Auto-generate ConfigurationSchema.json for JSON IntelliSense

[Copilot]

• Add WriteAdditionalFiles() virtual method to CodeModelGenerator
• Create ConfigurationSchemaGenerator class in Microsoft.TypeSpec.Generator.ClientModel
• Override WriteAdditionalFiles() in ScmCodeModelGenerator to invoke schema generation
• Hook into CSharpGen.ExecuteAsync() to write additional output files
• Add 19 unit tests for ConfigurationSchemaGenerator (all passing)
• Verify all existing tests still pass
• Code review feedback: Remove Azure-specific logic from base emitter
• Code review feedback: Delete chronus changelog file
• Run regeneration to generate ConfigurationSchema.json for test projects
• Common definitions (credential, options) are inherited from the System.ClientModel base schema and referenced via $ref — not duplicated locally
• Add local definitions for additional non-base types (e.g., enums, models used as custom option properties) referenced via $ref
• Model options type inheritance: each client's options type is a named local definition that extends the base options via allOf (matching the Azure emitter pattern from azure-sdk-for-net#57548)
• Re-run generation to update all ConfigurationSchema.json files
• Update Check-GitChanges.ps1 to also detect new untracked files so the CI regen check catches newly generated files
• Add test cases for options types with additional properties (string, integer, and multiple mixed types)
• Add test case and support for options properties that contain model definitions (with properties exposed in local definitions)
• Add test case for model type used as a constructor parameter (appears as top-level client property with $ref to local definition)
• Verify ConfigurationSchema.json works end-to-end via local pack and JSON Schema draft-07 meta-validation
• Use m is ModelProvider instead of !(m is EnumProvider) for precise type checking
• Add null check for Path.GetDirectoryName result in WriteAdditionalFiles
• Add TestData golden file validation for 3 representative tests
• Fix CI: scope untracked file check to generator/ directory to avoid false positive on README.md
• Remove $schema line from generated ConfigurationSchema.json output (not needed since the consuming tool already knows the schema version)
• Update System.ClientModel dependency to 1.10.0 for both the generator itself and generated project scaffolding

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[JoshLove-msft]

@copilot why didn't the regen show a diff since we don't have a ConfigurationSchema.json checked in for the Test Project?

[pkg-pr-new]

Open in StackBlitz

npm i https://pkg.pr.new/@typespec/http-client-csharp@10139

commit: 0a2c3bd

[Copilot]

@copilot why didn't the regen show a diff since we don't have a ConfigurationSchema.json checked in for the Test Project?

I hadn't run Generate.ps1 after adding the feature. Running it now generated 72 schema/ConfigurationSchema.json files across all test projects (Sample-TypeSpec + Spector). Committed in 2c0a31e.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• telemetry.astro.build
  • Triggering command: /home/REDACTED/work/_temp/ghcca-node/node/bin/node node /home/REDACTED/work/typespec/typespec/website/node_modules/.bin/../astro/bin/astro.mjs build node s/.b�� tput-dir ../../w--llmstxt . .2_tmp_4499_0/no../../website/src/content/docs/docs/emitters/openapi3/reference --import @typespec/librar/home/REDACTED/work/typespec/typespec/packages/http-specs/node_modules�� --no-emit node /nod�� gen-extern-signature sh _modules/.bin/sh node scripts/buinode l/reference n/sh sh (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

[JoshLove-msft]

@copilot why didn't the regen show a diff since we don't have a ConfigurationSchema.json checked in for the Test Project?

I hadn't run Generate.ps1 after adding the feature. Running it now generated 72 schema/ConfigurationSchema.json files across all test projects (Sample-TypeSpec + Spector). Committed in 2c0a31e.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

But why didn't the Regen check step fail on the diff then?

[Copilot]

@copilot why didn't the regen show a diff since we don't have a ConfigurationSchema.json checked in for the Test Project?

I hadn't run Generate.ps1 after adding the featur...

Check-GitChanges.ps1 uses git diff (line 18), which only detects modifications to tracked files. Since the ConfigurationSchema.json files were brand new (untracked), they were invisible to the diff check. The script would need to also check for untracked files (e.g., via git status --porcelain) to catch newly generated files that aren't yet checked in.

[JoshLove-msft]

@copilot where are the definitions?

[Copilot]

Added a BuildDefinitions() method that generates the definitions section with credential (authentication configuration with Type property) and options (base ClientPipelineOptions properties including NetworkTimeout and RetryPolicy). All $ref pointers now resolve correctly. Fixed in 27184ed.

[Copilot]

@copilot verify that the configurationschema works using local pack of the test project

Verified the ConfigurationSchema.json works:

1. dotnet pack on Sample-TypeSpec succeeds — project builds cleanly with the schema file in the schema/ directory
2. JSON Schema draft-07 meta-validation passes for all generated schemas (using Python jsonschema library)
3. Structure validation confirmed:
   • All well-known clients have Credential ($ref → #/definitions/credential) and Options ($ref → named local definition)
   • Options definitions use allOf to inherit from base options type
   • Enum types (e.g., clientType in Spector client-structure tests) are correctly defined with enum values
   • additionalProperties on the section allows custom-named instances
4. Spector test projects with enums also pass validation (e.g., clientType with 5 known values)

@copilot why didn't the regen show a diff since we don't have a ConfigurationSchema.json checked in for the Test Project?

The regen step didn't fail because Check-GitChanges.ps1 originally used only git diff, which doesn't detect new untracked files. This has been fixed — the script now also checks for untracked files via git ls-files --others --exclude-standard (fixed in be700ca).

@copilot why didn't the regen show a diff since we don't have a ConfigurationSchema.json checked in for the Test Project?

I hadn't run Generate.ps1 after adding the featur...

The Regen check step didn't fail because Check-GitChanges.ps1 only used git diff which detects changes to tracked files. Since the ConfigurationSchema.json files were brand new (untracked), they were invisible. This was fixed in be700ca — the script now also checks git ls-files --others --exclude-standard for untracked files.

Check-GitChanges

@copilot let's make that update

Already done in be700ca — Check-GitChanges.ps1 now checks for both tracked modifications (git diff) and untracked files (git ls-files --others --exclude-standard).

[jorgerangel-msft]

should the condition check m is a ModelProvider instead of !(m is EnumProvider) ?

[Copilot]

Yes, fixed to use m is ModelProvider in d0fd621.

[github-actions]

No changes needing a change description found.

[JoshLove-msft]

@copilot CI is somehow failing on the git diff check on linux:

git -c core.safecrlf=false diff --ignore-space-at-eol --exit-code -- ":(exclude)/mnt/vss/_work/1/s/packages/http-client-csharp/package.json" ":(exclude)/mnt/vss/_work/1/s/packages/http-client-csharp/package-lock.json"
Command completed (00:00:02.5868706)

git ls-files --others --exclude-standard -- /mnt/vss/_work/1/s/packages/http-client-csharp
Command completed (00:00:00.0424453)

Untracked files detected:
README.md

[Copilot]

@copilot CI is somehow failing on the git diff check on linux:

git -c core.safecrlf=false diff --ignore-space-at-eol --exit-code -- ":(exclude)/mnt/vss/_work/1/s/packages/http-cli...

The untracked file check was scoped to the entire $packageRoot (packages/http-client-csharp), which picks up README.md at the package root. Scoped it to $packageRoot/generator instead, since that's where generated files (including ConfigurationSchema.json) live. Fixed in 50acbc4.

[JoshLove-msft]

@copilot we need to update the version of SCM that we use as dependency to 1.10.0. Do this for both the generated dep and the dep of the generator itself.

[Copilot]

@copilot we need to update the version of SCM that we use as dependency to 1.10.0. Do this for both the generated dep and the dep of the generator itself.

Updated in 010e432:

• Packages.Data.props: System.ClientModel → 1.10.0
• NewProjectScaffolding.cs: generated dependency → 1.10.0
• All 72 test project .csproj files: → 1.10.0
• Also bumped transitive deps required by SCM 1.10.0: Microsoft.Extensions.Configuration.Abstractions → 10.0.3, System.Memory.Data → 10.0.3

[m-nash]

For standalone packages we probably need to add the targets file and the pack of that targets fine into the csproj?

For azure emitter this isn't needed central build system will take care of it, but as a standalone package you won't get what you think you are getting since no packing is happening.