fix custom messenger interface

tests/pipeline/test_tutorials.py

@@ -3,7 +3,6 @@
 
 from tests.test_utils import get_path_from_tests_to_current_dir
 from dff.utils.testing import check_happy_path, HAPPY_PATH
-from dff.script import Message
 
 dot_path_to_addon = get_path_from_tests_to_current_dir(__file__, separator=".")
 
@@ -19,22 +18,14 @@
         "4_groups_and_conditions_full",
         "5_asynchronous_groups_and_services_basic",
         "5_asynchronous_groups_and_services_full",
-        "6_custom_messenger_interface",
-        "7_extra_handlers_basic",
-        "7_extra_handlers_full",
-        "8_extra_handlers_and_extensions",
+        "6_extra_handlers_basic",
+        "6_extra_handlers_full",
+        "7_extra_handlers_and_extensions",
     ],
 )
 def test_tutorials(tutorial_module_name: str):
     try:
         tutorial_module = importlib.import_module(f"tutorials.{dot_path_to_addon}.{tutorial_module_name}")
     except ModuleNotFoundError as e:
         pytest.skip(f"dependencies unavailable: {e.msg}")
-    if tutorial_module_name == "6_custom_messenger_interface":
-        happy_path = tuple(
-            (req, Message(misc={"webpage": tutorial_module.construct_webpage_by_response(res.text)}))
-            for req, res in HAPPY_PATH
-        )
-        check_happy_path(tutorial_module.pipeline, happy_path)
-    else:
-        check_happy_path(tutorial_module.pipeline, HAPPY_PATH)
+    check_happy_path(tutorial_module.pipeline, HAPPY_PATH)

tutorials/messengers/web_api_interface/1_fastapi.py

@@ -1,6 +1,6 @@
 # %% [markdown]
 """
-# Web API: 1. FastAPI
+# Web API: 2. FastAPI
 
 This tutorial shows how to create an API for DFF using FastAPI.
 
@@ -10,6 +10,7 @@
 # %pip install dff uvicorn fastapi
 
 # %%
+from dff.messengers.common.interface import CallbackMessengerInterface
 from dff.script import Message
 from dff.pipeline import Pipeline
 from dff.utils.testing import TOY_SCRIPT_ARGS, is_interactive_mode
@@ -18,9 +19,51 @@
 from pydantic import BaseModel
 from fastapi import FastAPI
 
+# %% [markdown]
+"""
+Messenger interfaces establish communication between users and the pipeline.
+They manage message channel initialization and termination
+as well as pipeline execution on every user request.
+There are two built-in messenger interface types (that may be overridden):
+
+* `PollingMessengerInterface` - Starts polling for user requests
+        in a loop upon initialization,
+        it has following methods:
+    * `_request()` - Method that is executed in a loop,
+        should return list of tuples: (user request, unique dialog id).
+    * `_respond(responses)` - Method that is executed in a loop
+        after all user requests processing,
+        accepts list of dialog `Contexts`.
+    * `_on_exception(e)` - Method that is called on
+        exception that happens in the loop,
+        should catch the exception
+        (it is also called on pipeline termination).
+    * `connect(pipeline_runner, loop, timeout)` -
+            Method that is called on connection to message channel,
+            accepts pipeline_runner (a callback, running pipeline).
+    * loop - A function to be called on each loop
+            execution (should return True to continue polling).
+    * timeout - Time in seconds to wait between loop executions.
+
+* `CallbackMessengerInterface` - Creates message channel
+        and provides a callback for pipeline execution,
+        it has following method:
+    * `on_request(request, ctx_id)` - Method that should be called each time
+        user provides new input to pipeline,
+        returns dialog Context.
+
+`CLIMessengerInterface` is also
+    a messenger interface that overrides `PollingMessengerInterface` and
+    provides default message channel between pipeline and console/file IO.
+
+Here the default `CallbackMessengerInterface` is used to setup
+communication between the pipeline on the server side and the messenger client.
+"""
 
 # %%
-pipeline = Pipeline.from_script(*TOY_SCRIPT_ARGS)
+messenger_interface = CallbackMessengerInterface()
+# CallbackMessengerInterface instantiating the dedicated messenger interface
+pipeline = Pipeline.from_script(*TOY_SCRIPT_ARGS, messenger_interface=messenger_interface)
 
 
 # %%
@@ -37,13 +80,14 @@ async def respond(
     user_id: str,
     user_message: Message,
 ):
-    context = await pipeline._run_pipeline(user_message, user_id)  # run in async
+    context = messenger_interface.on_request(user_message, user_id)
     return {"user_id": user_id, "response": context.last_response}
 
 
 # %%
 if __name__ == "__main__":
     if is_interactive_mode():  # do not run this during doc building
+        pipeline.run()
         uvicorn.run(
             app,
             host="127.0.0.1",

tutorials/messengers/web_api_interface/2_websocket_chat.py

@@ -1,6 +1,6 @@
 # %% [markdown]
 """
-# Web API: 2. WebSocket Chat
+# Web API: 3. WebSocket Chat
 
 This tutorial shows how to create a Web chat on FastAPI using websockets.
 
@@ -19,19 +19,19 @@
 # %pip install dff uvicorn fastapi
 
 # %%
+from dff.messengers.common.interface import CallbackMessengerInterface
 from dff.script import Message
 from dff.pipeline import Pipeline
-from dff.utils.testing import TOY_SCRIPT, is_interactive_mode
+from dff.utils.testing import TOY_SCRIPT_ARGS, is_interactive_mode
 
 import uvicorn
 from fastapi import FastAPI, WebSocket, WebSocketDisconnect
 from fastapi.responses import HTMLResponse
 
 
 # %%
-pipeline = Pipeline.from_script(
-    TOY_SCRIPT, ("greeting_flow", "start_node"), ("greeting_flow", "fallback_node")
-)
+messenger_interface = CallbackMessengerInterface()
+pipeline = Pipeline.from_script(*TOY_SCRIPT_ARGS, messenger_interface=messenger_interface)
 
 
 # %%
@@ -86,7 +86,7 @@ async def websocket_endpoint(websocket: WebSocket, client_id: int):
             data = await websocket.receive_text()
             await websocket.send_text(f"User: {data}")
             request = Message(text=data)
-            context = await pipeline._run_pipeline(request, client_id)
+            context = messenger_interface.on_request(request, client_id)
             response = context.last_response.text
             if response is not None:
                 await websocket.send_text(f"Bot: {response}")
@@ -99,6 +99,7 @@ async def websocket_endpoint(websocket: WebSocket, client_id: int):
 # %%
 if __name__ == "__main__":
     if is_interactive_mode():  # do not run this during doc building
+        pipeline.run()
         uvicorn.run(
             app,
             host="127.0.0.1",

tutorials/messengers/web_api_interface/3_load_testing_with_locust.py

@@ -1,6 +1,6 @@
 # %% [markdown]
 """
-# Web API: 3. Load testing with Locust
+# Web API: 4. Load testing with Locust
 
 This tutorial shows how to use an API endpoint created in the FastAPI tutorial in load testing.
 """

tutorials/messengers/web_api_interface/4_streamlit_chat.py

@@ -1,5 +1,5 @@
 # %% [markdown]
-# # Web API: 4. Streamlit chat interface
+# # Web API: 5. Streamlit chat interface
 #
 # This tutorial shows how to use an API endpoint created in the FastAPI tutorial
 # in a Streamlit chat.

tutorials/pipeline/7_extra_handlers_basic.py → tutorials/pipeline/6_extra_handlers_basic.py

@@ -1,6 +1,6 @@
 # %% [markdown]
 """
-# 7. Extra Handlers (basic)
+# 6. Extra Handlers (basic)
 
 The following tutorial shows extra handlers possibilities and use cases.
 """

tutorials/pipeline/7_extra_handlers_full.py → tutorials/pipeline/6_extra_handlers_full.py

@@ -1,6 +1,6 @@
 # %% [markdown]
 """
-# 7. Extra Handlers (full)
+# 6. Extra Handlers (full)
 
 The following tutorial shows extra handlers possibilities and use cases.
 """

tutorials/pipeline/8_extra_handlers_and_extensions.py → tutorials/pipeline/7_extra_handlers_and_extensions.py

@@ -1,6 +1,6 @@
 # %% [markdown]
 """
-# 8. Extra Handlers and Extensions
+# 7. Extra Handlers and Extensions
 
 The following tutorial shows how pipeline can be extended
 by global extra handlers and custom functions.

tutorials/stats/2_pipeline_integration.py

@@ -3,7 +3,7 @@
 # 2. Pipeline Integration
 
 In the DFF ecosystem, extractor functions act as regular extra handlers (
-[see the pipeline module documentation](%doclink(tutorial,pipeline.7_extra_handlers_basic))
+[see the pipeline module documentation](%doclink(tutorial,pipeline.6_extra_handlers_basic))
 ).
 Hence, you can decorate any part of your pipeline, including services,
 service groups and the pipeline as a whole, to obtain the statistics