sf_transform 使用指南

2022.07.07 更新

非常感谢 @haoxian 的提醒，sf_transform 的解决方案终于可以落幕了

有了新的原生解决方案, 仅需要在 rebar.config 的 erl_opts 配置项加入 deterministic 即可：

1
2
3

{erl_opts, [
  deterministic
]}.

亦可以通过环境变量来配置：

1	ERL_COMPILER_OPTIONS="[deterministic]" rebar3 compile

官方文档中 deterministic 的解析如下：

Omit the options and source tuples in the list returned by Module:module_info(compile), and reduce the paths in stack traces to the module name alone. This option will make it easier to achieve reproducible builds.

前言

如果你正在使用rebar3工具来工具你的项目和代码,有可能会很讨厌在shell窗口中的报错部分的文件名,像这样:

1	{file,"/home/xxx/work/erlang/test/tsf/src/tsf_sup.erl"}

特别是当文件夹路径很深 or 堆栈很多，你可能会看到满屏都是路径
那该如何去解决呢？

可能你的shell窗口显示的是这样:

17:09:28.275 [error] CRASH REPORT Process <0.227.0> with 0 neighbours exited with reason: {{test,[{tsf_sup,init,1,[{file,"/home/xxx/work/erlang/test/tsf/src/tsf_sup.erl"},{line,35}]},{supervisor,init,1,[{file,"supervisor.erl"},{line,294}]},{gen_server,init_it,6,[{file,"gen_server.erl"},{line,328}]},{proc_lib,init_p_do_apply,3,[{file,"proc_lib.erl"},{line,247}]}]},{tsf_app,start,[normal,[]]}} in application_master:init/4 line 134
17:09:28.275 [info] Application tsf exited with reason: {{test,[{tsf_sup,init,1,[{file,"/home/xxx/work/erlang/test/tsf/src/tsf_sup.erl"},{line,35}]},{supervisor,init,1,[{file,"supervisor.erl"},{line,294}]},{gen_server,init_it,6,[{file,"gen_server.erl"},{line,328}]},{proc_lib,init_p_do_apply,3,[{file,"proc_lib.erl"},{line,247}]}]},{tsf_app,start,[normal,[]]}}

=INFO REPORT==== 2-Mar-2019::17:09:28 ===
    application: lager
    exited: stopped
    type: temporary
===> Failed to boot tsf for reason {{test,
                                                [{tsf_sup,init,1,
                                                  [{file,
                                                    "/home/xxx/work/erlang/test/tsf/src/tsf_sup.erl"},
                                                   {line,35}]},
                                                 {supervisor,init,1,
                                                  [{file,"supervisor.erl"},
                                                   {line,294}]},
                                                 {gen_server,init_it,6,
                                                  [{file,"gen_server.erl"},
                                                   {line,328}]},
                                                 {proc_lib,init_p_do_apply,3,
                                                  [{file,"proc_lib.erl"},
                                                   {line,247}]}]},
                                               {tsf_app,start,[normal,[]]}}

是的,报错的文件名真的是太长了,长到怀疑人生

这是因为rebar3的和erl的编译机制造成的,曾相关修改rebar3的编译部分,但是考虑到不一定全部人都会有这个需要,因此便通过元编程的方法,去除文件名的路径部分,只保留文件名

用法

只需要将以下部分代码增加到你的 rebar.config文件中:

{overrides, [
    %% For all apps:
    {add, [
        {deps, [sf_transform]},
        {erl_opts, [{sf_type, basename}, {parse_transform, sf_transform}]}
    ]},
    %% Or for just one app:
    {del, parse_trans, [
        {deps, [sf_transform]},
        {erl_opts, [{sf_type, basename}, {parse_transform, sf_transform}]}
    ]},
    {del, sf_transform, [
        {deps, [sf_transform]},
        {erl_opts, [{sf_type, basename}, {parse_transform, sf_transform}]}
    ]}
]}.

然后,你的世界会变得更加清晰和美好:

17:16:39.427 [error] CRASH REPORT Process <0.535.0> with 0 neighbours exited with reason: test in tsf_sup:init/1 line 35 in gen_server:init_it/6 line 352
17:16:39.427 [error] CRASH REPORT Process <0.533.0> with 0 neighbours exited with reason: {{test,[{tsf_sup,init,1,[{file,"tsf_sup.erl"},{line,35}]},{supervisor,init,1,[{file,"supervisor.erl"},{line,294}]},{gen_server,init_it,6,[{file,"gen_server.erl"},{line,328}]},{proc_lib,init_p_do_apply,3,[{file,"proc_lib.erl"},{line,247}]}]},{tsf_app,start,[normal,[]]}} in application_master:init/4 line 134
17:16:39.427 [info] Application tsf exited with reason: {{test,[{tsf_sup,init,1,[{file,"tsf_sup.erl"},{line,35}]},{supervisor,init,1,[{file,"supervisor.erl"},{line,294}]},{gen_server,init_it,6,[{file,"gen_server.erl"},{line,328}]},{proc_lib,init_p_do_apply,3,[{file,"proc_lib.erl"},{line,247}]}]},{tsf_app,start,[normal,[]]}}


=INFO REPORT==== 2-Mar-2019::17:16:39 ===
    application: compiler
    exited: stopped
    type: temporary
===> Failed to boot tsf for reason {{test,
                                                [{tsf_sup,init,1,
                                                  [{file,"tsf_sup.erl"},
                                                   {line,35}]},
                                                 {supervisor,init,1,
                                                  [{file,"supervisor.erl"},
                                                   {line,294}]},
                                                 {gen_server,init_it,6,
                                                  [{file,"gen_server.erl"},
                                                   {line,328}]},
                                                 {proc_lib,init_p_do_apply,3,
                                                  [{file,"proc_lib.erl"},
                                                   {line,247}]}]},
                                               {tsf_app,start,[normal,[]]}}