fix(deploy): use server group's last_revision for incremental deploys

[facundofarias]

Summary

• dhq deploy -s "Group Name" always did a fresh full deploy from the first commit, ignoring the group's prior deployment history.
• Root cause: when -s resolved to a server group, resolvedServer was set to nil and the group was never captured, so resolveStartRevision returned "" — which the API interprets as "deploy entire branch from the first commit".
• Fix: capture resolvedGroup *sdk.ServerGroup alongside resolvedServer for both name- and UUID-based group resolution, and use ServerGroup.LastRevision / ServerGroup.PreferredBranch when no server is resolved. Matches the Rails-side ServerGroup#last_revision semantics (end_revision of the most recent group-targeted deployment).
• Newly-created groups still fall through to a full deploy because their LastRevision is empty — preserving the expected first-deploy behaviour.

Reported by

Customer follow-up to #11 / DHQ-586: name resolution now works, but the resulting deploy ignores the previous commit and starts fresh.

Test plan

• go vet ./... clean
• golangci-lint run ./... — 0 issues
• go test ./... — full suite passes
• 6 new unit tests cover the group paths:
  • TestResolveStartRevision_GroupLastRevisionUsedWhenNoServer
  • TestResolveStartRevision_GroupIgnoredWhenServerHasLastRevision
  • TestResolveStartRevision_FreshGroupReturnsEmpty
  • TestResolveStartRevision_FullClearsGroupLastRevision
  • TestResolveBranchAndRevision_UsesGroupPreferredBranch
  • TestResolveBranchAndRevision_FetchesGroupWhenServerFails
  • TestResolveBranchAndRevision_ServerPreferredBranchBeatsGroup
• Manual smoke against staging: dhq deploy -p <project> -s "<group name>" — verify the new deployment's start_revision matches the group's previous end_revision.

🤖 Generated with Claude Code

Summary by CodeRabbit

• New Features
  • Deployment now properly recognizes and targets server groups as well as individual servers, improving branch selection during deploys.
• Bug Fixes
  • Incremental deployment baseline logic corrected for group deployments so start revisions are chosen correctly, avoiding unnecessary full deployments.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

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Run ID: 96ad839e-86ed-460a-a247-1421b0967abf

📥 Commits

Reviewing files that changed from the base of the PR and between 04a4555 and 2a509c6.

📒 Files selected for processing (1)

• internal/commands/deploy_test.go

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

• internal/commands/deploy_test.go

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Walkthrough

Deploy command extended to support both Server and ServerGroup targets. Branch and start-revision resolution functions now accept pre-resolved groups. Command flow tracks and resolves group identifiers, fetching missing data eagerly. Test infrastructure and coverage updated to validate group-aware branch selection, incremental baselines, and resolution precedence.

Changes

Server group deployment support

Layer / File(s)	Summary
Branch and start-revision resolution logic internal/commands/deploy.go	resolveBranchAndRevision accepts a pre-resolved ServerGroup and falls back to group PreferredBranch or Branch when available. resolveStartRevision accepts a group parameter and returns group.LastRevision when available for incremental deployments. Updated documentation clarifies the fallback chain for branch selection.
Deploy command flow refactoring internal/commands/deploy.go	Deploy command tracks both resolvedServer and resolvedGroup variables. During target name resolution, group-matching path sets resolvedGroup, clears resolvedServer, and updates the server identifier. Eager-fetch populates either resolvedServer or resolvedGroup based on what resolves. Both resolved values flow into branch/start-revision resolution and StartRevision computation.
Test infrastructure and signature updates internal/commands/deploy_test.go	Test mux extended with server-group endpoint mappings and GET /server_groups/:id route handler. All existing resolveBranchAndRevision test calls updated to pass the new knownGroup parameter (set to nil for server-only paths).
Test coverage for server-group resolution and incremental behavior internal/commands/deploy_test.go	New and updated tests for resolveStartRevision validate nil-target behavior, group LastRevision baseline usage, --full and --start-revision override precedence, and server LastRevision fallback. Branch resolution tests extended to cover group preferred_branch honoring, group fetch after server 404, and precedence when both server and group preferred branches are present.

Possibly related PRs

• deployhq/deployhq-cli#11: Both PRs modify deploy target resolution to correctly handle server-group inputs; this PR extends resolution to track both server and group separately and uses both for branch/start-revision selection.

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🎯 3 (Moderate) | ⏱️ ~25 minutes

🚥 Pre-merge checks | ✅ 4

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately summarizes the main change: enabling server group's last_revision for incremental deploys, which directly addresses the root cause described in the PR objectives.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch fix/deploy-group-incremental

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[coderabbitai]

🧹 Nitpick comments (1)

internal/commands/deploy_test.go (1)

429-454: ⚡ Quick win

Consider adding branchesCalled assertion for consistency.

The equivalent server test (TestResolveBranchAndRevision_UsesServerPreferredBranch at line 118) explicitly verifies branchesCalled is true. Adding the same assertion here would improve test explicitness and pattern consistency.

Proposed assertion to add

After line 453, add:

 	assert.Equal(t, "sha-of-release", revision, "must be release's tip, not main's")
+	assert.True(t, mux.branchesCalled, "should query /branches to map branch→sha")
 	assert.False(t, mux.latestRevCalled, "should NOT fall back to repo default")

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@internal/commands/deploy_test.go` around lines 429 - 454, Add an assertion to
verify the branches endpoint was called by asserting the branchEndpointMux
instance's branchesCalled flag is true; in
TestResolveBranchAndRevision_UsesGroupPreferredBranch (where mux is the
branchEndpointMux) add something like assert.True(t, mux.branchesCalled, "should
call branches endpoint") just before or after the existing latestRevCalled
assertion to match the pattern used in
TestResolveBranchAndRevision_UsesServerPreferredBranch.

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Nitpick comments:
In `@internal/commands/deploy_test.go`:
- Around line 429-454: Add an assertion to verify the branches endpoint was
called by asserting the branchEndpointMux instance's branchesCalled flag is
true; in TestResolveBranchAndRevision_UsesGroupPreferredBranch (where mux is the
branchEndpointMux) add something like assert.True(t, mux.branchesCalled, "should
call branches endpoint") just before or after the existing latestRevCalled
assertion to match the pattern used in
TestResolveBranchAndRevision_UsesServerPreferredBranch.

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: 1ecc05ff-df65-4711-9958-37df4d53d6b5

📥 Commits

Reviewing files that changed from the base of the PR and between c5cb8e5 and 04a4555.

📒 Files selected for processing (2)

• internal/commands/deploy.go
• internal/commands/deploy_test.go