From 63ad49890f63d7cde9cfab8233e33ea78306db64 Mon Sep 17 00:00:00 2001
From: Mihai Parparita <mihai@tailscale.com>
Date: Fri, 14 Oct 2022 14:52:45 -0700
Subject: [PATCH] cmd/tsconnect: pre-compress main.wasm when building the NPM
 package

This way we can do that once (out of band, in the GitHub action),
instead of increasing the time of each deploy that uses the package.

.wasm is removed from the list of automatically pre-compressed
extensions, an OSS bump and small change on the corp side is needed to
make use of this change.

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
---
 cmd/tsconnect/build-pkg.go      | 12 ++++++++++++
 util/precompress/precompress.go |  9 ++++-----
 2 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/cmd/tsconnect/build-pkg.go b/cmd/tsconnect/build-pkg.go
index e0220b42f..8b0b6a79b 100644
--- a/cmd/tsconnect/build-pkg.go
+++ b/cmd/tsconnect/build-pkg.go
@@ -12,6 +12,7 @@ import (
 	"path"
 
 	"github.com/tailscale/hujson"
+	"tailscale.com/util/precompress"
 	"tailscale.com/version"
 )
 
@@ -37,6 +38,10 @@ func runBuildPkg() {
 
 	runEsbuild(*buildOptions)
 
+	if err := precompressWasm(); err != nil {
+		log.Fatalf("Could not pre-recompress wasm: %v", err)
+	}
+
 	log.Printf("Generating types...\n")
 	if err := runYarn("pkg-types"); err != nil {
 		log.Fatalf("Type generation failed: %v", err)
@@ -49,6 +54,13 @@ func runBuildPkg() {
 	log.Printf("Built package version %s", version.Long)
 }
 
+func precompressWasm() error {
+	log.Printf("Pre-compressing main.wasm...\n")
+	return precompress.Precompress(path.Join(*pkgDir, "main.wasm"), precompress.Options{
+		FastCompression: *fastCompression,
+	})
+}
+
 func updateVersion() error {
 	packageJSONBytes, err := os.ReadFile("package.json.tmpl")
 	if err != nil {
diff --git a/util/precompress/precompress.go b/util/precompress/precompress.go
index e5caeca13..32181dffa 100644
--- a/util/precompress/precompress.go
+++ b/util/precompress/precompress.go
@@ -42,7 +42,7 @@ func PrecompressDir(dirPath string, options Options) error {
 		}
 
 		eg.Go(func() error {
-			return precompress(p, options)
+			return Precompress(p, options)
 		})
 		return nil
 	})
@@ -81,12 +81,11 @@ func OpenPrecompressedFile(w http.ResponseWriter, r *http.Request, path string,
 }
 
 var compressibleExtensions = map[string]bool{
-	".js":   true,
-	".css":  true,
-	".wasm": true,
+	".js":  true,
+	".css": true,
 }
 
-func precompress(path string, options Options) error {
+func Precompress(path string, options Options) error {
 	contents, err := os.ReadFile(path)
 	if err != nil {
 		return err