otelcol.auth.bearer
otelcol.auth.bearer exposes a handler that other otelcol components can use to authenticate requests using bearer token authentication.
This component supports both server and client authentication.
Note
otelcol.auth.beareris a wrapper over the upstream OpenTelemetry Collectorbearertokenauthextension. Bug reports or feature requests will be redirected to the upstream repository, if necessary.
You can specify multiple otelcol.auth.bearer components by giving them different labels.
Usage
otelcol.auth.bearer "<LABEL>" {
token = "<TOKEN>"
}Arguments
You can use the following arguments with otelcol.auth.bearer:
| Name | Type | Description | Default | Required |
|---|---|---|---|---|
token | secret | Bearer token to use for authenticating requests. | yes | |
header | string | Specifies the auth header name. | "Authorization" | no |
scheme | string | Authentication scheme name. | "Bearer" | no |
When sending the token, the value of scheme is prepended to the token value.
The string is then sent out as either a header for HTTP or as metadata for gRPC.
If you use a file to store the token, you can use local.file to retrieve the token value from the file.
Blocks
You can use the following block with otelcol.auth.bearer:
| Block | Description | Required |
|---|---|---|
debug_metrics | Configures the metrics that this component generates to monitor its state. | no |
debug_metrics
The debug_metrics block configures the metrics that this component generates to monitor its state.
The following arguments are supported:
| Name | Type | Description | Default | Required |
|---|---|---|---|---|
disable_high_cardinality_metrics | boolean | Whether to disable certain high cardinality metrics. | true | no |
disable_high_cardinality_metrics is the Alloy equivalent to the telemetry.disableHighCardinalityMetrics feature gate in the OpenTelemetry Collector.
It removes attributes that could cause high cardinality metrics.
For example, attributes with IP addresses and port numbers in metrics about HTTP and gRPC connections are removed.
Note
If configured,
disable_high_cardinality_metricsonly applies tootelcol.exporter.*andotelcol.receiver.*components.
Exported fields
The following fields are exported and can be referenced by other components:
| Name | Type | Description |
|---|---|---|
handler | capsule(otelcol.Handler) | A value that other components can use to authenticate requests. |
Component health
otelcol.auth.bearer is only reported as unhealthy if given an invalid configuration.
Debug information
otelcol.auth.bearer doesn’t expose any component-specific debug information.
Examples
Default scheme via gRPC transport
The following example configures otelcol.exporter.otlp to use a bearer token authentication.
If you assume that the value of the API_KEY environment variable is SECRET_API_KEY, then the Authorization RPC metadata is set to Bearer SECRET_API_KEY.
otelcol.exporter.otlp "example" {
client {
endpoint = "my-otlp-grpc-server:4317"
auth = otelcol.auth.bearer.creds.handler
}
}
otelcol.auth.bearer "creds" {
token = sys.env("<API_KEY>")
}Custom scheme via HTTP transport
The following example configures otelcol.exporter.otlphttp to use a bearer token authentication.
If you assume that the value of the API_KEY environment variable is SECRET_API_KEY, then the Authorization HTTP header is set to MyScheme SECRET_API_KEY.
otelcol.exporter.otlphttp "example" {
client {
endpoint = "my-otlp-grpc-server:4317"
auth = otelcol.auth.bearer.creds.handler
}
}
otelcol.auth.bearer "creds" {
token = sys.env("<API_KEY>")
scheme = "MyScheme"
}


