Events and logs api

semantic_conventions/logs/events.yaml

@@ -0,0 +1,17 @@
+groups:
+  - id: event
+    prefix: event
+    brief: >
+        This document defines attributes for Events represented using Log Records.
+    attributes:
+      - id: name
+        type: string
+        requirement_level: required
+        brief: >
+          The name identifies the event.
+        examples: ['click', 'exception']
+      - id: domain
+        type: string
+        brief: >
+          The domain identifies the context in which an event happened. An event name is unique only within a domain.
+        examples: ['browser', 'mobile', 'kubernetes']

specification/logs/api.md

@@ -0,0 +1,65 @@
+## Events and Logs API Interface
+
+**Status**: [Experimental](../document-status.md)
+
+The Events and Logs API consist of these main classes:
+
+* LoggerProvider is the entry point of the API. It provides access to Loggers.
+* Logger is the class responsible for creating events and logs using Log records.
+
+LoggerProvider/Logger are analogous to TracerProvider/Tracer.
+
+![Events and Logs API classes](img/events-and-logs-api.png)
+
+### LoggerProvider
+
+Logger can be accessed with an LoggerProvider.
+
+In implementations of the API, the LoggerProvider is expected to be the stateful object that holds any configuration. (Note: The SDK implementation of this is what we currently call the [LogEmitterProvider](https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/logs/logging-library-sdk.md#logemitterprovider))
+
+Normally, the LoggerProvider is expected to be accessed from a central place. Thus, the API SHOULD provide a way to set/register and access a global default LoggerProvider.
+
+Notwithstanding any global LoggerProvider, some applications may want to or have to use multiple LoggerProvider instances, e.g. to have different configuration (like LogRecordProcessors) for each (and consequently for the Loggers obtained from them), or because it's easier with dependency injection frameworks. Thus, implementations of LoggerProvider SHOULD allow creating an arbitrary number of instances.
+
+#### LoggerProvider operations
+
+The LoggerProvider MUST provide the following functions:
+
+* Get a Logger
+
+##### Get a Logger
+
+This API MUST accept the following parameters that determine the scope for the `Logger` returned. Most of these are common with the scope parameters for `Tracer` and `Meter`, except for `event_domain` and `include_trace_context` which is specific to `Logger`.
+
+- `name` (required): This name SHOULD uniquely identify the [instrumentation scope](../glossary.md#instrumentation-scope), such as the [instrumentation library](../glossary.md#instrumentation-library) (e.g. `io.opentelemetry.contrib.mongodb`), package, module or class name.  If an application or library has built-in OpenTelemetry instrumentation, both [Instrumented library](../glossary.md#instrumented-library) and [Instrumentation library](../glossary.md#instrumentation-library) may refer to the same library. In that scenario, the `name` denotes a module name or component name within that library or application. In case an invalid name (null or empty string) is specified, a working Logger implementation MUST be returned as a fallback rather than returning null or throwing an exception, its `name` property SHOULD be set to an empty string, and a message reporting that the specified value is invalid SHOULD be logged. A library implementing the OpenTelemetry API may also ignore this name and return a default instance for all calls, if it does not support "named" functionality (e.g. an implementation which is not even observability-related). A LoggerProvider could also return a no-op Logger here if application owners configure the SDK to suppress telemetry produced by this library.
+
+- `version` (optional): Specifies the version of the instrumentation scope if the scope has a version (e.g. a library version). Example value: 1.0.0.
+- `schema_url` (optional): Specifies the Schema URL that should be recorded in the emitted telemetry
+- `event_domain` (optional): Specifies the domain for the events created, which should be added in the attribute `event.domain` in the instrumentation scope.
+- `include_trace_context` (optional): Specifies whether the Trace Context should automatically be passed on to the events and logs created by the Logger. This SHOULD be false by default.
+- `attributes` (optional): Specifies the instrumentation scope attributes to associate with emitted telemetry.
+
+Implementations MUST return different `Logger` instances when called repeatedly with different values of parameters. Note that always returning a new `Logger` instance is a valid implementation. The only exception to this rule is the no-op `Logger`: implementations MAY return the same instance regardless of parameter values.
+
+Implementations MUST NOT require users to repeatedly obtain an Logger again with the same name+version+schema_url+event_domain+include_trace_context+attributes to pick up configuration changes. This can be achieved either by allowing to work with an outdated configuration or by ensuring that new configuration applies also to previously returned Loggers.
+
+Note: This could, for example, be implemented by storing any mutable configuration in the LoggerProvider and having Logger implementation objects have a reference to the LoggerProvider from which they were obtained. If configuration must be stored per-Logger (such as disabling a certain Logger), the Logger could, for example, do a look-up with its name+version+schema_url+event_domain+include_trace_context+attributes in a map in the LoggerProvider, or the LoggerProvider could maintain a registry of all returned Loggers and actively update their configuration if it changes.
+
+The effect of associating a Schema URL with a Logger MUST be that the telemetry emitted using the Logger will be associated with the Schema URL, provided that the emitted data format is capable of representing such association.
+
+### Logger
+
+The Logger is responsible for creating Events and Logs.
+
+Note that Loggers should not be responsible for configuration. This should be the responsibility of the LoggerProvider instead.
+
+#### Logger operations
+
+The Logger MUST provide functions to:
+
+- Create an `Event` and emit it to the processing pipeline.
+  - The API MUST accept an event name as a parameter. The event name provided should be inserted as an attribute with key `event.name`. Care MUST be taken to not override or delete this attribute while the `Event` is created.  This function MAY be named `logEvent`.
+- Create a `Log Record` and emit it to the processing pipeline.
+  - This function MAY be named `logRecord`.
+  - The intended users of this API is Log Appenders.
+

specification/logs/semantic_conventions/README.md

@@ -6,6 +6,11 @@ The following semantic conventions for logs are defined:
 
 * [Log Media](media.md): Semantic attributes that may be used in describing the source of a log.
 
+The following semantic conventions for events are defined:
+
+* [Events](events.md): Semantic attributes that must be used to represent Events using log data model.
+
+
 Apart from semantic conventions for logs, [traces](../../trace/semantic_conventions/README.md), and [metrics](../../metrics/semantic_conventions/README.md),
 OpenTelemetry also defines the concept of overarching [Resources](../../resource/sdk.md) with their own
 [Resource Semantic Conventions](../../resource/semantic_conventions/README.md).

specification/logs/semantic_conventions/events.md

@@ -0,0 +1,19 @@
+# Semantic Convention for event attributes
+
+**Status**: [Experimental](../../document-status.md)
+
+This document describes the attributes of standalone Events that are represented by `LogRecord`s. All standalone Events have a name and a domain. The Event domain is used as a mechanism to avoid conflicts with event names.
+
+**type:** `event`
+
+**Description:** Event attributes.
+
+| Attribute  | Type | Description  | Examples  | Required |
+|---|---|---|---|---|
+| `event.name` | string | Name or type of the event. | `network-change`; `button-click`; `exception` | Yes |
+| `event.domain` | string | Domain or scope for the event. | `profiling`; `browser`, `db`, `k8s` | No |
+
+An `event.name` is supposed to be unique only in the context of an `event.domain`, so this allows for two events in different domains to have same `event.name`, yet be unrelated events. No claim is made about the uniqueness of `event.name`s in the absence of `event.domain`.
+
+Note that Scope attributes are equivalent to the attributes at Span and LogRecord level, so recording the attribute `event.domain` on the Scope is equivalent to recording it on Spans and LogRecords within the Scope.
+