Fix AttributeError Dict Object Has No Attribute Is_xml_model In Adaptive Cards Search

by Axel Sørensen 86 views

Hey guys! Today, we're diving deep into a tricky bug encountered while working with Adaptive Cards in Teams AI. Specifically, this issue pops up during search operations and throws an AttributeError: 'dict' object has no attribute 'is_xml_model'. It's a mouthful, but don't worry, we'll break it down and explore a workaround. Let's get started!

Understanding the Issue

The Error Message

First, let's dissect the error message. The traceback points to a problem within the msrest.serialization library, which is used for serializing and deserializing data in Microsoft REST API clients. The error occurs when the code tries to determine if an object should be serialized as XML. It expects the object to have an is_xml_model attribute, but instead, it finds a dictionary, which doesn't have this attribute. This usually happens when the data being processed isn't in the expected format or when there's a mismatch in how the data is being handled.

AttributeError: 'dict' object has no attribute 'is_xml_model'

This error arises within the Teams AI library, specifically when processing search results for Adaptive Cards. When your bot returns a list of AdaptiveCardsSearchResult objects, the library attempts to serialize these results into a format suitable for the Adaptive Card. However, the serialization process stumbles when it encounters a dictionary where it expects an object with an is_xml_model attribute.

Root Cause Analysis

To really nail down what's going on, we need to look at the code snippet where the error occurs. The issue arises when the AdaptiveCardsSearchResult objects are being serialized. The msrest library's serialization logic expects certain objects to have an is_xml_model attribute, which helps determine how the object should be serialized (either as JSON or XML). When a dictionary is encountered instead of an object with this attribute, the process fails.

This typically indicates a mismatch between the expected data structure and the actual data being processed. In this case, the serializer is expecting an object that explicitly defines its XML serialization behavior, but it's receiving a plain Python dictionary. This can happen if the AdaptiveCardsSearchResult objects are not being correctly transformed into the expected format before serialization.

Impact

The practical impact of this bug is that the search functionality in your Adaptive Cards-based bot will fail. Users won't be able to see search results, making the type-ahead feature unusable. This can significantly degrade the user experience and limit the bot's functionality.

Reproduction Steps

To reproduce this bug, you can follow these steps:

  1. Clone the microsoft/teams-ai repository from GitHub:

    git clone https://github.com/microsoft/teams-ai.git

  2. Navigate to the 03.adaptiveCards.a.typeAheadBot example:

    cd teams-ai/python/samples/03.adaptiveCards.a.typeAheadBot/src

  3. Implement the provided code snippet for the @app.adaptive_cards.search handler.

  4. Run the bot and interact with it in a Teams environment. Trigger the search functionality by typing in the search input field of the Adaptive Card.

  5. Observe the traceback in your console, which will show the AttributeError: 'dict' object has no attribute 'is_xml_model'.

Code Snippet Causing the Issue

Here’s the code snippet that triggers the bug:

@app.adaptive_cards.search("npmpackages")
async def search_npm_package(
    _context: TurnContext, _state: AppTurnState, query: Query[AdaptiveCardsSearchParams]
):
    search_query = query.parameters.query_text
    count = query.count
    async with aiohttp.ClientSession() as session:
        async with session.get(
            f"http://registry.npmjs.com/-/v1/search?text={search_query}&size={count})"
        ) as response:
            data = await response.json()
            npm_packages = []
            for obj in data["objects"]:
                result = AdaptiveCardsSearchResult(
                    title= obj["package"]["name"],
                    value= f"{obj['package']['name']} - {obj['package'].get('description','')}",
                )
                npm_packages.append(result)
            return npm_packages

The key part of this code is where the AdaptiveCardsSearchResult objects are created and returned. The issue lies in how these objects are being processed internally by the Teams AI library during serialization.

Temporary Workaround

Alright, let's talk about how to get around this pesky bug. The provided workaround involves creating custom classes (SearchResponseValue and SearchResponse) that conform to the expected structure for the response. This bypasses the problematic serialization logic that causes the AttributeError. Here’s the code:

from botbuilder.schema import Activity
from botbuilder.core import InvokeResponse, TurnContext
from msrest.serialization import Model

class SearchResponseValue(Model):
    _attribute_map = {"results": {"key": "results", "type": "[object]"}}
    def __init__(self, results: list[dict]):
        self.results = results

class SearchResponse(Model):
    _attribute_map = {
        "type": {"key": "type", "type": "str"},
        "value": {"key": "value", "type": "SearchResponseValue"},
    }
    def __init__(self, results: list[dict]):
        self.type = "application/vnd.microsoft.search.searchResponse"
        self.value = SearchResponseValue(results)

# inside the def....
    invoke_response = InvokeResponse(status=200, body=SearchResponse(results))

    context.turn_state[context._INVOKE_RESPONSE_KEY] = invoke_response

    await context.send_activity(
        Activity(
            type="invokeResponse", value=invoke_response
        )
    )
    # Return an empty list to bypass the internal working of the adaptive card search thus avoiding the serialisation bug.
    return []

Explanation of the Workaround

  1. Custom Classes: The SearchResponseValue and SearchResponse classes are defined using msrest.serialization.Model. These classes help structure the search response in a way that the serializer expects.

  2. Attribute Mapping: The _attribute_map dictionaries define how the class attributes map to the JSON keys. This is crucial for serialization.

  3. Response Construction: Inside your search handler, you create an instance of SearchResponse with the search results. This formats the results into a structure that avoids the serialization bug.

  4. Invoke Response: An InvokeResponse is created with the SearchResponse as the body. This is the response that will be sent back to the client.

  5. Bypassing Internal Logic: The workaround returns an empty list ([]) to bypass the internal serialization logic that triggers the bug. This is a bit of a hack, but it works!

How to Implement the Workaround

To implement this workaround, follow these steps:

  1. Define Custom Classes: Add the SearchResponseValue and SearchResponse classes to your code.

  2. Modify Search Handler: Update your search handler to use these classes to construct the response.

  3. Return Empty List: Ensure that your search handler returns an empty list to bypass the problematic serialization.

This workaround ensures that the search results are correctly formatted and serialized, avoiding the AttributeError and allowing the type-ahead functionality to work as expected. It's not the most elegant solution, but it gets the job done until a proper fix is available.

Additional Information and Context

Language and Version

This issue was encountered while using Python with the latest version of the Teams AI library (1.8.1 at the time of reporting). This context is important because the bug might be specific to this version or language.

  • Language: Python
  • Version: Latest (1.8.1)

Long-Term Solution

While the workaround is effective, it's essential to address the underlying issue in the Teams AI library. A proper fix would involve correcting the serialization logic to handle AdaptiveCardsSearchResult objects correctly, without relying on custom classes and bypassing internal logic. It's advisable to keep an eye on the Teams AI library's issue tracker and release notes for updates related to this bug.

Conclusion

So, there you have it! We've dissected the AttributeError: 'dict' object has no attribute 'is_xml_model' bug in Teams AI when dealing with Adaptive Cards search results. We've explored the error, understood the root cause, and implemented a temporary workaround. While this workaround isn't perfect, it'll help you keep your bot running smoothly until a permanent fix is released. Remember, in the world of software development, bugs are just another challenge to overcome. Keep coding, and stay curious!