open-consul/website/source/api/agent/service.html.md

layout	page_title	sidebar_current	description
api	Service - Agent - HTTP API	api-agent-service	The /agent/service endpoints interact with services on the local agent in Consul.

Service - Agent HTTP API

The /agent/service endpoints interact with services on the local agent in Consul. These should not be confused with services in the catalog.

List Services

This endpoint returns all the services that are registered with the local agent. These services were either provided through configuration files or added dynamically using the HTTP API.

It is important to note that the services known by the agent may be different from those reported by the catalog. This is usually due to changes being made while there is no leader elected. The agent performs active anti-entropy, so in most situations everything will be in sync within a few seconds.

Method	Path	Produces
GET	/agent/services	application/json

The table below shows this endpoint's support for blocking queries, consistency modes, agent caching, and required ACLs.

Blocking Queries	Consistency Modes	Agent Caching	ACL Required
NO	none	none	service:read

Parameters

• filter (string: "") - Specifies the expression used to filter the queries results prior to returning the data.

Sample Request

$ curl \
    http://127.0.0.1:8500/v1/agent/services

Sample Response

{
  "redis": {
      "ID": "redis",
      "Service": "redis",
      "Tags": [],
      "Meta": {
          "redis_version": "4.0"
      },
      "Port": 8000,
      "Address": "",
      "EnableTagOverride": false,
      "Weights": {
          "Passing": 10,
          "Warning": 1
      }
  }
}

Filtering

The filter is executed against each value in the service mapping with the following selectors and filter operations being supported:

Selector	Supported Operations
Address	Equal, Not Equal
Connect.Native	Equal, Not Equal
EnableTagOverride	Equal, Not Equal
ID	Equal, Not Equal
Kind	Equal, Not Equal
Meta	In, Not In, Is Empty, Is Not Empty
Meta.<any>	Equal, Not Equal
Port	Equal, Not Equal
Proxy.DestinationServiceID	Equal, Not Equal
Proxy.DestinationServiceName	Equal, Not Equal
Proxy.LocalServiceAddress	Equal, Not Equal
Proxy.LocalServicePort	Equal, Not Equal
Proxy.Upstreams	Is Empty, Is Not Empty
Proxy.Upstreams.Datacenter	Equal, Not Equal
Proxy.Upstreams.DestinationName	Equal, Not Equal
Proxy.Upstreams.DestinationNamespace	Equal, Not Equal
Proxy.Upstreams.DestinationType	Equal, Not Equal
Proxy.Upstreams.LocalBindAddress	Equal, Not Equal
Proxy.Upstreams.LocalBindPort	Equal, Not Equal
Service	Equal, Not Equal
Tags	In, Not In, Is Empty, Is Not Empty
Weights.Passing	Equal, Not Equal
Weights.Warning	Equal, Not Equal

Get Service Configuration

This endpoint was added in Consul 1.3.0 and returns the full service definition for a single service instance registered on the local agent. It is used by Connect proxies to discover the embedded proxy configuration that was registered with the instance.

It is important to note that the services known by the agent may be different from those reported by the catalog. This is usually due to changes being made while there is no leader elected. The agent performs active anti-entropy, so in most situations everything will be in sync within a few seconds.

Method	Path	Produces
GET	/agent/service/:service_id	application/json

The table below shows this endpoint's support for blocking queries, consistency modes, agent caching, and required ACLs.

Blocking Queries	Consistency Modes	Agent Caching	ACL Required
YES1	none	none	service:read

¹ Supports hash-based blocking only.

Parameters

• service_id (string: <required>) - Specifies the ID of the service to fetch. This is specified as part of the URL.

Sample Request

$ curl \
    http://127.0.0.1:8500/v1/agent/service/web-sidecar-proxy

Sample Response

{
    "Kind": "connect-proxy",
    "ID": "web-sidecar-proxy",
    "Service": "web-sidecar-proxy",
    "Tags": null,
    "Meta": null,
    "Port": 18080,
    "Address": "",
    "Weights": {
        "Passing": 1,
        "Warning": 1
    },
    "EnableTagOverride": false,
    "ContentHash": "4ecd29c7bc647ca8",
    "Proxy": {
        "DestinationServiceName": "web",
        "DestinationServiceID": "web",
        "LocalServiceAddress": "127.0.0.1",
        "LocalServicePort": 8080,
        "Config": {
            "foo": "bar"
        },
        "Upstreams": [
            {
                "DestinationType": "service",
                "DestinationName": "db",
                "LocalBindPort": 9191
            }
        ]
    }
}

The response has the same structure as the service definition with one extra field ContentHash which contains the hash-based blocking query hash for the result. The same hash is also present in X-Consul-ContentHash.

Get local service health

Retrieve an aggregated state of service(s) on the local agent by name.

This endpoints support JSON format and text/plain formats, JSON being the default. In order to get the text format, you can append ?format=text to the URL or use Mime Content negotiation by specifying a HTTP Header Accept starting with text/plain.

Method	Path	Produces
GET	/v1/agent/health/service/name/:service_name	application/json
GET	/v1/agent/health/service/name/:service_name?format=text	text/plain

The table below shows this endpoint's support for blocking queries, consistency modes, agent caching, and required ACLs.

Blocking Queries	Consistency Modes	Agent Caching	ACL Required
NO	none	none	service:read

Those endpoints return the aggregated values of all healthchecks for the service instance(s) and will return the corresponding HTTP codes:

Result	Meaning
200	All healthchecks of every matching service instance are passing
400	Bad parameter (missing service name of id)
404	No such service id or name
429	Some healthchecks are passing, at least one is warning
503	At least one of the healthchecks is critical

Those endpoints might be usefull for the following use-cases:

• a load-balancer wants to check IP connectivity with an agent and retrieve the aggregated status of given service
• create aliases for a given service (thus, the healthcheck of alias uses http://localhost:8500/v1/agent/service/id/aliased_service_id healthcheck)

Note

If you know the ID of service you want to target, it is recommended to use /v1/agent/health/service/id/:service_id so you have the result for the service only. When requesting /v1/agent/health/service/name/:service_name, the caller will receive the worst state of all services having the given name.

Sample Requests

Given 2 services with name web, with web2 critical and web1 passing:

List worst statuses of all instances of web-demo services (HTTP 503)

By Name, Text

curl http://localhost:8500/v1/agent/health/service/name/web?format=text
critical

By Name, JSON

In JSON, the detail of passing/warning/critical services is present in output, in a array.

curl localhost:8500/v1/agent/health/service/name/web

{
    "critical": [
        {
            "ID": "web2",
            "Service": "web",
            "Tags": [
                "rails"
            ],
            "Address": "",
            "Meta": null,
            "Port": 80,
            "EnableTagOverride": false,
            "ProxyDestination": "",
            "Connect": {
                "Native": false,
                "Proxy": null
            },
            "CreateIndex": 0,
            "ModifyIndex": 0
        }
    ],
    "passing": [
        {
            "ID": "web1",
            "Service": "web",
            "Tags": [
                "rails"
            ],
            "Address": "",
            "Meta": null,
            "Port": 80,
            "EnableTagOverride": false,
            "ProxyDestination": "",
            "Connect": {
                "Native": false,
                "Proxy": null
            },
            "CreateIndex": 0,
            "ModifyIndex": 0
        }
    ]
}

List status of web2 (HTTP 503)

Failure By ID, Text

curl http://localhost:8500/v1/agent/health/service/id/web2?format=text
critical

Failure By ID, JSON

In JSON, the output per ID is not an array, but only contains the value of service.

curl localhost:8500/v1/agent/health/service/id/web2

{
    "critical": {
        "ID": "web2",
        "Service": "web",
        "Tags": [
            "rails"
        ],
        "Address": "",
        "Meta": null,
        "Port": 80,
        "EnableTagOverride": false,
        "ProxyDestination": "",
        "Connect": {
            "Native": false,
            "Proxy": null
        },
        "CreateIndex": 0,
        "ModifyIndex": 0
    }
}

List status of web2 (HTTP 200)

Success By ID, Text

curl localhost:8500/v1/agent/health/service/id/web1?format=text
passing

Success By ID, JSON

curl localhost:8500/v1/agent/health/service/id/web1

{
    "passing": {
        "ID": "web1",
        "Service": "web",
        "Tags": [
            "rails"
        ],
        "Address": "",
        "Meta": null,
        "Port": 80,
        "EnableTagOverride": false,
        "ProxyDestination": "",
        "Connect": {
            "Native": false,
            "Proxy": null
        },
        "CreateIndex": 0,
        "ModifyIndex": 0
    }
}

Get local service health by its ID

Retrive an aggregated state of service(s) on the local agent by ID.

See:

Method	Path	Produces
GET	/v1/agent/health/service/id/:service_id	application/json
GET	/v1/agent/health/service/id/:service_id?format=text	text/plain

Parameters and response format are the same as /v1/agent/health/service/name/:service_name.

Register Service

This endpoint adds a new service, with an optional health check, to the local agent.

The agent is responsible for managing the status of its local services, and for sending updates about its local services to the servers to keep the global catalog in sync.

For "connect-proxy" kind services, the service:write ACL for the Proxy.DestinationServiceName value is also required to register the service.

Method	Path	Produces
PUT	/agent/service/register	application/json

The table below shows this endpoint's support for blocking queries, consistency modes, agent caching, and required ACLs.

Blocking Queries	Consistency Modes	Agent Caching	ACL Required
NO	none	none	service:write

Parameters

Note that this endpoint, unlike most also supports snake_case service definition keys for compatibility with the config file format.

• Name (string: <required>) - Specifies the logical name of the service. Many service instances may share the same logical service name.

• ID (string: "") - Specifies a unique ID for this service. This must be unique per agent. This defaults to the Name parameter if not provided.

• Tags (array<string>: nil) - Specifies a list of tags to assign to the service. These tags can be used for later filtering and are exposed via the APIs.

• Address (string: "") - Specifies the address of the service. If not provided, the agent's address is used as the address for the service during DNS queries.

• Meta (map<string|string>: nil) - Specifies arbitrary KV metadata linked to the service instance.

• Port (int: 0) - Specifies the port of the service.

• Kind (string: "") - The kind of service. Defaults to "" which is a typical Consul service. This value may also be "connect-proxy" for services that are Connect-capable proxies representing another service.

• ProxyDestination (string: "") - Deprecated From 1.2.0 to 1.2.3 this was used for "connect-proxy" Kind services however the equivalent field is now in Proxy.DestinationServiceName. Registrations using this field will continue to work until some later major version where this will be removed entirely. It's strongly recommended to switch to using the new field.

• Proxy (Proxy: nil) - From 1.2.3 on, specifies the configuration for a Connect proxy instance. This is only valid if Kind == "connect-proxy". See the Proxy documentation for full details.

• Connect (Connect: nil) - Specifies the configuration for Connect. See the Connect Structure section below for supported fields.

• Check (Check: nil) - Specifies a check. Please see the check documentation for more information about the accepted fields. If you don't provide a name or id for the check then they will be generated. To provide a custom id and/or name set the CheckID and/or Name field.

• Checks (array<Check>: nil) - Specifies a list of checks. Please see the check documentation for more information about the accepted fields. If you don't provide a name or id for the check then they will be generated. To provide a custom id and/or name set the CheckID and/or Name field. The automatically generated Name and CheckID depend on the position of the check within the array, so even though the behavior is deterministic, it is recommended for all checks to either let consul set the CheckID by leaving the field empty/omitting it or to provide a unique value.

• EnableTagOverride (bool: false) - Specifies to disable the anti-entropy feature for this service's tags. If EnableTagOverride is set to true then external agents can update this service in the catalog and modify the tags. Subsequent local sync operations by this agent will ignore the updated tags. For instance, if an external agent modified both the tags and the port for this service and EnableTagOverride was set to true then after the next sync cycle the service's port would revert to the original value but the tags would maintain the updated value. As a counter example, if an external agent modified both the tags and port for this service and EnableTagOverride was set to false then after the next sync cycle the service's port and the tags would revert to the original value and all modifications would be lost.

• Weights (Weights: nil) - Specifies weights for the service. Please see the service documentation for more information about weights. If this field is not provided weights will default to {"Passing": 1, "Warning": 1}.

  It is important to note that this applies only to the locally registered service. If you have multiple nodes all registering the same service their EnableTagOverride configuration and all other service configuration items are independent of one another. Updating the tags for the service registered on one node is independent of the same service (by name) registered on another node. If EnableTagOverride is not specified the default value is false. See anti-entropy syncs for more info.

Connect Structure

For the Connect field, the parameters are:

• Native (bool: false) - Specifies whether this service supports the Connect protocol natively. If this is true, then Connect proxies, DNS queries, etc. will be able to service discover this service.
• Proxy (Proxy: nil) - Deprecated Specifies that a managed Connect proxy should be started for this service instance, and optionally provides configuration for the proxy. The format is as documented in Managed Proxy Deprecation.
• SidecarService (ServiceDefinition: nil) - Specifies an optional nested service definition to register. For more information see Sidecar Service Registration.

Sample Payload

{
  "ID": "redis1",
  "Name": "redis",
  "Tags": [
    "primary",
    "v1"
  ],
  "Address": "127.0.0.1",
  "Port": 8000,
  "Meta": {
    "redis_version": "4.0"
  },
  "EnableTagOverride": false,
  "Check": {
    "DeregisterCriticalServiceAfter": "90m",
    "Args": ["/usr/local/bin/check_redis.py"],
    "HTTP": "http://localhost:5000/health",
    "Interval": "10s",
    "TTL": "15s"
  },
  "Weights": {
    "Passing": 10,
    "Warning": 1
  }
}

Sample Request

$ curl \
    --request PUT \
    --data @payload.json \
    http://127.0.0.1:8500/v1/agent/service/register

Deregister Service

This endpoint removes a service from the local agent. If the service does not exist, no action is taken.

The agent will take care of deregistering the service with the catalog. If there is an associated check, that is also deregistered.

Method	Path	Produces
PUT	/agent/service/deregister/:service_id	application/json

The table below shows this endpoint's support for blocking queries, consistency modes, agent caching, and required ACLs.

Blocking Queries	Consistency Modes	Agent Caching	ACL Required
NO	none	none	service:write

Parameters

• service_id (string: <required>) - Specifies the ID of the service to deregister. This is specified as part of the URL.

Sample Request

$ curl \
    --request PUT \
    http://127.0.0.1:8500/v1/agent/service/deregister/my-service-id

Enable Maintenance Mode

This endpoint places a given service into "maintenance mode". During maintenance mode, the service will be marked as unavailable and will not be present in DNS or API queries. This API call is idempotent. Maintenance mode is persistent and will be automatically restored on agent restart.

Method	Path	Produces
PUT	/agent/service/maintenance/:service_id	application/json

The table below shows this endpoint's support for blocking queries, consistency modes, agent caching, and required ACLs.

Blocking Queries	Consistency Modes	Agent Caching	ACL Required
NO	none	none	service:write

Parameters

• service_id (string: <required>) - Specifies the ID of the service to put in maintenance mode. This is specified as part of the URL.

• enable (bool: <required>) - Specifies whether to enable or disable maintenance mode. This is specified as part of the URL as a query string parameter.

• reason (string: "") - Specifies a text string explaining the reason for placing the node into maintenance mode. This is simply to aid human operators. If no reason is provided, a default value will be used instead. This is specified as part of the URL as a query string parameter, and, as such, must be URI-encoded.

Sample Request

$ curl \
    --request PUT \
    http://127.0.0.1:8500/v1/agent/service/maintenance/my-service-id?enable=true&reason=For+the+docs