T3965: arm: build script: inheritence in flavor_configs and bootloader options

data/defaults.json

@@ -8,6 +8,7 @@
   "kernel_version": "5.10.76",
   "kernel_flavor": "amd64-vyos",
   "release_train": "sagitta",
+  "bootloaders": "syslinux,grub-efi",
   "additional_repositories": [
     "deb [arch=amd64] https://repo.saltproject.io/py3/debian/10/amd64/3003 buster main",
     "deb [arch=amd64] http://repo.powerdns.com/debian bullseye-rec-45 main"

data/generic-arm64.json

@@ -0,0 +1,6 @@
+{
+  "inherit_from": "data/defaults.json",
+  "architecture": "arm64",
+  "kernel_flavor": "v8-arm64-vyos",
+  "bootloaders": "grub-efi"
+}

scripts/build-config

@@ -48,14 +48,27 @@ def get_validator(optdict, name):
     except KeyError:
         return None
 
+def load_config(filename):
+    with open(filename, 'r') as f:
+        print(f'Loading {filename}')
+        this_config = json.load(f)
+
+    if not 'inherit_from' in this_config:
+      print(f'No inheritance detected')
+      return this_config
+
+    inherited_config = load_config(this_config['inherit_from'])
+    del this_config['inherit_from']
+    inherited_config.update(this_config)
+    return inherited_config
+
 
 # Load the build flavor file
 build_flavor = os.getenv('VYOS_BUILD_FLAVOR')
 if build_flavor is None:
     build_flavor = defaults.DEFAULT_BUILD_FLAVOR
 try:
-    with open(build_flavor, 'r') as f:
-        build_defaults = json.load(f)
+    build_defaults = load_config(build_flavor)
 except Exception as e:
     print("Failed to open the build flavor file {0}: {1}".format(build_flavor, e))
     sys.exit(1)
@@ -143,6 +156,7 @@ if env_check_retval > 0:
 
 args['kernel_version'] = build_defaults['kernel_version']
 args['kernel_flavor'] = build_defaults['kernel_flavor']
+args['bootloaders'] = build_defaults['bootloaders']
 
 
 # Save to file

scripts/live-build-config

@@ -39,7 +39,7 @@ lb config noauto \
         --bootappend-live-failsafe "live components memtest noapic noapm nodma nomce nolapic nomodeset nosmp nosplash vga=normal console=ttyS0,115200 console=tty0 net.ifnames=0 biosdevname=0" \
         --linux-flavours {{kernel_flavor}} \
         --linux-packages linux-image-{{kernel_version}} \
-        --bootloader syslinux,grub-efi \
+        --bootloader {{bootloaders}} \
         --binary-images iso-hybrid \
         --checksums 'sha256 md5' \
         --debian-installer none \