support loading a raw private key from the environment. (#54)

* support loading a raw private key from the environment.
Also made integration test a new target to simplify local unit testing

* fail if both private key and key path are provided.
added a comment to clarify how the private key should be encoded

Author: kommendorkapten

.github/workflows/build.yml

@@ -45,4 +45,4 @@ jobs:
         run: go install sigs.k8s.io/controller-runtime/tools/setup-envtest@4dbfa5c66aa24a35003c41507385c2a91e94d404 # release-0.23
       - name: Test
         run: |
-          make test
+          make integration-test

Makefile

@@ -19,7 +19,10 @@ fmt:
 	go fmt ./...
 
 test:
-	KUBEBUILDER_ASSETS=$$(setup-envtest use -p path) go test ./...
+	go test ./...
+
+integration-test:
+	KUBEBUILDER_ASSETS=$$(setup-envtest use -p path) go test -tags integration_test ./...
 
 test-short:
 	go test -short ./...

cmd/deployment-tracker/main.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"context"
+	"encoding/base64"
 	"flag"
 	"fmt"
 	"log"
@@ -67,6 +68,16 @@ func main() {
 	opts := slog.HandlerOptions{Level: slog.LevelInfo}
 	slog.SetDefault(slog.New(slog.NewJSONHandler(os.Stdout, &opts)))
 
+	var ghAppPrivateKey []byte
+	if b64Key := os.Getenv("GH_APP_PRIVATE_KEY"); b64Key != "" {
+		var err error
+		ghAppPrivateKey, err = base64.StdEncoding.DecodeString(b64Key)
+		if err != nil {
+			slog.Error("Failed to base64 decode GH_APP_PRIVATE_KEY", "error", err)
+			os.Exit(1)
+		}
+	}
+
 	var cntrlCfg = controller.Config{
 		Template:            getEnvOrDefault("DN_TEMPLATE", defaultTemplate),
 		LogicalEnvironment:  os.Getenv("LOGICAL_ENVIRONMENT"),
@@ -76,10 +87,16 @@ func main() {
 		BaseURL:             getEnvOrDefault("BASE_URL", "api.github.com"),
 		GHAppID:             getEnvOrDefault("GH_APP_ID", ""),
 		GHInstallID:         getEnvOrDefault("GH_INSTALL_ID", ""),
-		GHAppPrivateKey:     getEnvOrDefault("GH_APP_PRIV_KEY", ""),
+		GHAppPrivateKey:     ghAppPrivateKey,
+		GHAppPrivateKeyPath: getEnvOrDefault("GH_APP_PRIV_KEY_PATH", ""),
 		Organization:        os.Getenv("GITHUB_ORG"),
 	}
 
+	if len(cntrlCfg.GHAppPrivateKey) > 0 && cntrlCfg.GHAppPrivateKeyPath != "" {
+		slog.Error("Both GH_APP_PRIVATE_KEY and GH_APP_PRIV_KEY_PATH are set. Only one can be used.")
+		os.Exit(1)
+	}
+
 	if !controller.ValidTemplate(cntrlCfg.Template) {
 		slog.Error("Template must contain at least one placeholder",
 			"template", cntrlCfg.Template,

internal/controller/config.go

@@ -20,12 +20,15 @@ type Config struct {
 	PhysicalEnvironment string
 	Cluster             string
 	//nolint:gosec
-	APIToken        string
-	BaseURL         string
-	GHAppID         string
-	GHInstallID     string
-	GHAppPrivateKey string
-	Organization    string
+	APIToken    string
+	BaseURL     string
+	GHAppID     string
+	GHInstallID string
+	// GHAppPrivateKey must be the PEM Encoding of the
+	// private key
+	GHAppPrivateKey     []byte
+	GHAppPrivateKeyPath string
+	Organization        string
 }
 
 // ValidTemplate verifies that at least one placeholder is present

internal/controller/controller.go

@@ -87,8 +87,13 @@ func New(clientset kubernetes.Interface, metadataAggregator podMetadataAggregato
 	}
 	if cfg.GHAppID != "" &&
 		cfg.GHInstallID != "" &&
-		cfg.GHAppPrivateKey != "" {
-		clientOpts = append(clientOpts, deploymentrecord.WithGHApp(cfg.GHAppID, cfg.GHInstallID, cfg.GHAppPrivateKey))
+		(len(cfg.GHAppPrivateKey) > 0 || cfg.GHAppPrivateKeyPath != "") {
+		clientOpts = append(clientOpts, deploymentrecord.WithGHApp(
+			cfg.GHAppID,
+			cfg.GHInstallID,
+			cfg.GHAppPrivateKey,
+			cfg.GHAppPrivateKeyPath,
+		))
 	}
 
 	apiClient, err := deploymentrecord.NewClient(

internal/controller/controller_integration_test.go

@@ -1,3 +1,5 @@
+//go:build integration_test
+
 package controller
 
 import (

pkg/deploymentrecord/client.go

@@ -105,8 +105,12 @@ func WithAPIToken(token string) ClientOption {
 // WithGHApp configures a GitHub app to use for authentication.
 // If provided values are invalid, this will panic.
 // If an API token is also set, the GitHub App will take precedence.
-func WithGHApp(id, installID, pk string) ClientOption {
+func WithGHApp(id, installID string, pkBytes []byte, pkPath string) ClientOption {
 	return func(c *Client) {
+		if len(pkBytes) > 0 && pkPath != "" {
+			panic("both GitHub App private key and private key path are set")
+		}
+
 		pid, err := strconv.Atoi(id)
 		if err != nil {
 			panic(err)
@@ -115,11 +119,21 @@ func WithGHApp(id, installID, pk string) ClientOption {
 		if err != nil {
 			panic(err)
 		}
-		c.transport, err = ghinstallation.NewKeyFromFile(
-			http.DefaultTransport,
-			int64(pid),
-			int64(piid),
-			pk)
+
+		if len(pkBytes) > 0 {
+			c.transport, err = ghinstallation.New(
+				http.DefaultTransport,
+				int64(pid),
+				int64(piid),
+				pkBytes)
+		} else {
+			c.transport, err = ghinstallation.NewKeyFromFile(
+				http.DefaultTransport,
+				int64(pid),
+				int64(piid),
+				pkPath)
+		}
+
 		if err != nil {
 			panic(err)
 		}