API POST endpoint /rest/addons always returns 200 even with wrong parameters

[crazyelectron-io]

POST-ing to /rest/addons to install a marketplace add-on will always return 200 (OK) with an empty body, no matter what parameters are passed. Also when installing an already installed add-on, it gives the same result.
I would expect a 404 if it gets passed a non-existing add-on.

This is a simple script (rule) I use to install marketplace addons during startup:

rule "InstallMarketAddons" do
  description "Install marketplace add-ons at system start"
  on_start at_level: 80
  delay 20.seconds  # Let OH core do its magic first
  run do
    # Extract the marketplace add-ons line from `conf/services/addons.cfg`
    cfgLines = IO.readlines('{{ openhab_conf_dir }}/services/addons.cfg')
    if lineIndex = cfgLines.index{ |line| line =~ /marketplace/ } then
      logger.info "Install Marketplace addons defined in addons.cfg at system start"
      addons = cfgLines[lineIndex].split('=')[1].strip
      # Loop through each addon
      addons.split(",").each do |addon|
        addonName, addonId = addon.split(":")
        #TODO: Check for ill-formatted entries
        logger.info "Install addon #{addonName} (#{addonId}) from marketplace"
        # Create the HTTP object
        uri = URI.parse("{{ openhab_api_url }}/addons/marketplace:#{addonId}/install?serviceId=marketplace")
        header = {'Content-Type': 'text/plain', 'Accept': '*/*', 'X-OPENHAB-TOKEN': '{{ openhab_api_token }}'}
        http = Net::HTTP.new(uri.host, uri.port)
        request = Net::HTTP::Post.new(uri.request_uri, header)
        request.body = "id=#{addonId}"
        # Send the request
        response = http.request(request)
        # Note: The API always returns 200 with an empty body, so actually no use logging it
        logger.debug "Result #{response.code} (#{response.body}) - installing marketplace addon #{addonName} (#{addonId})"
      end # of loop through each entry
    end # if
  end
end

There are two Ansible variables in the script to specify the base URL of the API endpoint and the token.
The script works by reading a line starting with marketplace= and extracting the add-on id's to install.
By specifying a non-exsitings binding the reported behaviour can be reproduced.

Your Environment

Debian 12.
OpenHAB 4.1.0 using the official OH container image.

[openhab-bot]

This issue has been mentioned on openHAB Community. There might be relevant details there:

https://community.openhab.org/t/solved-install-marketplace-addon-via-rest-api-returns-200-but-nothing-is-installed/152399/7

[J-N-K]

The reason is that the installation is asynchronous. The response is create when the add-on service exists and the command to install has been successfully send. We can probably improve that with an additional check if the service supports that add-on.

[crazyelectron-io]

Thanks for your quick response.
I understand that the installation is asynchronous - like just about everything in an event-driven system like OpenHBA - and there is no callback mechanism to get the actual result. So, to check if an add-on is installed would require a (delayed/retried) GET to /rest/addons/{addend}.

My main point is that it accepts non-existing add-ons and like you said that could be improved. :o)
The documentation states that a 404 can be returned, but it looks like that will never happen with the current implementation.

[crazyelectron-io]

Wow, this gives "quick-fix" a whole new meaning! :o)
Reported, fixed and merged in less than 7 hours...