docs: lua filter (#279)

Signed-off-by: Matt Klein <mklein@lyft.com>

api/BUILD

@@ -147,6 +147,7 @@ proto_library(
         ":protocol",
         ":rds",
         "//api/filter/accesslog:accesslog",
+        "//api/filter/http:lua",
         "//api/filter/network:http_connection_manager",
         "//api/filter/network:mongo_proxy",
     ],

api/filter/http/lua.proto

@@ -2,9 +2,15 @@ syntax = "proto3";
 
 package envoy.api.v2.filter.http;
 
-// The Lua filter allows for generic scripting in an HTTP filter context.
-// TODO(mattklein123): Link to filter docs.
+import "validate/validate.proto";
+
+// [#protodoc-title: Lua]
+// Lua :ref:`configuration overview <config_http_filters_lua>`.
+
 message Lua {
-  // The Lua code to execute.
-  string inline_code = 1;
+  // The Lua code that Envoy will execute. This can be a very small script that
+  // further loads code from disk if desired. Note that if JSON configuration is used, the code must
+  // be properly escaped. YAML configuration may be easier to read since YAML supports multi-line
+  // strings so complex scripts can be easily expressed inline in the configuration.
+  string inline_code = 1 [(validate.rules).string.min_len = 1];
 }

docs/build.sh

@@ -38,6 +38,7 @@ PROTO_RST="
   /api/sds/api/sds.proto.rst
   /api/filter/accesslog/accesslog/api/filter/accesslog/accesslog.proto.rst
   /api/filter/fault/api/filter/fault.proto.rst
+  /api/filter/http/lua/api/filter/http/lua.proto.rst
   /api/filter/network/http_connection_manager/api/filter/network/http_connection_manager.proto.rst
   /api/filter/network/mongo_proxy/api/filter/network/mongo_proxy.proto.rst
   /api/protocol/api/protocol.proto.rst

docs/root/api-v1/http_filters/lua_filter.rst

@@ -0,0 +1,21 @@
+.. _config_http_filters_lua_v1:
+
+Lua
+===
+
+Lua :ref:`configuration overview <config_http_filters_lua>`.
+
+.. code-block:: json
+
+  {
+    "name": "lua",
+    "config": {
+      "inline_code": "..."
+    }
+  }
+
+inline_code
+  *(required, string)* The Lua code that Envoy will execute. This can be a very small script that
+  further loads code from disk if desired. Note that if JSON configuration is used, the code must
+  be properly escaped. YAML configuration may be easier to read since YAML supports multi-line
+  strings so complex scripts can be easily expressed inline in the configuration.

docs/root/api-v2/filter/http/http.rst

@@ -8,4 +8,5 @@ HTTP filters
 .. toctree::
   :glob:
   :maxdepth: 2
-
+  
+  *

docs/root/configuration/http_filters/lua_filter.rst

@@ -55,20 +55,8 @@ API.
 Configuration
 -------------
 
-.. code-block:: json
-
-  {
-    "name": "lua",
-    "config": {
-      "inline_code": "..."
-    }
-  }
-
-inline_code
-  *(required, string)* The Lua code that Envoy will execute. This can be a very small script that
-  further loads code from disk if desired. Note that if JSON configuration is used, the code must
-  be properly escaped. YAML configuration may be easier to read since YAML supports multi-line
-  strings so complex scripts can be easily expressed inline in the configuration.
+* :ref:`v1 configuration <config_http_filters_lua_v1>`
+* :ref:`v2 configuration <envoy_api_msg_filter.http.Lua>`
 
 Script examples
 ---------------