feat: add a protected /api/version endpoint

[bsaurusrex]

What

Adds GET /api/version, which returns the running Tinyauth version:

{ "status": 200, "message": "Success", "version": "v5.x.y" }

Why

Closes #1160. An external update checker / monitoring tool (e.g. Argus) needs a way to read the installed version. In the issue you noted a public version endpoint is a security concern and that you'd probably "add a new protected endpoint for /api/version" — this implements exactly that.

Behaviour / security

• The handler requires an authenticated user context. An unauthenticated (or merely present-but-unauthenticated, e.g. Tailscale Authenticated: false) request gets the standard { "status": 401, "message": "Unauthorized" } body, with no version leaked.
• The route is not added to contextSkipPathsPrefix, so the context middleware still runs and populates the user context; only authenticated callers see the version.
• No change to any existing endpoint or default behaviour; purely additive.

Tests

TestContextController gains three cases for /api/version: unauthorized (no context), unauthenticated context, and authorized (returns model.Version). go vet, go test ./..., go test -race, and a GOOS=windows build all pass.

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Summary by CodeRabbit

• New Features
  • Added a version endpoint that returns the application’s current version for authenticated requests.
  • Requests without an authenticated context receive an unauthorized response and do not receive version information.
  • The endpoint responds with the version and a status message, allowing clients to distinguish successful and unauthorized requests.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

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📥 Commits

Reviewing files that changed from the base of the PR and between 8e5aa14 and 07d9be5.

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📒 Files selected for processing (1)

• internal/controller/context_controller.go

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🚧 Files skipped from review as they are similar to previous changes (1)

• internal/controller/context_controller.go

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📝 Walkthrough

Walkthrough

The controller adds a protected /api/version endpoint. Authenticated requests receive the installed version with HTTP 200. Requests without an authenticated context receive HTTP 401.

Changes

Version endpoint

Layer / File(s)	Summary
Response contract and route internal/controller/context_controller.go	Adds the VersionResponse shape and registers the protected version route.
Authentication and version response internal/controller/context_controller.go, internal/controller/context_controller_test.go	Returns HTTP 401 when context creation fails or the context is unauthenticated. Authenticated requests receive model.Version with HTTP 200. Tests cover these cases.

Estimated code review effort: 2 (Simple) | ~10 minutes

Change: Feature

Sequence Diagram(s)

sequenceDiagram
  participant Client
  participant Router
  participant versionHandler
  participant UserContext
  participant model.Version
  Client->>Router: GET /api/version
  Router->>versionHandler: Dispatch protected route
  versionHandler->>UserContext: Create user context
  alt Context is authenticated
    versionHandler->>model.Version: Read installed version
    versionHandler-->>Client: HTTP 200 with success response and version
  else Context creation fails or context is unauthenticated
    versionHandler-->>Client: HTTP 401 with Unauthorized response
  end

Loading

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Merge Risk: 🔵 Low · up to 07d9b

Tools expecting the version from /api/context/app still cannot obtain it there. The endpoint choice should be accepted explicitly or changed before merging.

🚥 Pre-merge checks | ✅ 2 | ❌ 3

❌ Failed checks (3 warnings)

Check name	Status	Explanation	Resolution
Linked Issues check		Issue #1160 requires the installed version in the /api/context/app response. The whole-PR diff adds VersionResponse and GET /api/version, but it does not change AppContextResponse or `appConte…	Add the installed version to the /api/context/app response and add tests that verify the field. Keep the separate endpoint only if issue #1160 explicitly changes its requested API scope.
Out of Scope Changes check		The whole-PR diff adds a separate protected GET /api/version contract and tests. Issue #1160 specifies /api/context/app as the endpoint for the version. The separate route is not connected to that…	Remove the separate /api/version implementation and tests, or obtain an explicit scope update for issue #1160 before retaining them.
Docstring Coverage		Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 2 functions across 2 files.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Description Check		Check skipped - CodeRabbit’s high-level summary is enabled.
Title check		The title clearly and concisely describes the main change: adding a protected /api/version endpoint.

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Full details: Linked Issues check

Explanation

Issue #1160 requires the installed version in the /api/context/app response. The whole-PR diff adds VersionResponse and GET /api/version, but it does not change AppContextResponse or appContextHandler. The required /api/context/app contract and its tests remain incomplete.

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Full details: Out of Scope Changes check

Explanation

The whole-PR diff adds a separate protected GET /api/version contract and tests. Issue #1160 specifies /api/context/app as the endpoint for the version. The separate route is not connected to that specified endpoint.

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[coderabbitai]

Actionable comments posted: 1

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• 🪄 Fix CodeRabbit comments on this PR

🤖 Prompt to fix review comments

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Inline comments:
Review comments at @internal/controller/context_controller.go:
- Around line 116-118: Add the installed version to the `/api/context/app`
response by adding a version field to `AppContextResponse` and populating it
from `model.Version` in `appContextHandler`. Keep the existing `/api/version`
route unchanged.

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📥 Commits

Reviewing files that changed from the base of the PR and between 8d99068 and 8e5aa14.

📒 Files selected for processing (2)

• internal/controller/context_controller.go
• internal/controller/context_controller_test.go

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[bsaurusrex]

On the CodeRabbit "Linked Issues" / "Out of Scope" warnings (the issue title mentions /api/context/app):

This intentionally implements the version as a new protected /api/version rather than extending /api/context/app, following your direction in the issue thread:

it would have to be protected, not available to everyone … a public version endpoint gives an attacker an easy way to see if any vulnerabilities are present in that version

Nope, the app context endpoint is public by design to provide the necessary information for the frontend to work for unauthenticated users.

we can do it at the /api/user/context endpoint or we can just add a new protected endpoint for /api/version (I will probably do the second one).

/api/context/app is in contextSkipPathsPrefix (served to unauthenticated clients), so adding the version there would be the public exposure you flagged. /api/version is kept out of the skip list and gated on an authenticated context, which matches "the second one". Happy to switch to /api/user/context instead if you'd prefer that option — just say the word.

The docstring-coverage warning is addressed in the latest commit.