Add limit reaching error codes

Fixes #134.

Author: Totktonada

graphql/accessor_general.lua

@@ -13,8 +13,10 @@ local bit = require('bit')
 local rex, is_pcre2 = utils.optional_require_rex()
 local avro_helpers = require('graphql.avro_helpers')
 local db_schema_helpers = require('graphql.db_schema_helpers')
+local error_codes = require('graphql.error_codes')
 
 local check = utils.check
+local e = error_codes
 
 -- XXX: consider using [1] when it will be mature enough;
 -- look into [2] for the status.
@@ -856,12 +858,17 @@ local function process_tuple(self, state, tuple, opts)
     local resulting_object_cnt_max = opts.resulting_object_cnt_max
     local fetched_object_cnt_max = opts.fetched_object_cnt_max
     qstats.fetched_object_cnt = qstats.fetched_object_cnt + 1
-    assert(qstats.fetched_object_cnt <= fetched_object_cnt_max,
-        ('fetched object count (%d) exceeds fetched_object_cnt_max limit (%d)')
-        :format(qstats.fetched_object_cnt, fetched_object_cnt_max))
-    assert(qcontext.deadline_clock > clock.monotonic64(),
-       ('query execution timeout exceeded timeout_ms limit (%s ms)'):format(
-       tostring(self.settings.timeout_ms)))
+    if qstats.fetched_object_cnt > fetched_object_cnt_max then
+        error(e.fetched_objects_limit_exceeded(
+            ('fetched objects count (%d) exceeds fetched_object_cnt_max ' ..
+            'limit (%d)'):format(qstats.fetched_object_cnt,
+            fetched_object_cnt_max)))
+    end
+    if clock.monotonic64() > qcontext.deadline_clock then
+        error(e.timeout_exceeded((
+            'query execution timeout exceeded timeout_ms limit (%s ms)'):format(
+            tostring(self.settings.timeout_ms))))
+    end
     local collection_name = opts.collection_name
     local pcre = opts.pcre
     local resolveField = opts.resolveField
@@ -913,10 +920,12 @@ local function process_tuple(self, state, tuple, opts)
     state.objs[#state.objs + 1] = obj
     state.count = state.count + 1
     qstats.resulting_object_cnt = qstats.resulting_object_cnt + 1
-    assert(qstats.resulting_object_cnt <= resulting_object_cnt_max,
-        ('resulting objects count (%d) exceeds resulting_object_cnt_max ' ..
-        'limit (%d)'):format(qstats.resulting_object_cnt,
-        resulting_object_cnt_max))
+    if qstats.resulting_object_cnt > resulting_object_cnt_max then
+        error(e.resulting_objects_limit_exceeded(
+            ('resulting objects count (%d) exceeds resulting_object_cnt_max ' ..
+            'limit (%d)'):format(qstats.resulting_object_cnt,
+            resulting_object_cnt_max)))
+    end
     if limit ~= nil and state.count >= limit then
         return false
     end

graphql/error_codes.lua

@@ -2,23 +2,42 @@ local error_codes = {}
 
 error_codes.TYPE_MISMATCH = 1
 error_codes.WRONG_VALUE = 2
+error_codes.TIMEOUT_EXCEEDED = 3
+error_codes.FETCHED_OBJECTS_LIMIT_EXCEEDED = 4
+error_codes.RESULTING_OBJECTS_LIMIT_EXCEEDED = 5
 
-function error_codes.type_mismatch(message)
+local function message_and_error_code_error(message, error_code)
     return {
         message = message,
         extensions = {
-            error_code = error_codes.TYPE_MISMATCH,
+            error_code = error_code,
         }
     }
 end
 
+function error_codes.type_mismatch(message)
+    local error_code = error_codes.TYPE_MISMATCH
+    return message_and_error_code_error(message, error_code)
+end
+
 function error_codes.wrong_value(message)
-    return {
-        message = message,
-        extensions = {
-            error_code = error_codes.WRONG_VALUE,
-        }
-    }
+    local error_code = error_codes.WRONG_VALUE
+    return message_and_error_code_error(message, error_code)
+end
+
+function error_codes.timeout_exceeded(message)
+    local error_code = error_codes.TIMEOUT_EXCEEDED
+    return message_and_error_code_error(message, error_code)
+end
+
+function error_codes.fetched_objects_limit_exceeded(message)
+    local error_code = error_codes.FETCHED_OBJECTS_LIMIT_EXCEEDED
+    return message_and_error_code_error(message, error_code)
+end
+
+function error_codes.resulting_objects_limit_exceeded(message)
+    local error_code = error_codes.RESULTING_OBJECTS_LIMIT_EXCEEDED
+    return message_and_error_code_error(message, error_code)
 end
 
 return error_codes

test/common/limit_result.test.lua

@@ -9,6 +9,9 @@ package.path = fio.abspath(debug.getinfo(1).source:match("@?(.*/)")
 local tap = require('tap')
 local test_utils = require('test.test_utils')
 local testdata = require('test.testdata.user_order_item_testdata')
+local graphql = require('graphql')
+
+local e = graphql.error_codes
 
 local function run_queries(gql_wrapper)
     local test = tap.test('result cnt')
@@ -36,10 +39,12 @@ local function run_queries(gql_wrapper)
     local result = gql_query:execute(variables)
     assert(result.data == nil, "this test should fail")
     assert(result.errors ~= nil, "this test should fail")
+    local exp_err = 'resulting objects count (4) exceeds ' ..
+        'resulting_object_cnt_max limit (3)'
     local err = result.errors[1].message
-    test:is(err,
-        'resulting objects count (4) exceeds resulting_object_cnt_max ' ..
-        'limit (3)', 'resulting_object_cnt_max test')
+    local code = result.errors[1].extensions.error_code
+    test:is_deeply({err, code}, {exp_err, e.RESULTING_OBJECTS_LIMIT_EXCEEDED},
+        'resulting_object_cnt_max test')
 
     variables = {
         user_id = 5,
@@ -48,9 +53,11 @@ local function run_queries(gql_wrapper)
     local result = gql_query:execute(variables)
     assert(result.data == nil, "this test should fail")
     assert(result.errors ~= nil, "this test should fail")
+    local exp_err = 'fetched objects count (6) exceeds ' ..
+        'fetched_object_cnt_max limit (5)'
     local err = result.errors[1].message
-    test:is(err,
-        'fetched object count (6) exceeds fetched_object_cnt_max limit (5)',
+    local code = result.errors[1].extensions.error_code
+    test:is_deeply({err, code}, {exp_err, e.FETCHED_OBJECTS_LIMIT_EXCEEDED},
         'fetched_object_cnt_max test')
 
     assert(test:check(), 'check plan')

test/common/query_timeout.test.lua

@@ -9,6 +9,9 @@ package.path = fio.abspath(debug.getinfo(1).source:match("@?(.*/)")
 local tap = require('tap')
 local test_utils = require('test.test_utils')
 local testdata = require('test.testdata.user_order_item_testdata')
+local graphql = require('graphql')
+
+local e = graphql.error_codes
 
 local function run_queries(gql_wrapper)
     local test = tap.test('result cnt')
@@ -34,9 +37,10 @@ local function run_queries(gql_wrapper)
     local result = gql_query:execute(variables)
     assert(result.data == nil, "this test should fail")
     assert(result.errors ~= nil, "this test should fail")
+    local exp_err = 'query execution timeout exceeded timeout_ms limit (0.001 ms)'
     local err = result.errors[1].message
-    test:is(err, 'query execution timeout exceeded timeout_ms limit (0.001 ms)',
-        'timeout test')
+    local code = result.errors[1].extensions.error_code
+    test:is_deeply({err, code}, {exp_err, e.TIMEOUT_EXCEEDED}, 'timeout test')
 
     assert(test:check(), 'check plan')
 end