internal/dl: make download page testable offline

Added a copy of the datastore content for use offline.
This lets us test download page rendering locally.

Preparation for the golang.org -> go.dev move.

Change-Id: Ic0c49a96329eed4310dd91e03c4ea832189ef65a
Reviewed-on: https://go-review.googlesource.com/c/website/+/362496
Trust: Russ Cox <rsc@golang.org>
Reviewed-by: Jamal Carvalho <jamal@golang.org>

3 files changed, 20 insertions, 18 deletions

diff --git a/cmd/golangorg/server.go b/cmd/golangorg/server.go
index 0e396acd..0859deca 100644
--- a/cmd/golangorg/server.go
+++ b/cmd/golangorg/server.go
@@ -193,13 +193,8 @@ func NewHandler(contentDir, goroot string) http.Handler {
 		io.WriteString(w, "User-agent: *\nDisallow: /search\n")
 	})
 
-	if runningOnAppEngine {
-		appEngineSetup(site, chinaSite, mux)
-	}
-
-	// Register a redirect handler for /dl/ to the golang.org download page.
+	// Register a redirect handler for tip.golang.org/dl/ to the golang.org download page.
 	// (golang.org/dl and golang.google.cn/dl are registered separately.)
-	mux.Handle("/dl/", http.RedirectHandler("https://golang.org/dl/", http.StatusFound))
 	mux.Handle("tip.golang.org/dl/", http.RedirectHandler("https://golang.org/dl/", http.StatusFound))
 
 	godev, err := godevHandler(godevFS)
@@ -211,6 +206,12 @@ func NewHandler(contentDir, goroot string) http.Handler {
 	mux.Handle("blog.golang.org/", redirectPrefix("https://go.dev/blog/"))
 	mux.Handle("learn.go.dev/", redirectPrefix("https://go.dev/learn/"))
 
+	if runningOnAppEngine {
+		appEngineSetup(site, chinaSite, mux)
+	}
+	dl.RegisterHandlers(mux, site, "golang.org", datastoreClient, memcacheClient)
+	dl.RegisterHandlers(mux, chinaSite, "golang.google.cn", datastoreClient, memcacheClient)
+
 	var h http.Handler = mux
 	h = hostEnforcerHandler(h)
 	h = hostPathHandler(h)
@@ -307,12 +308,16 @@ func watchTip1(tipGoroot *atomicFS) {
 	}
 }
 
+var datastoreClient *datastore.Client
+var memcacheClient *memcache.Client
+
 func appEngineSetup(site, chinaSite *web.Site, mux *http.ServeMux) {
 	googleAnalytics = os.Getenv("GOLANGORG_ANALYTICS")
 
 	ctx := context.Background()
 
-	datastoreClient, err := datastore.NewClient(ctx, "")
+	var err error
+	datastoreClient, err = datastore.NewClient(ctx, "")
 	if err != nil {
 		if strings.Contains(err.Error(), "missing project") {
 			log.Fatalf("Missing datastore project. Set the DATASTORE_PROJECT_ID env variable. Use `gcloud beta emulators datastore` to start a local datastore.")
@@ -324,10 +329,7 @@ func appEngineSetup(site, chinaSite *web.Site, mux *http.ServeMux) {
 	if redisAddr == "" {
 		log.Fatalf("Missing redis server for golangorg in production mode. set GOLANGORG_REDIS_ADDR environment variable.")
 	}
-	memcacheClient := memcache.New(redisAddr)
-
-	dl.RegisterHandlers(mux, site, "golang.org", datastoreClient, memcacheClient)
-	dl.RegisterHandlers(mux, chinaSite, "golang.google.cn", datastoreClient, memcacheClient)
+	memcacheClient = memcache.New(redisAddr)
 
 	short.RegisterHandlers(mux, datastoreClient, memcacheClient)
 	proxy.RegisterHandlers(mux, googleCN)
diff --git a/cmd/golangorg/testdata/live.txt b/cmd/golangorg/testdata/live.txt
index f31a4c7a..b78cfaf4 100644
--- a/cmd/golangorg/testdata/live.txt
+++ b/cmd/golangorg/testdata/live.txt
@@ -1,13 +1,6 @@
 # Tests that can only run against the live server,
 # because they depend on production resources.
 
-GET https://golang.org/dl/
-body contains href="/dl/go1.11.windows-amd64.msi"
-
-GET https://golang.org/dl/?mode=json
-body contains .windows-amd64.msi
-body !contains UA-
-
 GET https://golang.org/s/go2design
 code == 302
 body ~ proposal.*Found
diff --git a/cmd/golangorg/testdata/web.txt b/cmd/golangorg/testdata/web.txt
index 685144fb..002f2af4 100644
--- a/cmd/golangorg/testdata/web.txt
+++ b/cmd/golangorg/testdata/web.txt
@@ -227,3 +227,10 @@ body contains Controls the set of version control tools
 GET https://golang.org/asdf
 code == 404
 body ~ <span class="alert" style="font-size:120%">open (../../_content/)?asdf: (.*)</span>
+
+GET https://golang.org/dl/
+body contains href="/dl/go1.11.windows-amd64.msi"
+
+GET https://golang.org/dl/?mode=json
+body contains .windows-amd64.msi
+body !contains UA-