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Important: This documentation is about an older version. It's relevant only to the release noted, many of the features and functions have been updated or replaced. Please view the current version.

Open source

remote.http

remote.http exposes the response body of a URL to other components. The URL is polled for changes so that the most recent content is always available.

The most common use of remote.http is to load discovery targets from an HTTP server.

Multiple remote.http components can be specified by giving them different labels.

Usage

river
remote.http "LABEL" {
  url = "URL_TO_POLL"
}

Arguments

The following arguments are supported:

NameTypeDescriptionDefaultRequired
urlstringURL to poll.yes
poll_frequencydurationFrequency to poll the URL."1m"no
poll_timeoutdurationTimeout when polling the URL."10s"no
is_secretboolWhether the response body should be treated as a secret.falseno

When remote.http performs a poll operation, an HTTP GET request is made against the URL specified by the url argument. A poll is triggered by the following:

  • When the component first loads.
  • Every time the component’s arguments get re-evaluated.
  • At the frequency specified by the poll_frequency argument.

The poll is successful if the URL returns a 200 OK response code. All other response codes are treated as errors and mark the component as unhealthy. After a successful poll, the response body from the URL is exported.

Blocks

The following blocks are supported inside the definition of remote.http:

HierarchyBlockDescriptionRequired
clientclientHTTP client settings when connecting to the endpoint.no
client > basic_authbasic_authConfigure basic_auth for authenticating to the endpoint.no
client > authorizationauthorizationConfigure generic authorization to the endpoint.no
client > oauth2oauth2Configure OAuth2 for authenticating to the endpoint.no
client > oauth2 > tls_configtls_configConfigure TLS settings for connecting to the endpoint.no
client > tls_configtls_configConfigure TLS settings for connecting to the endpoint.no

The > symbol indicates deeper levels of nesting. For example, client > basic_auth refers to an basic_auth block defined inside a client block.

client block

The client block configures settings used to connect to the HTTP 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

The basic_auth block configures basic authentication to use when polling the configured URL.

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

The authorization block configures custom authorization to use when polling the configured URL.

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

The oauth2 block configures OAuth2 authorization to use when polling the configured URL.

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

The tls_config block configures TLS settings for connecting to HTTPS servers.

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 field is exported and can be referenced by other components:

NameTypeDescriptionDefaultRequired
contentstring or secretThe contents of the file.no

If the is_secret argument was true, content is a secret type.

Component health

Instances of remote.http report as healthy if the most recent HTTP GET request of the specified URL succeeds.

Debug information

remote.http does not expose any component-specific debug information.

Debug metrics

remote.http does not expose any component-specific debug metrics.

Example

This example reads a JSON array of objects from an endpoint and uses them as a set of scrape targets:

river
remote.http "targets" {
  url = env("MY_TARGETS_URL")
}

prometheus.scrape "default" {
  targets    = json_decode(remote.http.targets.content)
  forward_to = [prometheus.remote_write.default.receiver]
}

prometheus.remote_write "default" {
  client {
    url = env("PROMETHEUS_URL")
  }
}