Correctly execute couchbeam_view:fetch/3

[0xAX]

Hello @benoitc,

Sorry if it wrong place for this issues, actually i don't know is it couchbeam issues, couchdb issue or it's my hand.

In fact i tried to fetch some data from CouchDB with CouchBeam. I'm using CouchDB-1.2.0 and CouchBeam d66706641a36b68507e38c844e1714f8d96d4e2a.

I have following view:

{
   "_id": "_design/task",
   "_rev": "5-c8cf44664bd02d170e3fb5bdfef1f35c",
   "language": "erlang",
   "views": {
       "by_task_creation": {
           "map": "fun({Doc}) ->\n\tcase couch_util:get_value(<<\"_id\">>, Doc, null) of\n\t    TaskId = <<\"task:\", _/binary>> ->\n\t\tcase couch_util:get_value(<<\"created\">>, Doc, null) of\n\t\t    null -> ok;\n\t\t    Created -> Emit(Created, null)\n\t\tend;\n\t    _ -> ok\n\tend\nend.\n",
           "reduce": "fun(_Keys, Values, false) -> 0;\n   (_Keys, Values, true)  -> 0 end.\n"
       },
       "by_task_selector": {
           "map": "fun({Doc}) ->\n\tcase couch_util:get_value(<<\"_id\">>, Doc, null) of\n\t    TaskId = <<\"task:\", _/binary>> ->\n\t\tcase couch_util:get_value(<<\"selector\">>, Doc, null) of\n\t\t    null -> ok;\n\t\t    Selector -> Emit(Selector, TaskId)\n\t\tend;\n\t    _ -> ok\n\tend\nend.\n"
       }
   }
}

Than i successfully connect to the database, and try to fetch data and reduce with:

couchbeam_view:fetch(DB, {<<"_design/task">>, <<"by_task_creation">>}, [{reduce, true}]).

But got error there:

Reason: {case_clause,{error,[],function_clause}}

I tried to request it with curl:

http://localhost:5984/xray/_design/task/_view/by_task_creation/?reduce=true

And it works, it returns:

{"rows":[]}

Maybe reduce crashes from the fact that there are no rows in the database?...

Thank you.

[benoitc]

can you provide the full trace?

[0xAX]

Log from /var/log/couchdb/couch.log:

[Thu, 27 Jun 2013 13:44:31 GMT] [info] [<0.195.0>] 127.0.0.1 - - GET / 200
[Thu, 27 Jun 2013 13:44:44 GMT] [error] [emulator] Error in process <0.266.0> with exit value: {{nocatch,{'EXIT',{{badmatch,[]},[{couch_query_servers,new_process,3,[{file,"couch_query_servers.erl"},{line,472}]},{couch_query_servers,lang_proc,3,[{file,"couch_query_servers.erl"},{line,462}]},{couch_query_servers,handle_call... 

[Thu, 27 Jun 2013 13:44:44 GMT] [error] [<0.258.0>] ** Generic server <0.258.0> terminating 
** Last message in was {'EXIT',<0.263.0>,
                        {{nocatch,
                          {'EXIT',
                           {{badmatch,[]},
                            [{couch_query_servers,new_process,3,
                              [{file,"couch_query_servers.erl"},{line,472}]},
                             {couch_query_servers,lang_proc,3,
                              [{file,"couch_query_servers.erl"},{line,462}]},
                             {couch_query_servers,handle_call,3,
                              [{file,"couch_query_servers.erl"},{line,334}]},
                             {gen_server,handle_msg,5,
                              [{file,"gen_server.erl"},{line,588}]},
                             {proc_lib,init_p_do_apply,3,
                              [{file,"proc_lib.erl"},{line,227}]}]}}},
                         [{couch_query_servers,get_os_process,1,
                           [{file,"couch_query_servers.erl"},{line,578}]},
                          {couch_query_servers,start_doc_map,3,
                           [{file,"couch_query_servers.erl"},{line,53}]},
                          {couch_view_updater,add_query_server,1,
                           [{file,"couch_view_updater.erl"},{line,102}]},
                          {couch_view_updater,'-update/3-fun-0-',3,
                           [{file,"couch_view_updater.erl"},{line,53}]}]}}
** When Server state == {group_state,undefined,<<"xray">>,
                         {"/var/lib/couchdb/1.2.0",<<"xray">>,
                          {group,
                           <<108,94,176,19,82,97,218,194,32,155,210,91,181,126,
                             18,123>>,
                           nil,<<"_design/task">>,<<"erlang">>,[],
                           [{view,0,0,0,[],
                             <<"fun({Doc}) ->\n\tcase couch_util:get_value(<<\"_id\">>, Doc, null) of\n\t    TaskId = <<\"task:\", _/binary>> ->\n\t\tcase couch_util:get_value(<<\"created\">>, Doc, null) of\n\t\t    null -> ok;\n\t\t    Created -> Emit(Created, null)\n\t\tend;\n\t    _ -> ok\n\tend\nend.\n">>,
                             nil,
                             [{<<"by_task_creation">>,
                               <<"fun(_Keys, Values, false) -> length(Values);\n   (_Keys, Values, true)  -> lists:sum(Values) end.\n">>}],
                             []},
                            {view,1,0,0,
                             [<<"by_task_selector">>],
                             <<"fun({Doc}) ->\n\tcase couch_util:get_value(<<\"_id\">>, Doc, null) of\n\t    TaskId = <<\"task:\", _/binary>> ->\n\t\tcase couch_util:get_value(<<\"selector\">>, Doc, null) of\n\t\t    null -> ok;\n\t\t    Selector -> Emit(Selector, TaskId)\n\t\tend;\n\t    _ -> ok\n\tend\nend.\n">>,
                             nil,[],[]}],
                           {[]},
                           nil,0,0,nil,nil}},
                         {group,
                          <<108,94,176,19,82,97,218,194,32,155,210,91,181,126,
                            18,123>>,
                          <0.260.0>,<<"_design/task">>,<<"erlang">>,[],
                          [{view,0,0,0,[],
                            <<"fun({Doc}) ->\n\tcase couch_util:get_value(<<\"_id\">>, Doc, null) of\n\t    TaskId = <<\"task:\", _/binary>> ->\n\t\tcase couch_util:get_value(<<\"created\">>, Doc, null) of\n\t\t    null -> ok;\n\t\t    Created -> Emit(Created, null)\n\t\tend;\n\t    _ -> ok\n\tend\nend.\n">>,
                            {btree,<0.260.0>,nil,
                             #Fun<couch_btree.3.133731799>,
                             #Fun<couch_btree.4.133731799>,
                             #Fun<couch_view.less_json_ids.2>,
                             #Fun<couch_view_group.10.75991388>,snappy},
                            [{<<"by_task_creation">>,
                              <<"fun(_Keys, Values, false) -> length(Values);\n   (_Keys, Values, true)  -> lists:sum(Values) end.\n">>}],
                            []},
                           {view,1,0,0,
                            [<<"by_task_selector">>],
                            <<"fun({Doc}) ->\n\tcase couch_util:get_value(<<\"_id\">>, Doc, null) of\n\t    TaskId = <<\"task:\", _/binary>> ->\n\t\tcase couch_util:get_value(<<\"selector\">>, Doc, null) of\n\t\t    null -> ok;\n\t\t    Selector -> Emit(Selector, TaskId)\n\t\tend;\n\t    _ -> ok\n\tend\nend.\n">>,
                            {btree,<0.260.0>,nil,
                             #Fun<couch_btree.3.133731799>,
                             #Fun<couch_btree.4.133731799>,
                             #Fun<couch_view.less_json_ids.2>,
                             #Fun<couch_view_group.10.75991388>,snappy},
                            [],[]}],
                          {[]},
                          {btree,<0.260.0>,nil,#Fun<couch_btree.3.133731799>,
                           #Fun<couch_btree.4.133731799>,
                           #Fun<couch_btree.5.133731799>,nil,snappy},
                          0,0,nil,nil},
                         <0.263.0>,nil,false,
                         [{{<0.218.0>,#Ref<0.0.0.1788>},2}],
                         <0.262.0>,false}
** Reason for termination == 
** {'EXIT',{{badmatch,[]},
            [{couch_query_servers,new_process,3,
                                  [{file,"couch_query_servers.erl"},
                                   {line,472}]},
             {couch_query_servers,lang_proc,3,
                                  [{file,"couch_query_servers.erl"},
                                   {line,462}]},
             {couch_query_servers,handle_call,3,
                                  [{file,"couch_query_servers.erl"},
                                   {line,334}]},
             {gen_server,handle_msg,5,[{file,"gen_server.erl"},{line,588}]},
             {proc_lib,init_p_do_apply,3,
                       [{file,"proc_lib.erl"},{line,227}]}]}}

[Thu, 27 Jun 2013 13:44:44 GMT] [error] [<0.258.0>] {error_report,<0.31.0>,
                     {<0.258.0>,crash_report,
                      [[{initial_call,{couch_view_group,init,['Argument__1']}},
                        {pid,<0.258.0>},
                        {registered_name,[]},
                        {error_info,
                         {exit,
                          {'EXIT',
                           {{badmatch,[]},
                            [{couch_query_servers,new_process,3,
                              [{file,"couch_query_servers.erl"},{line,472}]},
                             {couch_query_servers,lang_proc,3,
                              [{file,"couch_query_servers.erl"},{line,462}]},
                             {couch_query_servers,handle_call,3,
                              [{file,"couch_query_servers.erl"},{line,334}]},
                             {gen_server,handle_msg,5,
                              [{file,"gen_server.erl"},{line,588}]},
                             {proc_lib,init_p_do_apply,3,
                              [{file,"proc_lib.erl"},{line,227}]}]}},
                          [{gen_server,terminate,6,
                            [{file,"gen_server.erl"},{line,747}]},
                           {proc_lib,init_p_do_apply,3,
                            [{file,"proc_lib.erl"},{line,227}]}]}},
                        {ancestors,[<0.257.0>]},
                        {messages,[]},
                        {links,[<0.260.0>,<0.128.0>]},
                        {dictionary,[]},
                        {trap_exit,true},
                        {status,running},
                        {heap_size,1597},
                        {stack_size,24},
                        {reductions,546}],
                       []]}}
[Thu, 27 Jun 2013 13:44:44 GMT] [error] [<0.218.0>] Uncaught server error: {'EXIT',
                                            {{badmatch,[]},
                                             [{couch_query_servers,
                                               new_process,3,
                                               [{file,
                                                 "couch_query_servers.erl"},
                                                {line,472}]},
                                              {couch_query_servers,lang_proc,
                                               3,
                                               [{file,
                                                 "couch_query_servers.erl"},
                                                {line,462}]},
                                              {couch_query_servers,
                                               handle_call,3,
                                               [{file,
                                                 "couch_query_servers.erl"},
                                                {line,334}]},
                                              {gen_server,handle_msg,5,
                                               [{file,"gen_server.erl"},
                                                {line,588}]},
                                              {proc_lib,init_p_do_apply,3,
                                               [{file,"proc_lib.erl"},
                                                {line,227}]}]}}
[Thu, 27 Jun 2013 13:44:44 GMT] [error] [<0.260.0>] ** Generic server <0.260.0> terminating 
** Last message in was {'EXIT',<0.258.0>,
                           {'EXIT',
                               {{badmatch,[]},
                                [{couch_query_servers,new_process,3,
                                     [{file,"couch_query_servers.erl"},
                                      {line,472}]},
                                 {couch_query_servers,lang_proc,3,
                                     [{file,"couch_query_servers.erl"},
                                      {line,462}]},
                                 {couch_query_servers,handle_call,3,
                                     [{file,"couch_query_servers.erl"},
                                      {line,334}]},
                                 {gen_server,handle_msg,5,
                                     [{file,"gen_server.erl"},{line,588}]},
                                 {proc_lib,init_p_do_apply,3,
                                     [{file,"proc_lib.erl"},{line,227}]}]}}}
** When Server state == {file,{file_descriptor,prim_file,{#Port<0.2665>,25}},
                              51}
** Reason for termination == 
** {'EXIT',{{badmatch,[]},
            [{couch_query_servers,new_process,3,
                                  [{file,"couch_query_servers.erl"},
                                   {line,472}]},
             {couch_query_servers,lang_proc,3,
                                  [{file,"couch_query_servers.erl"},
                                   {line,462}]},
             {couch_query_servers,handle_call,3,
                                  [{file,"couch_query_servers.erl"},
                                   {line,334}]},
             {gen_server,handle_msg,5,[{file,"gen_server.erl"},{line,588}]},
             {proc_lib,init_p_do_apply,3,
                       [{file,"proc_lib.erl"},{line,227}]}]}}

[Thu, 27 Jun 2013 13:44:44 GMT] [error] [<0.260.0>] {error_report,<0.31.0>,
                     {<0.260.0>,crash_report,
                      [[{initial_call,{couch_file,init,['Argument__1']}},
                        {pid,<0.260.0>},
                        {registered_name,[]},
                        {error_info,
                         {exit,
                          {'EXIT',
                           {{badmatch,[]},
                            [{couch_query_servers,new_process,3,
                              [{file,"couch_query_servers.erl"},{line,472}]},
                             {couch_query_servers,lang_proc,3,
                              [{file,"couch_query_servers.erl"},{line,462}]},
                             {couch_query_servers,handle_call,3,
                              [{file,"couch_query_servers.erl"},{line,334}]},
                             {gen_server,handle_msg,5,
                              [{file,"gen_server.erl"},{line,588}]},
                             {proc_lib,init_p_do_apply,3,
                              [{file,"proc_lib.erl"},{line,227}]}]}},
                          [{gen_server,terminate,6,
                            [{file,"gen_server.erl"},{line,747}]},
                           {proc_lib,init_p_do_apply,3,
                            [{file,"proc_lib.erl"},{line,227}]}]}},
                        {ancestors,[<0.258.0>,<0.257.0>]},
                        {messages,[{'EXIT',<0.262.0>,shutdown}]},
                        {links,[]},
                        {dictionary,[]},
                        {trap_exit,true},
                        {status,running},
                        {heap_size,1597},
                        {stack_size,24},
                        {reductions,1530}],
                       []]}}
[Thu, 27 Jun 2013 13:44:44 GMT] [info] [<0.218.0>] 127.0.0.1 - - GET /xray/_design/task/_view/by_task_creation?reduce=true 500
[Thu, 27 Jun 2013 14:06:19 GMT] [info] [<0.197.0>] 127.0.0.1 - - POST /basic 404

[benoitc]

I don't see the function_clause error, I guess this one is happening in couchbeam then. I'm on it.

[benoitc]

should be fixed in 21c44d50f893f4e18f1a33bc89c260e40c4ff85f let me know.

[0xAX]

Today I alredy can't check it, but tomorrow morning i'll let you know, many thanks

[0xAX]

@benoitc i tried many different versions of couchbeam from different repositories and this https://github.com/travelping/couchbeam/tree/tp-integration not crash for my example.

[benoitc]

Is the current master working for you? What is your current error?

[benoitc]

note that tests are passing:

https://github.com/benoitc/couchbeam/blob/master/t/005-view.t#L106

[0xAX]

@benoitc i think i had the same error with current master, In monday i will have my working machine and i'll test with current master yet another time and let you know about results.

[benoitc]

I just show that in your code you have reduce=false but tested reduce=true in your code, does it gave the same result? What is the full trace in the application using couchbeam?

[0xAX]

sorry, i missunderstood, i have error with {reduce, true} and if i remove it all works

[benoitc]

@0xAX I will add a test over the we, and will see what happen. Thanks for the feedback :)

[0xAX]

Hello @benoitc i tested it, and now it works with master. Thank you.

[benoitc]

@0xAX thanks for the feedback, closing the issue now :)