Service Discovery with etcd (deprecated)

Document updated on Feb 22, 2021

The etcd Service Discovery integration allows you to perform the host resolution using your existing etcd setup.

The integration etcd is controlled by the krakend-etcd component and adds client and subscriber capabilities for etcd.

Enabling etcd

To enable the integration add in the root of your configuration file the necessary settings:

{
  "version": 2,
  "extra_config": {
    "github_com/devopsfaith/krakend-etcd": {
      "machines": [
        "https://192.168.1.100:4001",
        "https://192.168.1.101:4001"
      ],
      "dial_timeout": "5s",
      "dial_keepalive": "30s",
      "header_timeout": "1s",
      "cert": "/path/to/cert",
      "key": "/path/to/cert-private-key",
      "cacert": "/path/to/CA-cert"
    }
  },
  ...

The only mandatory key inside the github_com/devopsfaith/krakend-etcd namespace is machines, so the integration knows where etcd lives. The rest of the keys in the configuration are optional.

The timeouts and keepalive will take the shown values if the keys are missing, and the certificates (cert, key, and cacert) are not needed if you use plain connections.

Now you are able to use etcd with your backends.

Using etcd to resolve backends

Once the integration has been enabled, add the following keys in the backend section of your configuration. The host key can be skipped if there is another host key in the root level of the configuration.

• "sd": "etcd": To set etcd as the service discovery
• "host": []: The list of all the services you want to resolve

For instance, set the service discovery for an individual backend:

...
"backend": [
        {
          "url_pattern": "/foo",
          "sd": "etcd",
          "host": [
            "api-catalog"
          ],
          "disable_host_sanitize": true
        }
      ]
...