Change file layout

1 files changed, 81 insertions, 0 deletions

diff --git a/packages/deployer/src/utils/contract.ts b/packages/deployer/src/utils/contract.ts
new file mode 100644
index 000000000..546e82dfb
--- /dev/null
+++ b/packages/deployer/src/utils/contract.ts
@@ -0,0 +1,81 @@
+import { schemas, SchemaValidator } from '@0xproject/json-schemas';
+import { promisify } from '@0xproject/utils';
+import * as _ from 'lodash';
+import * as Web3 from 'web3';
+
+import { AbiType } from './types';
+
+export class Contract implements Web3.ContractInstance {
+    public address: string;
+    public abi: Web3.ContractAbi;
+    private _contract: Web3.ContractInstance;
+    private _defaults: Partial<Web3.TxData>;
+    private _validator: SchemaValidator;
+    // This class instance is going to be populated with functions and events depending on the ABI
+    // and we don't know their types in advance
+    [name: string]: any;
+    constructor(web3ContractInstance: Web3.ContractInstance, defaults: Partial<Web3.TxData>) {
+        this._contract = web3ContractInstance;
+        this.address = web3ContractInstance.address;
+        this.abi = web3ContractInstance.abi;
+        this._defaults = defaults;
+        this._populateEvents();
+        this._populateFunctions();
+        this._validator = new SchemaValidator();
+    }
+    private _populateFunctions(): void {
+        const functionsAbi = _.filter(this.abi, abiPart => abiPart.type === AbiType.Function) as Web3.FunctionAbi[];
+        _.forEach(functionsAbi, (functionAbi: Web3.MethodAbi) => {
+            if (functionAbi.constant) {
+                const cbStyleCallFunction = this._contract[functionAbi.name].call;
+                this[functionAbi.name] = {
+                    callAsync: promisify(cbStyleCallFunction, this._contract),
+                };
+            } else {
+                const cbStyleFunction = this._contract[functionAbi.name];
+                const cbStyleEstimateGasFunction = this._contract[functionAbi.name].estimateGas;
+                this[functionAbi.name] = {
+                    estimateGasAsync: promisify(cbStyleEstimateGasFunction, this._contract),
+                    sendTransactionAsync: this._promisifyWithDefaultParams(cbStyleFunction),
+                };
+            }
+        });
+    }
+    private _populateEvents(): void {
+        const eventsAbi = _.filter(this.abi, abiPart => abiPart.type === AbiType.Event) as Web3.EventAbi[];
+        _.forEach(eventsAbi, (eventAbi: Web3.EventAbi) => {
+            this[eventAbi.name] = this._contract[eventAbi.name];
+        });
+    }
+    private _promisifyWithDefaultParams(fn: (...args: any[]) => void): (...args: any[]) => Promise<any> {
+        const promisifiedWithDefaultParams = async (...args: any[]) => {
+            const promise = new Promise((resolve, reject) => {
+                const lastArg = args[args.length - 1];
+                let txData: Partial<Web3.TxData> = {};
+                if (this._isTxData(lastArg)) {
+                    txData = args.pop();
+                }
+                txData = {
+                    ...this._defaults,
+                    ...txData,
+                };
+                const callback = (err: Error, data: any) => {
+                    if (_.isNull(err)) {
+                        resolve(data);
+                    } else {
+                        reject(err);
+                    }
+                };
+                args.push(txData);
+                args.push(callback);
+                fn.apply(this._contract, args);
+            });
+            return promise;
+        };
+        return promisifiedWithDefaultParams;
+    }
+    private _isTxData(lastArg: any): boolean {
+        const isValid = this._validator.isValid(lastArg, schemas.txDataSchema);
+        return isValid;
+    }
+}