fix: PHP - Add composer autoload when a cached vendor folder is used as the autoload files include a list of classes outside of the vendor folder

Author: rlweb

pkg/php/php.go

@@ -147,7 +147,16 @@ func composerInstall(ctx *gcp.Context, flags []string) error {
 	return nil
 }
 
-// ComposerInstall runs `composer install`, using the cache iff a lock file is present.
+// composerDumpAutoload runs `composer dump-autoload` with the given flags.
+func composerDumpAutoload(ctx *gcp.Context, flags []string) error {
+	cmd := append([]string{"composer", "dump-autoload"}, flags...)
+	if _, err := ctx.Exec(cmd, gcp.WithUserAttribution); err != nil {
+		return err
+	}
+	return nil
+}
+
+// ComposerInstall runs `composer install`, using the cache if a lock file is present.
 // It creates a layer, so it returns the layer so that the caller may further modify it
 // if they desire.
 func ComposerInstall(ctx *gcp.Context, cacheTag string) (*libcnb.Layer, error) {
@@ -201,6 +210,12 @@ func ComposerInstall(ctx *gcp.Context, cacheTag string) (*libcnb.Layer, error) {
 		if _, err := ctx.Exec([]string{"cp", "--archive", layerVendor, Vendor}, gcp.WithUserTimingAttribution); err != nil {
 			return nil, err
 		}
+		// Why re-generate the autoload files? Since these autoload files include list of all PSR auto-loaded files (including local workspace files)
+		// This will cause issues for files added/removed since the last cache as these won't be within the classmap
+		ctx.Logf("Re-generating autoload files.")
+		if err := composerDumpAutoload(ctx, []string{"--optimize"}); err != nil {
+			return nil, err
+		}
 	} else {
 		ctx.Logf("Installing application dependencies.")
 		// Clear layer so we don't end up with outdated dependencies (e.g. something was removed from composer.json).