第三方程序

使用 Websockets 和 Erlang 浏览

$ rebar3 -v
rebar 3.25.1 on Erlang/OTP 28 Erts 16.0.3

$ cd published
$ git clone git@github.com:gnu4cn/bertie.git
正克隆到 'bertie'...
警告：您似乎克隆了一个空仓库。

$ vim README.md
$ git add README.md
$ git commit README.md
$ git push
枚举对象中: 3, 完成.
对象计数中: 100% (3/3), 完成.
写入对象中: 100% (3/3), 240 字节 | 240.00 KiB/s, 完成.
总共 3（差异 0），复用 0（差异 0），包复用 0（来自  0 个包）
To github.com:gnu4cn/bertie.git
 * [new branch]      main -> main

$ cd published
$ rebar3 new release bertie
===> Writing bertie/apps/bertie/src/bertie_app.erl
===> Writing bertie/apps/bertie/src/bertie_sup.erl
===> Writing bertie/apps/bertie/src/bertie.app.src
===> Writing bertie/rebar.config
===> Writing bertie/config/sys.config
===> Writing bertie/config/vm.args
===> Writing bertie/.gitignore
===> Writing bertie/LICENSE.md
===> Writing bertie/README.md

-module(bertie).
-export([start/0]).

start() -> io:format("Hello my name is Bertie~n").

$ tree ~/published/bertie
.
├── apps
│   └── bertie
│       └── src
│           ├── bertie_app.erl
│           ├── bertie.app.src
│           ├── bertie.erl
│           └── bertie_sup.erl
├── _build
│   └── default
│       └── lib
│           └── bertie
│               ├── ebin
│               │   ├── bertie.app
│               │   ├── bertie_app.beam
│               │   ├── bertie.beam
│               │   ├── bertie_sup.beam
│               │   ├── elog4.config
│               ├── include -> ../../../../apps/bertie/include
│               ├── priv -> ../../../../apps/bertie/priv
│               └── src -> ../../../../apps/bertie/src
├── config
│   ├── sys.config
│   └── vm.args
├── LICENSE.md
├── README.md
├── rebar.config
└── rebar.lock

11 directories, 18 files

$ rebar3 compile
===> Verifying dependencies...
===> Analyzing applications...
===> Compiling bertie

$ git add apps/bertie/src
$ git add commit
$ git push

Bertie has been run 10 times

-module(bertie).
-export([start/0]).

start() ->
    Handle = bitcask:open("bertie_database", [read_write]),
    N = fetch(Handle),
    store(Handle, N+1),
    io:format("Bertie has been run ~p times~n", [N]),
    bitcask:close(Handle),
    init:stop().

store(Handle, N) ->
    bitcask:put(Handle, <<"bertie_database">>, term_to_binary(N)).

fetch(Handle) ->
    case bitcask:get(Handle, <<"bertie_database">>) of
        not_found -> 1;
        {ok, Bin} -> binary_to_term(Bin)
    end.

{deps, [
        {bitcask, ".*", {git, "git://github.com/basho/bitcask.git", "master"}}
       ]}.

all:
	test -d _build/default/lib/bitcask || rebar3 get-deps
	rebar3 compile
	@erl -noshell -pa './_build/default/lib/bitcask/ebin' -pa './_build/default/lib/bertie/ebin' -s bertie start

$ make
test -d _build/default/lib || rebar3 get-deps
===> Verifying dependencies...
===> Fetching bitcask (from {git,"git@github.com:basho/bitcask.git",
                   {ref,"d84c8d913713da8f02403431217405f84ee1ba22"}})
===> Fetching pc v1.15.0
===> Analyzing applications...
===> Compiling pc
===> Fetching eqc_rebar (from {git,"https://github.com/Quviq/eqc-rebar",{branch,"master"}})
===> Analyzing applications...
===> Compiling eqc_rebar
rebar3 compile
===> Verifying dependencies...
===> Compiling c_src/bitcask_nifs.c
===> Compiling c_src/erl_nif_util.c
===> Compiling c_src/murmurhash.c
===> Linking /home/hector/published/bertie/_build/default/lib/bitcask/priv/bitcask.so
===> Analyzing applications...
===> Compiling bitcask
===> Analyzing applications...
===> Compiling bertie
Bertie has been run 1 times

$ make
test -d _build/default/lib || rebar3 get-deps
rebar3 compile
===> Verifying dependencies...
===> Analyzing applications...
===> Compiling bertie
Bertie has been run 2 times

$ tree _build/default/plugins
_build/default/plugins
├── eqc_rebar
│   ├── ebin
│   │   ├── eqc_rebar.app
│   │   ├── eqc_rebar.beam
│   │   └── eqc_rebar_prv.beam
│   ├── LICENSE
│   ├── README.md
│   ├── rebar.config
│   └── src
│       ├── eqc_rebar.app.src
│       ├── eqc_rebar.erl
│       └── eqc_rebar_prv.erl
└── pc
    ├── ebin
    │   ├── pc.app
    │   ├── pc.beam
    │   ├── pc_compilation.beam
    │   ├── pc_port_env.beam
    │   ├── pc_port_specs.beam
    │   ├── pc_prv_clean.beam
    │   ├── pc_prv_compile.beam
    │   └── pc_util.beam
    ├── hex_metadata.config
    ├── LICENSE
    ├── README.md
    ├── rebar.config
    ├── rebar.lock
    └── src
        ├── pc.app.src
        ├── pc_compilation.erl
        ├── pc.erl
        ├── pc_port_env.erl
        ├── pc_port_specs.erl
        ├── pc_prv_clean.erl
        ├── pc_prv_compile.erl
        └── pc_util.erl

7 directories, 30 files

{deps, [
        {cowboy, ".*", {git, "git@github.com:ninenines/cowboy.git", "master"}},
        {ranch, ".*", {git, "git@github.com:ninenines/ranch.git", "master"}},
        {bitcask, ".*", {git, "git@github.com:basho/bitcask.git", {branch, "develop"}}}
       ]}.

$ rebar3 get-deps
===> Verifying dependencies...
===> Fetching eqc_rebar (from {git,"https://github.com/Quviq/eqc-rebar",{branch,"master"}})
===> Analyzing applications...
===> Compiling eqc_rebar
===> Fetching cowboy (from {git,"git@github.com:ninenines/cowboy.git","master"})
===> WARNING: It is recommended to use {branch, Name}, {tag, Tag} or {ref, Ref}, otherwise updating the dep may not work as expected.
===> Dependency failure: source for cowboy does not contain a recognizable project and can not be built

{deps, [
        {cowboy, "2.10.0"},
        {bitcask, ".*", {git, "git@github.com:basho/bitcask.git", {branch, "develop"}}}
       ]}.

$ rebar3 get-deps
===> Verifying dependencies...
===> Fetching bitcask (from {git,"git@github.com:basho/bitcask.git",
                   {ref,"d84c8d913713da8f02403431217405f84ee1ba22"}})
===> Fetching pc v1.15.0
===> Analyzing applications...
===> Compiling pc
===> Fetching eqc_rebar (from {git,"https://github.com/Quviq/eqc-rebar",{branch,"master"}})
===> Analyzing applications...
===> Compiling eqc_rebar
===> Fetching cowboy v2.10.0
===> Fetching cowlib v2.12.1
===> Fetching ranch v1.8.0

$ rebar3 compile
==> Verifying dependencies...
===> Compiling c_src/bitcask_nifs.c
===> Compiling c_src/erl_nif_util.c
===> Compiling c_src/murmurhash.c
===> Linking /home/hector/nobackup/erlang_imports/_build/default/lib/bitcask/priv/bitcask.so
===> Analyzing applications...
===> Compiling bitcask
===> Compiling ranch
===> Compiling cowlib
===> Compiling cowboy

%% Set paths to fix all dependencies
Home = os:getenv("HOME").
Dir = Home ++ "/nobackup/erlang_imports/_build/default/lib".
{ok, L} = file:list_dir(Dir).
lists:foreach(fun(I) ->
                Path = Dir ++ "/" ++ I ++ "/ebin",
                code:add_path(Path)
              end, L).

$ tree -L 3 ~/nobackup/erlang_imports/_build
/home/hector/nobackup/erlang_imports/_build
└── default
    ├── lib
    │   ├── bitcask
    │   ├── cowboy
    │   ├── cowlib
    │   └── ranch
    └── plugins
        ├── eqc_rebar
        └── pc

10 directories, 0 files

all:
	test -d _build/default/lib || rebar3 get-deps
	rebar3 compile
	@erl -noshell -pa './_build/default/lib/bertie/ebin' -s bertie start

start() ->                                                      %% Line 1
    start(8080).

start(Port) ->
    %% ok = application:start(crypto),                          %%      5
    %% {ok, _} = application:ensure_all_started(ranch),
    %% ok = application:start(cowlib),
    {ok, _} = application:ensure_all_started(cowboy),
    Dispatch = cowboy_router:compile(
                 [                                              %%     10
                  %% {URIHost, list(URIPath, Handler, Opts)}
                  {'_', [{'_', simple_web_server, []}]}
                 ]),
    cowboy:start_clear(my_simple_web_server,
                       [{port, Port}],                          %%     11
                       #{env => #{dispatch => Dispatch}}
                      ).

init(Req, State) ->                                                         %% Line 1
    Path = cowboy_req:path(Req),                                            %%      2
    Response = read_file(Path),                                             %%      3
    Req2 = cowboy_req:reply(200, #{                                         %%      4
                                   <<"content-type">> => <<"text/plain">>   %%      5
                                  }, Response, Req),                        %%      6
    {ok, Req2, State}.                                                      %%      7

read_file(Path) ->
    File = ["."|binary_to_list(Path)],
    case file:read_file(File) of
        {ok, Bin} -> Bin;
        _ -> ["<pre>cannot read:", File, "</pre>"]
    end.

terminate(_Reason, _Req, _State) ->
    ok.

$ erl -boot start_sasl -config elog4
...
1> ls().
elog4.config               index.html
simple_web_server.beam     simple_web_server.erl

ok
2> simple_web_server:start().
{ok,<0.127.0>}

$ curl --ipv4 http://localhost:8080/index.html -v
* Host localhost:8080 was resolved.
* IPv6: ::1
* IPv4: 127.0.0.1
*   Trying 127.0.0.1:8080...
* Established connection to localhost (127.0.0.1 port 8080) from 127.0.0.1 port 52938
* using HTTP/1.x
> GET /index.html HTTP/1.1
> Host: localhost:8080
> User-Agent: curl/8.16.0
> Accept: */*
>
* Request completely sent off
< HTTP/1.1 200 OK
< content-length: 22
< content-type: text/plain
< date: Wed, 05 Nov 2025 01:24:32 GMT
< server: Cowboy
<
<h1>Hello World!</h1>
* Connection #0 to host localhost:8080 left intact

init(Req, State) ->
    Path = cowboy_req:path(Req),
    handle(Path, Req, State).

handle(<<"/cgi">>, Req, State) ->
    Qstr = cowboy_req:parse_qs(Req),
    %% io:format("Qstr: ~p~n", [Qstr]),
    {ok, Bin, Req1} = cowboy_req:read_body(Req),
    {struct, Qbody} = mochijson2:decode(Bin),
    Response = call(Qstr, Qbody),
    Json = mochijson2:encode(Response),
    Req2 = cowboy_req:reply(200, #{
                                   <<"content-type">> => <<"text/json">>
                                  }, Json, Req1),
    Req3 = cowboy_req:set_resp_header(<<"access-control-allow-origin">>, <<"*">>, Req2),
    {ok, Req3, State};
handle(Path, Req, State) ->
    Response = read_file(Path),
    Req2 = cowboy_req:reply(200, #{
                                   <<"content-type">> => <<"text/html">>
                                  }, Response, Req),

call([{<<"mod">>,MB},{<<"func">>,FB}], X) ->
    Mod = list_to_atom(binary_to_list(MB)),
    Func = list_to_atom(binary_to_list(FB)),

-module(echo).
-export([me/1]).

me(X) ->
    io:format("echo: ~p~n", [X]),
    X.

$ erl -boot start_sasl -config elog4
...
1> cgi_web_server:start().
{ok,<0.126.0>}
echo: [{<<"Name">>,<<"Hector PENG">>},{<<"Height">>,181}]

$ curl --ipv4 -v "http://localhost:8080/cgi?mod=echo&func=me" -H "Content-Type:application/json" -X POST --data '{"Name": "Hector PENG", "Height": 181}'
Note: Unnecessary use of -X or --request, POST is already inferred.
* Host localhost:8080 was resolved.
* IPv6: ::1
* IPv4: 127.0.0.1
*   Trying 127.0.0.1:8080...
* Established connection to localhost (127.0.0.1 port 8080) from 127.0.0.1 port 42290
* using HTTP/1.x
> POST /cgi?mod=echo&func=me HTTP/1.1
> Host: localhost:8080
> User-Agent: curl/8.16.0
> Accept: */*
> Content-Type:application/json
> Content-Length: 38
>
* upload completely sent off: 38 bytes
< HTTP/1.1 200 OK
< content-length: 35
< content-type: text/json
< date: Wed, 05 Nov 2025 06:45:32 GMT
< server: Cowboy
<
* Connection #0 to host localhost:8080 left intact
{"Name":"Hector PENG","Height":181}%

<script src="jquery-3.7.1.min.js"></script>
<h1>Test2</h1>
<button id="button1">click</button>

<div id="result"></div>
<script>
  $(document).ready(go);

  var data = {int:1234,
    string:"abcd",
    array:[1,2,3,'abc'],
    map:{one:'abc', two:1, three:"abc"}};

  function go(){
    $("#button1").click(test);
  }

  function test(){
    $.ajax({url:"http://localhost:8080/cgi?mod=echo&func=me",
      type: 'POST',
      data: JSON.stringify(data),
      success: function(ret){
        $("#result").html("<pre>"+ JSON.stringify(ret, undefined, 4) + "</pre>");
        }});
        }
</script>

$ erl -boot start_sasl -config elog4
Erlang/OTP 28 [erts-16.0.3] [source] [64-bit] [smp:12:12] [ds:12:12:10] [async-threads:1] [jit:ns]

Eshell V16.0.3 (press Ctrl+G to abort, type help(). for help)
1> cgi_web_server:start().
{ok,<0.126.0>}

echo: [{<<"int">>,1234},
       {<<"string">>,<<"abcd">>},
       {<<"array">>,[1,2,3,<<"abc">>]},
       {<<"map">>,
        {struct,[{<<"one">>,<<"abc">>},
                 {<<"two">>,1},
                 {<<"three">>,<<"abc">>}]}}]

start_from_shell([PortAsAtom]) ->
    PortAsInt = list_to_integer(atom_to_list(PortAsAtom)),
    start(PortAsInt).

$ erl -boot start_sasl -config elog4 -s cgi_web_server start_from_shell 8080

$ tree -L 2
.
├── bbmustache
│   └── ebin
├── certifi
│   └── ebin
├── cf
│   └── ebin
├── cth_readable
│   └── ebin
├── erlware_commons
│   └── ebin
├── eunit_formatters
│   └── ebin
├── getopt
│   └── ebin
├── providers
│   └── ebin
├── rebar
│   ├── ebin
│   └── priv
├── relx
│   ├── ebin
│   └── priv
└── ssl_verify_fun
    └── ebin

25 directories, 0 files

Erlang 编程

第三方程序

使用 Rebar 构造可共享归档以及管理咱们的代码

安装 `rebar`

在 GitHub 上构造一个新的项目

将该项目克隆到本地

构造一个 OTP 应用

公布咱们的项目

将外部程序与我们的代码集成

构造依赖项的本地拷贝

以 Cowboy 构建嵌入式 Web 服务器

练习