Add log attribute limit configuration

CHANGELOG.md

@@ -119,6 +119,9 @@ release.
 
 - Specify handling of invalid numeric environment variables
   ([#2963](https://github.com/open-telemetry/opentelemetry-specification/pull/2963))
+- Add log-specific attribute limit configuration and clarify that general
+  attribute limit configuration also apply to log records.
+  ([#2861](https://github.com/open-telemetry/opentelemetry-specification/pull/2861))
 
 ### Telemetry Schemas
 

specification/common/README.md

@@ -91,11 +91,11 @@ limits programmatically. Names of the configuration options SHOULD be the same a
 in the list below.
 
 An SDK MAY implement model-specific limits, for example
-`SpanAttributeCountLimit`. If both a general and a model-specific limit are
-implemented, then the SDK MUST first attempt to use the model-specific limit, if
-it isn't set, then the SDK MUST attempt to use the general limit. If neither are
-defined, then the SDK MUST try to use the model-specific limit default value,
-followed by the global limit default value.
+`SpanAttributeCountLimit` or `LogRecordAttributeCountLimit`. If both a general
+and a model-specific limit are implemented, then the SDK MUST first attempt to
+use the model-specific limit, if it isn't set, then the SDK MUST attempt to use
+the general limit. If neither are defined, then the SDK MUST try to use the
+model-specific limit default value, followed by the global limit default value.
 
 #### Configurable Parameters
 

specification/logs/sdk.md

@@ -14,6 +14,7 @@
 - [Additional LogRecord interfaces](#additional-logrecord-interfaces)
   * [ReadableLogRecord](#readablelogrecord)
   * [ReadWriteLogRecord](#readwritelogrecord)
+- [LogRecord Limits](#logrecord-limits)
 - [LogRecordProcessor](#logrecordprocessor)
   * [LogRecordProcessor operations](#logrecordprocessor-operations)
     + [OnEmit](#onemit)
@@ -130,6 +131,36 @@ information
 that was added to the `LogRecord` (as with
 [ReadableLogRecord](#readablelogrecord)).
 
+## LogRecord Limits
+
+`LogRecord` attributes MUST adhere to the [common rules of attribute limits](../common/README.md#attribute-limits).
+
+If the SDK implements attribute limits it MUST provide a way to change these
+limits, via a configuration to the `LoggerProvider`, by allowing users to
+configure individual limits like in the Java example below.
+
+The options MAY be bundled in a class, which then SHOULD be called
+`LogRecordLimits`.
+
+```java
+public final class LogRecordLimits {
+  LogRecordLimits(int attributeCountLimit, int attributeValueLengthLimit);
+
+  public int getAttributeCountLimit();
+
+  public int getAttributeValueLengthLimit();
+}
+```
+
+**Configurable parameters:**
+
+* [all common options applicable to attributes](../common/README.md#configurable-parameters)
+
+There SHOULD be a message printed in the SDK's log to indicate to the user
+that an attribute was discarded due to such a limit.
+To prevent excessive logging, the message should be printed at most once per
+`LogRecord` (i.e., not per discarded attribute.)
+
 ## LogRecordProcessor
 
 `LogRecordProcessor` is an interface which allows hooks for `LogRecord`

specification/sdk-environment-variables.md

@@ -157,6 +157,17 @@ See the SDK [Span Limits](trace/sdk.md#span-limits) section for the definition o
 | OTEL_EVENT_ATTRIBUTE_COUNT_LIMIT       | Maximum allowed attribute per span event count | 128     |       |
 | OTEL_LINK_ATTRIBUTE_COUNT_LIMIT        | Maximum allowed attribute per span link count  | 128     |       |
 
+## LogRecord Limits
+
+**Status**: [Experimental](document-status.md)
+
+See the SDK [LogRecord Limits](logs/sdk.md#logrecord-limits) section for the definition of the limits.
+
+| Name                                        | Description                                | Default  | Notes |
+| ------------------------------------------- | -------------------------------------------| -------- | ----- |
+| OTEL_LOGRECORD_ATTRIBUTE_VALUE_LENGTH_LIMIT | Maximum allowed attribute value size       | no limit |       |
+| OTEL_LOGRECORD_ATTRIBUTE_COUNT_LIMIT        | Maximum allowed log record attribute count | 128      |       |
+
 ## OTLP Exporter
 
 See [OpenTelemetry Protocol Exporter Configuration Options](./protocol/exporter.md).

specification/trace/sdk.md

@@ -377,23 +377,25 @@ Following configuration properties should be available when creating the sampler
 
 Span attributes MUST adhere to the [common rules of attribute limits](../common/README.md#attribute-limits).
 
+If the SDK implements attribute limits it MUST provide a way to change these
+limits, via a configuration to the `TracerProvider`, by allowing users to
+configure individual limits like in the Java example below.
+
 SDK Spans MAY also discard links and events that would increase the number of
 elements of each collection beyond the configured limit.
 
-If the SDK implements the limits above it MUST provide a way to change these
-limits, via a configuration to the TracerProvider, by allowing users to
-configure individual limits like in the Java example bellow.
-
-The name of the configuration options SHOULD be `EventCountLimit` and `LinkCountLimit`. The options MAY be bundled in a class,
-which then SHOULD be called `SpanLimits`. Implementations MAY provide additional
-configuration such as `AttributePerEventCountLimit` and `AttributePerLinkCountLimit`.
+The options MAY be bundled in a class, which then SHOULD be called `SpanLimits`.
+Implementations MAY provide additional configuration such as
+`AttributePerEventCountLimit` and `AttributePerLinkCountLimit`.
 
 ```java
 public final class SpanLimits {
-  SpanLimits(int attributeCountLimit, int linkCountLimit, int eventCountLimit);
+  SpanLimits(int attributeCountLimit, int attributeValueLengthLimit, int linkCountLimit, int eventCountLimit);
 
   public int getAttributeCountLimit();
 
+  public int getAttributeValueLengthLimit();
+
   public int getAttributeCountPerEventLimit();
 
   public int getAttributeCountPerLinkLimit();
@@ -414,7 +416,8 @@ public final class SpanLimits {
 
 There SHOULD be a log emitted to indicate to the user that an attribute, event,
 or link was discarded due to such a limit. To prevent excessive logging, the log
-should not be emitted once per span, or per discarded attribute, event, or links.
+should be emitted at most once per span (i.e., not per discarded attribute,
+event, or link).
 
 ## Id Generators