CRDT braindump

gistfile1.clj

;; Example repository-format for automatic server-side synching (p2p-web)
;; commutative merging must be possible, it is (almost) a converging and commutative distributed data type(?)
#_{:uuid "blib" ;; used to ensure universal identity on repo creation (cannot conflict)
   :schema {:type "http://github.com/ghubber/geschichte" ;; might not change, if it does warn and drop merge
            :version (max v1 v2)} ;; internal only, allows update to server side synching software
   :public (or p1 p2) ;; might only turn to true, always false initially, allows public access to repo meta-data, no strong safety, all values are still distributed!; if false only read access from user itself allowed; must be true for pull-requests
   :causal-order {12344 #{3774 23} ;; use uuids as commit ids, unionize, no conflicts, removal impossible
                  3774 #{12}
                  23 #{12}
                  12 #{}}
   :branches {"master" #{12344} ;; conflict possible -> each lca + union, >1 marks conflict
              "back75664" #{23}}
   :head "back75664" ;; conflict possible -> use time-stamp as heuristic(!)
   :last-update (max ts1 ts2) ;; not used for critical fields (e.g. synching decisions)
   :pull-requests {"[email protected]" {"master" {:backways {}
                                               :cut #{}}}}} ;; unionized, filtered by value
;; if not in causal-order keys; if empty remove
;; if >1 conflict, try to resolve with lca; should be avoided by applications, if not ask user
;; '[email protected]' is place of remote-metadata, 4588 as head requested, branch-data not transferred