Add Mermaid diagram visualization for application graphs

[Copilot]

Description

Enables GitHub-native visualization of Radius application graphs using Mermaid diagrams. The existing text format remains the default.

Implementation

• CLI Integration: Added --format flag to rad app graph command accepting text (default) or mermaid
• Visualization Engine: New displayMermaid() function generates Mermaid TB graph syntax with:
  • Node shapes by resource type (rectangles for containers, cylinders for datastores, diamonds for gateways)
  • Color-coded styling (blue containers, orange datastores, purple gateways)
  • Sanitized node IDs and shortened type labels
• Testing: 22 test cases covering empty graphs, simple/complex applications, edge cases

Usage

# Generate Mermaid diagram
rad app graph my-app --format mermaid

# Output to docs
rad app graph my-app --format mermaid > docs/architecture.md

Example Output

graph TB
    app["Application: demo-app"]
    frontend["frontend<br/>containers"]
    backend["backend<br/>containers"]
    postgres[("postgres<br/>sqlDatabases")]
    
    frontend --> backend
    backend --> postgres
    
    classDef container fill:#e1f5ff,stroke:#0078d4,stroke-width:2px
    classDef datastore fill:#fff4ce,stroke:#d83b01,stroke-width:2px

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Type of change

• This pull request adds or changes features of Radius and has an approved issue (issue link required).

Contributor checklist

Please verify that the PR meets the following requirements, where applicable:

• An overview of proposed schema changes is included in a linked GitHub issue.
  • Not applicable
• A design document PR is created in the design-notes repository, if new APIs are being introduced.
  • Not applicable
• The design document has been reviewed and approved by Radius maintainers/approvers.
  • Not applicable
• A PR for the samples repository is created, if existing samples are affected by the changes in this PR.
  • Not applicable
• A PR for the documentation repository is created, if the changes in this PR affect the documentation or any user facing updates are made.
  • Yes
• A PR for the recipes repository is created, if existing recipes are affected by the changes in this PR.
  • Not applicable

Original prompt

write code that will take an existing radius application definition and app graph that will visualize the graph in the github style

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[nicolejms]

@copilot update the app graph definition to include connection information such as ip address/port and location and version of the file from which the graph element is generated by

[Copilot]

@copilot update the app graph definition to include connection information such as ip address/port and location and version of the file from which the graph element is generated by

I'd like to clarify what information should be included in the graph visualization.

Currently, the ApplicationGraphResource structure exposes limited fields (ID, Name, Type, Connections, ProvisioningState). The additional details you mentioned (IP address, port, location, file version) exist in the underlying resource data but aren't currently exposed through the graph API.

Could you clarify:

1. IP address/port: Should this come from the container's port configuration or from the deployed output resources?
2. Location: Do you mean the deployment location (e.g., resource group, region) or the Bicep file path?
3. Version: Is this the API version of the resource type, or a version property from the resource itself?

Would you like me to:

• Add this information to the Mermaid node labels/tooltips (if the data is available)?
• Or do you need changes to the backend graph API to expose more resource properties first?

[nicolejms]

@copilot 1. containers port configuration, 2. the location of the bicep file path, 3. the github file version of the recipe

[Copilot]

@copilot 1. containers port configuration, 2. the location of the bicep file path, 3. the github file version of the recipe

The requested information (container ports, Bicep file path, recipe version) exists in the resource properties but isn't currently exposed through the ApplicationGraphResource API structure that the visualization uses.

To add this information, we need backend API changes first:

Backend Changes Needed (in pkg/corerp/frontend/controller/applications/graph_util.go):

1. Extract container port configuration from resource.Properties["container"]["ports"]
2. Extract recipe information from resource.Properties["status"]["recipe"] (TemplatePath and TemplateVersion)
3. Add new fields to ApplicationGraphResource or include as metadata

Alternative Approach:
I can enhance the visualization to show the information that IS currently available:

• Resource ID (which includes the full path)
• Resource type
• Provisioning state
• Output resources

Would you like me to:

1. Create a separate issue/PR for the backend API changes to expose these properties?
2. Or document what changes are needed and proceed with the current available data?

The backend changes would require modifying the API contract, which may need design review from maintainers.