go.opentelemetry.io/collector/receiver (go): Package receiver defines components that allows the collector to receive metrics, traces and logs.  Receiver receives data from a source (either from a remote source via network or scrapes from a local host) and pushes the data to the pipelines it is attached to by calling the nextConsumer.Consume*() function.  The nextConsumer.Consume*() function may return an error to indicate that the data was not accepted. There are 2 types of possible errors: Permanent and non-Permanent. The receiver must check the type of the error using IsPermanent() helper.  If the error is Permanent, then the nextConsumer.Consume*() call should not be retried with the same data. This typically happens when the data cannot be serialized by the exporter that is attached to the pipeline or when the destination refuses the data because it cannot decode it. The receiver must indicate to the source from which it received the data that the received data was bad, if the receiving protocol allows to do that. In case of OTLP/HTTP for example, this means that HTTP 400 response is returned to the sender.  If the error is non-Permanent then the nextConsumer.Consume*() call should be retried with the same data. This may be done by the receiver itself, however typically it is done by the original sender, after the receiver returns a response to the sender indicating that the Collector is currently overloaded and the request must be retried. In case of OTLP/HTTP for example, this means that HTTP 429 or 503 response is returned.  The receivers that receive data via a network protocol that support acknowledgments MUST follow this order of operations:  This ensures there are strong delivery guarantees once the data is acknowledged by the Collector.  Similarly, receivers that use checkpointing to remember the position of last processed data (e.g. via storage extension) MUST store the checkpoint only AFTER the Consume*() call returns.
Keywords: metrics|monitoring|observability|open-telemetry|opentelemetry|telemetry