Feature Overview (aka. Goal Summary)  

Enhance the oc-mirror v2 to discover and mirror container images referenced within environment variables of deployment templates. 

Goals (aka. expected user outcomes)

• Users can mirror all necessary container images referenced within environment variables of deployment templates, including operand images, for operator-based applications in air-gapped environments.
• oc-mirror v2 accurately identifies and mirrors only valid container image references within environment variables, ignoring non-image values.
• Improved reliability of oc-mirror v2 when processing environment variables.
• Reduced manual intervention needed to mirror all required images.

Background

Operator-based applications commonly employ a dynamic runtime deployment strategy for operand images.  These images are often specified through environment variables within the operator controller's Deployment template.  

Currently, the oc-mirror v2 utilizes predefined expressions and user-defined imagePaths to locate images within Helm charts.  However, the existing imagePaths expressions lack the specificity required for environment variables, capturing all values arbitrarily.  This leads to failures when oc-mirror v2 encounters non-image values within the environment variables. 

This feature is aimed at improving the reliability of oc-mirror v2 when processing environment variables with non-image values and enhanced imagePaths expressions to filter environment variables.

Requirements (aka. Acceptance Criteria):

• Graceful error handling:
  • Ignore environment variables whose values are not valid image references without causing failures.
  • Provide informative warnings or logs when non-image values are encountered.

• Environment variable filtering:
  • Support filtering environment variables based on naming conventions with enhanced imagePaths expressions similar to regular expression or alternative methods.

• Testing:
  • Comprehensive unit and integration tests are created to ensure the accuracy and reliability of the new functionality.
  • Test with a variety of environment variable naming conventions and image reference formats.

Documentation Considerations

• Update oc-mirror v2 documentation to reflect the new functionality.
• Provide clear examples of how to use the enhanced imagePaths expressions or filtering mechanisms.
• Include troubleshooting information for common issues related to environment variable image mirroring, e.g., encountering non-image values within the environment variables.