feat(exit): emit signed exit transfer tx details before signing an exit message

index.d.ts

@@ -10,6 +10,7 @@ declare module "leap-core" {
   import Web3 from 'web3';
   import { Callback } from 'web3/types';
   import { Transaction } from 'web3/eth/types';
+  import PromiEvent from 'web3/promiEvent';
   import { BigIntType } from 'jsbi-utils';
 
   export enum Type {
@@ -317,6 +318,13 @@ declare module "leap-core" {
     }>;
   }
 
+  export type FastSellRequest = {
+    tx: Transaction;
+    sigHashBuff: Buffer;
+    effectiveBlock: number;
+    signedData?: Array<string>;
+  };
+
   type SpendCondSimResult = {
     error?: string;
     outputs: Output[];
@@ -369,17 +377,24 @@ declare module "leap-core" {
       amount: BigIntType | number,
       color: number,
       plasmaChain: ExtendedWeb3,
-      rootChain: ExtendedWeb3,
+      rootChain: Web3,
       marketMakerUrl: string,
-      signer: Signer,
-    ): Promise<any>;
+      signer?: Signer,
+    ): PromiEvent<any>;
 
     static fastSellUTXO(
       utxo: Unspent,
       plasmaChain: ExtendedWeb3,
-      rootChain: ExtendedWeb3,
+      rootChain: Web3,
+      marketMakerUrl: string,
+      signer?: Signer,
+    ): PromiEvent<any>;
+
+    static signAndSendFastSellRequest(
+      fastSellRequest: FastSellRequest,
+      rootChain: Web3,
       marketMakerUrl: string,
-      signer: Signer,
-    ): Promise<any>;
+      signer?: Signer,
+    ): PromiEvent<any>;
   }
 }

lib/exit.js

@@ -1,12 +1,14 @@
 import util from 'ethereumjs-util';
 import { bi } from 'jsbi-utils';
 import fetch from 'node-fetch';
+import Web3PromiEvent from 'web3-core-promievent';
 
 import Tx from './transaction';
 import Outpoint from './outpoint';
 import Output from './output';
 import Input from './input';
-import { periodBlockRange, sendSignedTransaction } from './helpers';
+import Period from './period';
+import { sendSignedTransaction } from './helpers';
 
 
 export default class Exit {
@@ -79,58 +81,70 @@ export default class Exit {
   }
 
   static fastSellUTXO(utxo, plasmaChain, rootChain, marketMakerUrl, signer) {
-    return plasmaChain.getConfig().then(nodeConfig => {
+    const promiEvent = Web3PromiEvent();
+    plasmaChain.getConfig().then(nodeConfig => {
       const inputs = [new Input(utxo.outpoint)];
       const outputs = [
         new Output(utxo.output.value, nodeConfig.exitHandlerAddr, utxo.output.color)
       ];
       const exitingUtxoTransfer = Tx.transfer(inputs, outputs);
-      return Exit.fastSell(exitingUtxoTransfer, plasmaChain, rootChain, marketMakerUrl, signer);
-    })
+      return Exit.fastSell(exitingUtxoTransfer, plasmaChain, rootChain, marketMakerUrl, promiEvent, signer);
+    });
+    return promiEvent.eventEmitter;
   }
 
   static fastSellAmount(account, amount, color, plasmaChain, rootChain, marketMakerUrl, signer) {
-    return Promise.all([plasmaChain.getUnspent(account, color), plasmaChain.getConfig()]).then(([unspent, nodeConfig]) => {
+    const promiEvent = Web3PromiEvent();
+    Promise.all([plasmaChain.getUnspent(account, color), plasmaChain.getConfig()]).then(([unspent, nodeConfig]) => {
       const exitingUtxoTransfer = Tx.transferFromUtxos(
         unspent, account, nodeConfig.exitHandlerAddr, amount, color,
       );
-      return Exit.fastSell(exitingUtxoTransfer, plasmaChain, rootChain, marketMakerUrl, signer);
+      return Exit.fastSell(exitingUtxoTransfer, plasmaChain, rootChain, marketMakerUrl, promiEvent, signer);
     });
+    return promiEvent.eventEmitter;
   }
 
-  static fastSell(spendTx, plasmaChain, rootChain, marketMakerUrl, signer) {
+  static fastSell(spendTx, plasmaChain, rootChain, marketMakerUrl, _promiEvent, signer) {
     const amount = bi(spendTx.outputs[0].value);
+    const fastSellRequest = {};
+    const promiEvent = _promiEvent || Web3PromiEvent();
+    (signer
+        ? signer.signTx(spendTx)
+        : spendTx.signWeb3(rootChain)
+      ).then(signedTx => sendSignedTransaction(plasmaChain, signedTx.hex())
+      ).then(transferTx => {
+        const tx = Tx.fromRaw(transferTx.raw);
+        const utxoId = (new Outpoint(tx.hash(), 0)).getUtxoId();
+        const sigHashBuff = Exit.sigHashBuff(utxoId, amount);
 
-    return (signer
-      ? signer.signTx(spendTx)
-      : spendTx.signWeb3(rootChain)
-    ).then(signedTx => sendSignedTransaction(plasmaChain, signedTx.hex())
-    ).then(transferTx => {
-      const tx = Tx.fromRaw(transferTx.raw);
-      const utxoId = (new Outpoint(tx.hash(), 0)).getUtxoId();
-      const sigHashBuff = Exit.sigHashBuff(utxoId, amount);
-      const sigHash = `0x${sigHashBuff.toString('hex')}`;
-
-      return Promise.all([
-        plasmaChain.eth.getTransaction(
+        fastSellRequest.tx = transferTx;
+        fastSellRequest.sigHashBuff = sigHashBuff;
+        [,fastSellRequest.effectiveBlock] = Period.periodBlockRange(transferTx.blockNumber);
+
+        return plasmaChain.eth.getTransaction(
           util.bufferToHex(tx.inputs[0].prevout.hash)
-        ),
-        signer
-        ? signer.signMessage(sigHash)
-        : Tx.signMessageWithWeb3(rootChain, sigHash)
-      ])
-      .then(([inputTx, sig]) => {
+        );
+      }).then((inputTx) => {
+        fastSellRequest.inputTx = inputTx;
+        promiEvent.eventEmitter.emit('transfer', fastSellRequest);
+        return Exit.signAndSendFastSellRequest(fastSellRequest, rootChain, marketMakerUrl, signer);
+      }).then(promiEvent.resolve)
+      .catch(promiEvent.reject);
+    return promiEvent.eventEmitter;
+  }
+
+  static signAndSendFastSellRequest(fastSellRequest, rootChain, marketMakerUrl, signer) {
+    const sigHash = `0x${fastSellRequest.sigHashBuff.toString('hex')}`;
+    return (signer
+      ? signer.signMessage(sigHash)
+      : Tx.signMessageWithWeb3(rootChain, sigHash))
+      .then((sig) => {
         const vBuff = Buffer.alloc(32);
         vBuff.writeInt8(sig.v, 31);
         const signedData = Exit.bufferToBytes32Array(
-          Buffer.concat([sigHashBuff, Buffer.from(sig.r), Buffer.from(sig.s), vBuff])
+          Buffer.concat([fastSellRequest.sigHashBuff, Buffer.from(sig.r), Buffer.from(sig.s), vBuff])
         );
-        const setup = {
-          inputTx,
-          tx: transferTx,
-          effectiveBlock: periodBlockRange(transferTx.blockNumber)[1],
-          signedData
-        };
+        fastSellRequest.signedData = signedData;
 
         return fetch(
           marketMakerUrl,
@@ -141,10 +155,10 @@ export default class Exit {
             headers: {
                 "Content-Type": "application/json",
             },
-            body: JSON.stringify(setup),
+            body: JSON.stringify(fastSellRequest),
           }
-        ).then(response => response.json());
-      })
-    });
+        )
+        .then(response => response.json());
+      });
   }
 }

package.json

@@ -73,6 +73,7 @@
     "@types/web3": "^1.0.18",
     "ethereumjs-util": "6.0.0",
     "jsbi-utils": "^1.0.0",
-    "node-fetch": "^2.3.0"
+    "node-fetch": "^2.3.0",
+    "web3-core-promievent": "^1.2.4"
   }
 }

yarn.lock

@@ -1015,6 +1015,11 @@ ansi-to-html@^0.6.4:
   dependencies:
     entities "^1.1.1"
 
+any-promise@1.3.0:
+  version "1.3.0"
+  resolved "https://registry.yarnpkg.com/any-promise/-/any-promise-1.3.0.tgz#abc6afeedcea52e809cdc0376aed3ce39635d17f"
+  integrity sha1-q8av7tzqUugJzcA3au0845Y10X8=
+
 anymatch@^2.0.0:
   version "2.0.0"
   resolved "https://registry.yarnpkg.com/anymatch/-/anymatch-2.0.0.tgz#bcb24b4f37934d9aa7ac17b4adaf89e7c76ef2eb"
@@ -2445,6 +2450,11 @@ ethjs-util@^0.1.6:
     is-hex-prefixed "1.0.0"
     strip-hex-prefix "1.0.0"
 
+eventemitter3@3.1.2:
+  version "3.1.2"
+  resolved "https://registry.yarnpkg.com/eventemitter3/-/eventemitter3-3.1.2.tgz#2d3d48f9c346698fce83a85d7d664e98535df6e7"
+  integrity sha512-tvtQIeLVHjDkJYnzf2dgVMxfuSGJeM/7UCG17TT4EumTfNtF+0nebF/4zWOIkCreAbtNqhGEboB6BWrwqNaw4Q==
+
 events@^3.0.0:
   version "3.0.0"
   resolved "https://registry.yarnpkg.com/events/-/events-3.0.0.tgz#9a0a0dfaf62893d92b875b8f2698ca4114973e88"
@@ -5975,6 +5985,14 @@ wcwidth@^1.0.1:
   dependencies:
     defaults "^1.0.3"
 
+web3-core-promievent@^1.2.4:
+  version "1.2.4"
+  resolved "https://registry.yarnpkg.com/web3-core-promievent/-/web3-core-promievent-1.2.4.tgz#75e5c0f2940028722cdd21ba503ebd65272df6cb"
+  integrity sha512-gEUlm27DewUsfUgC3T8AxkKi8Ecx+e+ZCaunB7X4Qk3i9F4C+5PSMGguolrShZ7Zb6717k79Y86f3A00O0VAZw==
+  dependencies:
+    any-promise "1.3.0"
+    eventemitter3 "3.1.2"
+
 webidl-conversions@^4.0.2:
   version "4.0.2"
   resolved "https://registry.yarnpkg.com/webidl-conversions/-/webidl-conversions-4.0.2.tgz#a855980b1f0b6b359ba1d5d9fb39ae941faa63ad"