remote.kubernetes.configmap
General availability (GA)

remote.kubernetes.configmap

remote.kubernetes.configmap reads a ConfigMap from the Kubernetes API server and exposes its data for other components to consume.

This can be useful anytime Alloy needs data from a ConfigMap that is not directly mounted to the Alloy Pod.

Usage

alloy
remote.kubernetes.configmap "<LABEL>" {
  namespace = "<NAMESPACE_OF_CONFIGMAP>"
  name = "<NAME_OF_CONFIGMAP>"
}

Arguments

You can use the following arguments with remote.kubernetes.configmap:

NameTypeDescriptionDefaultRequired
namestringName of the Kubernetes ConfigMapyes
namespacestringKubernetes namespace containing the desired ConfigMap.yes
poll_frequencydurationFrequency to poll the Kubernetes API."1m"no
poll_timeoutdurationTimeout when polling the Kubernetes API."15s"no

When this component performs a poll operation, it requests the ConfigMap data from the Kubernetes API. 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.

Any error while polling will mark the component as unhealthy. After a successful poll, all data is exported with the same field names as the source ConfigMap.

Blocks

You can use the following blocks with remote.kubernetes.configmap:

BlockDescriptionRequired
clientConfigures Kubernetes client used to find Probes.no
client > authorizationConfigure generic authorization to the Kubernetes API.no
client > basic_authConfigure basic authentication to the Kubernetes API.no
client > oauth2Configure OAuth 2.0 for authenticating to the Kubernetes API.no
client > oauth2 > tls_configConfigure TLS settings for connecting to the Kubernetes API.no
client > tls_configConfigure TLS settings for connecting to the Kubernetes API.no

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

client

The client block configures the Kubernetes client used to discover Probes. If the client block isn’t provided, the default in-cluster configuration with the service account of the running Alloy Pod is used.

The following arguments are supported:

NameTypeDescriptionDefaultRequired
api_serverstringURL of the Kubernetes API server.no
bearer_token_filestringFile containing a bearer token to authenticate with.no
bearer_tokensecretBearer token to authenticate with.no
enable_http2boolWhether HTTP2 is supported for requests.trueno
follow_redirectsboolWhether redirects returned by the server should be followed.trueno
kubeconfig_filestringPath of the kubeconfig file to use for connecting to Kubernetes.no
no_proxystringComma-separated list of IP addresses, CIDR notations, and domain names to exclude from proxying.no
proxy_connect_headermap(list(secret))Specifies headers to send to proxies during CONNECT requests.no
proxy_from_environmentboolUse the proxy URL indicated by environment variables.falseno
proxy_urlstringHTTP proxy to send requests through.no

At most, one of the following can be provided:

no_proxy can contain IPs, CIDR notations, and domain names. IP and domain names can contain port numbers. proxy_url must be configured if no_proxy is configured.

proxy_from_environment uses the environment variables HTTP_PROXY, HTTPS_PROXY, and NO_PROXY (or the lowercase versions thereof). Requests use the proxy from the environment variable matching their scheme, unless excluded by NO_PROXY. proxy_url and no_proxy must not be configured if proxy_from_environment is configured.

proxy_connect_header should only be configured if proxy_url or proxy_from_environment are configured.

authorization

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

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

basic_auth

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

password and password_file are mutually exclusive, and only one can be provided inside a basic_auth block.

oauth2

NameTypeDescriptionDefaultRequired
client_idstringOAuth2 client ID.no
client_secret_filestringFile containing the OAuth2 client secret.no
client_secretsecretOAuth2 client secret.no
endpoint_paramsmap(string)Optional parameters to append to the token URL.no
proxy_urlstringHTTP proxy to send requests through.no
no_proxystringComma-separated list of IP addresses, CIDR notations, and domain names to exclude from proxying.no
proxy_from_environmentboolUse the proxy URL indicated by environment variables.falseno
proxy_connect_headermap(list(secret))Specifies headers to send to proxies during CONNECT requests.no
scopeslist(string)List of scopes to authenticate with.no
token_urlstringURL to fetch the token from.no

client_secret and client_secret_file are mutually exclusive, and only one can be provided inside an oauth2 block.

The oauth2 block may also contain a separate tls_config sub-block.

no_proxy can contain IPs, CIDR notations, and domain names. IP and domain names can contain port numbers. proxy_url must be configured if no_proxy is configured.

proxy_from_environment uses the environment variables HTTP_PROXY, HTTPS_PROXY, and NO_PROXY (or the lowercase versions thereof). Requests use the proxy from the environment variable matching their scheme, unless excluded by NO_PROXY. proxy_url and no_proxy must not be configured if proxy_from_environment is configured.

proxy_connect_header should only be configured if proxy_url or proxy_from_environment are configured.

tls_config

NameTypeDescriptionDefaultRequired
ca_pemstringCA PEM-encoded text to validate the server with.no
ca_filestringCA certificate to validate the server with.no
cert_pemstringCertificate PEM-encoded text for client authentication.no
cert_filestringCertificate file for client authentication.no
insecure_skip_verifyboolDisables validation of the server certificate.no
key_filestringKey file for client authentication.no
key_pemsecretKey PEM-encoded text for client authentication.no
min_versionstringMinimum acceptable TLS version.no
server_namestringServerName extension to indicate the name of the server.no

The following pairs of arguments are mutually exclusive and can’t both be set simultaneously:

  • ca_pem and ca_file
  • cert_pem and cert_file
  • key_pem and key_file

When configuring client authentication, both the client certificate (using cert_pem or cert_file) and the client key (using key_pem or key_file) must be provided.

When min_version isn’t 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
datamap(string)Data from the ConfigMap obtained from Kubernetes.

The data field contains a mapping from field names to values.

Component health

Instances of remote.kubernetes.configmap report as healthy if the most recent attempt to poll the kubernetes API succeeds.

Debug information

remote.kubernetes.configmap doesn’t expose any component-specific debug information.

Debug metrics

remote.kubernetes.configmap doesn’t expose any component-specific debug metrics.

Example

This example reads a Secret and a ConfigMap from Kubernetes and uses them to supply remote-write credentials.

alloy
remote.kubernetes.secret "credentials" {
  namespace = "monitoring"
  name = "metrics-secret"
}

remote.kubernetes.configmap "endpoint" {
  namespace = "monitoring"
  name = "metrics-endpoint"
}

prometheus.remote_write "default" {
  endpoint {
    url = remote.kubernetes.configmap.endpoint.data["url"]
    basic_auth {
      username = remote.kubernetes.configmap.endpoint.data["username"]
      password = remote.kubernetes.secret.credentials.data["password"]
    }
  }
}

This example assumes that the Secret and ConfigMap have already been created, and that the appropriate field names exist in their data.