godev: create config struct and document local development process
Change-Id: I370490ec93934be34d9df29b6f3819fca4a93ed6
Reviewed-on: https://go-review.googlesource.com/c/telemetry/+/499916
Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>
Reviewed-by: Peter Weinberger <pjw@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Jamal Carvalho <jamal@golang.org>
diff --git a/godev/cmd/telemetrygodev/README.md b/godev/cmd/telemetrygodev/README.md
index 78dad44..b792bac 100644
--- a/godev/cmd/telemetrygodev/README.md
+++ b/godev/cmd/telemetrygodev/README.md
@@ -4,7 +4,21 @@
For local development, simply build and run. It serves on localhost:8080.
- go run .
+ go run ./cmd/telemetrygodev
+
+By default, the server will use the filesystem for storage object I/O. Run the
+cloud storage emulator and use the -gcs flag to use the Cloud Storage API.
+
+ ./devtools/localstorage.sh
+ go run ./cmd/telemetrygodev --gcs
+
+### Environment Variables
+
+| Name | Default | Description |
+| ---------------------------------- | -------------- | --------------------------------------------------------- |
+| GO_TELEMETRY_PROJECT_ID | go-telemetry | GCP project ID |
+| GO_TELEMETRY_STORAGE_EMULATOR_HOST | localhost:8081 | Host for the Cloud Storage emulator |
+| GO_TELEMETRY_LOCAL_STORAGE | .localstorage | Directory for storage emulator I/O or file system storage |
## Testing
diff --git a/godev/cmd/telemetrygodev/config.go b/godev/cmd/telemetrygodev/config.go
new file mode 100644
index 0000000..b92929c
--- /dev/null
+++ b/godev/cmd/telemetrygodev/config.go
@@ -0,0 +1,63 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "flag"
+ "os"
+)
+
+type config struct {
+ // Port is the port your HTTP server should listen on.
+ Port string
+
+ // ProjectID is a GCP project ID.
+ ProjectID string
+
+ // StorageEmulatorHost is a network address for a Cloud Storage emulator.
+ StorageEmulatorHost string
+
+ // LocalStorage is a directory for storage I/O used when the using the filesystem
+ // or storage emulator modes.
+ LocalStorage string
+
+ // UploadBucket is the storage bucket for report uploads.
+ UploadBucket string
+
+ // UseGCS is true if the server should use the Cloud Storage API for reading and
+ // writing storage objects.
+ UseGCS bool
+
+ // DevMode is true if the server should read content files from the filesystem.
+ // If false, content files are read from the embed.FS in ../content.go.
+ DevMode bool
+}
+
+var (
+ devMode = flag.Bool("dev", false, "load static content and templates from the filesystem")
+ useGCS = flag.Bool("gcs", false, "use Cloud Storage for reading and writing storage objects")
+)
+
+// newConfig returns a new config. Getting the config should follow a call to flag.Parse.
+func newConfig() *config {
+ // K_SERVICE is a Cloud Run environment variable.
+ service := env("K_SERVICE", "local-telemetry")
+ return &config{
+ Port: env("PORT", "8080"),
+ ProjectID: env("GO_TELEMETRY_PROJECT_ID", "go-telemetry"),
+ StorageEmulatorHost: env("GO_TELEMETRY_STORAGE_EMULATOR_HOST", "localhost:8081"),
+ LocalStorage: env("GO_TELEMETRY_LOCAL_STORAGE", ".localstorage"),
+ UploadBucket: service + "-uploads",
+ UseGCS: *useGCS,
+ DevMode: *devMode,
+ }
+}
+
+func env(key, fallback string) string {
+ if value, ok := os.LookupEnv(key); ok {
+ return value
+ }
+ return fallback
+}
diff --git a/godev/cmd/telemetrygodev/config_test.go b/godev/cmd/telemetrygodev/config_test.go
new file mode 100644
index 0000000..b26c7b7
--- /dev/null
+++ b/godev/cmd/telemetrygodev/config_test.go
@@ -0,0 +1,23 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "reflect"
+ "testing"
+)
+
+func TestConfig(t *testing.T) {
+ want := &config{
+ Port: "8080",
+ ProjectID: "go-telemetry",
+ StorageEmulatorHost: "localhost:8081",
+ LocalStorage: ".localstorage",
+ UploadBucket: "local-telemetry-uploads",
+ }
+ if got := newConfig(); !reflect.DeepEqual(got, want) {
+ t.Errorf("Config() = %v, want %v", got, want)
+ }
+}
diff --git a/godev/cmd/telemetrygodev/main.go b/godev/cmd/telemetrygodev/main.go
index 684dfbf..7afad18 100644
--- a/godev/cmd/telemetrygodev/main.go
+++ b/godev/cmd/telemetrygodev/main.go
@@ -19,17 +19,13 @@
"golang.org/x/telemetry/godev/internal/unionfs"
)
-var (
- addr = flag.String("addr", ":8080", "server listens on the given TCP network address")
- dev = flag.Bool("dev", false, "load static content and templates from the filesystem")
-)
-
func main() {
flag.Parse()
- s := content.Server(fsys(*dev))
+ cfg := newConfig()
+ s := content.Server(fsys(cfg.DevMode))
mw := middleware.Default
- fmt.Printf("server listening at http://%s\n", *addr)
- log.Fatal(http.ListenAndServe(*addr, mw(s)))
+ fmt.Printf("server listening at http://localhost:%s\n", cfg.Port)
+ log.Fatal(http.ListenAndServe(":"+cfg.Port, mw(s)))
}
func fsys(fromOS bool) fs.FS {
diff --git a/godev/devtools/localstorage.sh b/godev/devtools/localstorage.sh
index fb21cc1..376faf8 100755
--- a/godev/devtools/localstorage.sh
+++ b/godev/devtools/localstorage.sh
@@ -32,7 +32,7 @@
version=v0.0.0-20230523204811-eccb7d2267b0
port=8081
-dir=.localstorage
+dir="${GO_TELEMETRY_LOCAL_STORAGE:-.localstorage}"
if [ ! -z "$1" ]; then
dir="$1"
fi
