Main() }
`