v0.125.0

This Splunk OpenTelemetry Collector release includes changes from the opentelemetry-collector v0.125.0
and the opentelemetry-collector-contrib v0.125.0 releases where appropriate.

🛑 Breaking changes 🛑

• (Core) service: Lowercase values for 'otelcol.component.kind' attributes. (#12865)
• (Core) service: Restrict the telemetry.newPipelineTelemetry feature gate to metrics. (#12856, #12933)
  The "off" state of this feature gate introduced a regression, where the Collector's internal logs were missing component attributes. See issue #12870 for more details on this bug.
  On the other hand, the "on" state introduced an issue with the Collector's default internal metrics, because the Prometheus exporter does not currently support instrumentation scope attributes.
  To solve both of these issues, this change turns on the new scope attributes for logs and traces by default regardless of the feature gate.
  However, the new scope attributes for metrics stay locked behind the feature gate, and will remain off by default until the Prometheus exporter is updated to support scope attributes.
  Please understand that enabling the telemetry.newPipelineTelemetry feature gate may break the export of Collector metrics through, depending on your configuration.
  Having a batch processor in multiple pipelines is a known trigger for this.
  This comes with a breaking change, where internal logs exported through OTLP will now use instrumentation scope attributes to identify the source component instead of log attributes.
  This does not affect the Collector's stderr output. See the changelog for v0.123.0 for a more detailed description of the gate's effects.
• (Contrib) receiver/k8sobjects: Check for K8s API objects existence on receiver startup and not during config validation. (#38803)
• (Contrib) receiver/kubeletstats: Move receiver.kubeletstats.enableCPUUsageMetrics feature gate to beta (#39487)
  Deprecated metrics container.cpu.utilization, k8s.pod.cpu.utilization and k8s.node.cpu.utilization are being replaced
  by container.cpu.usage, k8s.pod.cpu.usage and k8s.node.cpu.usage.
  To be able to use the deprecated metrics, switch receiver.kubeletstats.enableCPUUsageMetrics feature gate to false.
• (Contrib) processor/k8sattributes: Change processor/k8sattributes to return error if unset envvar is used for node_from_env_var (#39447)
  Before this was a valid configuration, but had an unexpected behavior to monitor the entire cluster. | To keep the same behavior simply do not set the node_from_env_var value or use empty string.
• (Contrib) receiver/sqlserver: host.name, sqlserver.computer.name, and sqlserver.instance.name are now resource attributes instead of log attributes. We used to report computer_name and instance_name in the log attributes for top query collection and they are now deprecated. Now we report the three resources attributes in both top query collection and sample query collection. (#39449)
  This change is only relevant for logs.

🚩 Deprecations 🚩

• (Contrib) connector/spanmetrics: Deprecate the unused configuration dimensions_cache_size (#39646)
  Deprecated configuration dimensions_cache_size, please use aggregation_cardinality_limit instead

💡 Enhancements 💡

• (Splunk) auto-instrumentation: Improve error message in case of failed .NET instrumentation installer download (#6165)
• (Splunk) auto-instrumentation: Update NodeJS instrumentation library to v3.1.2 (#6162)
• (Splunk) Update bundled OpenJDK to 11.0.27_6 (#6139)
• (Core) mdatagen: Add support for attributes for telemetry configuration in metadata. (#12919)
• (Core) configmiddleware: Add extensionmiddleware interface. (#12603, #9591)
• (Core) configgrpc: Add gRPC middleware support. (#12603, #9591)
• (Core) confighttp: Add HTTP middleware support. (#12603, #9591, #7441)
• (Core) configmiddleware: Add configmiddleware struct. (#12603, #9591)
• (Contrib) connector/spanmetrics: Add new aggregation_cardinality_limit configuration option to limit the number of unique combinations of dimensions that will be tracked for metrics aggregation. (#38990)
• (Contrib) connector/count: Add profiles support (#39577)
• (Contrib) extension/opamp: Introduces a new config field include_resource_attributes which allows the extension to copy the agent's resource attributes to the non-identifying attributes in the agent description. (#37487)
• (Contrib) receiver/statsd: Add new config to customize socket permissions when transport is set to unixgram. (#37807)
• (Contrib) receiver/kubeletstats: Adds support for collecting Node and Pod network IO/error metrics for all network interfaces (#30196)
• (Contrib) exporter/awss3: add configuration field resource_attrs_to_s3/s3_prefix to support mapping s3 bucket prefix to OTel resource attributes (#37858)
  If resource_attrs_to_s3/s3_prefix is configured, s3 prefix will be determined based on the specified resource attribute and s3uploader/s3_prefix will serve as a fallback.
• (Contrib) exporter/splunkhec: Use ObservedTimestamp if Timestamp is empty. (#39221)
• (Contrib) receiver/hostmetrics: Possible to enable the process scraper under FreeBSD in the hostmetrics receiver. (#39622)
• (Contrib) receiver/kafka: Add support for configuring Kafka consumer rebalance strategy and group instance ID (#39513)
  This enhancement introduces two optional settings: group_rebalance_strategy and group_instance_id.
  These allow users to override the default Range-based rebalance strategy and optionally provide a static instance ID (as per KIP-345) for cooperative sticky balancing.
  This is particularly useful when handling high-cardinality metric workloads, as it reduces rebalance impact, improves cache reuse, and boosts CPU efficiency.
  Both settings are optional to maintain full backward compatibility.
• (Contrib) receiver/kafka: Added a new 'topic' attribute to all existing internal consume-claim metrics. (#35336)
• (Contrib) receiver/kafka: Add max_fetch_wait config setting (#39360)
  This setting allows you to specify the maximum time that the broker will wait for
  min_fetch_size bytes of data to be available before sending a response to the client.
  Defaults to 250ms.
• (Contrib) receiver/sqlserver: Accept context_info with traceparent format in query sample collection, setting log record with correct traceId and spanId. (#39539)

🧰 Bug fixes 🧰

• (Splunk) receiver/smartagent: Fix the receiver failing to start by receiver_creator since 0.124.0 (#6187)
• (Core) exporterhelper: Do not ignore the num_consumers setting when batching is enabled. (#12244)
• (Core) exporterhelper: Reject elements larger than the queue capacity (#12847)
• (Core) mdatagen: Add time and plog package imports (#12907)
• (Core) confmap: Maintain nil values when marshaling or unmarshaling nil slices (#11882)
  Previously, nil slices were converted to empty lists, which are semantically different
  than a nil slice. This change makes this conversion more consistent when encoding
  or decoding config, and these values are now maintained.
• (Contrib) receiver/sqlquery: respect max_open_conn configuration for multiple queries (#39270)
• (Contrib) processor/resourcedetection: change the EKS cluster identifier and check the cluster version instead of the existence of aws-auth configmap (#39479)
• (Contrib) receiver/filelog: Fix frozen receiver when max_concurrent_files is 1 (#39598)
• (Contrib) processor/transform: Fix the context inferrer to also take into consideration the global OTTL conditions configuration. (#39455)
• (Contrib) receiver/prometheus: When a histogram metric has both classic and native histogram buckets, keep both, instead of throwing away the native histogram buckets. (#26555)
• (Contrib) receiver_creator: Fix how escaped backticks are handled in receiver creator templates (#39163)
• (Contrib) receiver/k8sobjects: Introduces error_mode, so users can choose between propagating, ignoring, or silencing missing objects. (#38803)
• (Contrib) extension/opamp: Skips loading TLS config for insecure endpoints (#39515)
• (Contrib) receiver/kafka: name label will be correctly set in receiver metrics (#39483)
• (Contrib) receiver/tcplog: Ignore SplitFuncBuilder field to prevent panic during config marshaling (#39474)

Docker Image Manifests:

• Linux (amd64, arm64, ppc64le) and Windows (2019 amd64, 2022 amd64):
  • quay.io/signalfx/splunk-otel-collector:0.125.0
  • digest: sha256:f599d05109d008a2f4a628327e2d0738937e4464e5f5552119b58c26f2d5cd0e
• Windows (2019 amd64, 2022 amd64):
  • quay.io/signalfx/splunk-otel-collector-windows:0.125.0
  • digest: sha256:a73cedffd21d43a456ccecda7fab5e0f64b0a7aadc48c00dce738471b27a8765