open-telemetry/opentelemetry-collector-contrib v0.163.0

v1.2.0/v0.163.0

on GitHub

The OpenTelemetry Collector Contrib contains everything in the opentelemetry-collector release, be sure to check the release notes there as well.

End User Changelog

🛑 Breaking changes 🛑

• cmd/opampsupervisor: The supervisor now fails to start when the deprecated reports_remote_config capability option is set to true. (#49763)
  Remove reports_remote_config from the supervisor config; accepts_remote_config enables both the AcceptsRemoteConfig and ReportsRemoteConfig OpAMP capabilities. The option will be removed in v0.165.0.

• connector/failover: Reject empty condition.error.contains values and fail over only for matching downstream errors (#44518)
  condition.error.contains now requires a list of non-empty strings.

• exporter/signalfx: Exclude generated container_cpu_utilization metric by default (#51906)
  This metric has been deprecated in favor of container.cpu.usage. If container_cpu_utilization
  is still required, please add it to the exporter's include_metrics configuration option as shown below.

  signalfx:
    include_metrics:
      - metric_name: container_cpu_utilization
  

• extension/google_cloud_logentry_encoding: Fix Cloud DNS query logs failing to decode when vmInstanceId is in exponent notation. host.id is now a string taken from vmInstanceIdString instead of an int taken from vmInstanceId. (#51552)

• processor/redaction: Keep every redaction summary attribute intact when data re-enters the processor (#50770)
  Only five of the fourteen summary attributes the processor writes survived a second redaction processor. When data
  passed through one, redaction.allowed.keys, redaction.allowed.count and the seven redaction.body.* attributes
  were treated as unknown keys, deleted, and reported in redaction.redacted.keys.

  The processor now treats all fourteen as its own bookkeeping rather than as user data, so they are no longer deleted,
  masked, obfuscated or counted as redacted, and the summary accumulates across chained processors as intended.
  Previously a blocked_key_patterns or blocked_values rule matching one of these attributes replaced the summary
  with a masked value, and with redact_all_types enabled it rewrote the *.count integers as strings, which made the
  running totals read back as zero at the next hop.

  Chaining two processors also reported the same attribute more than once: the allowed and ignored summaries
  describe the record as it currently stands, which every processor re-derives in full, so merging them with an
  upstream value counted one attribute twice. redaction.allowed.keys read email,email with
  redaction.allowed.count of 2 for a single allowed attribute. Those two outcomes now replace the upstream
  value, while the redacted and masked outcomes keep accumulating, because a removed key and an already masked
  value cannot be detected again.

  Two behaviour changes come with this, both of which can affect an existing chained configuration.

  A processor whose summary is not debug or info now claims no ownership of a summary it finds, so the ordinary
  allow list decides whether it survives. This lets a strict egress processor strip an upstream audit trail, which it
  could not do before. It also means a downstream processor with allow_all_keys: false now removes the five summary
  attributes it previously kept unconditionally, unless they are named in allowed_keys or allow_all_keys is set.
  summary is unset by default, which counts as silent, so a chained configuration that never sets it is affected.

  A key inside a log body named after a summary attribute is now redacted like any other unknown key. The processor
  only ever writes its summary to the record attributes, so such a key in a body carries user data.

• receiver/postgresql: Set the default scrape timeout to 60s to cancel blocked PostgreSQL queries. (#50757)
  Increase timeout for longer scrapes, or set timeout: 0 to restore the unbounded behavior.

• receiver/prometheus_simple: Remove the long-deprecated tls_enabled and tls_config settings; use tls instead (#51895)
  tls_enabled/tls_config were deprecated in v0.55.0 in favor of the standard
  tls block (confighttp's TLS settings). Besides being long overdue, keeping both
  was a footgun: setting tls_enabled: true silently overrode any tls block.
  Migrate tls_config (ca_file/cert_file/key_file/insecure_skip_verify) to
  the equivalent fields under tls.

• receiver/sql_server: Performance counters read from the SQL Server Databases object on a direct database connection now carry the sqlserver.database.name resource attribute and no longer emit an unlabeled _Total aggregate, which changes the series identity of sqlserver.database.backup_or_restore.rate. (#51384)
  sqlserver.database.backup_or_restore.rate splits from one series into one per database, and the
  unlabeled series it previously reported is gone. Aggregate across sqlserver.database.name instead.
  This brings the direct database connection in line with the Windows performance counter path, which
  already discards the aggregate instance before recording.

🚩 Deprecations 🚩

• receiver/sql_server: Rename the sqlserver receiver to sql_server. The old sqlserver type remains available as a deprecated alias. (#45339)

🚀 New components 🚀

• processor/adaptive_tail_sampling: Promote the adaptive_tail_sampling processor to alpha stability and include it in the contrib distribution. (#49311)
• processor/partitioning: Add the initial skeleton for the partitioning processor. (#39199)
• processor/rolling_span_latency: Promote the rolling_span_latency processor to alpha stability and include it in the contrib distribution. (#50260)

💡 Enhancements 💡

• connector/routing: Validate OTTL conditions and statements during configuration. (#51748)

• connector/service_graph: Recognize current semantic-convention attributes (peer.service.name, db.namespace, db.system.name) alongside legacy keys when deriving peer and database-name dimensions. (#22095)

• exporter/cassandra: Add configuration validation and error case tests. (#51730)

• exporter/clickhouse: Add database_engine config to set the ENGINE used when creating the database, such as Replicated. (#51513)
  When database_engine.name is Replicated, ON CLUSTER is only applied to the CREATE DATABASE statement.

• exporter/datadog: Mark exporter/datadogexporter as unsupported on freebsd/amd64. (#15781)

• exporter/datadog: Move the exporter.datadogexporter.AddUnits feature gate to beta. Metric units are now sent to Datadog by default. (#15280)

• exporter/elasticsearch: Store OTLP exponential histograms in Elasticsearch's native exponential_histogram field (#51429)
  Enabled automatically in OTel mapping mode when connected to Elasticsearch 9.3.0 or later; disable via version_detection.enabled: false.

• exporter/elasticsearch: Log the connected Elasticsearch version and build flavor at startup (#51541)
  Adds version_detection (enabled by default); set version_detection.enabled: false to opt out.

• exporter/kafka: Add the trace context to Kafka record headers using the propagators configured in service::telemetry::traces::propagators. (#51078)

• exporter/nats: Implement core NATS publishing, so traces, metrics, and logs are published to per-signal subjects derived from OTTL value expressions. (#50735)
  JetStream durable publishing is not yet implemented; a configured jetstream block is rejected at startup until it lands.

• exporter/splunk_hec: Define the exporter's heartbeat metrics in metadata.yaml and generate them via mdatagen. (#49009)

• extension/basicauth: Support sourcing credentials from secret provider extensions, with rotation that does not restart the collector. (#48277)
  Configure with htpasswd.secret_provider (server) or client_auth.secret_provider (client).
  The referenced extension must implement the SecretProvider interface (GetSecret and OnChange).

• extension/datadog: Mark extension/datadogextension as unsupported on freebsd/amd64. (#15781)

• extension/opamp: Add a socket option under server.ws and server.http to dial the OpAMP server over a Unix domain socket (transport: unix) or Windows named pipe (transport: npipe). (#50603)
  When socket is set, the endpoint only supplies the URL scheme, request path, and Host
  header; its host and port are ignored.

• extension/pebble_tail_storage: Add on_read_error to choose between dropping a trace or returning the readable part when stored batches cannot be read or decoded. (#49906)
  The default is drop_trace. Take deletes the stored trace and returns an error, and the tail sampling processor drops the trace without a sampling decision.
  Set on_read_error: return_partial to keep the previous best-effort behavior, where Take returns the batches that could still be read.
  Two new metrics, otelcol_extension_pebble_tail_storage_read_error_trace_drops and otelcol_extension_pebble_tail_storage_read_error_partial_returns, count which policy ran.

• internal/kafka: Reuse cached AWS credentials across AWS_MSK_IAM_OAUTHBEARER token generations instead of resolving them on every SASL authentication. (#50038)

• pkg/ottl: Add the pkg.ottl.functions.enableExperimental feature gate, which must be enabled to use experimental OTTL functions. (#51564)

• pkg/ottl: Allow keep_keys to accept slice values from paths and converter expressions when the pkg.ottl.functions.enableDynamicSliceArguments feature gate is enabled. (#45980)

• pkg/ottl: Improve OTTL parse error diagnostics by reporting the line and column of the input where available. (#51680)
  Not all parse errors carry a position: errors that aggregate multiple statements, and some
  inner errors that didn't already carry one, are still returned without one. The exact
  wording and position of statement, condition, and value expression parse error messages
  has changed as a result. The position is exposed programmatically via the new experimental
  xottl.Error type.

• pkg/ottl: Add the beta pkg.ottl.functions.enableDynamicSliceArguments feature gate, which controls whether slice arguments of stable functions such as Concat accept paths and converters. (#51565)

• pkg/stanza: Optimize container parser operator by replacing CRI line and File path regexes with a hand-written parsers and caching log filepath metadata extraction, reducing CPU usage by ~70% on the container parser hot path (#41672)

• pkg/stanza: Add default scope name and version for stanza log entries without scope name (#51084)
  This introduces the pkg.stanza.addDefaultScopeName feature gate (currently in beta) to ensure Stanza log entries are assigned a default scope name and version when not explicitly provided.

• processor/adaptive_tail_sampling: Add fleet_tracker to divide each adaptive_throughput rule's goal_throughput by the live fleet member count reported by a fleet_tracker extension, making the goal a fleet-wide budget instead of a per-instance one. (#50577)

• processor/akamaidetector: Add omit_detector_akamai go build tag to omit detector at build time. (#47218)

• processor/alibabaecsdetector: Add omit_detector_alibaba_ecs go build tag to omit detector at build time. (#47218)

• processor/azuredetector: Add omit_detector_azure go build tag to omit detector at build time. (#47218)

• processor/digitaloceandetector: Add omit_detector_digitalocean go build tag to omit detector at build time. (#47218)

• processor/dynatracedetector: Add omit_detector_dynatrace go build tag to omit detector at build time. (#47218)

• processor/groupbytrace: Allow grouping spans by the service that emitted them within a trace (#50553)
  Adds an emit_strategy option that can be set to service to allow
  emitting spans sourced from a single service within a trace. In some
  setups this may allow spans to move more quickly through the processor
  while still permitting operations such as RED metric generation,
  service discovery, etc. that require spans to be grouped by trace.

• processor/hetznerdetector: Add omit_detector_hetzner go build tag to omit detector at build time. (#47218)

• processor/ibmcloudclassicdetector: Add omit_detector_ibmcloud_classic go build tag to omit detector at build time. (#47218)

• processor/ibmcloudvpcdetector: Add omit_detector_ibmcloud_vpc go build tag to omit detector at build time. (#47218)

• processor/novadetector: Add omit_detector_openstack_nova go build tag to omit detector at build time. (#47218)

• processor/oracleclouddetector: Add omit_detector_oraclecloud go build tag to omit detector at build time. (#47218)

• processor/partitioning: Implement logs partitioning. (#39199)

• processor/partitioning: Implement traces partitioning. (#39199)

• processor/partitioning: Implement metrics partitioning. (#39199)

• processor/resource_detection: Add omit_detector_system go build tag to omit detector at build time. (#47218)

• processor/resource_detection: Add omit_detector_aws_ec2 go build tag to omit detector at build time. (#47218)

• processor/resource_detection: Add omit_detector_env go build tag to omit detector at build time. (#47218)

• processor/resource_detection: Add omit_detector_azure_functions go build tag to omit detector at build time. (#47218)

• processor/resource_detection: Add omit_detector_azure_containerapps go build tag to omit detector at build time. (#47218)

• processor/resource_detection: Add omit_detector_docker go build tag to omit detector at build time. (#47218)

• processor/resource_detection: Add omit_detector_azure_appservice go build tag to omit detector at build time. (#47218)

• processor/resource_detection: Add omit_detector_consul go build tag to omit detector at build time. (#47218)

• processor/resource_detection: Add omit_detector_azure_aks go build tag to omit detector at build time. (#47218)

• processor/resource_detection: Add omit_detector_k8s_api go build tag to omit detector at build time. (#47218)

• processor/resource_detection: Add omit_detector_kubeadm go build tag to omit detector at build time. (#47218)

• processor/resource_detection: Add omit_detector_openshift go build tag to omit detector at build time. (#47218)

• processor/resource_detection: Add omit_detector_aws_lambda go build tag to omit detector at build time. (#47218)

• processor/resource_detection: Add omit_detector_gcp go build tag to omit detector at build time. (#47218)

• processor/resource_detection: Add omit_detector_heroku go build tag to omit detector at build time. (#47218)

• processor/resource_detection: Add omit_detector_aws_eks go build tag to omit detector at build time. (#47218)

• processor/resource_detection: Add omit_detector_aws_elastic_beanstalk go build tag to omit detector at build time. (#47218)

• processor/resource_detection: Add omit_detector_aws_ecs go build tag to omit detector at build time. (#47218)

• processor/scalewaydetector: Add omit_detector_scaleway go build tag to omit detector at build time. (#47218)

• processor/tail_sampling: Move spans out of incoming batches instead of copying them, and declare that the processor mutates data. (#51920)

• processor/tencentcvmdetector: Add omit_detector_tencent_cvm go build tag to omit detector at build time. (#47218)

• processor/upclouddetector: Add omit_detector_upcloud go build tag to omit detector at build time. (#47218)

• processor/vultrdetector: Add omit_detector_vultr go build tag to omit detector at build time. (#47218)

• receiver/aws_cloudwatch: Add scope.name and scope.version to logs and metrics. (#51333)

• receiver/azure_blob: Add a compression option to read gzip compressed blobs (#51412)

• receiver/azure_monitor: Add per-metric time grain overrides for Azure Monitor metric queries. (#51295)

• receiver/google_cloud_spanner: Add missing metrics to top minute transaction stats in googlecloudspannerreceiver. (#51272)

• receiver/google_cloud_spanner: Add top minute split stats metrics and hide_split_stats_keys logic in googlecloudspannerreceiver. All split_stats/top/* metrics gain the split_start and split_limit attributes with PII hiding support. (#51026)

• receiver/google_cloud_spanner: Add query_optimizer_versions and its value_type int_slice logic in googlecloudspannerreceiver. All query_stats/top/* metrics gain this new attribute. (#51219)

• receiver/google_cloud_spanner: Add missing execution metrics to total query stats in googlecloudspannerreceiver. (#51228)

• receiver/google_cloud_spanner: Add total minute transaction stats metrics to googlecloudspannerreceiver. (#51296)

• receiver/kafka: Add partition_processing.max_in_flight.records to run concurrent unmarshal-plus-Consume calls on one independent partition worker. (#51080)
  When max_in_flight.records is above 1, the worker always marks after processing. message_marking.after: false does not mark before Consume.

• receiver/kubelet_stats: Add optional k8s node pid limit and usage metrics. (#48926)
  Adds the following optional metrics to kubeletstatsreceiver:

  • k8s.node.pid.limit
  • k8s.node.pid.usage

• receiver/mongodb: Add assert, global lock queue, and write concern metrics (#51418)
  Adds mongodb.assert.count, mongodb.global_lock.queue.count and
  mongodb.write_concern.wait.time, all disabled by default.

• receiver/mongodb: Add query executor scan and collection scan metrics (#51060)
  Adds mongodb.query_executor.index_key.scanned.count,
  mongodb.query_executor.document.scanned.count and
  mongodb.query_executor.collection_scan.count, all disabled by default.

• receiver/mongodb: Report a loopback server.address as the collector host name, and enable server.port by default (#51633)
  When a scraped node reports a loopback address (localhost, 127.0.0.1 or ::1), server.address now
  reports the host name of the machine running the collector. service.instance.id is seeded from the same
  value and changes for those deployments. server.port was previously disabled by default; disable it with
  resource_attributes.server.port.enabled: false.

• receiver/mysql: Add row-count and database namespace context to the top query event (#51312)

• receiver/oracledb: Add support for Kerberos authentication via a new auth_type option and kerberos configuration block. (#50401)
  Set auth_type: kerberos and configure the kerberos block to authenticate using a keytab,
  credential cache, or password. Kerberos support is implemented in pure Go and requires no external
  libraries.

• receiver/postgresql: Add connect_database to configure which database the receiver connects to for cluster-wide statistics collection. (#50920)

• receiver/prometheus_simple: Restore the stability of the receiver from unmaintained to beta (#11504)

• receiver/prometheus_simple: Validate that endpoint is set and collection_interval is positive, so an invalid configuration is rejected at startup instead of failing later (#11504)

• receiver/pulsar: Add freebsd/amd64 as a supported build platform. (#15781)
  Updated the github.com/AthenZ/athenz dependency to v1.12.27 to enable
  freebsd/amd64 builds.

• receiver/sql_server: Add sqlserver.db.edition resource attribute. (#51414)
  Disabled by default. Opt in by setting resource_attributes.sqlserver.db.edition.enabled: true in the receiver config.

• receiver/windows_event_log: Promote Windows Event Log receiver to beta stability (#42167)

🧰 Bug fixes 🧰

• exporter/awsemf: Drop a metric declaration with an invalid metric_name_selectors regex instead of panicking (#51115)
  An invalid regular expression in metric_name_selectors was passed to regexp.MustCompile,
  panicking during config validation. It is now compiled with regexp.Compile and the error is
  returned, so the declaration is dropped with a warning like an invalid label_matchers regex.

• exporter/datadog: Drop instance from the Azure App Service and Azure Functions running metrics in preparation for more accurate instance descriptions. (#51919)
  otel.datadog_exporter.metrics.running.azureappservices and otel.datadog_exporter.metrics.running.azurefunctions are now tagged only with name, subscription_id, and resource_group, and App Service metrics no longer get an instance tag.

• exporter/file: Fix race condition where a writer could be closed while still in use, causing data to be silently lost. (#49228)
  This will happen in group_by mode when rotation is not set.

• exporter/file: Reject group_by.max_open_files <= 0 and negative rotation values during config validation. (#51515)

• extension/azure_encoding: Do not emit 0-valued timeseries for aggregates (total, count, minimum, maximum, average) that are missing from the source Azure record (#50485)
  Diagnostic settings only export the aggregates a resource supports. A configured
  aggregation whose aggregate is absent from the record is now skipped instead of
  being coerced to 0.

• extension/docker_observer: Discover IPv6-only Docker endpoints and format their port targets correctly. (#50972)

• extension/google_cloud_logentry_encoding: Do not drop log entries with an unparseable trace or spanId, and accept a bare trace ID without the projects/<project>/traces/ prefix. (#51666)
  Unparseable values are kept as the gcp.trace and gcp.span_id log record attributes.

• pkg/faro: Return an error instead of panicking when a log record contains a malformed browser_brand_<N> key (#51759)

• pkg/faro: Skip malformed sdk_integrations entries instead of panicking when translating logs to Faro payloads (#51484)
  An integration entry without a : separator, or a trailing comma, caused the Faro exporter to
  crash the collector. Such entries are now skipped. Versions that contain : are also no longer
  truncated.

• pkg/ottl: Time no longer treats a trailing strptime %Z as Zulu (UTC) when no location is given (#51416)

• pkg/ottl: Reject literal values that are not lists for slice arguments, such as keep_keys(attributes, "http.method") or Concat("a", "-"), at parse time instead of failing on every execution (#51833)

• pkg/stanza: Fix the container parser rejecting containerd logs whose timestamps use a UTC offset instead of Z when format: containerd is set. (#51284)

• processor/adaptive_tail_sampling: Forward an evicted trace on a detached context rather than the context of whichever request triggered the eviction, so its spans are no longer attributed to an unrelated client. (#51691)
  Components reading client.Info downstream, such as headers_setter with from_context, now see no client metadata for an evicted trace instead of the wrong request's.

• processor/adaptive_tail_sampling: Preserve original scope groups, scope metadata, and schema URLs when splitting spans by trace ID, including late spans handled by the decision cache. (#51461)

• processor/cumulative_to_delta: Fix ExponentialBuckets.Diff missing reset when old buckets precede current histogram offset (#51303)

• processor/remotetap: Fix a panic on shutdown (close of nil channel) when a websocket client had already disconnected before the processor shut down. (#51342)

• processor/resource_detection: Honor fail_on_missing_metadata also for the instance identity document and hostname lookups of the ec2 detector (#50826)
  The ec2 detector guarded only its initial instance-id lookup with fail_on_missing_metadata. The
  subsequent instance identity document and hostname lookups always returned their respective errors,
  regardless of the fail_on_missing_metadata setting.

  On clusters where the metadata service implements the EC2-compatible meta-data tree, but not the AWS-specific
  dynamic/instance-identity endpoints, this would lead to a crash on startup even with
  fail_on_missing_metadata: false. The instance-id lookup would succeed and then the identity document lookup would
  fail with HTTP 404. OpenStack Nova based clusters behave this way, so a collector configured with the ec2 detector and
  fail_on_missing_metadata: false failed to start on those hosts rather than skipping the detector.

  The identity document lookup now honors the flag: when fail_on_missing_metadata is false and the endpoint
  responds with HTTP 404, the detector logs at debug level and returns an empty resource. Any other error is still
  returned, since it might be transient. When the flag is true the error is returned as before.

  The hostname lookup honors the flag as well: when fail_on_missing_metadata is false, the detector logs at
  debug level and returns the resource without the host.name attribute, instead of failing the detection or skipping
  the instance tags. When it is true, the error is returned.

• receiver/azure_blob: Return an error instead of panicking when an Event Hub message has no events or an unexpected blob subject (#51474)
  A malformed or unexpected Event Hub message could crash the collector. Such messages are now
  logged as errors and skipped, and events other than blob creation are ignored without being parsed.

• receiver/azure_event_hub: Do not emit 0-valued timeseries for aggregates (total, count, minimum, maximum, average) that are missing from the source Azure record (#50485)
  Diagnostic settings only export the aggregates a resource supports, e.g. a Standard
  Load Balancer exports total and count but no minimum/maximum. Missing aggregates are
  now skipped instead of being coerced to 0.

• receiver/azure_event_hub: Recreate the partition client after an ownershiplost error instead of polling a permanently detached link. (#51463)
  When another receiver with a higher epoch attached to the same partition and consumer group, the
  receiver logged error receiving events on every poll forever and never received data again.
  The partition client is now closed and reopened from the last received sequence number with exponential backoff.

• receiver/cloud_foundry: Do not emit partially initialized log records for unsupported log types. (#51517)

• receiver/googlecloudmonitoring: Emit data points in chronological order to prevent data loss in downstream processors. (#51641)

• receiver/host_metrics: Reject negative metadata_collection_interval values during configuration validation. (#51640)

• receiver/kafka: Fix records from healthy partitions being dropped when a poll also contains a fetch error. (#51852)

• receiver/mysql: Report mysql.index.io.wait.count and mysql.index.io.wait.time under the correct operation attribute (#49597)
  The mysql.index.io.wait.count and mysql.index.io.wait.time metrics were reported under the
  wrong operation attribute (for example, delete counts appeared under operation=update). Each
  datapoint is now reported under its correct operation.

• receiver/postgresql: Add postgresql.userid to db.server.top_query and db.server.query_plan, and key the top-query counter cache and EXPLAIN plan cache on it instead of postgresql.rolname. Fixes a case where two dropped database roles could be reported under each other's counters or query plan, and keeps counter deltas continuous across a role rename. (#51319)

• receiver/prometheus_remote_write: Attach exemplars once, to the series that sent them, rather than to every metric built from the same labels. (#50334, #50546)

• receiver/splunk_enterprise: Fixes recorded value for RollingRestartStatus metric (#51866)

• receiver/sql_server: Fix missing metrics when using direct SQL Server connection - sqlserver.lock.wait_time.avg, sqlserver.transaction.rate, sqlserver.page.operation.rate, sqlserver.page.lazy_write.rate, and sqlserver.transaction_log.growth.count now emit values on non-Windows platforms and when the receiver is configured with a direct database connection. (#51384)
  All of these except sqlserver.transaction_log.growth.count report no
  data point on the first scrape, since they are calculated from the change in their counters between scrapes.

• receiver/sql_server: sqlserver.session.duration now reports whole seconds since login instead of milliseconds, fixing a 25-day overflow in total_elapsed_time. (#51419)

• receiver/sql_server: Fix direct connection queries returning no data when instance_name is set to a named instance (#50773)
  The direct connection queries filtered rows with @@SERVERNAME = '<instance_name>'. On a named
  instance @@SERVERNAME returns <host>\<instance>, which never matches the bare instance name,
  so every query returned zero rows and no metrics were emitted. The filter was also redundant:
  a connection is scoped to a single instance and its DMVs only expose that instance. It has been
  removed. instance_name remains in use for the Windows performance counter collection path.

• receiver/sql_server: Fix direct-connection performance counter rate metrics to emit per-second rates instead of cumulative counter values. (#50772)
  The sqlserver.page.buffer_cache.free_list.stalls.rate metric value type changes from int to double so fractional rates can be represented.

• receiver/statsd: Close the TCP connection when the client disconnects and bound the size of an unterminated line, fixing a per-connection file descriptor leak and an unbounded memory growth path in the TCP transport. (#50123)

• receiver/webhook_event: Validate that path and health_path begin with a leading / so the collector fails at config load instead of panicking at startup. (#50893)
  A path or health_path without a leading / caused httprouter to panic in Start(),
  after the collector had already bound its telemetry port. The panic left the port held, so every
  restart attempt failed with bind: address already in use.

• receiver/yang_grpc: Apply the configured security.allowed_clients and security.rate_limiting settings to the MdtDialout streaming RPC, which previously did not enforce either. (#0)

• scraper/network: Fix incorrect Linux TCP state names (FIN_WAIT_1/FIN_WAIT_2) used by the networkscraper, which never matched real connection states. (#51271)

API Changelog

🛑 Breaking changes 🛑

• pkg/ottl: FunctionContext and the Standard*Getter structs can no longer be initialized with unkeyed struct literals. (#47305)

• pkg/ottl: Move the experimental lambda expression Go API into the pkg/ottl/xottl module so it is excluded from OTTL's stability guarantees. (#51566)
  LambdaExpression, LambdaActivation, and NewTestingLambdaExpression moved to
  github.com/open-telemetry/opentelemetry-collector-contrib/pkg/ottl/xottl. LocalIdentifierDecl and
  LambdaExpression.Formals were removed.

• pkg/ottl: Move the experimental SliceGetter API to the xottl module. (#51565)
  ottl.SliceGetter, ottl.GetLiteralValues, ottl.GetScalarLiteralValues, and ottl.NewTestingSliceGetter are now in xottl.

💡 Enhancements 💡

• connector/routing: Create With*Functions factory options to allow custom OTTL functions registration. (#51709)

• pkg/ottl: Improve OTTL parse error diagnostics by reporting the line and column of the input where available. (#51680)
  Not all parse errors carry a position: errors that aggregate multiple statements, and some
  inner errors that didn't already carry one, are still returned without one. The exact
  wording and position of statement, condition, and value expression parse error messages
  has changed as a result. The position is exposed programmatically via the new experimental
  xottl.Error type.

• pkg/ottl: Add WithCache option to the ottlotelcol TransformContext. (#51652)

• pkg/pdatatest: Add pmetricassert numeric comparison operators (#48470)

🧰 Bug fixes 🧰

• pkg/ottl: Preserve the distinction between nil and empty slices in the xottl GetScalarLiteralValues and GetLiteralValues helpers. (#51814)

We are thrilled to welcome our first-time contributors to this project. Thank you for your contributions @uttam282005, @anarwal, @bvetsa, @MartinCajiao, @Syedowais312, @Bbn08, @SatoshiKamiyama, @Harshal96, @IsharaEkanayaka, @hpaliwal8, @meebok, @gowchin, @cauebraz, @svencowart, @RutamBhagat, @hajimeCha, @TeodorDichev, @rluidash, @stackempty, @zanarellidev, @kth496, @kalaivani9721, @abhishekjoshi2612, @jstar0, @JashRashne ! 🎉