feat: bedrock encoder merge

[jamescalam]

PR Type

Bug fix, Enhancement, Tests, Documentation

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Description

• Fixed environment variable names for AWS credentials in BedrockEncoder.
• Added retry logic for handling expired tokens in BedrockEncoder.
• Refactored chunking logic into a separate method in BedrockEncoder.
• Improved error handling and logging in BedrockEncoder.
• Added comprehensive tests for BedrockEncoder, including retry logic, chunking functionality, and various initialization scenarios.
• Updated dependencies to include botocore in pyproject.toml.

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Changes walkthrough 📝

	Relevant files
Bug fix	bedrock.py Fix and enhance BedrockEncoder initialization and API calls semantic_router/encoders/bedrock.py Fixed environment variable names for AWS credentials. Added retry logic for handling expired tokens. Refactored chunking logic into a separate method. Improved error handling and logging. +112/-88
Tests	test_bedrock.py Add comprehensive tests for BedrockEncoder                              tests/unit/encoders/test_bedrock.py Added tests for new retry logic and chunking functionality. Added tests for various initialization scenarios. Improved test coverage for error handling. +151/-21
Dependencies	pyproject.toml Update dependencies to include botocore                                    pyproject.toml Added botocore as an optional dependency. Updated bedrock extra to include botocore. +3/-2

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[github-actions]

PR Description updated to latest commit (a93b348)

[github-actions]

PR Review 🔍

⏱️ Estimated effort to review [1-5]	4, because the PR involves multiple complex changes including refactoring, error handling, and retry logic, which require careful review to ensure correctness and robustness.
🧪 Relevant tests	Yes
⚡ Possible issues	Retry Logic Concern: The retry logic for handling expired tokens might not correctly reinitialize the client if the session token remains expired or invalid. This could lead to repeated failures without proper handling of the new token acquisition.
	Exception Handling: The broad exception handling in several methods could mask specific errors, making debugging more difficult. It's generally better to catch more specific exceptions where possible.
🔒 Security concerns	No

Code feedback:

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relevant file	semantic_router/encoders/bedrock.py
suggestion	Consider adding a backoff strategy for the retry logic to handle API rate limits or network issues more gracefully. This can prevent the system from being overwhelmed by repeated quick retries. [important]
relevant line	sleep(2**attempt)

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relevant file	semantic_router/encoders/bedrock.py
suggestion	It's recommended to handle specific exceptions from the Boto3 and Botocore libraries instead of a general exception, which can help in identifying the root cause of failures more accurately. [important]
relevant line	except Exception as e:

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relevant file	semantic_router/encoders/bedrock.py
suggestion	To improve the security and robustness of token handling, consider implementing a method to refresh the session token automatically when it expires, instead of relying on the environment variable that might not update in real-time. [important]
relevant line	self.session_token = os.getenv("AWS_SESSION_TOKEN")

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relevant file	semantic_router/encoders/bedrock.py
suggestion	Refactor the chunk_strings method to handle edge cases where the text might not need chunking or when the chunks are smaller than MAX_WORDS. This can prevent unnecessary processing and potential errors. [medium]
relevant line	def chunk_strings(self, strings, MAX_WORDS=20):

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[github-actions]

PR Code Suggestions ✨

Category	Suggestion	Score
Best practice	Use specific exceptions for better error handling Instead of catching a general Exception, specify the types of exceptions that are expected during client initialization. This will help in better error handling and debugging. semantic_router/encoders/bedrock.py [216] -except Exception as e: +except (SpecificExceptionType1, SpecificExceptionType2) as e: Suggestion importance[1-10]: 8 Why: Using specific exceptions improves error handling and debugging, making the code more robust and easier to maintain. This is a best practice that enhances code quality significantly.	8
Enhancement	Replace hardcoded retry delay with a configurable variable Replace the hardcoded retry delay with a variable that can be adjusted based on the environment or configuration settings. This will make the retry mechanism more flexible and maintainable. semantic_router/encoders/bedrock.py [220] -sleep(2**attempt) +sleep(retry_delay_seconds) Suggestion importance[1-10]: 7 Why: This suggestion improves the flexibility and maintainability of the retry mechanism by allowing the retry delay to be configurable. However, it is not a critical change and does not address a major bug or issue.	7
	Make the MAX_WORDS parameter adjustable in the chunk_strings method The method chunk_strings uses a hardcoded MAX_WORDS value for chunking, which might not be optimal for all scenarios. Consider making MAX_WORDS a parameter of the method to allow flexibility. semantic_router/encoders/bedrock.py [229] -def chunk_strings(self, strings, MAX_WORDS=20): +def chunk_strings(self, strings, max_words=20): Suggestion importance[1-10]: 6 Why: Making MAX_WORDS adjustable adds flexibility to the chunk_strings method, which can be beneficial for different use cases. However, it is a minor enhancement and does not address any critical issues.	6
Maintainability	Refactor error handling in retry logic for clarity Refactor the error handling in the retry logic to separate concerns and improve readability. Specifically, handle the token expiration and other client errors in different blocks or methods. semantic_router/encoders/bedrock.py [204-217] if error.response["Error"]["Code"] == "ExpiredTokenException": - logger.warning("Session token has expired. Retrying initialisation.") - try: - self.session_token = os.getenv("AWS_SESSION_TOKEN") - self.client = self._initialize_client( - self.access_key_id, - self.secret_access_key, - self.session_token, - self.region, - ) - except Exception as e: - raise ValueError(f"Bedrock client failed to reinitialise. Error: {e}") from e + handle_token_expiration() +else: + handle_client_error(error) Suggestion importance[1-10]: 7 Why: This refactoring improves code readability and maintainability by separating concerns in the error handling logic. While it enhances the structure of the code, it is not addressing a critical issue.	7