Add BigInt and BigDecimal GraphQL scalars (#452)

packages/codegen/src/templates/package-template.handlebars

@@ -49,7 +49,6 @@
     "@cerc-io/graph-node": "^0.2.67",
     {{/if}}
     "@ethersproject/providers": "^5.4.4",
-    "apollo-type-bigint": "^0.1.3",
     "debug": "^4.3.1",
     "decimal.js": "^10.3.1",
     "ethers": "^5.4.4",

packages/codegen/src/templates/resolvers-template.handlebars

@@ -3,13 +3,8 @@
 //
 
 import assert from 'assert';
-import BigInt from 'apollo-type-bigint';
 import debug from 'debug';
-import Decimal from 'decimal.js';
-import {
-  GraphQLScalarType,
-  GraphQLResolveInfo
-} from 'graphql';
+import { GraphQLResolveInfo } from 'graphql';
 
 import {
   {{#if queries}}
@@ -19,6 +14,8 @@ import {
   gqlQueryCount,
   getResultState,
   IndexerInterface,
+  GraphQLBigInt,
+  GraphQLBigDecimal,
   {{#if (subgraphPath)}}
   BlockHeight,
   jsonBigIntStringReplacer,
@@ -45,20 +42,9 @@ export const createResolvers = async (indexerArg: IndexerInterface, eventWatcher
   const gqlCacheConfig = indexer.serverConfig.gqlCache;
 
   return {
-    BigInt: new BigInt('bigInt'),
+    BigInt: GraphQLBigInt,
 
-    BigDecimal: new GraphQLScalarType({
-      name: 'BigDecimal',
-      description: 'BigDecimal custom scalar type',
-      parseValue (value) {
-        // value from the client
-        return new Decimal(value);
-      },
-      serialize (value: Decimal) {
-        // value sent to the client
-        return value.toFixed();
-      }
-    }),
+    BigDecimal: GraphQLBigDecimal,
 
     Event: {
       __resolveType: (obj: any) => {

packages/util/package.json

@@ -21,6 +21,7 @@
     "apollo-server-core": "^3.11.1",
     "apollo-server-express": "^3.11.1",
     "apollo-server-plugin-response-cache": "^3.8.1",
+    "apollo-type-bigint": "^0.1.3",
     "bunyan": "^1.8.15",
     "debug": "^4.3.1",
     "decimal.js": "^10.3.1",

packages/util/src/misc.ts

@@ -9,7 +9,8 @@ import { hideBin } from 'yargs/helpers';
 import { utils, providers } from 'ethers';
 import JSONbig from 'json-bigint';
 import Decimal from 'decimal.js';
-import { GraphQLResolveInfo } from 'graphql';
+import ApolloBigInt from 'apollo-type-bigint';
+import { GraphQLResolveInfo, GraphQLScalarType, ValueNode } from 'graphql';
 import _ from 'lodash';
 
 import { DEFAULT_CONFIG_PATH } from './constants';
@@ -305,3 +306,55 @@ export const setGQLCacheHints = (info: GraphQLResolveInfo, block: BlockHeight, g
 
   info.cacheControl.setCacheHint({ maxAge });
 };
+
+class GraphQLBigIntType extends ApolloBigInt {
+  constructor () {
+    super('bigInt');
+  }
+
+  name = 'BigInt';
+  description = 'BigInt custom scalar type';
+
+  parseLiteral = function (ast: ValueNode) {
+    if (ast.kind === 'IntValue' || ast.kind === 'StringValue') {
+      return global.BigInt(ast.value);
+    } else {
+      throw new TypeError(`BigInt cannot represent value kind: ${ast.kind}`);
+    }
+  };
+
+  parseValue = function (value: any) {
+    if (value === '') {
+      throw new TypeError('The value cannot be converted from BigInt because it is empty string');
+    }
+
+    if (typeof value !== 'number' && typeof value !== 'bigint' && typeof value !== 'string') {
+      throw new TypeError(
+        `The value ${value} cannot be converted to a BigInt because it is not an integer`
+      );
+    }
+
+    try {
+      return global.BigInt(value);
+    } catch {
+      throw new TypeError(
+        `The value ${value} cannot be converted to a BigInt because it is not an integer`
+      );
+    }
+  };
+}
+
+export const GraphQLBigInt = new GraphQLBigIntType();
+
+export const GraphQLBigDecimal = new GraphQLScalarType({
+  name: 'BigDecimal',
+  description: 'BigDecimal custom scalar type',
+  parseValue (value) {
+    // value from the client
+    return new Decimal(value);
+  },
+  serialize (value: Decimal) {
+    // value sent to the client
+    return value.toFixed();
+  }
+});

yarn.lock

@@ -4703,6 +4703,11 @@ apollo-server-types@^3.8.0:
     apollo-reporting-protobuf "^3.4.0"
     apollo-server-env "^4.2.1"
 
+apollo-type-bigint@^0.1.3:
+  version "0.1.3"
+  resolved "https://registry.yarnpkg.com/apollo-type-bigint/-/apollo-type-bigint-0.1.3.tgz#9242115ca909b9467ba5c4bc6493a56a06984c0b"
+  integrity sha512-nyfwEWRZ+kon3Nnot20DufGm2EHZrkJoryYzw3soD+USdxhkcW434w1c/n+mjMLQDl86Z6EvlkvMX5Lordf2Wg==
+
 app-root-path@^3.0.0:
   version "3.0.0"
   resolved "https://registry.npmjs.org/app-root-path/-/app-root-path-3.0.0.tgz"