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二郎boss_db你好世界?

rebar erlang-otp erlang orm postgresql

skanatek · 技术社区 · 12 年前

最近我尝试安装并运行的演示 boss_db ORM代表Erlang。

以下是我所做的:

克隆存储库
cd boss_db/
rebar get-deps
将一个简单的mydb.erl文件放入 src/ 以下为:
```
-module(mydb).

-compile(export_all).

start() ->
```
DBOptions=[{adapter,pgsql}, {db_host,“localhost”}, {db_port,5432}, {db_username,“postgres”}, {db_password,“mypass”},
{cache_enable,false}, {cache_exp_time,0}],

boss_db:start(数据库选项)。
rebar compile
cd ebin/
跑 erl
mydb:start()

以下是我得到的:

** exception exit: shutdown

我在这里做错了什么?它应该如何运行?

附言:我也试着运行application:start(boss_db),但结果是一样的。

附言:我已阅读 documentation 两次,但我仍然不知道如何处理整个事情。

2 回复 | 直到 12 年前

cashmere Vinod 12 年前

您没有向代码路径添加依赖项。这就是为什么在找不到异常时抛出异常的原因。不要对ebin和erl进行cd。改为运行

erl -pa ebin -pa deps/*/ebin

来自当前目录。

顺便说一句,这不是做这种事情的好方法。相反,使用钢筋创建一个新的空应用程序。在rebar.config中添加boss_db作为应用程序的依赖项。将您自己的源文件放在src下。然后

rebar get-deps compile
erl -pa ebin -pa deps/*/ebin

spfoos 12 年前

git clone git://github.com/evanmiller/boss_db.git
cd boss_db/
rebar get-deps
emacs src/mydb.erl
rebar compile
erl -pa ./ebin ./deps/*/ebin

这些步骤对我很有效。 code:is_loaded() 运行erl后将无法正常工作。只有在调用模块时,才会加载代码。

我确实关闭了应用程序,但这是因为 该代码试图连接到Postgres数据库,但无法连接到它 。

Erlang R15B02 (erts-5.9.2) [source] [smp:8:8] [async-threads:0] [hipe] [kernel-poll:false]

Eshell V5.9.2  (abort with ^G)
1> mydb:start().
** exception exit: shutdown
=ERROR REPORT==== 9-Oct-2012::12:13:07 ===
** Generic server <0.35.0> terminating 
** Last message in was {'EXIT',<0.34.0>,
                        {{badmatch,
                          {error,
                           {{badmatch,
                             {error,
                              {{badmatch,{error,econnrefused}},
                               [{pgsql_sock,init,1,
                                 [{file,"src/pgsql_sock.erl"},{line,51}]},
                                {gen_server,init_it,6,
                                 [{file,"gen_server.erl"},{line,304}]},
                                {proc_lib,init_p_do_apply,3,
                                 [{file,"proc_lib.erl"},{line,227}]}]}}},
                            [{boss_db_controller,init,1,
                              [{file,"src/boss_db_controller.erl"},{line,31}]},
                             {gen_server,init_it,6,
                              [{file,"gen_server.erl"},{line,304}]},
                             {proc_lib,init_p_do_apply,3,
                              [{file,"proc_lib.erl"},{line,227}]}]}}},
                         [{poolboy,new_worker,2,
                           [{file,"src/poolboy.erl"},{line,348}]},
                          {poolboy,prepopulate,4,
                           [{file,"src/poolboy.erl"},{line,370}]},
                          {poolboy,init,2,
                           [{file,"src/poolboy.erl"},{line,74}]},
                          {gen_fsm,init_it,6,
                           [{file,"gen_fsm.erl"},{line,361}]},
                          {proc_lib,init_p_do_apply,3,
                           [{file,"proc_lib.erl"},{line,227}]}]}}
** When Server state == {state,
                            {<0.35.0>,poolboy_sup},
                            simple_one_for_one,
                            [{child,undefined,boss_db_controller,
                                 {boss_db_controller,start_link,
                                     [[{size,5},
                                       {max_overflow,10},
                                       {adapter,pgsql},
                                       {db_host,"localhost"},
                                       {db_port,5432},
                                       {db_username,"postgres"},
                                       {db_password,"mypass"},
                                       {cache_enable,false},
                                       {cache_exp_time,0}]]},
                                 temporary,brutal_kill,worker,
                                 [boss_db_controller]}],
                            {set,0,16,16,8,80,48,
                                {[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],
                                 []},
                                {{[],[],[],[],[],[],[],[],[],[],[],[],[],[],
                                  [],[]}}},
                            0,1,[],poolboy_sup,
                            {boss_db_controller,
                                [{size,5},
                                 {max_overflow,10},
                                 {adapter,pgsql},
                                 {db_host,"localhost"},
                                 {db_port,5432},
                                 {db_username,"postgres"},
                                 {db_password,"mypass"},
                                 {cache_enable,false},
                                 {cache_exp_time,0}]}}
** Reason for termination == 
** {{badmatch,
        {error,
            {{badmatch,
                 {error,
                     {{badmatch,{error,econnrefused}},
                      [{pgsql_sock,init,1,
                           [{file,"src/pgsql_sock.erl"},{line,51}]},
                       {gen_server,init_it,6,
                           [{file,"gen_server.erl"},{line,304}]},
                       {proc_lib,init_p_do_apply,3,
                           [{file,"proc_lib.erl"},{line,227}]}]}}},
             [{boss_db_controller,init,1,
                  [{file,"src/boss_db_controller.erl"},{line,31}]},
              {gen_server,init_it,6,[{file,"gen_server.erl"},{line,304}]},
              {proc_lib,init_p_do_apply,3,
                  [{file,"proc_lib.erl"},{line,227}]}]}}},
    [{poolboy,new_worker,2,[{file,"src/poolboy.erl"},{line,348}]},
     {poolboy,prepopulate,4,[{file,"src/poolboy.erl"},{line,370}]},
     {poolboy,init,2,[{file,"src/poolboy.erl"},{line,74}]},
     {gen_fsm,init_it,6,[{file,"gen_fsm.erl"},{line,361}]},
     {proc_lib,init_p_do_apply,3,[{file,"proc_lib.erl"},{line,227}]}]}