feat: add FastMcpBootstrapper#105
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Design captured for replacing InstrumentNotReadyWarning with a pre- instantiation `is_configured` classmethod check + structured skipped_instruments introspection + single INFO summary log. The current post-PR-#86 behavior fires a warning every time an instrument's is_ready() returns False — typically a user-config opt-out, not an anomaly. Every service that uses a subset of available instruments emits multiple warnings on bootstrap; tests can't suppress without breaking the warning assertions. The redesign moves the config check before check_dependencies, makes it a classmethod (preserves PR #88's no-instantiation-on-missing-dep constraint), and removes the warning entirely. dep-missing still warns (genuine deployment surprise). Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
The original design aimed to wrap FastMCP.lifespan with combine_lifespans to wire teardown automatically. Implementation surfaced that FastMCP.lifespan is a read-only bound method on AggregateProvider and the runtime hook is the private _lifespan attribute (set at constructor time only). The spec's documented fallback — "teardown is manual" — is now the adopted approach. Updates: - Spec: §"Teardown wiring risk" → §"Teardown is manual"; tests list drops ASGI-lifespan and user-lifespan-preserve tests, adds test_fastmcp_teardown_resets_is_bootstrapped. - Plan: Task 4 module skeleton no longer mutates lifespan; Task 5 reduced to single teardown-reset assertion; integrations page documents how users wire teardown themselves. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
…eadyError Final-review followup: assert on the project's typed exception rather than bare RuntimeError so a future change to the base class hierarchy doesn't silently weaken the test. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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Earlier work concluded teardown had to be manual because FastMCP.lifespan is a read-only bound method. Re-investigation surfaced FastMCP.add_provider, which DOES accept post-construction providers and invokes each provider's lifespan async context manager during ASGI startup/shutdown. A small _TeardownProvider(Provider) wraps bootstrapper.teardown() and is registered automatically from FastMcpBootstrapper.__init__. Users no longer need to call teardown() manually — it runs when the ASGI application that serves application.http_app() shuts down. Restores test_fastmcp_teardown_runs_via_asgi_lifespan with a hand-rolled ASGI lifespan driver. Drops the "manual teardown" section from the integrations doc. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Matches the fastapi-all / litestar-all / faststream-all naming pattern. fastmcp-all = [lite-bootstrap[fastmcp,fastmcp-metrics,sentry,logging,pyroscope]], so users can install the whole stack with a single extra rather than composing five extras by hand. Updates docs/introduction/installation.md to list `fastmcp-all` in the "all" row and drops the now-obsolete "no rollup" note above the table. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
A recent faststream release tightened AsgiFastStream's typed signature to BrokerUsecase (no None). The wo_broker test path passed broker=None positionally, which started failing CI with both a ty error and a runtime AttributeError on _update_fd_config. build_faststream_config now omits the broker argument entirely when no broker is provided. test_faststream_bootstrap_health_check_wo_broker keeps its semantics (verifying the brokerless health-check path). Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
…ngInstrument LoggingInstrument.check_dependencies (the parent) already returns is_structlog_installed, and BaseBootstrapper._register_or_skip filters the instrument out before instantiation when it returns False. Reaching FastMcpLoggingInstrument.bootstrap() therefore implies structlog is installed; the inner guard is unreachable defensive code. Surfaced by codecov flagging it as uncovered on PR #105. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
… _TeardownProvider Three of the spec/plan sections still described the short-lived "manual teardown" fallback that was reverted in commit b786781. Specifically: - spec §"Teardown is manual" → §"Teardown via Provider.lifespan" - spec Tests list: restore test_fastmcp_teardown_runs_via_asgi_lifespan - plan locked-decisions: replace "Teardown: manual" with the add_provider wiring; mention fastmcp-all rollup - plan Task 5: explain the direct + lifespan test pair Also adds a one-line comment to _TeardownProvider explaining that FastMCP exposes no on_shutdown-style API and Provider.lifespan is the only public post-construction hook. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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Summary
FastMcpBootstrapperandFastMcpConfigthat wire the lite-bootstrap instrument stack (Sentry, Pyroscope, structlog logging with an MCP protocol-level access-log middleware, JSON health endpoint, Prometheus metrics endpoint) onto a user-suppliedFastMCPinstance.import_checker,instruments_typesClassVar registry, and single-file bootstrapper module mirroringfaststream_bootstrapper.py.fastmcp(depends onfastmcp),fastmcp-metrics(addsprometheus-client>=0.20), andfastmcp-allrollup (parity withfastapi-all/litestar-all/faststream-all).Provider.lifespanhook. The bootstrapper registers an internal_TeardownProviderfrom its__init__, and the provider'slifespanasync-cm runsbootstrapper.teardown()on ASGI shutdown.FastMCP.lifespanitself is a read-only bound method (the real hook is_lifespan, captured at constructor time only), soadd_provideris the only public post-construction lifecycle hook — that's what we use. Users don't need to callteardown()themselves.Spec:
docs/superpowers/specs/2026-06-01-fastmcp-bootstrapper-design.mdPlan:
docs/superpowers/plans/2026-06-01-fastmcp-bootstrapper.mdTest plan
just test— full suite passes (19 new fastmcp tests + 129 existing)just lint— clean (ruff, eof-fixer, ty)lite_bootstrap/bootstrappers/fastmcp_bootstrapper.pyis 100% via 19 dedicated tests (health route, prometheus route, MCP middleware logging, teardown via direct call and via ASGI lifespan, missing-dependency regression for sentry/structlog/prometheus_client, not-ready when fastmcp is absent)lite-bootstrap[fastmcp-all]in a scratch project, boot aFastMCPapp, hit/health/and/metrics, shut down via ASGI lifespan and confirm teardown runsprometheus-client/ withoutstructlog; confirmUserWarning+ clean boot🤖 Generated with Claude Code