bib: rename --config to --iso-config

Rename the --config option to --iso-config and error if it is
used for anything other than the ISO image.

bib/cmd/bootc-image-builder/main.go

@@ -235,7 +235,7 @@ func manifestFromCobra(cmd *cobra.Command, args []string) ([]byte, error) {
 	}
 
 	imgref := args[0]
-	configFile, _ := cmd.Flags().GetString("config")
+	isoConfigFile, _ := cmd.Flags().GetString("iso-config")
 	imgTypes, _ := cmd.Flags().GetStringArray("type")
 	rpmCacheRoot, _ := cmd.Flags().GetString("rpmmd")
 	targetArch, _ := cmd.Flags().GetString("target-arch")
@@ -262,11 +262,16 @@ func manifestFromCobra(cmd *cobra.Command, args []string) ([]byte, error) {
 		return nil, err
 	}
 
+	// bootc does not yet support arbitray blueprint customizations
+	if buildType != BuildTypeISO && isoConfigFile != "" {
+		return nil, fmt.Errorf("the --iso-config switch is only supported for ISO images")
+	}
+
 	var config *BuildConfig
-	if configFile != "" {
-		config, err = loadConfig(configFile)
+	if isoConfigFile != "" {
+		config, err = loadConfig(isoConfigFile)
 		if err != nil {
-			return nil, err
+			return nil, fmt.Errorf("cannot load config: %w", err)
 		}
 	} else {
 		config = &BuildConfig{}
@@ -351,7 +356,7 @@ func cmdBuild(cmd *cobra.Command, args []string) error {
 	fmt.Printf("Generating manifest %s\n", manifest_fname)
 	mf, err := manifestFromCobra(cmd, args)
 	if err != nil {
-		panic(err)
+		return err
 	}
 	fmt.Print("DONE\n")
 
@@ -468,7 +473,7 @@ func run() error {
 	}
 	rootCmd.AddCommand(manifestCmd)
 	manifestCmd.Flags().Bool("tls-verify", true, "require HTTPS and verify certificates when contacting registries")
-	manifestCmd.Flags().String("config", "", "build config file")
+	manifestCmd.Flags().String("iso-config", "", "build config file for the iso")
 	manifestCmd.Flags().String("rpmmd", "/rpmmd", "rpm metadata cache directory")
 	manifestCmd.Flags().String("target-arch", "", "build for the given target architecture (experimental)")
 	manifestCmd.Flags().StringArray("type", []string{"qcow2"}, fmt.Sprintf("image types to build [%s]", allImageTypesString()))
@@ -492,7 +497,7 @@ func run() error {
 			return err
 		}
 	}
-	if err := buildCmd.MarkFlagFilename("config"); err != nil {
+	if err := buildCmd.MarkFlagFilename("iso-config"); err != nil {
 		return err
 	}
 	buildCmd.MarkFlagsRequiredTogether("aws-region", "aws-bucket", "aws-ami-name")

test/test_opts.py

@@ -1,4 +1,5 @@
 import subprocess
+import sys
 
 import pytest
 
@@ -27,3 +28,41 @@ def test_bib_chown_opts(tmp_path, build_fake_container, chown_opt, expected_uid_
         assert p.exists()
         assert p.stat().st_uid == expected_uid_gid[0]
         assert p.stat().st_gid == expected_uid_gid[1]
+
+
+def test_bib_config_errors_for_default(tmp_path, build_fake_container):
+    output_path = tmp_path / "output"
+    output_path.mkdir(exist_ok=True)
+
+    ret = subprocess.run([
+        "podman", "run", "--rm",
+        "--privileged",
+        "--security-opt", "label=type:unconfined_t",
+        "-v", f"{output_path}:/output",
+        build_fake_container,
+        "--iso-config", "/some/random/config",
+        "quay.io/centos-bootc/centos-bootc:stream9",
+    ], check=False, encoding="utf8", stdout=sys.stdout, stderr=subprocess.PIPE)
+    assert ret.returncode != 0
+    assert "the --iso-config switch is only supported for ISO images" in ret.stderr
+
+
+def test_bib_iso_config_is_parsed(tmp_path, build_fake_container):
+    output_path = tmp_path / "output"
+    output_path.mkdir(exist_ok=True)
+
+    # check that config.json is tried to be loaded
+    (tmp_path / "config.json").write_text("invalid-json", encoding="utf8")
+    ret = subprocess.run([
+        "podman", "run", "--rm",
+        "--privileged",
+        "--security-opt", "label=type:unconfined_t",
+        "-v", f"{output_path}:/output",
+        "-v", f"{tmp_path}/config.json:/config.json",
+        build_fake_container,
+        "--iso-config", "/config.json",
+        "--type", "anaconda-iso",
+        "quay.io/centos-bootc/centos-bootc:stream9",
+    ], check=False, encoding="utf8", stdout=sys.stdout, stderr=subprocess.PIPE)
+    assert ret.returncode != 0
+    assert "cannot load config: invalid character" in ret.stderr