retry connection in couchbeam_uuids

[benoitc]

When the couchbeam attempts to get a UUIDS using a closed socket it get the following error:

=ERROR REPORT==== 9-Dec-2014::00:29:35 ===
** Generic server couchbeam_uuids terminating 
** Last message in was {get_uuids,
                           {server,<<"http://localhost:5984">>,
                               [{connect_timeout,200}]},
                           1}
** When Server state == {state}
** Reason for termination == 
** {{badmatch,{error,closed}},
    [{couchbeam_uuids,do_get_uuids,4,
                      [{file,"src/couchbeam_uuids.erl"},{line,90}]},
     {couchbeam_uuids,handle_call,3,
                      [{file,"src/couchbeam_uuids.erl"},{line,61}]},
     {gen_server,handle_msg,5,[{file,"gen_server.erl"},{line,580}]},
     {proc_lib,init_p_do_apply,3,[{file,"proc_lib.erl"},{line,237}]}]}
** exception exit: {{{badmatch,{error,closed}},
                     [{couchbeam_uuids,do_get_uuids,4,
                                       [{file,"src/couchbeam_uuids.erl"},{line,90}]},
                      {couchbeam_uuids,handle_call,3,
                                       [{file,"src/couchbeam_uuids.erl"},{line,61}]},
                      {gen_server,handle_msg,5,
                                  [{file,"gen_server.erl"},{line,580}]},
                      {proc_lib,init_p_do_apply,3,
                                [{file,"proc_lib.erl"},{line,237}]}]},
                    {gen_server,call,
                                [couchbeam_uuids,
                                 {get_uuids,{server,<<"http://localhost:5984">>,
                                                    [{connect_timeout,200}]},
                                            1}]}}
     in function  gen_server:call/2 (gen_server.erl, line 182)
     in call from couchbeam:save_doc/4 (src/couchbeam.erl, line 563)
     ....

[benoitc]

There is no real reason to connect to couchdb to retrieve UUIDS. instead we should use our own proper module locally so we also remove one extra call.

[kxepal]

Here you the case when it could make a sense: uuids with utc_id algorithm when uuid isn't just an uuid, but just some magic id value. This magic is defined by utc_id_suffix which is server specific and you probably won't embed such into your code. But in overall yes, there are almost no reasons to call /__uuids from client side.

[benoitc]

@kxepal right... Also let's just fix the issue right now, if not it would need a major release.