Proposal: Enhance Bake LSP Support

[colinhemmings]

Problem

The current LSP support for docker-bake.hcl files in the Docker DX VS Code extension is functional but limited:

• Syntax: highlighting, code completion, formatting
• Hover information only shows the type, without any helpful documentation or usage guidance.
• There’s no support for visualizing the inheritance hierarchy of targets (e.g., inherits = ["_common"]), making it hard to reason about multi-target setups.
• Outline a view outline of Bake file targets
• Image references inside fields like tags = ["ghcr.io/abc/def"] are plain strings with no ability to click and inspect the image source (e.g., opening the URL in a browser).
• Navigation from variable references to definitions and from docker-bake.hcl build stage references to corresponding Dockerfile declarations

These limitations reduce developer productivity and make it harder for users—especially those new to docker-bake.hcl—to understand, refactor, and explore their configurations confidently.

Proposed Solution

Enhance the Bake LSP implementation with the following capabilities:

1. Hover and code completion improvements
   • Show helpful documentation (not just the type) when hovering over attributes.
   • Include usage examples, common values, and links to relevant docs.
2. Target hierarchy visualization
   • Display how a target inherits from others (inherits = ["_common"]), similar to class inheritance in object-oriented languages.
   • Optional tree/graph view or inline hover/tooltip linking to inherited targets.
3. Rename support
   • Allow developers to rename a target and automatically update all references (especially inherited relationships) across the file.
4. Linkable image tags
   • Make values like tags = ["ghcr.io/abc/def"] clickable, opening the corresponding container registry page in the browser.