CLOUDP-292850: Investigate diff approach for Metric Collection

[yelizhenden-mdb]

Proposed changes

Jira ticket: CLOUDP-292850

PoC for Incremental Validation Framework
This PR introduces a Proof of Concept (PoC) for the Incremental Validation Framework, as outlined in the IPA Validation Framework Technical Design document

• This implementation uses a brute-force approach and does not prioritize optimizations.
• While the architecture could be improved, I’ve made an effort to separate functionality into distinct files and include comments for clarity.
• To better understand the code, I recommend reading the detailed description below before diving into the implementation

Key Findings and Implementation Steps:
Step 1: Splitting the Latest OpenAPI Version
The OpenAPI specification prior to the latest version is split by tags, with a separate file created for shared components.
Primary logic resides in split_oas.go.

Step 2: Detecting Changes
Changes are identified and classified into three cases: added, deleted, and modified. Primary logic resides in detect_changes.go file

• Components Changes:
  If any shared components are updated, the shared_components file must also be updated to reflect these changes.
  This file is later merged with the tag-split files for affected paths.

• Added Paths:
  If new paths are identified, tag-split files should be updated accordingly.
  If a directory with the corresponding tag name for new path doesn't exist, it will be created. Otherwise, the tag-related file is updated with the new path.
  Assumption: All endpoints within a path share the same tag.

• Deleted Paths:
  Deleted paths are extracted from the split files and placed into a separate deleted_spec.yaml file.
  Spectral validation will not run on split files if they have no additions or updates. Additionally, a tag will not be recorded as affectedTag if its only change is the deletion of a path.
  All deleted_spec.yaml files will be merged with the shared_components.yaml file. Results related to paths (but not components) in the merged file will be flagged asisDeleted=true.

• Deleted Components (Not Implemented, as suggestion)
  Components removed from the OpenAPI spec are extracted from the shared_components file and placed in a deleted_components.yaml file.
  Spectral validation will be run on deleted_components.yaml file and results will be flagged as isDeleted=true

• Modified Paths:
  Affected tags are tracked, and only the corresponding split files are updated.

Step 3: Incremental Validation
Only the affected tag-split files are merged with the shared_components.yaml file.
Spectral linting runs on merged files.
Future optimization: Components could be tailored to include only those referenced in the affected tag-split files.
Primary logic resides in main.go.

Output Examples:

• Tag-Split Files and Shared Components: Files prior to any modifications (based on detected changes) are included as examples under the split_specs directory.
• path_to_key_mapping.json: Provides a mapping of paths to their corresponding keys, including updates from detected changes.
• merged_spec.yaml: Demonstrates a merged specification for Monitoring and Logs tag-related paths along with the shared components file. This merge was necessary because the updated collectionName parameter is referenced in paths associated with the Monitoring and Logs tags. This file represents one of the merged outputs generated after detecting differences between the old and new versions.

Notes on Running the Code:

• The code is runnable but needs to be executed step by step due to a file flushing issue I couldn’t resolve at the moment.
• If you have any questions about running the code or encounter issues, feel free to reach out.
• Feedback and comments are always welcome!

Checklist

• I have signed the MongoDB CLA
• I have added tests that prove my fix is effective or that my feature works

Changes to Spectral

• I have read the README file for Spectral Updates

Further comments

[yelizhenden-mdb]

This file has:

• A new schema defined, named as TestSchema
• Two new paths defined
• OperationId of get method of /api/atlas/v2 path modified
• Schema example of parameter named collectionName is modified
  for testing purposes