fix: ignore non-serializable params when hashing pipeline objects (#3842)

* ignore non-serializable params when hashing pipeline objects

* make tests more clear

haystack/pipelines/base.py

@@ -2288,7 +2288,8 @@ class Pipeline:
         return datetime.datetime.now(datetime.timezone.utc) - self.init_time
 
     def send_pipeline_event(self, is_indexing: bool = False):
-        fingerprint = sha1(json.dumps(self.get_config(), sort_keys=True).encode()).hexdigest()
+        json_repr = json.dumps(self.get_config(), sort_keys=True, default=lambda o: "<not serializable>")
+        fingerprint = sha1(json_repr.encode()).hexdigest()
         send_custom_event(
             "pipeline",
             payload={

test/pipelines/test_pipeline.py

@@ -1,19 +1,17 @@
-from copy import deepcopy
-from pathlib import Path
-import os
 import ssl
 import json
 import platform
 import sys
+import datetime
 from typing import Tuple
+from copy import deepcopy
+from unittest import mock
 
 import pytest
 from requests import PreparedRequest
 import responses
 import logging
-from transformers import pipeline
 import yaml
-import pandas as pd
 
 from haystack import __version__
 from haystack.document_stores.deepsetcloud import DeepsetCloudDocumentStore
@@ -36,16 +34,13 @@ from haystack.pipelines import (
     DocumentSearchPipeline,
     QuestionGenerationPipeline,
     MostSimilarDocumentsPipeline,
-    BaseStandardPipeline,
 )
 from haystack.pipelines.config import validate_config_strings, get_component_definitions
 from haystack.pipelines.utils import generate_code
 from haystack.errors import PipelineConfigError
-from haystack.nodes import PreProcessor, TextConverter, QuestionGenerator
+from haystack.nodes import PreProcessor, TextConverter
 from haystack.utils.deepsetcloud import DeepsetCloudError
-from haystack import Document, Answer
-from haystack.nodes.other.route_documents import RouteDocuments
-from haystack.nodes.other.join_answers import JoinAnswers
+from haystack import Answer
 
 from ..conftest import (
     MOCK_DC,
@@ -2158,3 +2153,44 @@ def test_fix_to_pipeline_execution_when_join_follows_join():
     res = pipeline.run(query="Alpha Beta Gamma Delta")
     documents = res["documents"]
     assert len(documents) == 4  # all four documents should be found
+
+
+def test_send_pipeline_event():
+    """
+    Test the event can be sent and the internal fields are correctly set
+    """
+    pipeline = Pipeline()
+    pipeline.add_node(MockNode(), name="mock_node", inputs=["Query"])
+
+    with mock.patch("haystack.pipelines.base.send_custom_event") as mocked_send:
+        today_at_midnight = datetime.datetime.combine(datetime.datetime.now(), datetime.time.min, datetime.timezone.utc)
+        pipeline.send_pipeline_event()
+        mocked_send.assert_called_once()
+        assert pipeline.time_of_last_sent_event == today_at_midnight
+        assert pipeline.last_window_run_total == 0
+
+
+def test_send_pipeline_event_unserializable_param():
+    """
+    Test the event can be sent even when a certain component was initialized with a
+    non-serializable parameter, see https://github.com/deepset-ai/haystack/issues/3833
+    """
+
+    class CustomNode(MockNode):
+        """A mock node that can be inited passing a param"""
+
+        def __init__(self, param):
+            self.param = param
+
+    # create a custom node passing a parameter that can't be serialized (an empty set)
+    custom_node = CustomNode(param=set())
+
+    pipeline = Pipeline()
+    pipeline.add_node(custom_node, name="custom_node", inputs=["Query"])
+
+    with mock.patch("haystack.pipelines.base.send_custom_event") as mocked_send:
+        today_at_midnight = datetime.datetime.combine(datetime.datetime.now(), datetime.time.min, datetime.timezone.utc)
+        pipeline.send_pipeline_event()
+        mocked_send.assert_called_once()
+        assert pipeline.time_of_last_sent_event == today_at_midnight
+        assert pipeline.last_window_run_total == 0