feat: add degraphql plugin

apisix/plugins/degraphql.lua

@@ -0,0 +1,160 @@
+--
+-- Licensed to the Apache Software Foundation (ASF) under one or more
+-- contributor license agreements.  See the NOTICE file distributed with
+-- this work for additional information regarding copyright ownership.
+-- The ASF licenses this file to You under the Apache License, Version 2.0
+-- (the "License"); you may not use this file except in compliance with
+-- the License.  You may obtain a copy of the License at
+--
+--     http://www.apache.org/licenses/LICENSE-2.0
+--
+-- Unless required by applicable law or agreed to in writing, software
+-- distributed under the License is distributed on an "AS IS" BASIS,
+-- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+-- See the License for the specific language governing permissions and
+-- limitations under the License.
+--
+local core = require("apisix.core")
+local gq_parse = require("graphql").parse
+local req_set_body_data = ngx.req.set_body_data
+local ipairs = ipairs
+local pcall = pcall
+local type = type
+
+
+local schema = {
+    type = "object",
+    properties = {
+        query = {
+            type = "string",
+            minLength = 1,
+            maxLength = 1024,
+        },
+        variables = {
+            type = "array",
+            items = {
+                type = "string"
+            },
+            minItems = 1,
+        },
+        operation_name = {
+            type = "string",
+            minLength = 1,
+            maxLength = 1024
+        },
+    },
+    required = {"query"},
+}
+
+local plugin_name = "degraphql"
+
+local _M = {
+    version = 0.1,
+    priority = 509,
+    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
+
+    local ok, res = pcall(gq_parse, conf.query)
+    if not ok then
+        return false, "failed to parse query: " .. res
+    end
+
+    if #res.definitions > 1 and not conf.operation_name then
+        return false, "operation_name is required if multiple operations are present in the query"
+    end
+    return true
+end
+
+
+local function fetch_post_variables(conf)
+    local req_body, err = core.request.get_body()
+    if err ~= nil then
+        core.log.error("failed to get request body: ", err)
+        return nil, 503
+    end
+
+    if not req_body then
+        core.log.error("missing request body")
+        return nil, 400
+    end
+
+    -- JSON as the default content type
+    req_body, err = core.json.decode(req_body)
+    if type(req_body) ~= "table" then
+        core.log.error("invalid request body can't be decoded: ", err or "bad type")
+        return nil, 400
+    end
+
+    local variables = {}
+    for _, v in ipairs(conf.variables) do
+        variables[v] = req_body[v]
+    end
+
+    return variables
+end
+
+
+local function fetch_get_variables(conf)
+    local args = core.request.get_uri_args()
+    local variables = {}
+    for _, v in ipairs(conf.variables) do
+        variables[v] = args[v]
+    end
+
+    return variables
+end
+
+
+function _M.access(conf, ctx)
+    local meth = core.request.get_method()
+    if meth ~= "POST" and meth ~= "GET" then
+        return 405
+    end
+
+    local new_body = core.table.new(0, 3)
+
+    if conf.variables then
+        local variables, code
+        if meth == "POST" then
+            variables, code = fetch_post_variables(conf)
+        else
+            variables, code = fetch_get_variables(conf)
+        end
+
+        if not variables then
+            return code
+        end
+
+        if meth == "POST" then
+            new_body["variables"] = variables
+        else
+            new_body["variables"] = core.json.encode(variables)
+        end
+    end
+
+    new_body["operationName"] = conf.operation_name
+    new_body["query"] = conf.query
+
+    if meth == "POST" then
+        if not conf.variables then
+            -- the set_body_data requires to read the body first
+            core.request.get_body()
+        end
+
+        core.request.set_header(ctx, "Content-Type", "application/json")
+        req_set_body_data(core.json.encode(new_body))
+    else
+        core.request.set_uri_args(ctx, new_body)
+    end
+end
+
+
+return _M

ci/pod/docker-compose.plugin.yml

@@ -313,6 +313,12 @@ services:
     ports:
       - '7002:6379'
 
+  graphql-demo:
+    # the owner doesn't provide a semver tag
+    image: npalm/graphql-java-demo:latest
+    ports:
+      - '8888:8080'
+
 networks:
   apisix_net:
   kafka_net:

ci/pod/openfunction/function-example/test-uri/go.mod

@@ -20,7 +20,7 @@ require (
 	go.uber.org/atomic v1.9.0 // indirect
 	go.uber.org/multierr v1.7.0 // indirect
 	go.uber.org/zap v1.21.0 // indirect
-	golang.org/x/net v0.0.0-20220621193019-9d032be2e588 // indirect
+	golang.org/x/net v0.0.0-20220722155237-a158d28d115b // indirect
 	golang.org/x/sys v0.0.0-20220722155257-8c9f86f7a55f // indirect
 	golang.org/x/text v0.3.8 // indirect
 	google.golang.org/genproto v0.0.0-20220622171453-ea41d75dfa0f // indirect

ci/pod/openfunction/function-example/test-uri/go.sum

@@ -1941,7 +1941,6 @@ golang.org/x/net v0.0.0-20220127200216-cd36cc0744dd/go.mod h1:CfG3xpIq0wQ8r1q4Su
 golang.org/x/net v0.0.0-20220225172249-27dd8689420f/go.mod h1:CfG3xpIq0wQ8r1q4Su4UZFWDARRcnwPjda9FqA0JpMk=
 golang.org/x/net v0.0.0-20220325170049-de3da57026de/go.mod h1:CfG3xpIq0wQ8r1q4Su4UZFWDARRcnwPjda9FqA0JpMk=
 golang.org/x/net v0.0.0-20220425223048-2871e0cb64e4/go.mod h1:CfG3xpIq0wQ8r1q4Su4UZFWDARRcnwPjda9FqA0JpMk=
-golang.org/x/net v0.0.0-20220621193019-9d032be2e588 h1:9ubFuySsnAJYGyJrZ3koiEv8FyqofCBdz3G9Mbf2YFc=
 golang.org/x/net v0.0.0-20220621193019-9d032be2e588/go.mod h1:XRhObCWvk6IyKnWLug+ECip1KBveYUHfp+8e9klMJ9c=
 golang.org/x/net v0.0.0-20220722155237-a158d28d115b h1:PxfKdU9lEEDYjdIzOtC4qFWgkU2rGHdKlKowJSMN9h0=
 golang.org/x/net v0.0.0-20220722155237-a158d28d115b/go.mod h1:XRhObCWvk6IyKnWLug+ECip1KBveYUHfp+8e9klMJ9c=

conf/config-default.yaml

@@ -459,6 +459,7 @@ plugins:                          # plugin list (sorted by priority)
   - traffic-split                  # priority: 966
   - redirect                       # priority: 900
   - response-rewrite               # priority: 899
+  - degraphql                      # priority: 509
   - kafka-proxy                    # priority: 508
   #- dubbo-proxy                   # priority: 507
   - grpc-transcode                 # priority: 506

docs/en/latest/config.json

@@ -76,6 +76,7 @@
             "plugins/grpc-web",
             "plugins/fault-injection",
             "plugins/mocking",
+            "plugins/degraphql",
             "plugins/body-transformer"
           ]
         },