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The authoritative reference for the list of ACTIONs is on GitHub, https://github.com/GEANT/CAT/blob/release_2_0v2.2.1/web/lib/admin/API.php : the class constants API::ACTION_* are the available strings to put into the JSON ACTION field.
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The authoritative reference for the list of PARAMETERs is on GitHub, https://github.com/GEANT/CAT/blob/release_2_0v2.2.1/web/lib/admin/API.php : the class constant API::ACTIONS contains two sets of parameters each, "REQ" = required parameters, "OPT" = optional parameters,
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If the parameter is the integer representation of an EAP type, you can look up the number to use in the source (const INTEGER_...).
List of result codes
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The authoritative reference for the list of error codes is on GitHub, https://github.com/GEANT/CAT/blob/release_2_0v2.2.1/web/lib/admin/API.php : the class constants API::ERROR_*
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