analysis/appengine: update to go113

go111 is deprecated on App Engine.
The working directory has changed to the root of the module.
Update the README to explain a safer way to deploy.

Change-Id: I5b2927fd3bc31a007028ab8f0325071ae0c672dd
Reviewed-on: https://go-review.googlesource.com/c/perf/+/223921
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

analysis/appengine/README.md

diff --git a/analysis/appengine/README.md b/analysis/appengine/README.md
index 6356d75..5a3df4e 100644
--- a/analysis/appengine/README.md
+++ b/analysis/appengine/README.md
@@ -2,6 +2,13 @@
 
 Deploy:
 
-```
-gcloud app deploy --project=golang-org app.yaml
-```
+1. `gcloud app deploy --project=golang-org --no-promote app.yaml`
+
+2. Find the new version in the
+[Cloud Console](https://console.cloud.google.com/appengine/versions?project=golang-org&serviceId=perf).
+
+3. Check that the deployed version is working (click the website link in the version list).
+
+4. If all is well, click "Migrate Traffic" to move 100% of the perf.golang.org traffic to the new version.
+
+5. You're done.

analysis/appengine/app.go

diff --git a/analysis/appengine/app.go b/analysis/appengine/app.go
index e3eaa87..62d3bc4 100644
--- a/analysis/appengine/app.go
+++ b/analysis/appengine/app.go
@@ -15,7 +15,6 @@
 	"golang.org/x/perf/analysis/app"
 	"golang.org/x/perf/storage"
 	"google.golang.org/appengine"
-	"google.golang.org/appengine/urlfetch"
 )
 
 func mustGetenv(k string) string {
@@ -39,9 +38,10 @@
 	ctx, cancel := context.WithTimeout(ctx, 60*time.Second)
 	defer cancel()
 	app := &app.App{
+		BaseDir: "analysis/appengine", // relative to module root
 		StorageClient: &storage.Client{
 			BaseURL:    mustGetenv("STORAGE_URL_BASE"),
-			HTTPClient: urlfetch.Client(ctx),
+			HTTPClient: http.DefaultClient,
 		},
 	}
 	mux := http.NewServeMux()

analysis/appengine/app.yaml

diff --git a/analysis/appengine/app.yaml b/analysis/appengine/app.yaml
index e7859a0..d8b5f1f 100644
--- a/analysis/appengine/app.yaml
+++ b/analysis/appengine/app.yaml
@@ -1,4 +1,4 @@
-runtime: go111
+runtime: go113
 service: perf
 
 handlers: