Add dubbo-erlang user doc (#382)

docs/en-us/user/languages/erlang/reference.md

@@ -0,0 +1,15 @@
+# Consumer Configurations
+
+## Base Config
+Consumer config is under the dubboerl application with sys.config
+```erlang
+{dubboerl,[
+	%% other config ...
+	{consumer,[
+		{<<"interface fullname">>,[Option]},
+		%% eg:
+		{<<"org.apache.dubbo.erlang.sample.service.facade.UserOperator">>,[]},
+	]}
+]}
+```
+Option is to be added.

docs/en-us/user/languages/erlang/serialization.md

@@ -0,0 +1,17 @@
+# Protocol Configurations
+
+The library now only supports hessian and json serialization.
+
+## Configuration example
+Protocol config is under the dubboerl application with sys.config
+```erlang
+{dubboerl,[
+	%% other config ...
+	{protocol,hessian}
+]}
+```
+
+| ConfigName | Type | DefaultValue | Remarks |
+| --- | --- | --- | --- |
+| protocol | atom() | hessian | hessian,json |
+

docs/en-us/user/languages/erlang/service.md

@@ -0,0 +1,22 @@
+# Provider Configurations
+
+## Base Config
+Provider config is under the dubboerl application with sys.config
+```erlang
+{dubboerl,[
+	%% other config ...
+	{provider,[
+		{module_implements,interface_module,interface_fullname,[Options]},
+		%% eg:
+		{userOperator_impl,userOperator,<<"org.apache.dubbo.erlang.sample.service.facade.UserOperator">>,[Option]}
+	]}
+]}
+```
+
+| ConfigName | Type | DefaultValue | Remarks |
+| --- | --- | --- | --- |
+| module_implements | atom() | - | The service implements module name|
+| interface_module | atom() | - | Interface module name is transfer form java jar |
+| interface_fullname | binary() | - | Interface full name is the java class name |
+
+Option is to be added.

docs/en-us/user/languages/erlang/start.md

@@ -0,0 +1,62 @@
+# Quick Start
+
+We recommend using java to define the Dubbo interface. And use [erlanalysis](https://github.com/apache/dubbo-erlang/tree/master/tools/erlanalysis) 
+tool parse java interface transfer to erlang lib.
+
+## Import Dependency Lib
+
+
+### Using Rebar Build Tool
+Add dubblerl to rebar.config with your project
+```erlang
+{deps, [
+    {dubboerl, {git, "https://github.com/apache/dubbo-erlang.git", {branch, "master"}}}
+]}.
+```
+
+### User erlang.mk Build Tool
+`Waiting for improvement`
+
+## Import interface lib
+Suppose the interface lib you exported is called dubbo_service.   
+* If you didn't upload your lib to your git repository, It is recommended that you copy the `dubbo_service` lib 
+into the project's `apps` directory.  
+* If it is upload to your git repository, you can import like this:
+```erlang
+{deps, [
+    {dubboerl, {git, "https://github.com/apache/dubbo-erlang.git", {branch, "master"}}},
+    {dubbo_service,{git,"${INTERFACE_LIB_URL}",{branch,"master"}}} %% replace ${INTERFACE_LIB_URL} with your lib git repos url
+]}.
+```
+
+## Consumer Configuration
+Please reference [Reference Config](./reference.md)
+
+## Init dubbolib in your project
+It is need you 
+```erlang
+dubboerl:init().
+```
+
+## How to invoke?
+
+### Sync Call
+```erlang
+Request = #userInfoRequest{requestId = 123, username = "testname"},
+{ok,RequestRef,Response,RpcContent}  = userOperator:queryUserInfo(Request,#{sync=> true}).
+```
+If it occur error, is reponse `{error,Reason}`. 
+
+### Async Call
+
+Default is Async call.
+```erlang
+Request = #userInfoRequest{requestId = 123, username = "testname"},
+{ok,RequestRef} = userOperator:queryUserInfo(Request).
+
+%% you can receive the message after.
+{msg_back,RequestRef,Response,RpcContent}.
+```
+
+## Sample
+Reference the demo project [dubboerl_demo](https://github.com/apache/dubbo-erlang/tree/master/samples)

docs/zh-cn/user/languages/erlang/reference.md

@@ -0,0 +1,15 @@
+# 消费者配置
+
+## 基础配置
+消费者配置项需要添加到`sys.config`文件`dubboerl`应用配置项里。
+```erlang
+{dubboerl,[
+	%% other config ...
+	{consumer,[
+		{<<"interface fullname">>,[Option]},
+		%% eg:
+		{<<"org.apache.dubbo.erlang.sample.service.facade.UserOperator">>,[]},
+	]}
+]}
+```
+Option 配置项待添加中.

docs/zh-cn/user/languages/erlang/serialization.md

@@ -0,0 +1,21 @@
+# 序列化配置项
+
+当前该库只实现了`dubbo://`通讯协议。
+
+序列化方式实现了`hessian`和`json`两种方式。
+
+## 配置样例
+
+序列化配置需要添加到`sys.config`文件`dubboerl`应用配置项里。
+
+```erlang
+{dubboerl,[
+	%% other config ...
+	{protocol,hessian}
+]}
+```
+
+| ConfigName | Type | DefaultValue | Remarks |
+| --- | --- | --- | --- |
+| protocol | atom() | hessian | hessian,json |
+

docs/zh-cn/user/languages/erlang/service.md

@@ -0,0 +1,22 @@
+# 提供者配置
+
+## 基本配置
+提供者配置项需要添加到`sys.config`文件`dubboerl`应用配置项里。
+```erlang
+{dubboerl,[
+	%% other config ...
+	{provider,[
+		{module_implements,interface_module,interface_fullname,[Options]},
+		%% eg:
+		{userOperator_impl,userOperator,<<"org.apache.dubbo.erlang.sample.service.facade.UserOperator">>,[Option]}
+	]}
+]}
+```
+
+| ConfigName | Type | DefaultValue | Remarks |
+| --- | --- | --- | --- |
+| module_implements | atom() | - | The service implements module name|
+| interface_module | atom() | - | Interface module name is transfer form java jar |
+| interface_fullname | binary() | - | Interface full name is the java class name |
+
+Option is to be added.

docs/zh-cn/user/languages/erlang/start.md

@@ -0,0 +1,60 @@
+# 快速开始
+
+建议先使用java定义接口jar，并使用[erlanalysis](https://github.com/apache/dubbo-erlang/tree/master/tools/erlanalysis) 工具解析java接口至Erlang lib
+
+## 导入依赖库
+
+### 使用 Rebar 编译工具。
+Add dubblerl to rebar.config with your project
+```erlang
+{deps, [
+    {dubboerl, {git, "https://github.com/apache/dubbo-erlang.git", {branch, "master"}}}
+]}.
+```
+
+### 使用 erlang.mk 编译工具
+`待补充`
+
+## 导入接口库
+Suppose the interface lib you exported is called dubbo_service.   
+* If you didn't upload your lib to your git repository, It is recommended that you copy the `dubbo_service` lib 
+into the project's `apps` directory.  
+* If it is upload to your git repository, you can import like this:
+```erlang
+{deps, [
+    {dubboerl, {git, "https://github.com/apache/dubbo-erlang.git", {branch, "master"}}},
+    {dubbo_service,{git,"${INTERFACE_LIB_URL}",{branch,"master"}}} %% replace ${INTERFACE_LIB_URL} with your lib git repos url
+]}.
+```
+
+## 消费者配置
+Please reference [Reference Config](./reference.md)
+
+## Init dubbolib in your project
+It is need you 
+```erlang
+dubboerl:init().
+```
+
+## 如何调用？
+
+### 同步调用
+```erlang
+Request = #userInfoRequest{requestId = 123, username = "testname"},
+{ok,RequestRef,Response,RpcContent}  = userOperator:queryUserInfo(Request,#{sync=> true}).
+```
+If it occur error, is reponse `{error,Reason}`. 
+
+### 异步调用
+
+Default is Async call.
+```erlang
+Request = #userInfoRequest{requestId = 123, username = "testname"},
+{ok,RequestRef} = userOperator:queryUserInfo(Request).
+
+%% you can receive the message after.
+handle_cast({msg_back,RequestRef,Response,RpcContent},State).
+```
+
+## 示例
+参考项目 [dubboerl_demo](https://github.com/apache/dubbo-erlang/tree/master/samples)

site_config/docs.js

@@ -405,6 +405,27 @@ export default {
                     {
                         title: 'Test coverage report',
                         link: '/en-us/docs/user/coveragence.html'
+                    },
+                    {
+                        title: 'Erlang languages',
+                        children: [
+                            {
+                                title: 'Quick start',
+                                link: '/en-us/docs/user/languages/erlang/start.html'
+                            },
+                            {
+                                title: 'Reference configuration',
+                                link: '/en-us/docs/user/languages/erlang/reference.html'
+                            },
+                            {
+                                title: 'Service configuration',
+                                link: '/en-us/docs/user/languages/erlang/service.html'
+                            },
+                            {
+                                title: 'Serialization configuration',
+                                link: '/en-us/docs/user/languages/erlang/serialization.html'
+                            }
+                        ]
                     }
                 ],
             },
@@ -1044,6 +1065,27 @@ export default {
                                 link: '/zh-cn/docs/user/versions/version-270.html'
                             }
                         ]
+                    },
+                    {
+                        title: 'Erlang 语言',
+                        children: [
+                            {
+                                title: '快速启动',
+                                link: '/zh-cn/docs/user/languages/erlang/start.html'
+                            },
+                            {
+                                title: '消费者配置',
+                                link: '/zh-cn/docs/user/languages/erlang/reference.html'
+                            },
+                            {
+                                title: '提供者配置',
+                                link: '/zh-cn/docs/user/languages/erlang/service.html'
+                            },
+                            {
+                                title: '序列化配置',
+                                link: '/zh-cn/docs/user/languages/erlang/serialization.html'
+                            }
+                        ]
                     }
                 ],
             },