fix(degraphql): handle multiple parameter types when converting query…

… parameters (#9911)

After the query parameters of the graphql are parsed into AST, there are three types: listType, nonNullType, and namedType.
Are their structures different, so the way of obtaining variable types from the structure is also different.

This PR is compatible with different structures for obtaining variable types.

Fix FTI-6153

changelog/unreleased/kong-ee/plugins-degraphql-handle-variable-type.yml

@@ -0,0 +1,3 @@
+message: "**degraphql**: Fixed an issue where multiple parameter types were not handled correctly when converting query parameters."
+type: bugfix
+scope: Plugin

kong/plugins/degraphql/handler.lua

@@ -17,7 +17,6 @@ local workspaces = require "kong.workspaces"
 
 local type = type
 local ipairs = ipairs
-local fmt = string.format
 
 local FORCE = true
 
@@ -109,8 +108,22 @@ local function coerce_query_variable(query_str, args)
 
   if variable_definition and type(variable_definition) == "table" then
     for _, variable in ipairs(variable_definition) do
+      local var_kind = variable.type.kind
+      local var_type
+      if var_kind == "listType" or  var_kind == "nonNullType" then
+        var_type = variable.type.type.name.value
+      end
+
+      if var_kind == "namedType" then
+        var_type = variable.type.name.value
+      end
+
+      if not var_type then
+        kong.log.err("unsupported variable type: ", var_kind)
+        return
+      end
+
       local var_name = variable.variable.name.value
-      local var_type = variable.type.type.name.value
       local var_value = args[var_name]
 
       if var_value then

spec-ee/03-plugins/20-degraphql/02-access_spec.lua

@@ -56,6 +56,27 @@ local graphql_mock_query = {
       }
     }
   ]],
+
+  query_with_mixed_param_type = [[
+    query($repoCount: [Int], $rating: Float!, $isActive: Boolean) {
+      user {
+        id
+        name
+        isActive @include(if: $isActive)
+        repositories(last: $repoCount) {
+          nodes {
+            id
+            name
+            languages: stars(rating: $rating)
+          }
+        }
+        friends: following {
+          name
+          isActive
+        }
+      }
+    }
+  ]],
 }
 
 for _, strategy in helpers.each_strategy() do
@@ -122,6 +143,12 @@ for _, strategy in helpers.each_strategy() do
         query = graphql_mock_query.fetch_recent_repos,
       })
 
+      assert(db.degraphql_routes:insert {
+        service = { id = service.id },
+        uri = "/query_with_mixed_param_type",
+        query = graphql_mock_query.query_with_mixed_param_type,
+      })
+
       helpers.start_kong({
         database = strategy,
         plugins = "bundled,degraphql",
@@ -197,6 +224,25 @@ for _, strategy in helpers.each_strategy() do
       assert.response(res).has.status(200)
       local json = assert.response(res).has.jsonbody()
       assert.same(ori_graph_query, json.data.variables)
+
+      local ori_graph_query_with_mixed_param_type = {
+        repoCount = 3, -- A signed 32‐bit integer
+        rating = 4.5, -- A signed double-precision floating-point value.
+        isActive = true, -- true or false.
+      }
+
+      local res = assert(proxy_client:send {
+        method  = "GET",
+        path    = "/query_with_mixed_param_type",
+        query   = ori_graph_query_with_mixed_param_type,
+        headers = {
+          ["Host"] = "graphql.test"
+        }
+      })
+
+      assert.response(res).has.status(200)
+      local json = assert.response(res).has.jsonbody()
+      assert.same(ori_graph_query_with_mixed_param_type, json.data.variables)
     end)
 
     it("can update graphql router when creating new graphql_route entity", function ()