Support for py2-py3 migration scripts (#334)

Added following commands:
1. calm decompile app-migratable-bp <app_name> : Will decompile bp that
will only contain escript tasks
2. calm describe app-migratable-entities <app_name> : Will describe
escript tasks that can be modified under diff entities.
3. calm update app-migratable-bp <app_name> -f <bp_file>: Will update
the app-blueprint escripts

---------

Signed-off-by: Satheesh Rajendran <[email protected]>
Co-authored-by: Gullapalli Akhil Sai <[email protected]>
Co-authored-by: Satheesh Rajendran <[email protected]>
(cherry picked from commit c8ad0e626cc643c3c3acc8be66d9609ebf6ce30c)

calm/dsl/api/application.py

@@ -11,6 +11,10 @@ def __init__(self, connection):
         self.DOWNLOAD_RUNLOG = self.ITEM + "/app_runlogs/{}/output/download"
         self.ACTION_VARIABLE = self.ITEM + "/actions/{}/variables"
         self.RECOVERY_GROUPS_LIST = self.ITEM + "/recovery_groups/list"
+        self.BLUEPRINTS_ORIGINAL = self.ITEM + "/blueprints/original"
+        self.BLUEPRINT_ENTITIES_ESCRIPT_UPDATE = (
+            self.ITEM + "/blueprints/entities/update"
+        )
 
     def run_action(self, app_id, action_id, payload):
         return self.connection._call(
@@ -20,6 +24,21 @@ def run_action(self, app_id, action_id, payload):
             method=REQUEST.METHOD.POST,
         )
 
+    def blueprints_original(self, app_id):
+        return self.connection._call(
+            self.BLUEPRINTS_ORIGINAL.format(app_id),
+            verify=False,
+            method=REQUEST.METHOD.GET,
+        )
+
+    def blueprints_entities_update(self, app_id, payload):
+        return self.connection._call(
+            self.BLUEPRINT_ENTITIES_ESCRIPT_UPDATE.format(app_id),
+            request_json=payload,
+            verify=False,
+            method=REQUEST.METHOD.PUT,
+        )
+
     def run_patch(self, app_id, patch_id, payload):
         return self.connection._call(
             self.PATCH_RUN.format(app_id, patch_id),

calm/dsl/builtins/models/package.py

@@ -147,7 +147,7 @@ def decompile(mcls, cdict, context=[], prefix=""):
         elif package_type == "SUBSTRATE_IMAGE":
             disk_pkg_data = {
                 "name": cdict["name"],
-                "description": cdict["description"],
+                "description": cdict.get("description", ""),
                 "options": cdict["options"],
             }
             types = EntityTypeBase.get_entity_types()

calm/dsl/cli/app_commands.py

@@ -2,7 +2,18 @@
 
 from calm.dsl.api import get_api_client
 
-from .main import main, get, describe, delete, run, watch, download, create, update
+from .main import (
+    main,
+    get,
+    describe,
+    delete,
+    run,
+    watch,
+    download,
+    create,
+    update,
+    decompile,
+)
 from .utils import Display, FeatureFlagGroup
 from .apps import (
     get_apps,
@@ -14,6 +25,9 @@
     delete_app,
     download_runlog,
     create_app,
+    describe_app_actions_to_update,
+    decompile_app_migratable_bp,
+    update_app_migratable_bp,
 )
 from calm.dsl.log import get_logging_handle
 
@@ -104,6 +118,44 @@ def _get_apps(name, filter_by, limit, offset, quiet, all_items, out):
     get_apps(name, filter_by, limit, offset, quiet, all_items, out)
 
 
+@describe.command("app-migratable-entities")
+@click.argument("app_name")
+def _describe_app(app_name):
+    """Display app-actions to be migrated"""
+
+    describe_app_actions_to_update(app_name)
+
+
+@decompile.command("app-migratable-bp")
+@click.option(
+    "--dir",
+    "-d",
+    "bp_dir",
+    default=None,
+    help="Blueprint directory location used for placing decompiled entities",
+)
+@click.argument("app_name")
+def _decompile_app_migratable_bp(app_name, bp_dir):
+    """Decompile app-blueprint app-actions to be migrated"""
+
+    decompile_app_migratable_bp(app_name, bp_dir)
+
+
+@update.command("app-migratable-bp")
+@click.option(
+    "--file",
+    "-f",
+    "bp_file",
+    type=click.Path(exists=True, file_okay=True, dir_okay=False, readable=True),
+    help="Path to Blueprint file",
+)
+@click.argument("app_name")
+def _update_app_migratable_bp(app_name, bp_file):
+    """update app-blueprint app-actions to be migrated"""
+
+    update_app_migratable_bp(app_name, bp_file)
+
+
 @describe.command("app")
 @click.argument("app_name")
 @click.option(