Core: 6. Context serialization

This tutorial shows context serialization. First of all, let’s do all the necessary imports from DFF.

# installing dependencies
%pip install -q dff

Note: you may need to restart the kernel to use updated packages.

import logging

from dff.script import TRANSITIONS, RESPONSE, Context, Message
import dff.script.conditions as cnd

from dff.pipeline import Pipeline
from dff.utils.testing.common import (
    check_happy_path,
    is_interactive_mode,
    run_interactive_mode,
)

This function returns the user request number.

def response_handler(ctx: Context, _: Pipeline) -> Message:
    return Message(f"answer {len(ctx.requests)}")

# a dialog script
toy_script = {
    "flow_start": {
        "node_start": {
            RESPONSE: response_handler,
            TRANSITIONS: {("flow_start", "node_start"): cnd.true()},
        }
    }
}

# testing
happy_path = (
    (Message("hi"), Message("answer 1")),
    (Message("how are you?"), Message("answer 2")),
    (Message("ok"), Message("answer 3")),
    (Message("good"), Message("answer 4")),
)

Draft function that performs serialization.

def process_response(ctx: Context):
    ctx_json = ctx.model_dump_json()
    if isinstance(ctx_json, str):
        logging.info("context serialized to json str")
    else:
        raise Exception(f"ctx={ctx_json} has to be serialized to json string")

    ctx_dict = ctx.model_dump()
    if isinstance(ctx_dict, dict):
        logging.info("context serialized to dict")
    else:
        raise Exception(f"ctx={ctx_dict} has to be serialized to dict")

    if not isinstance(ctx, Context):
        raise Exception(f"ctx={ctx} has to have Context type")

pipeline = Pipeline.from_script(
    toy_script,
    start_label=("flow_start", "node_start"),
    post_services=[process_response],
)

if __name__ == "__main__":
    check_happy_path(pipeline, happy_path)
    if is_interactive_mode():
        run_interactive_mode(pipeline)

Service 'process_response_0' execution failed!
Traceback (most recent call last):
  File "/home/runner/work/dialog_flow_framework/dialog_flow_framework/dff/pipeline/service/service.py", line 151, in _run_as_service
    await self._run_handler(ctx, pipeline)
  File "/home/runner/work/dialog_flow_framework/dialog_flow_framework/dff/pipeline/service/service.py", line 118, in _run_handler
    await wrap_sync_function_in_async(self.handler, ctx)
  File "/home/runner/work/dialog_flow_framework/dialog_flow_framework/dff/pipeline/service/utils.py", line 25, in wrap_sync_function_in_async
    return func(*args, **kwargs)
  File "/tmp/ipykernel_16880/4050068440.py", line 2, in process_response
    ctx_json = ctx.model_dump_json()
  File "/home/runner/.cache/pypoetry/virtualenvs/dff-7eKxroBE-py3.9/lib/python3.9/site-packages/pydantic/main.py", line 358, in model_dump_json
    return self.__pydantic_serializer__.to_json(
pydantic_core._pydantic_core.PydanticSerializationError: Unable to serialize unknown type: <class 'function'>

Service 'process_response_0' execution failed!
Traceback (most recent call last):
  File "/home/runner/work/dialog_flow_framework/dialog_flow_framework/dff/pipeline/service/service.py", line 151, in _run_as_service
    await self._run_handler(ctx, pipeline)
  File "/home/runner/work/dialog_flow_framework/dialog_flow_framework/dff/pipeline/service/service.py", line 118, in _run_handler
    await wrap_sync_function_in_async(self.handler, ctx)
  File "/home/runner/work/dialog_flow_framework/dialog_flow_framework/dff/pipeline/service/utils.py", line 25, in wrap_sync_function_in_async
    return func(*args, **kwargs)
  File "/tmp/ipykernel_16880/4050068440.py", line 2, in process_response
    ctx_json = ctx.model_dump_json()
  File "/home/runner/.cache/pypoetry/virtualenvs/dff-7eKxroBE-py3.9/lib/python3.9/site-packages/pydantic/main.py", line 358, in model_dump_json
    return self.__pydantic_serializer__.to_json(
pydantic_core._pydantic_core.PydanticSerializationError: Unable to serialize unknown type: <class 'function'>

Service 'process_response_0' execution failed!
Traceback (most recent call last):
  File "/home/runner/work/dialog_flow_framework/dialog_flow_framework/dff/pipeline/service/service.py", line 151, in _run_as_service
    await self._run_handler(ctx, pipeline)
  File "/home/runner/work/dialog_flow_framework/dialog_flow_framework/dff/pipeline/service/service.py", line 118, in _run_handler
    await wrap_sync_function_in_async(self.handler, ctx)
  File "/home/runner/work/dialog_flow_framework/dialog_flow_framework/dff/pipeline/service/utils.py", line 25, in wrap_sync_function_in_async
    return func(*args, **kwargs)
  File "/tmp/ipykernel_16880/4050068440.py", line 2, in process_response
    ctx_json = ctx.model_dump_json()
  File "/home/runner/.cache/pypoetry/virtualenvs/dff-7eKxroBE-py3.9/lib/python3.9/site-packages/pydantic/main.py", line 358, in model_dump_json
    return self.__pydantic_serializer__.to_json(
pydantic_core._pydantic_core.PydanticSerializationError: Unable to serialize unknown type: <class 'function'>

Service 'process_response_0' execution failed!
Traceback (most recent call last):
  File "/home/runner/work/dialog_flow_framework/dialog_flow_framework/dff/pipeline/service/service.py", line 151, in _run_as_service
    await self._run_handler(ctx, pipeline)
  File "/home/runner/work/dialog_flow_framework/dialog_flow_framework/dff/pipeline/service/service.py", line 118, in _run_handler
    await wrap_sync_function_in_async(self.handler, ctx)
  File "/home/runner/work/dialog_flow_framework/dialog_flow_framework/dff/pipeline/service/utils.py", line 25, in wrap_sync_function_in_async
    return func(*args, **kwargs)
  File "/tmp/ipykernel_16880/4050068440.py", line 2, in process_response
    ctx_json = ctx.model_dump_json()
  File "/home/runner/.cache/pypoetry/virtualenvs/dff-7eKxroBE-py3.9/lib/python3.9/site-packages/pydantic/main.py", line 358, in model_dump_json
    return self.__pydantic_serializer__.to_json(
pydantic_core._pydantic_core.PydanticSerializationError: Unable to serialize unknown type: <class 'function'>

(user) >>> text='hi'
 (bot) <<< text='answer 1'
(user) >>> text='how are you?'
 (bot) <<< text='answer 2'
(user) >>> text='ok'
 (bot) <<< text='answer 3'
(user) >>> text='good'
 (bot) <<< text='answer 4'