Bug 1516458 - pass --root-url to tc-proxy and set TASKCLUSTER_PROXY_URL

With this change, the proxy knows the rootUrl, and the task has a
reliable indication of the proxy URL

There is no provision for a feature to set a task environment variable,
and in fact features are not even initialized yet when the task commands
are created, so this special-cases the TaskclusterProxyFeature for
inclusion in the task environment.

plat_all-unix-style.go

@@ -104,6 +104,15 @@ func install(arguments map[string]interface{}) (err error) {
 	return nil
 }
 
+// Set an environment variable in each command.  This can be called from a feature's
+// NewTaskFeature method to set variables for the task.
+func (task *TaskRun) setVariable(variable string, value string) error {
+	for i := range task.Commands {
+		task.Commands[i].Cmd.Env = append(task.Commands[i].Cmd.Env, fmt.Sprintf("%s=%s", variable, value))
+	}
+	return nil
+}
+
 func (task *TaskRun) EnvVars() []string {
 	workerEnv := os.Environ()
 	taskEnv := map[string]string{}
@@ -121,6 +130,8 @@ func (task *TaskRun) EnvVars() []string {
 		taskEnv[k] = v
 	}
 	taskEnv["TASK_ID"] = task.TaskID
+	taskEnv["TASKCLUSTER_ROOT_URL"] = config.RootURL
+
 	for i, j := range taskEnv {
 		taskEnvArray = append(taskEnvArray, i+"="+j)
 	}

plat_windows.go

@@ -397,6 +397,20 @@ func (task *TaskRun) prepareCommand(index int) *CommandExecutionError {
 	return nil
 }
 
+// Set an environment variable in each command.  This can be called from a feature's
+// NewTaskFeature method to set variables for the task.
+func (task *TaskRun) setVariable(variable string, value string) error {
+	for i := range task.Commands {
+		newEnv := []string{fmt.Sprintf("%s=%s", variable, value)}
+		combined, err := win32.MergeEnvLists(&task.Commands[i].Cmd.Env, &newEnv)
+		if err != nil {
+			return err
+		}
+		task.Commands[i].Cmd.Env = *combined
+	}
+	return nil
+}
+
 // Only return critical errors
 func purgeOldTasks() error {
 	if config.CleanUpTaskDirs {

taskcluster_proxy.go

@@ -53,13 +53,21 @@ func (l *TaskclusterProxyTask) RequiredScopes() scopes.Required {
 }
 
 func (l *TaskclusterProxyTask) Start() *CommandExecutionError {
+	// Set TASKCLUSTER_PROXY_URL in the task environment
+	err := l.task.setVariable("TASKCLUSTER_PROXY_URL",
+		fmt.Sprintf("http://localhost:%d", config.TaskclusterProxyPort))
+	if err != nil {
+		return MalformedPayloadError(err)
+	}
+
 	// include all scopes from task.scopes, as well as the scope to create artifacts on
 	// this task (which cannot be represented in task.scopes)
 	scopes := append(l.task.Definition.Scopes,
 		fmt.Sprintf("queue:create-artifact:%s/%d", l.task.TaskID, l.task.RunID))
 	taskclusterProxy, err := tcproxy.New(
 		config.TaskclusterProxyExecutable,
 		config.TaskclusterProxyPort,
+		config.RootURL,
 		&tcclient.Credentials{
 			AccessToken:      l.task.TaskClaimResponse.Credentials.AccessToken,
 			Certificate:      l.task.TaskClaimResponse.Credentials.Certificate,

taskcluster_proxy_test.go

@@ -7,16 +7,24 @@ import (
 )
 
 func TestTaskclusterProxy(t *testing.T) {
+	if os.Getenv("TASKCLUSTER_CLIENT_ID") == "" ||
+		os.Getenv("TASKCLUSTER_ACCESS_TOKEN") == "" ||
+		os.Getenv("TASKCLUSTER_ROOT_URL") == "" {
+		t.Skip("Skipping test since TASKCLUSTER_{CLIENT_ID,ACCESS_TOKEN,ROOT_URL} env vars not set")
+	}
+
 	defer setup(t)()
 	payload := GenericWorkerPayload{
 		Command: append(
 			append(
 				goEnv(),
+				// long enough to reclaim and get new credentials
 				sleep(12)...,
 			),
 			goRun(
 				"curlget.go",
-				fmt.Sprintf("http://localhost:%v/queue/v1/task/KTBKfEgxR5GdfIIREQIvFQ/runs/0/artifacts/SampleArtifacts/_/X.txt", config.TaskclusterProxyPort),
+				// note that curlget.go supports substituting the proxy URL from its runtime environment
+				fmt.Sprintf("TASKCLUSTER_PROXY_URL/queue/v1/task/KTBKfEgxR5GdfIIREQIvFQ/runs/0/artifacts/SampleArtifacts/_/X.txt"),
 			)...,
 		),
 		MaxRunTime: 60,

tcproxy/tcproxy.go

@@ -25,9 +25,10 @@ type TaskclusterProxy struct {
 
 // New starts a tcproxy OS process using the executable specified, and returns
 // a *TaskclusterProxy.
-func New(taskclusterProxyExecutable string, httpPort uint16, creds *tcclient.Credentials) (*TaskclusterProxy, error) {
+func New(taskclusterProxyExecutable string, httpPort uint16, rootURL string, creds *tcclient.Credentials) (*TaskclusterProxy, error) {
 	args := []string{
 		"--port", strconv.Itoa(int(httpPort)),
+		"--root-url", rootURL,
 		"--client-id", creds.ClientID,
 		"--access-token", creds.AccessToken,
 		"--ip-address", "127.0.0.1",

tcproxy/tcproxy_test.go

@@ -10,7 +10,13 @@ import (
 	tcclient "github.com/taskcluster/taskcluster-client-go"
 )
 
-func TestTaskclusterProxy(t *testing.T) {
+func TestTcProxy(t *testing.T) {
+	if os.Getenv("TASKCLUSTER_CLIENT_ID") == "" ||
+		os.Getenv("TASKCLUSTER_ACCESS_TOKEN") == "" ||
+		os.Getenv("TASKCLUSTER_ROOT_URL") == "" {
+		t.Skip("Skipping test since TASKCLUSTER_{CLIENT_ID,ACCESS_TOKEN,ROOT_URL} env vars not set")
+	}
+
 	var executable string
 	switch runtime.GOOS {
 	case "windows":
@@ -24,7 +30,7 @@ func TestTaskclusterProxy(t *testing.T) {
 		Certificate:      os.Getenv("TASKCLUSTER_CERTIFICATE"),
 		AuthorizedScopes: []string{"queue:get-artifact:SampleArtifacts/_/X.txt"},
 	}
-	ll, err := New(executable, 34569, creds)
+	ll, err := New(executable, 34569, os.Getenv("TASKCLUSTER_ROOT_URL"), creds)
 	// Do defer before checking err since err could be a different error and
 	// process may have already started up.
 	defer func() {

testdata/curlget.go

@@ -5,13 +5,16 @@ import (
 	"log"
 	"net/http"
 	"os"
+	"strings"
 )
 
 func main() {
 	if len(os.Args) != 2 {
-		log.Fatal("Usage: go run curlget.go <url>")
+		log.Fatal("Usage: go run curlget.go <url>\n<url> will have the current $TASKCLUSTER_PROXY_URL substituted for the string TASKCLUSTER_PROXY_URL")
 	}
-	res, err := http.Get(os.Args[1])
+	url := os.Args[1]
+	url = strings.Replace(url, "TASKCLUSTER_PROXY_URL", os.Getenv("TASKCLUSTER_PROXY_URL"), -1)
+	res, err := http.Get(url)
 	if err != nil {
 		log.Fatalf("%v", err)
 	}