import * as _ from 'lodash'; import { AsyncMethod, ContractWrappersError, SyncMethod } from '../types'; import { constants } from './constants'; type ErrorTransformer = (err: Error) => Error; const contractCallErrorTransformer = (error: Error) => { if (_.includes(error.message, constants.INVALID_JUMP_PATTERN)) { return new Error(ContractWrappersError.InvalidJump); } if (_.includes(error.message, constants.OUT_OF_GAS_PATTERN)) { return new Error(ContractWrappersError.OutOfGas); } if (_.includes(error.message, constants.REVERT)) { const revertReason = error.message.split(constants.REVERT)[1].trim(); return new Error(revertReason); } return error; }; const schemaErrorTransformer = (error: Error) => { if (_.includes(error.message, constants.INVALID_TAKER_FORMAT)) { const errMsg = 'Order taker must be of type string. If you want anyone to be able to fill an order - pass NULL_ADDRESS'; return new Error(errMsg); } return error; }; const signatureRequestErrorTransformer = (error: Error) => { if (_.includes(error.message, constants.USER_DENIED_SIGNATURE_PATTERN)) { const errMsg = ContractWrappersError.SignatureRequestDenied; return new Error(errMsg); } return error; }; /** * Source: https://stackoverflow.com/a/29837695/3546986 */ const asyncErrorHandlerFactory = (errorTransformer: ErrorTransformer) => { const asyncErrorHandlingDecorator = ( _target: object, _key: string | symbol, descriptor: TypedPropertyDescriptor, ) => { const originalMethod = descriptor.value as AsyncMethod; // Do not use arrow syntax here. Use a function expression in // order to use the correct value of `this` in this method // tslint:disable-next-line:only-arrow-functions descriptor.value = async function(...args: any[]): Promise { try { const result = await originalMethod.apply(this, args); // tslint:disable-line:no-invalid-this return result; } catch (error) { const transformedError = errorTransformer(error); throw transformedError; } }; return descriptor; }; return asyncErrorHandlingDecorator; }; const syncErrorHandlerFactory = (errorTransformer: ErrorTransformer) => { const syncErrorHandlingDecorator = ( _target: object, _key: string | symbol, descriptor: TypedPropertyDescriptor, ) => { const originalMethod = descriptor.value as SyncMethod; // Do not use arrow syntax here. Use a function expression in // order to use the correct value of `this` in this method // tslint:disable-next-line:only-arrow-functions descriptor.value = function(...args: any[]): any { try { const result = originalMethod.apply(this, args); // tslint:disable-line:no-invalid-this return result; } catch (error) { const transformedError = errorTransformer(error); throw transformedError; } }; return descriptor; }; return syncErrorHandlingDecorator; }; // _.flow(f, g) = f ∘ g const zeroExErrorTransformer = _.flow( schemaErrorTransformer, contractCallErrorTransformer, signatureRequestErrorTransformer, ); export const decorators = { asyncZeroExErrorHandler: asyncErrorHandlerFactory(zeroExErrorTransformer), syncZeroExErrorHandler: syncErrorHandlerFactory(zeroExErrorTransformer), };