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Open source

phlare.write

phlare.write receives performance profiles from other components and forwards them to a series of user-supplied endpoints using Phlare’ Push API.

Multiple phlare.write components can be specified by giving them different labels.

Usage

Alloy 
phlare.write "LABEL" {
  endpoint {
    url = PHLARE_URL

    ...
  }

  ...
}

Arguments

The following arguments are supported:

NameTypeDescriptionDefaultRequired
external_labelsmap(string)Labels to add to profiles sent over the network.no

Blocks

The following blocks are supported inside the definition of phlare.write:

HierarchyBlockDescriptionRequired
endpoint[endpoint][]Location to send profiles to.no
endpoint > http_client_config[http_client_config][]HTTP client settings when connecting to the endpoint.no
endpoint > http_client_config > basic_auth[basic_auth][]Configure basic_auth for authenticating to the endpoint.no
endpoint > http_client_config > authorization[authorization][]Configure generic authorization to the endpoint.no
endpoint > http_client_config > oauth2[oauth2][]Configure OAuth2 for authenticating to the endpoint.no
endpoint > http_client_config > oauth2 > tls_config[tls_config][]Configure TLS settings for connecting to the endpoint.no
endpoint > http_client_config > tls_config[tls_config][]Configure TLS settings for connecting to the endpoint.no

The > symbol indicates deeper levels of nesting. For example, endpoint > http_client_config refers to an http_client_config block defined inside an endpoint block.

endpoint block

The endpoint block describes a single location to send profiles to. Multiple endpoint blocks can be provided to send profiles to multiple locations.

The following arguments are supported:

NameTypeDescriptionDefaultRequired
urlstringFull URL to send metrics to.yes
namestringOptional name to identify the endpoint in metrics.no
remote_timeoutdurationTimeout for requests made to the URL."30s"no
headersmap(string)Extra headers to deliver with the request.no

When multiple endpoint blocks are provided, profiles are concurrently forwarded to all configured locations.

http_client_config block

The http_client_config configures settings used to connect to the remote_write server.

NameTypeDescriptionDefaultRequired
bearer_tokensecretBearer token to authenticate with.no
bearer_token_filestringFile containing a bearer token to authenticate with.no
proxy_urlstringHTTP proxy to proxy requests through.no
follow_redirectsboolWhether redirects returned by the server should be followed.trueno
enable_http_2boolWhether HTTP2 is supported for requests.trueno

bearer_token, bearer_token_file, basic_auth, authorization, and oauth2 are mutually exclusive and only one can be provided inside of a http_client_config block.

basic_auth block

NameTypeDescriptionDefaultRequired
usernamestringBasic auth username.no
passwordsecretBasic auth password.no
password_filestringFile containing the basic auth password.no

password and password_file are mututally exclusive and only one can be provided inside of a basic_auth block.

authorization block

NameTypeDescriptionDefaultRequired
typestringAuthorization type, for example, “Bearer”.no
credentialsecretSecret value.no
credentials_filestringFile containing the secret value.no

credential and credentials_file are mutually exclusive and only one can be provided inside of an authorization block.

oauth2 block

NameTypeDescriptionDefaultRequired
client_idstringOAuth2 client ID.no
client_secretsecretOAuth2 client secret.no
client_secret_filestringFile containing the OAuth2 client secret.no
scopeslist(string)List of scopes to authenticate with.no
token_urlstringURL to fetch the token from.no
endpoint_paramsmap(string)Optional parameters to append to the token URL.no
proxy_urlstringOptional proxy URL for OAuth2 requests.no

client_secret and client_secret_file are mututally exclusive and only one can be provided inside of an oauth2 block.

The oauth2 block may also contain its own separate tls_config sub-block.

tls_config block

NameTypeDescriptionDefaultRequired
ca_filestringCA certificate to validate the server with.no
cert_filestringCertificate file for client authentication.no
key_filestringKey file for client authentication.no
server_namestringServerName extension to indicate the name of the server.no
insecure_skip_verifyboolDisables validation of the server certificate.no
min_versionstringMinimum acceptable TLS version.no

When min_version is not provided, the minimum acceptable TLS version is inherited from Go’s default minimum version, TLS 1.2. If min_version is provided, it must be set to one of the following strings:

  • "TLS10" (TLS 1.0)
  • "TLS11" (TLS 1.1)
  • "TLS12" (TLS 1.2)
  • "TLS13" (TLS 1.3)

Exported fields

The following fields are exported and can be referenced by other components:

NameTypeDescription
receiverreceiverA value that other components can use to send profiles to.

Component health

phlare.write is only reported as unhealthy if given an invalid configuration. In those cases, exported fields are kept at their last healthy values.

Debug information

phlare.write does not expose any component-specific debug information.

Example

Alloy 
phlare.write "staging" {
  // Send metrics to a locally running Phlare instance.
  endpoint {
    url = "http://phlare:4100"
    headers = {
      "X-Scope-Org-ID" = "squad-1",
    }
  }
  external_labels = {
    "env" = "staging",
  }
}


phlare.scrape "default" {
  targets = [
    {"__address__" = "phlare:4100", "app"="phlare"},
    {"__address__" = "agent:12345", "app"="agent"},
  ]
  forward_to = [phlare.write.staging.receiver]
}