Histograms recorded inside a sampled span carry trace IDs automatically, so a
latency spike links to a trace that caused it. Nothing said so.
Two things are documented because they were measured rather than assumed: an
exemplar is kept per histogram bucket, so the bucket boundaries fixed earlier
in this stack took the same workload from one reachable trace to four; and the
pinned opentelemetry-exporter-prometheus drops exemplars entirely, so the path
that works is an OTLP collector rather than Datasette's Prometheus exporter.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
(cherry picked from 9d066255; section numbering and cross-references
adjusted to this branch's demo README, and the exemplar reference placed
as a subsection of the new Metric reference in internals.rst.)
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01F2h9ANGZ7paWSpqs5DUAcG
Both histograms declared unit="s" but inherited OpenTelemetry's default
boundaries, which are tuned for milliseconds - so every SQLite query
landed in the single (0, 5] second bucket and every quantile query
returned noise.
The boundaries are the semantic conventions' recommended set for
db.client.operation.duration plus 0.0001 and 0.0005 at the bottom, since
SQLite is in-process and many real queries take tens of microseconds.
(Adapted from 024f2029: that commit assumed the metrics were already in
telemetry_registry.py, which on this lineage held spans only - so this
commit also brings the MetricName registry machinery, the registry
entries for all eight phase-3 metrics, the cog-generated Metric
reference in internals.rst, and the datasette.operation attribute. The
template and facet histograms it also touched belong to phase 5 and are
not included.)
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01F2h9ANGZ7paWSpqs5DUAcG
Response.error(messages, status=400) builds a JSON error response in
Datasette's standard error format, alongside Response.json/html/text.
messages can be a single string or a list. All internal error response
construction now uses it - the private views.base._error() helper is
gone and the verbose Response.json(error_body(...), status=...) sites
are converted. error_body() remains for the cases that merge the error
keys into a larger payload (the JSON renderer, handle_exception and the
permission debug payload builders).
Since Response is public plugin API, plugins that build JSON endpoints
now have an obvious way to return errors in the canonical shape.
Documented in the internals documentation, including the guidance to
raise Forbidden/NotFound/BadRequest/DatasetteError instead when the
error should content-negotiate.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01GrHZSypDfMnym1tM5XJAFZ
Adds a per-request cache for permission check results, plus wiring that
resolves action permissions in bulk before plugin hooks need them:
- New _permission_check_cache contextvar, set to a fresh dict for each
request by DatasetteRouter and reset when the request ends. Keys
include the full serialized actor, so actors differing in any field
(e.g. token restrictions) never share entries. SkipPermissions mode
bypasses the cache entirely.
- datasette.allowed_many() now consults the cache and stores its
results there, so repeated datasette.allowed() checks within one
request resolve without further SQL.
- Table pages resolve all registered table-level actions against the
current table and all database-level actions against its database
(database pages likewise) in batched queries before invoking the
table_actions/database_actions plugin hooks - allowed() calls made
inside those hooks are then served from the cache with no plugin
changes required. Actions with no permission rules from any plugin
are resolved to False without touching the database.
Benchmarks (benchmarks/) with a simulated 12-plugin ecosystem making
18 checks per table page show 34 -> 13 internal-DB queries per page;
with 2ms-per-query internal DB latency (modelling Datasette Cloud)
table page time drops from 77.9ms to 27.6ms - the caching layer
accounts for ~91% of that improvement over allowed_many() alone.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
* Fix for execute write returning, closes#2762
* Fix stored write returning rowcount message
* Add configurable execute_write returning limit
* Return rows/truncated from execute query if it used RETURNING
* INSERT ... RETURNING shows rows in /-/execute-write
* Skip RETURNING tests if SQLite version does not support it
Screenshot: https://github.com/simonw/datasette/issues/2762#issuecomment-4588111545
Datasette.close() iterates over every attached Database (including the
internal database), calls Database.close() on each, then shuts down the
ThreadPoolExecutor. Exceptions raised by one Database don't prevent the
others from being closed; the first exception is re-raised afterwards.
Idempotent.
Refs #2692
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
After this commit, Database.close() sends a sentinel to the write queue so
the background write thread exits cleanly, closes cached read/write
connections, and marks the instance closed. Subsequent calls to execute*()
raise DatasetteClosedError. close() remains idempotent and one-way.
Refs #2692
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
`datasette.client.get(path, actor={"id": "root"}` now makes the internal request with that actor as `request.actor` - same for the other HTTP verb methods on `datasette.client`.
Upgraded relevant tests to use the new `actor=` mechanism.
- New CSRF protection middleware inspired by Go 1.25 and research by Filippo Valsorda - https://words.filippo.io/csrf/ - this replaces the old CSRF token based protection.
- Removes all instances of `<input type="hidden" name="csrftoken" value="{{ csrftoken() }}">` in the templates - they are no longer needed.
- Removes the `def skip_csrf(datasette, scope):` plugin hook defined in `datasette/hookspecs.py` and its documentation and tests.
- Updated CSRF protection documentation to describe the new approach.
- Upgrade guide now describes the CSRF change.
Closes#2683
* Add is_temp_disk option to Database for temp file-backed databases
Replace the default in-memory internal database with a temporary
file-backed database using WAL mode. This fixes concurrent read/write
locking errors that occur with named in-memory SQLite databases.
The new is_temp_disk parameter on Database creates a temp file via
tempfile.mkstemp, connects to it as a regular file-based database
with WAL mode enabled, and cleans it up on close() and via atexit.
https://claude.ai/code/session_01TteLrUjpDcARjnP1GMRqz2
I noticed that VACUUM can update the rootpage for tables in a way that
could confuse our rename table detection logic - but using the
execute_isolated_fn() method to run VACUUM avoids this problem.
Refs #2681
* Add track_event callback to execute_write_fn and write_wrapper
Allows write functions and write_wrapper generators to queue events
during a write operation that are dispatched after successful commit.
The fn or wrapper can optionally accept a `track_event` parameter
(detected via call_with_supported_arguments). Events are discarded
if the write raises an exception.
Does not yet handle the block=False (non-blocking) case - events
queued during non-blocking writes are currently silently discarded.
Refs https://github.com/simonw/datasette/issues/2681
* Dispatch track_event events for non-blocking (block=False) writes
Spawns a background asyncio task that awaits the write thread's reply
queue and dispatches pending events after a successful non-blocking
write. Events are still discarded if the write raises an exception.
Refs https://github.com/simonw/datasette/issues/2681
* Warn that events won't fire for other processes
Refs https://github.com/simonw/datasette/issues/2681#issuecomment-4157118662
* Document call_with_supported_arguments as a supported public API
Mark both call_with_supported_arguments and async_call_with_supported_arguments
with the @documented decorator and add documentation to docs/internals.rst
so plugin authors can use these dependency injection utilities in their own code.
https://claude.ai/code/session_01DKogZpHwzCTrbeG4XjXmNc
- register_column_types() now returns classes instead of instances
- ColumnType.__init__ takes optional config=, baking it into the instance
- get_column_type() returns a ColumnType instance (or None) instead of a
(name, config) tuple
- get_column_types() returns {col: ColumnType instance} instead of tuples
- Remove get_column_type_class() - no longer needed
- render_cell/validate/transform_value methods no longer take config arg;
use self.config instead
- render_cell hook takes column_type (ColumnType or None) instead of
column_type + column_type_config
https://claude.ai/code/session_01SvPEPqHgURTWESRp28pTC3
