feature(plugin): rewrite upstream info with plugin proxy-rewrite (#594

)

* test: add `proxy-rewrite` plugin test cases

conf/config.yaml

@@ -54,6 +54,7 @@ plugins:                          # plugin list
   - serverless-pre-function
   - serverless-post-function
   - openid-connect
+  - proxy-rewrite
 
 stream_plugins:
   - mqtt-proxy

doc/plugins/proxy-rewrite-cn.md

@@ -0,0 +1,72 @@
+[English](proxy-rewrite.md)
+# proxy-rewrite
+
+上游代理信息重写插件。
+
+#### 配置参数
+|名字    |可选|说明|
+|-------         |-----|------|
+|scheme          |可选| 转发到上游的新`schema` 协议，可以是`http`或`https`，默认`http`协议|
+|uri             |可选| 转发到上游的新`uri` 地址|
+|host            |可选| 转发到上游的新`host` 地址，例如：`iresty.com` |
+|enable_websocket|可选| 是否启用`websocket`（布尔值），默认不启用|
+
+### 示例
+
+#### 开启插件
+下面是一个示例，在指定的 route 上开启了 `proxy rewrite` 插件:
+
+```shell
+curl http://127.0.0.1:9080/apisix/admin/routes/1 -X PUT -d '
+{
+    "methods": ["GET"],
+    "uri": "/test/index.html",
+    "plugins": {
+        "proxy-rewrite": {
+            "uri": "/test/home.html",
+            "scheme": "http",
+            "host": "iresty.com",
+            "enable_websocket": true
+        }
+    },
+    "upstream": {
+        "type": "roundrobin",
+        "nodes": {
+            "127.0.0.1:80": 1
+        }
+    }
+}'
+```
+
+#### 测试插件
+基于上述配置进行测试：
+```shell
+curl -X GET http://127.0.0.1:9080/test/index.html
+```
+
+发送请求，查看上游服务`access.log`，如果输出信息与配置一致：
+```
+127.0.0.1 - [26/Sep/2019:10:52:20 +0800] iresty.com GET /test/home.html HTTP/1.1 200 38 - curl/7.29.0 - 0.000 199 107
+```
+
+即表示 `proxy rewrite` 插件生效了。
+
+#### 禁用插件
+当你想去掉 `proxy rewrite` 插件的时候，很简单，在插件的配置中把对应的 json 配置删除即可，无须重启服务，即刻生效：
+
+```shell
+curl http://127.0.0.1:9080/apisix/admin/routes/1 -X PUT -d '
+{
+    "methods": ["GET"],
+    "uri": "/test/index.html",
+    "plugins": {},
+    "upstream": {
+        "type": "roundrobin",
+        "nodes": {
+            "127.0.0.1:80": 1
+        }
+    }
+}'
+```
+
+现在就已经移除了 `proxy rewrite` 插件了。其他插件的开启和移除也是同样的方法。

doc/plugins/proxy-rewrite.md

@@ -0,0 +1,73 @@
+[中文](proxy-rewrite-cn.md)
+# proxy-rewrite
+
+upstream proxy info rewrite plugin.
+
+### Parameters
+|Name    |Required|Description|
+|-------         |-----|------|
+|scheme          |No| Upstream new `schema` forwarding protocol,options can be `http` or `https`,default `http`.|
+|uri             |No| Upstream new `uri` forwarding address.|
+|host            |No| Upstream new `host` forwarding address, example `iresty.com`. |
+|enable_websocket|No| enable `websocket`(boolean), default `false`.|
+
+### Example
+
+#### Enable Plugin
+Here's an example, enable the `proxy rewrite` plugin on the specified route:
+
+```shell
+curl http://127.0.0.1:9080/apisix/admin/routes/1 -X PUT -d '
+{
+    "methods": ["GET"],
+    "uri": "/test/index.html",
+    "plugins": {
+        "proxy-rewrite": {
+            "uri": "/test/home.html",
+            "scheme": "http",
+            "host": "iresty.com",
+            "enable_websocket": true
+        }
+    },
+    "upstream": {
+        "type": "roundrobin",
+        "nodes": {
+            "127.0.0.1:80": 1
+        }
+    }
+}'
+```
+
+#### Test Plugin
+Testing based on the above examples :
+```shell
+curl -X GET http://127.0.0.1:9080/test/index.html
+```
+
+Send the request and see upstream `access.log', if the output information is consistent with the configuration :
+```
+127.0.0.1 - [26/Sep/2019:10:52:20 +0800] iresty.com GET /test/home.html HTTP/1.1 200 38 - curl/7.29.0 - 0.000 199 107
+```
+
+This means that the `proxy rewrite` plugin is in effect.
+
+#### Disable Plugin
+When you want to disable the `proxy rewrite` plugin, it is very simple,
+ you can delete the corresponding json configuration in the plugin configuration,
+  no need to restart the service, it will take effect immediately :
+```shell
+curl http://127.0.0.1:9080/apisix/admin/routes/1 -X PUT -d '
+{
+    "methods": ["GET"],
+    "uri": "/test/index.html",
+    "plugins": {},
+    "upstream": {
+        "type": "roundrobin",
+        "nodes": {
+            "127.0.0.1:80": 1
+        }
+    }
+}'
+```
+
+The `proxy rewrite` plugin has been disabled now. It works for other plugins.

lua/apisix/plugins/proxy-rewrite.lua

@@ -0,0 +1,77 @@
+local core        = require("apisix.core")
+local plugin_name = "proxy-rewrite"
+local pairs       = pairs
+local ipairs      = ipairs
+
+local schema = {
+    type = "object",
+    properties = {
+        uri = {
+            description = "new uri for upstream",
+            type        = "string",
+            minLength   = 1,
+            maxLength   = 4096
+        },
+        host = {
+            description = "new host for upstream",
+            type        = "string",
+            pattern     = "^\\*?[0-9a-zA-Z-.]+$",
+        },
+        scheme = {
+            description = "new scheme for upstream",
+            type    = "string",
+            enum    = {"http", "https"}
+        },
+        enable_websocket = {
+            description = "enable websocket for request",
+            type        = "boolean",
+            default     = false
+        }
+    },
+    minProperties = 1,
+}
+
+local _M = {
+    version  = 0.1,
+    priority = 1008,
+    name     = plugin_name,
+    schema   = schema,
+}
+
+function _M.check_schema(conf)
+    local ok, err = core.schema.check(schema, conf)
+    if not ok then
+        return false, err
+    end
+    return true
+end
+
+do
+    local upstream_vars = {
+        uri        = "upstream_uri",
+        scheme     = "upstream_scheme",
+        host       = "upstream_host",
+        upgrade    = "upstream_upgrade",
+        connection = "upstream_connection",
+    }
+    local upstream_names = {}
+    for name, _ in pairs(upstream_vars) do
+        core.table.insert(upstream_names, name)
+    end
+
+function _M.rewrite(conf, ctx)
+    for _, name in ipairs(upstream_names) do
+        if conf[name] then
+            ctx.var[upstream_vars[name]] = conf[name]
+        end
+    end
+
+    if conf.enable_websocket then
+        ctx.var["upstream_upgrade"]    = ctx.var["http_upgrade"]
+        ctx.var["upstream_connection"] = ctx.var["http_connection"]
+    end
+end
+
+end  -- do
+
+return _M

t/APISIX.pm

@@ -154,6 +154,7 @@ _EOC_
         listen 1980;
         listen 1981;
         listen 1982;
+        server_name apisix.iresty.com;
 
         server_tokens off;
 

t/admin/plugins.t

@@ -14,6 +14,6 @@ __DATA__
 --- request
 GET /apisix/admin/plugins/list
 --- response_body_like eval
-qr/\["limit-req","limit-count","limit-conn","key-auth","prometheus","node-status","jwt-auth","zipkin","ip-restriction","grpc-transcode","serverless-pre-function","serverless-post-function","openid-connect"\]/
+qr/\["limit-req","limit-count","limit-conn","key-auth","prometheus","node-status","jwt-auth","zipkin","ip-restriction","grpc-transcode","serverless-pre-function","serverless-post-function","openid-connect","proxy-rewrite"\]/
 --- no_error_log
 [error]

t/debug-mode.t

@@ -44,6 +44,7 @@ loaded plugin and sort by priority: 3000 name: ip-restriction
 loaded plugin and sort by priority: 2599 name: openid-connect
 loaded plugin and sort by priority: 2510 name: jwt-auth
 loaded plugin and sort by priority: 2500 name: key-auth
+loaded plugin and sort by priority: 1008 name: proxy-rewrite
 loaded plugin and sort by priority: 1003 name: limit-conn
 loaded plugin and sort by priority: 1002 name: limit-count
 loaded plugin and sort by priority: 1001 name: limit-req

t/lib/server.lua

@@ -1,4 +1,5 @@
 local json_decode = require("cjson").decode
+local json_encode = require("cjson").encode
 
 local _M = {}
 
@@ -22,6 +23,11 @@ function _M.limit_conn()
     ngx.say("hello world")
 end
 
+function _M.plugin_proxy_rewrite()
+    ngx.say("uri: ", ngx.var.uri)
+    ngx.say("host: ", ngx.var.host)
+    ngx.say("scheme: ", ngx.var.scheme)
+end
 
 function _M.status()
     ngx.say("ok")