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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.
discovery.dockerswarm
discovery.dockerswarm
allows you to retrieve scrape targets from Docker Swarm.
Usage
discovery.dockerswarm "LABEL" {
host = "DOCKER_DAEMON_HOST"
role = "SWARM_ROLE"
}
Arguments
The following arguments are supported:
Name | Type | Description | Default | Required |
---|---|---|---|---|
host | string | Address of the Docker daemon. | yes | |
role | string | Role of the targets to retrieve. Must be services , tasks , or nodes . | yes | |
port | number | The port to scrape metrics from, when role is nodes, and for discovered tasks and services that don’t have published ports. | 80 | no |
refresh_interval | duration | Interval at which to refresh the list of targets. | "60s" | no |
bearer_token_file | string | File containing a bearer token to authenticate with. | no | |
bearer_token | secret | Bearer token to authenticate with. | no | |
enable_http2 | bool | Whether HTTP2 is supported for requests. | true | no |
follow_redirects | bool | Whether redirects returned by the server should be followed. | true | no |
proxy_url | string | HTTP proxy to send requests through. | no | |
no_proxy | string | Comma-separated list of IP addresses, CIDR notations, and domain names to exclude from proxying. | no | |
proxy_from_environment | bool | Use the proxy URL indicated by environment variables. | false | no |
proxy_connect_header | map(list(secret)) | Specifies headers to send to proxies during CONNECT requests. | 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.
Blocks
The following blocks are supported inside the definition of
discovery.dockerswarm
:
Hierarchy | Block | Description | Required |
---|---|---|---|
filter | filter | Optional filter to limit the discovery process to a subset of available resources. | no |
basic_auth | basic_auth | Configure basic_auth for authenticating to the endpoint. | no |
authorization | authorization | Configure generic authorization to the endpoint. | no |
oauth2 | oauth2 | Configure OAuth2 for authenticating to the endpoint. | no |
oauth2 > tls_config | tls_config | Configure TLS settings for connecting to the endpoint. | no |
tls_config | tls_config | Configure TLS settings for connecting to the endpoint. | no |
The >
symbol indicates deeper levels of nesting. For example,
oauth2 > tls_config
refers to a tls_config
block defined inside
an oauth2
block.
filter block
Filters can be used to limit the discovery process to a subset of available resources.
It is possible to define multiple filter
blocks within the discovery.dockerswarm
block.
The list of available filters depends on the role
:
The following arguments can be used to configure a filter.
Name | Type | Description | Default | Required |
---|---|---|---|---|
name | string | Name of the filter. | yes | |
values | list(string) | List of values associated with the filter. | yes |
basic_auth block
Name | Type | Description | Default | Required |
---|---|---|---|---|
password_file | string | File containing the basic auth password. | no | |
password | secret | Basic auth password. | no | |
username | string | Basic auth username. | no |
password
and password_file
are mutually exclusive, and only one can be provided inside a basic_auth
block.
authorization block
Name | Type | Description | Default | Required |
---|---|---|---|---|
credentials_file | string | File containing the secret value. | no | |
credentials | secret | Secret value. | no | |
type | string | Authorization type, for example, “Bearer”. | no |
credential
and credentials_file
are mutually exclusive, and only one can be provided inside an authorization
block.
oauth2 block
Name | Type | Description | Default | Required |
---|---|---|---|---|
client_id | string | OAuth2 client ID. | no | |
client_secret_file | string | File containing the OAuth2 client secret. | no | |
client_secret | secret | OAuth2 client secret. | no | |
endpoint_params | map(string) | Optional parameters to append to the token URL. | no | |
proxy_url | string | HTTP proxy to send requests through. | no | |
no_proxy | string | Comma-separated list of IP addresses, CIDR notations, and domain names to exclude from proxying. | no | |
proxy_from_environment | bool | Use the proxy URL indicated by environment variables. | false | no |
proxy_connect_header | map(list(secret)) | Specifies headers to send to proxies during CONNECT requests. | no | |
scopes | list(string) | List of scopes to authenticate with. | no | |
token_url | string | URL 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 block
Name | Type | Description | Default | Required |
---|---|---|---|---|
ca_pem | string | CA PEM-encoded text to validate the server with. | no | |
ca_file | string | CA certificate to validate the server with. | no | |
cert_pem | string | Certificate PEM-encoded text for client authentication. | no | |
cert_file | string | Certificate file for client authentication. | no | |
insecure_skip_verify | bool | Disables validation of the server certificate. | no | |
key_file | string | Key file for client authentication. | no | |
key_pem | secret | Key PEM-encoded text for client authentication. | no | |
min_version | string | Minimum acceptable TLS version. | no | |
server_name | string | ServerName 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
andca_file
cert_pem
andcert_file
key_pem
andkey_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
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:
Name | Type | Description |
---|---|---|
targets | list(map(string)) | The set of targets discovered from Swarm. |
Roles
The role
attribute decides the role of the targets to retrieve.
services
The services
role discovers all Swarm services and exposes their ports as targets. For each published port of a service, a single target is generated. If a service has no published ports, a target per service is created using the port
attribute defined in the arguments.
Available meta labels:
__meta_dockerswarm_service_id
: the ID of the service.__meta_dockerswarm_service_name
: the name of the service.__meta_dockerswarm_service_mode
: the mode of the service.__meta_dockerswarm_service_endpoint_port_name
: the name of the endpoint port, if available.__meta_dockerswarm_service_endpoint_port_publish_mode
: the publish mode of the endpoint port.__meta_dockerswarm_service_label_<labelname>
: each label of the service.__meta_dockerswarm_service_task_container_hostname
: the container hostname of the target, if available.__meta_dockerswarm_service_task_container_image
: the container image of the target.__meta_dockerswarm_service_updating_status
: the status of the service, if available.__meta_dockerswarm_network_id
: the ID of the network.__meta_dockerswarm_network_name
: the name of the network.__meta_dockerswarm_network_ingress
: whether the network is ingress.__meta_dockerswarm_network_internal
: whether the network is internal.__meta_dockerswarm_network_label_<labelname>
: each label of the network.__meta_dockerswarm_network_scope
: the scope of the network.
tasks
The tasks
role discovers all Swarm tasks and exposes their ports as targets. For each published port of a task, a single target is generated. If a task has no published ports, a target per task is created using the port
attribute defined in the arguments.
Available meta labels:
__meta_dockerswarm_container_label_<labelname>
: each label of the container.__meta_dockerswarm_task_id
: the ID of the task.__meta_dockerswarm_task_container_id
: the container ID of the task.__meta_dockerswarm_task_desired_state
: the desired state of the task.__meta_dockerswarm_task_slot
: the slot of the task.__meta_dockerswarm_task_state
: the state of the task.__meta_dockerswarm_task_port_publish_mode
: the publish mode of the task port.__meta_dockerswarm_service_id
: the ID of the service.__meta_dockerswarm_service_name
: the name of the service.__meta_dockerswarm_service_mode
: the mode of the service.__meta_dockerswarm_service_label_<labelname>
: each label of the service.__meta_dockerswarm_network_id
: the ID of the network.__meta_dockerswarm_network_name
: the name of the network.__meta_dockerswarm_network_ingress
: whether the network is ingress.__meta_dockerswarm_network_internal
: whether the network is internal.__meta_dockerswarm_network_label_<labelname>
: each label of the network.__meta_dockerswarm_network_label
: each label of the network.__meta_dockerswarm_network_scope
: the scope of the network.__meta_dockerswarm_node_id
: the ID of the node.__meta_dockerswarm_node_hostname
: the hostname of the node.__meta_dockerswarm_node_address
: the address of the node.__meta_dockerswarm_node_availability
: the availability of the node.__meta_dockerswarm_node_label_<labelname>
: each label of the node.__meta_dockerswarm_node_platform_architecture
: the architecture of the node.__meta_dockerswarm_node_platform_os
: the operating system of the node.__meta_dockerswarm_node_role
: the role of the node.__meta_dockerswarm_node_status
: the status of the node.
The __meta_dockerswarm_network_*
meta labels are not populated for ports which are published with mode=host.
nodes
The nodes
role is used to discover Swarm nodes.
Available meta labels:
__meta_dockerswarm_node_address
: the address of the node.__meta_dockerswarm_node_availability
: the availability of the node.__meta_dockerswarm_node_engine_version
: the version of the node engine.__meta_dockerswarm_node_hostname
: the hostname of the node.__meta_dockerswarm_node_id
: the ID of the node.__meta_dockerswarm_node_label_<labelname>
: each label of the node.__meta_dockerswarm_node_manager_address
: the address of the manager component of the node.__meta_dockerswarm_node_manager_leader
: the leadership status of the manager component of the node (true or false).__meta_dockerswarm_node_manager_reachability
: the reachability of the manager component of the node.__meta_dockerswarm_node_platform_architecture
: the architecture of the node.__meta_dockerswarm_node_platform_os
: the operating system of the node.__meta_dockerswarm_node_role
: the role of the node.__meta_dockerswarm_node_status
: the status of the node.
Component health
discovery.dockerswarm
is only reported as unhealthy when given an invalid
configuration. In those cases, exported fields retain their last healthy
values.
Debug information
discovery.dockerswarm
does not expose any component-specific debug information.
Debug metrics
discovery.dockerswarm
does not expose any component-specific debug metrics.
Example
This example discovers targets from Docker Swarm tasks:
discovery.dockerswarm "example" {
host = "unix:///var/run/docker.sock"
role = "tasks"
filter {
name = "id"
values = ["0kzzo1i0y4jz6027t0k7aezc7"]
}
filter {
name = "desired-state"
values = ["running", "accepted"]
}
}
prometheus.scrape "demo" {
targets = discovery.dockerswarm.example.targets
forward_to = [prometheus.remote_write.demo.receiver]
}
prometheus.remote_write "demo" {
endpoint {
url = PROMETHEUS_REMOTE_WRITE_URL
basic_auth {
username = USERNAME
password = PASSWORD
}
}
}
Replace the following:
PROMETHEUS_REMOTE_WRITE_URL
: The URL of the Prometheus remote_write-compatible server to send metrics to.USERNAME
: The username to use for authentication to the remote_write API.PASSWORD
: The password to use for authentication to the remote_write API.
Compatible components
discovery.dockerswarm
has exports that can be consumed by the following components:
- Components that consume Targets
Note
Connecting some components may not be sensible or components may require further configuration to make the connection work correctly. Refer to the linked documentation for more details.