Methods

The UP-API specifies the usage of the HTTP-methods GET, HEAD, PUT, POST and DELETE as described in RFC-2616. A request may contain a HTTP-body and HTTP-Basic-Authentication-Header. A response contains a HTTP-status and may contain an HTTP-response.  The UP-API specifies JSON as format for HTTP-body resp. HTTP-response.

• GET - fetch data
  no HTTP-body, but all request-data is included in the URL and HTTP-header
• HEAD - check existence of a resource
  similar to GET, but no HTTP-response, only HTTP-status
• POST - create a new entity as a new subordinate
  not idempotent, i.e. if you retry the request N times, you will end up having N different subordinate-URIs (eg. a new message within an article)
• PUT - update an already existing resource or create a new resource
  idempotent, i.e. if you retry the same request multiple times, the result is equivalent to single request
• DELETE - delete an already existing resource

PUT, POST and DELETE always need authentication (using HTTP-Header, see DataPrivacy) whereas it is optional for GET and HEAD. The response of an authenticated GET may contain additionally protected variable/values for authorized users.

The Internet Assigned Numbers Authority (IANA) maintains the official registry of HTTP status codes.

UNITED-PAGES specifies the HTTP status code depending on the following conditions:

+ auth	Basic-HTTP-Authentication successful
- auth	Basic-HTTP-Authentication failed
+ anonymous	Basic-HTTP-Authentication not used
+ unit	URL correct,  UNIT existing
- unit	URL correct,  UNIT not existing
- url	URL-format wrong
+ read	Authentication-username/email member of read-whitlist or write-whitelist or owner of UNIT
- read	Authentication-username/email neither member of read-whitlist nor write-whitelist nor owner of UNIT
+ write	Authentication-username/email member of write-whitelist or owner of UNIT
- write	Authentication-username/email neither member of write-whitelist nor owner of UNIT

UNITED-PAGES specifies for each method the following HTTP status codes: