launch: include validation warnings in returned message

In case some warnings are issued when launching a workflow, the `launch`
endpoint will now include them in a new `validation_warnings` key.

Closes reanahub/reana-client#660.

CHANGES.rst

@@ -4,6 +4,7 @@ Changes
 Version 0.9.1 (UNRELEASED)
 --------------------------
 
+- Changes OpenAPI specification to include the optional ``validation_warnings`` key in the response of the ``launch`` endpoint.
 - Changes OpenAPI specification with respect to return the maximum inactivity time before automatic closure of interactive sessions in ``info`` endpoint.
 - Adds the timestamp of when the workflow was stopped (``run_stopped_at``) to the workflow list and the workflow status endpoints.
 - Adds the content of the ``REANA_GITLAB_HOST`` environment variable to the list of GitLab instances from which it is possible to launch a workflow.

docs/openapi.json

@@ -582,13 +582,22 @@
                 "message": {
                   "type": "string"
                 },
+                "validation_warnings": {
+                  "description": "Dictionary of validation warnings, if any. Each key is a property that was not correctly validated.",
+                  "type": "object"
+                },
                 "workflow_id": {
                   "type": "string"
                 },
                 "workflow_name": {
                   "type": "string"
                 }
               },
+              "required": [
+                "workflow_id",
+                "workflow_name",
+                "message"
+              ],
               "type": "object"
             }
           },

reana_server/rest/launch.py

@@ -104,13 +104,22 @@ def launch(user, url, name="", parameters="{}", specification=None):
             Request succeeded. Information of the workflow launched.
           schema:
             type: object
+            required:
+              - workflow_id
+              - workflow_name
+              - message
             properties:
               workflow_id:
                 type: string
               workflow_name:
                 type: string
               message:
                 type: string
+              validation_warnings:
+                description: >-
+                    Dictionary of validation warnings, if any. Each
+                    key is a property that was not correctly validated.
+                type: object
           examples:
             application/json:
               {
@@ -180,7 +189,7 @@ def launch(user, url, name="", parameters="{}", specification=None):
         with load_reana_spec_lock:
             reana_yaml = load_reana_spec(spec_path, workspace_path=tmpdir)
         input_parameters = json.loads(parameters)
-        validate_workflow(reana_yaml, input_parameters)
+        validation_warnings = validate_workflow(reana_yaml, input_parameters)
 
         # Keep only files and directories listed as workflow's inputs
         filter_input_files(tmpdir, reana_yaml)
@@ -223,6 +232,8 @@ def launch(user, url, name="", parameters="{}", specification=None):
             "workflow_name": workflow.name,
             "message": "The workflow has been successfully submitted.",
         }
+        if validation_warnings:
+            response_data["validation_warnings"] = validation_warnings
         return LaunchSchema().dump(response_data)
     except HTTPError as e:
         logging.error(traceback.format_exc())
@@ -271,3 +282,4 @@ class LaunchSchema(Schema):
     workflow_id = fields.UUID()
     workflow_name = fields.Str()
     message = fields.Str()
+    validation_warnings = fields.Dict()

reana_server/validation.py

@@ -10,7 +10,7 @@
 
 import itertools
 import pathlib
-from typing import Dict
+from typing import Dict, List
 
 from reana_commons.config import WORKSPACE_PATHS
 from reana_commons.errors import REANAValidationError
@@ -107,7 +107,7 @@ def validate_inputs(reana_yaml: Dict) -> None:
             )
 
 
-def validate_workflow(reana_yaml: Dict, input_parameters: Dict) -> None:
+def validate_workflow(reana_yaml: Dict, input_parameters: Dict) -> List[Exception]:
     """Validate REANA workflow specification by calling all the validation utilities.
 
     :param reana_yaml: dictionary which represents REANA specification file.
@@ -119,12 +119,13 @@ def validate_workflow(reana_yaml: Dict, input_parameters: Dict) -> None:
     operational_options = reana_yaml.get("inputs", {}).get("options", {})
     original_parameters = reana_yaml.get("inputs", {}).get("parameters", {})
 
-    validate_reana_yaml(reana_yaml)
+    reana_yaml_warnings = validate_reana_yaml(reana_yaml)
     validate_operational_options(workflow_type, operational_options)
     validate_input_parameters(input_parameters, original_parameters)
     validate_compute_backends(reana_yaml)
     validate_workspace_path(reana_yaml)
     validate_inputs(reana_yaml)
+    return reana_yaml_warnings
 
 
 def validate_retention_rule(rule: str, days: int) -> None: