Managing health checks

The Appclacks CLI can be used to manage health checks

How health checks are executed

You can choose when you create an health check if it should be executed or not by the Appclacks cloud platform.

It’s possible to create health checks on Appclacks but to host yourself the prober executing the health check, or to execute it by both Appclacks and on your infrastructure. See the Appclacks on your private infrastructure guide for more information about self-hosting.

Health check types

Appclacks supports 4 healthchecks types today:

• HTTP(s): An HTTP request will be executed on the target. You can configure a lot of options about the health check request (method, path, headers, protocol, TLS configuration, body…) or the expected response (status code, body).
• TCP: A TCP connection will be initiated with the target. You can also use this kind of health check to check that a TCP target is not responding, to be sure that a component is not exposed on the internet for example.
• TLS: A TLS connection will be initiated by the target. If you host the prober yourself you can even configure which certificates to use for the connection.
• DNS: A DNS resolution will be executed on a domain. You can use it to see if the resolution is working and to check the IP returned by it.
• Command: An arbitrary command (with optional arguments) will be executed. The health check is considered failed if the command fails to execute.

Creating an health check

Use the appclacks healthcheck <type> create command to create a health check, where <type> is the health check type (http, tcp, tls, dns, command).

In this example, we create an HTTP health check targeting appclacks.com. You can see in the response (in json due to the --output option) the default values for HTTP health checks.

$ appclacks healthcheck http create --name "hello" --target "appclacks.com" --output json

{"id":"caaa5899-26a7-4a91-a77a-86adc849d23e","name":"hello","type":"http","timeout":"5s","interval":"60s","created-at":"2022-12-04T21:47:03.592347391Z","enabled":true,"Definition":{"valid-status":[200],"target":"appclacks.com","method":"GET","port":443,"redirect":true,"protocol":"https"}}

The --disabled flag controls whether or not the health check should be executed by the Appclacks cloud platform. If set, the health check enabled field will be set to false and the health will not be executed by Appclacks.

Use the --help command to get details about health checks, for example appclacks healthcheck http create --help.

Managing health checks

The appclacks healthcheck list and appclacks healthcheck get --id <healthcheck_id> commands can be used to retrieve health checks information.

You can update an existing health check with the appclacks healthcheck <type> update commands. All health checks fields which you want to configure should be specified, the update is a replace.

Health checks results

Each time a health check is executed by the Appclacks cloud platform, its result is stored and available through the Appclacks API.

The appclacks healthcheck result list command retrieves health checks results. By default, all health check results from the last 5 minutes are retrieved. + Health checks results are paginated and only 100 results are returned. The --page option can be used to retrieve the next results from the list.

You can also configure which results you want to retrieve with the flags:

• --healthcheck-id: Get the results for a specific health check only.
• --start-date: The start date (UTC) for retrieving results, in format 2006-01-02T15:04:05.
• --end-date: The end date (UTC) for retrieving results, in the format 2006-01-02T15:04:05.
• --end-date: The end date (UTC) for retrieving results, in the format 2006-01-02T15:04:05.
• --error: Retrieve only failed health checks.
• --success: Retrieve only successful health checks.