[exporter/splunk_hec] Update limits for max_content_length settings (o…

…pen-telemetry#11550)

Splunk Core/Cloud support request payloads up to 800 Mb (https://docs.splunk.com/Documentation/Splunk/8.2.2/Admin/Limitsconf#.5Bhttp_input.5D), but the exporter currently doesn't allow sending payloads more than 2 Mb due to a Splunk Observability ingest limitation. This change updates the limits to make it possible to send bigger requests.

CHANGELOG.md

@@ -23,6 +23,7 @@
 - `saphanareceiver`: Fix component memory query, add better error handling (#11507)
 - `sqlqueryreceiver`: Add core functionality to SQL query receiver (#10867)
 - `sapmexporter`: Add config option to log responses from Splunk APM. (#11425)
+- `splunkhecexporter`: Update limits for max_content_length settings (#11550)
 - `filterprocessor`: Add ability to filter `Spans` (#6341)
 - `prometheusexporter` : Added a feature to prometheusexporter to export exemplars along with histogram metrics (#9945)
 - `tracegen`: support add additional resource attributes. (#11145)

exporter/splunkhecexporter/README.md

@@ -27,8 +27,16 @@ The following configuration options can also be configured:
 - `ca_file` (no default) Path to the CA cert to verify the server being connected to.
 - `cert_file` (no default) Path to the TLS cert to use for client connections when TLS client auth is required.
 - `key_file` (no default) Path to the TLS key to use for TLS required connections.
-- `max_content_length_logs` (default: 2097152): Maximum log data size in bytes per HTTP post limited to 2097152 bytes (2 MiB).
-- `max_content_length_metrics` (default: 2097152): Maximum metric data size in bytes per HTTP post limited to 2097152 bytes (2 MiB).
+- `max_content_length_logs` (default: 2097152): Maximum log payload size in bytes. Log batches of bigger size will be
+ broken down into several requests. Default value is 2097152 bytes (2 MiB). Maximum allowed value is 838860800
+ (~ 800 MB). Keep in mind that Splunk Observability backend doesn't accept requests bigger than 2 MiB. This
+ configuration value can be raised only if used with Splunk Core/Cloud.
+- `max_content_length_metrics` (default: 2097152): Maximum metric payload size in bytes. Metric batches of bigger size
+ will be broken down into several requests. Default value is 2097152 bytes (2 MiB). Maximum allowed value is 838860800
+ (~ 800 MB).
+- `max_content_length_metrics` (default: 2097152): Maximum trace payload size in bytes. Trace batches of bigger size
+ will be broken down into several requests. Default value is 2097152 bytes (2 MiB). Maximum allowed value is 838860800
+ (~ 800 MB).
 - `splunk_app_name` (default: "OpenTelemetry Collector Contrib") App name is used to track telemetry information for Splunk App's using HEC by App name.
 - `splunk_app_version` (default: Current OpenTelemetry Collector Contrib Build Version): App version is used to track telemetry information for Splunk App's using HEC by App version. 
 - `log_data_enabled` (default: true): Specifies whether the log data is exported. Set it to `false` if you want the log 

exporter/splunkhecexporter/config.go

@@ -29,10 +29,13 @@ import (
 
 const (
  // hecPath is the default HEC path on the Splunk instance.
- hecPath = "services/collector"
- maxContentLengthLogsLimit = 2 * 1024 * 1024
- maxContentLengthMetricsLimit = 2 * 1024 * 1024
- maxContentLengthTracesLimit = 2 * 1024 * 1024
+ hecPath = "services/collector"
+ defaultContentLengthLogsLimit = 2 * 1024 * 1024
+ defaultContentLengthMetricsLimit = 2 * 1024 * 1024
+ defaultContentLengthTracesLimit = 2 * 1024 * 1024
+ maxContentLengthLogsLimit = 800 * 1024 * 1024
+ maxContentLengthMetricsLimit = 800 * 1024 * 1024
+ maxContentLengthTracesLimit = 800 * 1024 * 1024
 )
 
 // OtelToHecFields defines the mapping of attributes to HEC fields
@@ -80,13 +83,16 @@ type Config struct {
  // Disable GZip compression. Defaults to false.
  DisableCompression bool `mapstructure:"disable_compression"`
 
- // Maximum log data size in bytes per HTTP post. Defaults to the backend limit of 2097152 bytes (2MiB).
+ // Maximum log payload size in bytes. Default value is 2097152 bytes (2MiB).
+ // Maximum allowed value is 838860800 (~ 800 MB).
  MaxContentLengthLogs uint `mapstructure:"max_content_length_logs"`
 
- // Maximum metric data size in bytes per HTTP post. Defaults to the backend limit of 2097152 bytes (2MiB).
+ // Maximum metric payload size in bytes. Default value is 2097152 bytes (2MiB).
+ // Maximum allowed value is 838860800 (~ 800 MB).
  MaxContentLengthMetrics uint `mapstructure:"max_content_length_metrics"`
 
- // Maximum trace data size in bytes per HTTP post. Defaults to the backend limit of 2097152 bytes (2MiB).
+ // Maximum trace payload size in bytes. Default value is 2097152 bytes (2MiB).
+ // Maximum allowed value is 838860800 (~ 800 MB).
  MaxContentLengthTraces uint `mapstructure:"max_content_length_traces"`
 
  // TLSSetting struct exposes TLS client configuration.

exporter/splunkhecexporter/factory.go

@@ -70,9 +70,9 @@ func createDefaultConfig() config.Exporter {
  QueueSettings: exporterhelper.NewDefaultQueueSettings(),
  DisableCompression: false,
  MaxConnections: defaultMaxIdleCons,
- MaxContentLengthLogs: maxContentLengthLogsLimit,
- MaxContentLengthMetrics: maxContentLengthMetricsLimit,
- MaxContentLengthTraces: maxContentLengthTracesLimit,
+ MaxContentLengthLogs: defaultContentLengthLogsLimit,
+ MaxContentLengthMetrics: defaultContentLengthMetricsLimit,
+ MaxContentLengthTraces: defaultContentLengthTracesLimit,
  HecToOtelAttrs: splunk.HecToOtelAttrs{
  Source: splunk.DefaultSourceLabel,
  SourceType: splunk.DefaultSourceTypeLabel,