feat: allow to specify period data fallback for getProof helper (#161)

leapdao · Nov 22, 2019 · 090f903 · 090f903
1 parent db3106a
commit 090f903
Show file tree

Hide file tree

Showing 3 changed files with 50 additions and 7 deletions.
diff --git a/index.d.ts b/index.d.ts
@@ -325,9 +325,9 @@ declare module "leap-core" {
   type PeriodData = {
     validatorAddress: string;
     slotId: number;
-    casBitmap: string;
-    periodStart: number;
-    periodEnd: number;
+    casBitmap?: string;
+    periodStart?: number;
+    periodEnd?: number;
   };
 
   class ExtendedWeb3 extends Web3 {
@@ -352,7 +352,7 @@ declare module "leap-core" {
     export function periodBlockRange(blockNumber: number): [number, number];
     export function getTxWithYoungestBlock(txs: LeapTransaction[]): InputTx;
     export function getYoungestInputTx(plasma: ExtendedWeb3, tx: Tx<any>): Promise<InputTx>;
-    export function getProof(plasma: ExtendedWeb3, tx: LeapTransaction): Promise<Proof>;
+    export function getProof(plasma: ExtendedWeb3, tx: LeapTransaction, fallbackPeriodData?: PeriodData): Promise<Proof>;
     // Depending on plasma instance, resolves to either Web3's Transaction or Ethers' TransactionReceipt
     export function sendSignedTransaction(plasma: ExtendedWeb3, tx: string): Promise<any>;
     export function simulateSpendCond(plasma: ExtendedWeb3, tx: Tx<Type.SPEND_COND>): Promise<SpendCondSimResult>;

diff --git a/lib/helpers.js b/lib/helpers.js
@@ -215,15 +215,21 @@ export function getYoungestInputTx(plasma, tx) {
  * @param {LeapTransaction} tx
  * @returns {Promise<Proof>} promise that resolves to period inclusion proof
  */
-export function getProof(plasma, tx) {
+export function getProof(plasma, tx, fallbackPeriodData) {
   return Promise.all([
       Period.periodForTx(plasma, tx),
       plasma.getPeriodByBlockHeight(tx.blockNumber)
     ]).then(([period, periodData]) => {
+      const [periodDataObj] = periodData || [fallbackPeriodData];
       if (!periodData || !periodData.length) {
-        throw new Error(`No period data for the given tx. Height:${tx.blockHeight}`);
+        const msg = `No period data for the given tx. Height: ${tx.blockNumber}`;
+        if (!fallbackPeriodData) {
+          throw new Error(msg);
+        } else {
+          console.warn(msg, 'Using fallback values'); // eslint-disable-line no-console
+        }
       }
-      const { slotId, validatorAddress, casBitmap } = periodData[0];
+      const { slotId, validatorAddress, casBitmap } = periodDataObj;
 
       period.setValidatorData(slotId, validatorAddress, casBitmap);
       return period.proof(Tx.fromRaw(tx.raw));

diff --git a/lib/helpers.spec.js b/lib/helpers.spec.js
@@ -188,6 +188,43 @@ describe('helpers', () => {
       ).to.eventually.throw(`No period data for the given tx. Height:4`);
     });
 
+    it('no period data for the height, with fallback', async () => {
+      const value = 50000000;
+      const color = 1337;
+      const deposit1 = Tx.deposit(0, value, ADDR_1, color);
+
+      const plasma = {
+        getBlock: n => {
+          expect(n).to.be.within(0, 32);
+          const transactions = n === 4 ? [{ raw: deposit1.hex() }] : [];
+          return { number: n, timestamp: 123, transactions };
+        },
+        getPeriodByBlockHeight: () => null,
+      };
+
+      const fallbackData = { slotId: 0, validatorAddress: ADDR_1 };
+
+      const proof = getProof(
+        plasma, 
+        { blockNumber: 4, raw: deposit1.hex() },
+        fallbackData
+      );
+      return expect(proof).to.eventually.eql([ 
+        '0x29aa1b0213471dbf84175e8f688e5a63c2e5724ad6bc581a10b9521f4b8a6083',
+        '0x4404003c00000000000000080000000000000000000000000000000000000000',
+        '0x0000000002110000000000000000000000000000000000000000000000000000',
+        '0x00000000000002faf08005394436373705394267350db2c06613990d34621d69',
+        '0x0000000000000000000000000000000000000000000000000000000000000000',
+        '0x0000000000000000000000000000000000000000000000000000000000000000',
+        '0xad3228b676f7d3cd4284a5443f17f1962b36e491b30a40b2405849e597ba5fb5',
+        '0xb4c11951957c6f8f642c4af61cd6b24640fec6dc7fc607ee8206a99e92410d30',
+        '0x21ddb9a356815c3fac1026b6dec5df3124afbadb485c9ba5a3e3398a04b7ba85',
+        '0xe58769b32a1beaf1ea27375a44095a0d1fb664ce2dd358e7fcbfb78c26a19344',
+        '0x0000000000000000000000000000000000000000000000000000000000000000',
+        '0x99ed61756087b72bef3d352ea237450df3d0749dd2e39615b8f8e993370f4ae9'
+      ]);
+    });
+
     it('should get CAS proof', async () => {
       const value = 50000000;
       const color = 1337;