feat(workflow): workflow as tool output schema (#26241)

Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
Co-authored-by: crazywoola <100913391+crazywoola@users.noreply.github.com>
Co-authored-by: Novice <novice12185727@gmail.com>

api/tests/unit_tests/core/tools/workflow_as_tool/test_tool.py

@@ -3,7 +3,7 @@ import pytest
 from core.app.entities.app_invoke_entities import InvokeFrom
 from core.tools.__base.tool_runtime import ToolRuntime
 from core.tools.entities.common_entities import I18nObject
-from core.tools.entities.tool_entities import ToolEntity, ToolIdentity
+from core.tools.entities.tool_entities import ToolEntity, ToolIdentity, ToolInvokeMessage
 from core.tools.errors import ToolInvokeError
 from core.tools.workflow_as_tool.tool import WorkflowTool
 
@@ -51,3 +51,166 @@ def test_workflow_tool_should_raise_tool_invoke_error_when_result_has_error_fiel
         # actually `run` the tool.
         list(tool.invoke("test_user", {}))
     assert exc_info.value.args == ("oops",)
+
+
+def test_workflow_tool_should_generate_variable_messages_for_outputs(monkeypatch: pytest.MonkeyPatch):
+    """Test that WorkflowTool should generate variable messages when there are outputs"""
+    entity = ToolEntity(
+        identity=ToolIdentity(author="test", name="test tool", label=I18nObject(en_US="test tool"), provider="test"),
+        parameters=[],
+        description=None,
+        has_runtime_parameters=False,
+    )
+    runtime = ToolRuntime(tenant_id="test_tool", invoke_from=InvokeFrom.EXPLORE)
+    tool = WorkflowTool(
+        workflow_app_id="",
+        workflow_as_tool_id="",
+        version="1",
+        workflow_entities={},
+        workflow_call_depth=1,
+        entity=entity,
+        runtime=runtime,
+    )
+
+    # Mock workflow outputs
+    mock_outputs = {"result": "success", "count": 42, "data": {"key": "value"}}
+
+    # needs to patch those methods to avoid database access.
+    monkeypatch.setattr(tool, "_get_app", lambda *args, **kwargs: None)
+    monkeypatch.setattr(tool, "_get_workflow", lambda *args, **kwargs: None)
+
+    # Mock user resolution to avoid database access
+    from unittest.mock import Mock
+
+    mock_user = Mock()
+    monkeypatch.setattr(tool, "_resolve_user", lambda *args, **kwargs: mock_user)
+
+    # replace `WorkflowAppGenerator.generate` 's return value.
+    monkeypatch.setattr(
+        "core.app.apps.workflow.app_generator.WorkflowAppGenerator.generate",
+        lambda *args, **kwargs: {"data": {"outputs": mock_outputs}},
+    )
+    monkeypatch.setattr("libs.login.current_user", lambda *args, **kwargs: None)
+
+    # Execute tool invocation
+    messages = list(tool.invoke("test_user", {}))
+
+    # Verify generated messages
+    # Should contain: 3 variable messages + 1 text message + 1 JSON message = 5 messages
+    assert len(messages) == 5
+
+    # Verify variable messages
+    variable_messages = [msg for msg in messages if msg.type == ToolInvokeMessage.MessageType.VARIABLE]
+    assert len(variable_messages) == 3
+
+    # Verify content of each variable message
+    variable_dict = {msg.message.variable_name: msg.message.variable_value for msg in variable_messages}
+    assert variable_dict["result"] == "success"
+    assert variable_dict["count"] == 42
+    assert variable_dict["data"] == {"key": "value"}
+
+    # Verify text message
+    text_messages = [msg for msg in messages if msg.type == ToolInvokeMessage.MessageType.TEXT]
+    assert len(text_messages) == 1
+    assert '{"result": "success", "count": 42, "data": {"key": "value"}}' in text_messages[0].message.text
+
+    # Verify JSON message
+    json_messages = [msg for msg in messages if msg.type == ToolInvokeMessage.MessageType.JSON]
+    assert len(json_messages) == 1
+    assert json_messages[0].message.json_object == mock_outputs
+
+
+def test_workflow_tool_should_handle_empty_outputs(monkeypatch: pytest.MonkeyPatch):
+    """Test that WorkflowTool should handle empty outputs correctly"""
+    entity = ToolEntity(
+        identity=ToolIdentity(author="test", name="test tool", label=I18nObject(en_US="test tool"), provider="test"),
+        parameters=[],
+        description=None,
+        has_runtime_parameters=False,
+    )
+    runtime = ToolRuntime(tenant_id="test_tool", invoke_from=InvokeFrom.EXPLORE)
+    tool = WorkflowTool(
+        workflow_app_id="",
+        workflow_as_tool_id="",
+        version="1",
+        workflow_entities={},
+        workflow_call_depth=1,
+        entity=entity,
+        runtime=runtime,
+    )
+
+    # needs to patch those methods to avoid database access.
+    monkeypatch.setattr(tool, "_get_app", lambda *args, **kwargs: None)
+    monkeypatch.setattr(tool, "_get_workflow", lambda *args, **kwargs: None)
+
+    # Mock user resolution to avoid database access
+    from unittest.mock import Mock
+
+    mock_user = Mock()
+    monkeypatch.setattr(tool, "_resolve_user", lambda *args, **kwargs: mock_user)
+
+    # replace `WorkflowAppGenerator.generate` 's return value.
+    monkeypatch.setattr(
+        "core.app.apps.workflow.app_generator.WorkflowAppGenerator.generate",
+        lambda *args, **kwargs: {"data": {}},
+    )
+    monkeypatch.setattr("libs.login.current_user", lambda *args, **kwargs: None)
+
+    # Execute tool invocation
+    messages = list(tool.invoke("test_user", {}))
+
+    # Verify generated messages
+    # Should contain: 0 variable messages + 1 text message + 1 JSON message = 2 messages
+    assert len(messages) == 2
+
+    # Verify no variable messages
+    variable_messages = [msg for msg in messages if msg.type == ToolInvokeMessage.MessageType.VARIABLE]
+    assert len(variable_messages) == 0
+
+    # Verify text message
+    text_messages = [msg for msg in messages if msg.type == ToolInvokeMessage.MessageType.TEXT]
+    assert len(text_messages) == 1
+    assert text_messages[0].message.text == "{}"
+
+    # Verify JSON message
+    json_messages = [msg for msg in messages if msg.type == ToolInvokeMessage.MessageType.JSON]
+    assert len(json_messages) == 1
+    assert json_messages[0].message.json_object == {}
+
+
+def test_create_variable_message():
+    """Test the functionality of creating variable messages"""
+    entity = ToolEntity(
+        identity=ToolIdentity(author="test", name="test tool", label=I18nObject(en_US="test tool"), provider="test"),
+        parameters=[],
+        description=None,
+        has_runtime_parameters=False,
+    )
+    runtime = ToolRuntime(tenant_id="test_tool", invoke_from=InvokeFrom.EXPLORE)
+    tool = WorkflowTool(
+        workflow_app_id="",
+        workflow_as_tool_id="",
+        version="1",
+        workflow_entities={},
+        workflow_call_depth=1,
+        entity=entity,
+        runtime=runtime,
+    )
+
+    # Test different types of variable values
+    test_cases = [
+        ("string_var", "test string"),
+        ("int_var", 42),
+        ("float_var", 3.14),
+        ("bool_var", True),
+        ("list_var", [1, 2, 3]),
+        ("dict_var", {"key": "value"}),
+    ]
+
+    for var_name, var_value in test_cases:
+        message = tool.create_variable_message(var_name, var_value)
+
+        assert message.type == ToolInvokeMessage.MessageType.VARIABLE
+        assert message.message.variable_name == var_name
+        assert message.message.variable_value == var_value
+        assert message.message.stream is False