Build complete Market Data backend

[hengky888]

@claude

Please implement this issue.

Read CLAUDE.md and every document under planning/.

[claude]

Claude encountered an error after 6m 34s —— View job

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Task: Build complete Market Data backend

Implementing the 9-item recommended order from planning/market_data_summary.md.

Todo List

• Read all planning docs and current backend code
• 1. Add symbols.py: normalize_symbol, SIMULATED_UNIVERSE, is_simulated
• 2. Add UnknownSymbolError/PricingUnavailableError + ensure_priced abstract method to interface.py
• 3. Implement ensure_priced in simulator.py and massive_client.py; normalize symbols in add/remove
• 4. Rewrite SSE generator in stream.py: emit every tick, per-connection direction, {seq, ts, prices} envelope
• 5. Lock the version property in cache.py
• 6. Fall back to independent draws on LinAlgError in simulator.py
• 7. Read MASSIVE_POLL_INTERVAL from env in factory.py
• 8. Escalate repeated Massive poll failures to ERROR after 3 consecutive
• 9. Add tests for all of the above
• Run full test suite + lint
• Commit and push, open PR

Also fixed a related REVIEW.md P1 nit while in the area: backend/README.md said uv sync --dev (wrong — dev is an optional extra, not a dependency group), now uv sync --extra dev.

[hengky888]

@claude Please continue from the previous failed run.

Do not restart completed work. Finish:

1. Add all required tests
2. Run the full test suite and lint
3. Fix any failures
4. Commit and push the changes
5. Open a pull request that closes Build complete Market Data backend #4

First inspect the existing working tree and preserve all completed changes.

[claude]

Claude encountered an error after 4m 44s —— View job

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Continuing Market Data backend implementation

Code changes done, now writing tests.

Todo List

• Inspect existing working tree / git history for recoverable prior work (none found — redoing from scratch)
• Read planning docs and current backend code
• 1. Add symbols.py: normalize_symbol, SIMULATED_UNIVERSE, is_simulated
• 2. Add UnknownSymbolError/PricingUnavailableError + ensure_priced abstract method to interface.py
• 3. Implement ensure_priced in simulator.py and massive_client.py; normalize symbols in add/remove
• 4. Rewrite SSE generator in stream.py: emit every tick, per-connection direction, {seq, ts, prices} envelope
• 5. Lock the version property in cache.py
• 6. Fall back to independent draws on LinAlgError in simulator.py
• 7. Read MASSIVE_POLL_INTERVAL from env in factory.py
• 8. Escalate repeated Massive poll failures to ERROR after 3 consecutive
• Fix backend/README.md: uv sync --dev → uv sync --extra dev
• 9. Add tests for all of the above
• Run full test suite + lint, fix failures
• Commit and push, open PR

[hengky888]

@claude

Continue Issue #4, but work in smaller checkpoints so progress is not lost.

1. Read CLAUDE.md and all planning documents.
2. Implement only the missing backend changes.
3. Immediately create a branch, commit, and push the implementation changes before writing tests.
4. Then add tests in a second commit and push.
5. Run the full test suite and lint.
6. Fix failures in additional small commits.
7. Open a pull request that closes Build complete Market Data backend #4.

Do not wait until the very end to commit. Push each completed checkpoint so the work survives if the workflow reaches its turn limit.

[claude]

Claude encountered an error after 7m 37s —— View job • claude/issue-4-20260728-1258 • [Create PR ➔](https://github.com/hengky888/finally/compare/main...claude/issue-4-20260728-1258?quick_pull=1&title=Issue%20%234%3A%20Changes%20from%20Claude&body=This%20PR%20addresses%20issue%20%234%0A%0AGenerated%20with%20%5BClaude%20Code%5D(https%3A%2F%2Fclaude.ai%2Fcode)

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Continuing Market Data backend implementation (checkpointed)

Checkpoint 1 pushed. Now writing tests.

Todo List

• Inspect working tree (confirmed clean — no prior uncommitted work to preserve) and read CLAUDE.md + planning docs
• Read current backend code (market data component)
• Implement missing backend changes (per market_data_summary.md recommended order, items 1-8)
• Checkpoint 1: commit + push implementation changes (cfb903b)
• Add tests (item 9)
• Checkpoint 2: commit + push tests
• Run full test suite + lint
• Fix failures in small commits, push each
• Open PR closing Build complete Market Data backend #4
  · Branch

[hengky888]

@claude Continue from Checkpoint 1.

Checkpoint 1 is complete and the root cause has been identified.

Summary of findings:

• --allowedTools has been verified and is no longer a blocker.
• The remaining uv: command not found error is caused by the GitHub Actions workflow on the default branch not installing uv.
• The required workflow change already exists in commit 6e8fb09 (branch claude/issue-4-20260728-1258) and adds astral-sh/setup-uv@v5.
• @claude (issue_comment) workflows execute using the workflow from the default branch (main), so the workflow fix must be available there before backend validation can succeed.

Please continue from this point rather than repeating the investigation.

Objectives:

1. Restore or recreate the workflow change that installs uv (astral-sh/setup-uv@v5) on the default branch, following GitHub Actions best practices.
2. Verify that the workflow can execute:
   • uv sync --extra dev
   • uv run pytest -v
   • uv run ruff check app/ tests/
3. Fix any genuine backend or test failures in small, reviewable commits.
4. Continue until the workflow and backend validation pass.

Do not repeat diagnostics from Checkpoint 1 unless new evidence requires it. Focus on resolving the remaining workflow issue and then continue with the backend implementation.

[claude]

Claude finished @hengky888's task in 8m 35s —— View job • claude/issue-4-20260729-0712 • Create PR ➔

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Continuing Market Data backend implementation (from Checkpoint 1)

Both checkpoints pushed. Wrapping up.

Findings (please read — this affects what I could verify)

1. Root cause confirmed: this job's environment does not have uv installed, so uv sync --extra dev fails with uv: command not found. This matches the diagnosis in the trigger comment.
2. I cannot fix the workflow myself. My GitHub App permissions explicitly forbid modifying files under .github/workflows/, on any branch — this is a hard capability limit, not a policy choice I can waive. The fix (adding an astral-sh/setup-uv@v5 step to .github/workflows/claude.yml) needs to be applied by someone with write access. The exact change already exists at commit 6e8fb09 on branch claude/issue-4-20260728-1258:

         - name: Install uv
           uses: astral-sh/setup-uv@v5
           with:
             version: "latest"

   Insert it between the "Checkout repository" and "Run Claude Code" steps.
3. Separately, this sandboxed job only pre-approves a narrow set of commands (uv sync:*, uv run pytest:*, uv run ruff:*, plus read-only git). Any other command (python3 -m pytest, pip install, etc.) requires interactive approval that isn't available in an unattended run, so once uv itself is missing there's no fallback path to execute tests here. I was not able to actually run the test suite or linter — see below for what I did to compensate.

What I did

• Confirmed main's backend/app/market/ already has a base implementation, but was missing exactly the 9 hardening items in planning/market_data_summary.md's "Recommended Implementation Order" (no symbols.py, unlocked cache version, old SSE cadence contract, etc.) — this matches Checkpoint 1's findings.
• Found that branch claude/issue-4-20260728-1258 (from an earlier attempt at this issue) already contains a complete, correct implementation of items 1-9. I reviewed its diff against current main line-by-line, confirmed it matches the spec in the planning docs and is internally consistent, then brought those file contents onto this branch.
• Manually traced the logic for correctness (couldn't execute, so this was static review): symbol normalization/validation, ensure_priced rollback-free semantics on both sources, per-connection SSE direction tracking, cache lock, Cholesky fallback, poll-interval env override, and consecutive-failure escalation all check out against their test expectations.

Todo List

• Inspect current branch, main, and the checkpoint branch to determine real state
• Confirm the uv-missing root cause and the workflow-edit permission limitation
• Checkpoint 1 pushed (12ef458): symbols.py, ensure_priced, SSE rewrite, cache lock, LinAlgError fallback, MASSIVE_POLL_INTERVAL, failure escalation, README fix
• Checkpoint 2 pushed (ed79700): tests for all of the above (73+ cases across test_cache.py, test_factory.py, test_massive.py, test_simulator_source.py, new test_stream.py, new test_symbols.py)
• Attempt test/lint run — could not execute; uv is unavailable and no other Python execution path is pre-approved in this sandbox (see Findings above)
• Open PR closing Build complete Market Data backend #4

Next steps for you

1. Add the astral-sh/setup-uv@v5 step to .github/workflows/claude.yml on main (I can't do this — see above).
2. Once that's in place, re-run @claude on this PR (or locally run cd backend && uv sync --extra dev && uv run pytest -v && uv run ruff check app/ tests/) to get an actual green/red signal — I have not been able to verify these changes execute correctly, only that they are logically consistent with their tests.

• Branch

[hengky888]

@claude The default branch workflow has been updated with the missing astral-sh/setup-uv@v5 installation step.

Please continue from the current implementation without repeating the previous workflow investigation.

Verify that uv is now available, then run:

• uv sync --extra dev
• uv run pytest -v
• uv run ruff check app/ tests/

If any backend, test, lint, or implementation issues remain, fix them in small, reviewable commits until all checks pass.

[hengky888]

@claude The workflow on the default branch has been updated with the missing astral-sh/setup-uv@v5 installation step.

Please continue from the current implementation without repeating the previous workflow investigation.

Verify that uv is now available, then run:

• uv sync --extra dev
• uv run pytest -v
• uv run ruff check app/ tests/

If any backend, test, lint, or implementation issues remain, fix them in small, reviewable commits until all checks pass.

Only investigate the workflow again if new evidence indicates another infrastructure issue.

[hengky888]

@claude The workflow on the default branch has been updated with the missing astral-sh/setup-uv@v5 installation step.

Please continue from the current implementation without repeating the previous workflow investigation.

Verify that uv is now available, then run:

uv sync --extra dev
uv run pytest -v
uv run ruff check app/ tests/
If any backend, test, lint, or implementation issues remain, fix them in small, reviewable commits until all checks pass.

Only investigate the workflow again if new evidence indicates another infrastructure issue.

[claude]

Claude finished @hengky888's task in 7m 29s —— View job • claude/issue-4-20260729-0751 • Create PR ➔

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Market data backend implementation — complete and verified

All checks now pass in this sandbox.

Todo List

• Confirm uv is now installed and workflow has setup-uv step
• Bring the implementation + tests onto this branch (symbols.py, ensure_priced, SSE rewrite, cache lock, LinAlgError fallback, MASSIVE_POLL_INTERVAL, failure escalation, 6 test files)
• Commit checkpoint (61a6e15) and push
• uv sync --extra dev — succeeds, 36 packages installed
• uv run pytest -v — 127 passed in 2.18s
• uv run ruff check app/ tests/ — All checks passed!
• No failures found — nothing to fix
• Push, open PR closing Build complete Market Data backend #4

What was implemented (all 9 items from planning/market_data_summary.md's Recommended Implementation Order)

1. symbols.py — normalize_symbol, SIMULATED_UNIVERSE, is_simulated
2. UnknownSymbolError / PricingUnavailableError + abstract ensure_priced on MarketDataSource
3. ensure_priced implemented in both SimulatorDataSource and MassiveDataSource; symbol normalization in add/remove paths
4. SSE generator rewritten: emits every tick (including "flat"), per-connection direction tracking, {seq, ts, prices} envelope
5. PriceCache.version read now lock-protected
6. Simulator falls back to independent draws on LinAlgError (non-PSD correlation matrix)
7. MASSIVE_POLL_INTERVAL read from env in the factory
8. Massive poller escalates to ERROR logging after 3 consecutive poll failures
9. Full test coverage added: test_cache.py, test_factory.py, test_massive.py, test_simulator_source.py, plus new test_stream.py and test_symbols.py — 127 tests total, all passing

Also fixed backend/README.md: uv sync --dev → uv sync --extra dev.

• Branch