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Fixes to TypeScript asset-transfer-events to match Go sample (#619)

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Changed:
- Console output formatting
- Transaction arguments
- Readability and comments of code
- Linting rules
- Missing semicolons
- Package name and descrption

Signed-off-by: Mark S. Lewis <mark_lewis@uk.ibm.com>
This commit is contained in:
Mark S. Lewis 2022-02-03 15:13:54 +00:00 committed by GitHub
parent 975c9773bd
commit a492d7d241
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GPG key ID: 4AEE18F83AFDEB23
3 changed files with 48 additions and 76 deletions
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9
asset-transfer-events/application-gateway-typescript/.eslintrc.json
View file

@ -1,7 +1,7 @@
{
"env": {
"node": true,
"es6": true
"es2020": true
},
"root": true,
"ignorePatterns": [
@ -30,15 +30,16 @@
"sourceType": "module",
"ecmaFeatures": {
"impliedStrict": true
}
},
"project": "./tsconfig.json"
},
"plugins": [
"@typescript-eslint"
],
"extends": [
"eslint:recommended",
"plugin:@typescript-eslint/eslint-recommended",
"plugin:@typescript-eslint/recommended"
"plugin:@typescript-eslint/recommended",
"plugin:@typescript-eslint/recommended-requiring-type-checking"
]
}
]

4
asset-transfer-events/application-gateway-typescript/package.json
View file

@ -1,7 +1,7 @@
{
"name": "asset-transfer-basic",
"name": "asset-transfer-events",
"version": "1.0.0",
"description": "Asset Transfer Basic Application implemented in typeScript using fabric-gateway",
"description": "Asset Transfer Events Application implemented in typeScript using fabric-gateway",
"main": "dist/index.js",
"typings": "dist/index.d.ts",
"engines": {

111
asset-transfer-events/application-gateway-typescript/src/app.ts
View file

@ -7,7 +7,6 @@
import * as grpc from '@grpc/grpc-js';
import { ChaincodeEvent, CloseableAsyncIterable, connect, Contract, GatewayError, Network } from '@hyperledger/fabric-gateway';
import { TextDecoder } from 'util';
import { newGrpcConnection, newIdentity, newSigner } from './connect';
const channelName = 'mychannel';
@ -19,9 +18,7 @@ const assetId = `asset${now}`;
async function main(): Promise<void> {
// The gRPC client connection should be shared by all Gateway connections to this endpoint.
const client = await newGrpcConnection();
const gateway = connect({
client,
identity: await newIdentity(),
@ -43,30 +40,19 @@ async function main(): Promise<void> {
let events: CloseableAsyncIterable<ChaincodeEvent> | undefined;
try {
// Get a network instance representing the channel where the smart contract is deployed.
const network = gateway.getNetwork(channelName);
// Get the smart contract from the network.
const contract = network.getContract(chaincodeName);
//Start Listening to events.
// Listen for events emitted by subsequent transactions
events = await startEventListening(network);
// Create a new asset on the ledger.
const firstBlockNumber = await createAsset(contract);
// Update an existing asset.
await updateAsset(contract)
// Transfer an existing asset.
await updateAsset(contract);
await transferAsset(contract);
// Delete asset by assetID.
await deleteAssetByID(contract);
// Replay all the events received.
await replayChaincodeEvents(network,firstBlockNumber)
// Replay events from the block containing the first transaction
await replayChaincodeEvents(network,firstBlockNumber);
} finally {
events?.close();
gateway.close();
@ -79,106 +65,91 @@ main().catch(error => {
process.exitCode = 1;
});
/**
* Start listening to events.
*/
async function startEventListening(network: Network): Promise<CloseableAsyncIterable<ChaincodeEvent>> {
console.log('\n*** Start chaincode event listening\n');
console.log('\n*** Start chaincode event listening');
const events = await network.getChaincodeEvents(chaincodeName);
readEvents(events);
void readEvents(events); // Don't await - run asynchronously
return events;
}
/**
* Read events.
*/
async function readEvents(events: CloseableAsyncIterable<ChaincodeEvent>): Promise<void> {
try {
for await (const event of events) {
const payload = utf8Decoder.decode(event.payload);
console.log(`\n<-- Chaincode event received, name: ${event.eventName}, payload: ${payload}, txID: ${event.transactionId}, blockNumber:${event.blockNumber}`);
const payload = parseJson(event.payload);
console.log(`\n<-- Chaincode event received: ${event.eventName} -`, payload);
}
} catch (error: unknown) {
// Ignore the read error when events.close() is called explicitly
if (!(error instanceof GatewayError) || error.code !== grpc.status.CANCELLED) {
throw error;
}
}
}
/**
* Submit a transaction asynchronously to create a new asset.
*/
async function createAsset(contract: Contract): Promise<bigint> {
console.log(`\n --> Submit Transaction: CreateAsset, creates ${assetId} owned by Tom with appraised value 100`);
function parseJson(jsonBytes: Uint8Array): unknown {
const json = utf8Decoder.decode(jsonBytes);
return JSON.parse(json);
}
const result = await contract.submitAsync('CreateAsset',
{arguments: [assetId,'yellow','5','Tom','100',]});
async function createAsset(contract: Contract): Promise<bigint> {
console.log(`\n--> Submit Transaction: CreateAsset, ${assetId} owned by Sam with appraised value 100`);
const result = await contract.submitAsync('CreateAsset', {
arguments: [ assetId, 'blue', '10', 'Sam', '100' ],
});
const status = await result.getStatus();
if (!status.successful) {
throw new Error(`failed to commit transaction ${status.transactionId} with status code ${status.code}`);
}
console.log('\n*** CreateAsset committed successfully\n')
console.log('\n*** CreateAsset committed successfully');
return status.blockNumber;
}
/**
* Submit transaction synchronously, to updateAsset the asset appraised value.
*/
async function updateAsset(contract: Contract): Promise<void> {
console.log(`\n--> Submit transaction: UpdateAsset, ${assetId} update appraised value to 200`);
await contract.submitTransaction('UpdateAsset',
assetId,'yellow','5','Tom','200',);
await contract.submitTransaction('UpdateAsset', assetId, 'blue', '10', 'Sam', '200');
console.log('\n*** UpdateAsset committed successfully\n')
console.log('\n*** UpdateAsset committed successfully');
}
/**
* Submit transaction synchronously, to transfer the asset.
*/
async function transferAsset(contract: Contract): Promise<void> {
console.log(`\n--> Submit transaction: TransferAsset, ${assetId} to Saptha\n`);
console.log(`\n--> Submit transaction: TransferAsset, ${assetId} to Mary`);
await contract.submitTransaction('TransferAsset',
assetId, 'Saptha',);
await contract.submitTransaction('TransferAsset', assetId, 'Mary');
console.log('\n*** TransferAsset committed successfully\n')
console.log('\n*** TransferAsset committed successfully');
}
/**
* Submit a transaction synchronously to delete an asset by ID.
*/
async function deleteAssetByID(contract:Contract): Promise<void>{
console.log(`\n--> Submit transaction: DeleteAsset ${assetId}`);
async function deleteAssetByID(contract: Contract): Promise<void>{
console.log(`\n--> Submit transaction: DeleteAsset, ${assetId}`);
await contract.submitTransaction('DeleteAsset',
assetId
);
await contract.submitTransaction('DeleteAsset', assetId);
console.log('\n*** DeleteAsset committed successfully\n')
console.log('\n*** DeleteAsset committed successfully');
}
/**
* Replay all the events from the start block.
*/
async function replayChaincodeEvents(network:Network,startBlock:bigint):Promise<void>{
async function replayChaincodeEvents(network: Network, startBlock: bigint): Promise<void>{
const events = await network.getChaincodeEvents(chaincodeName, {
startBlock
startBlock,
});
try {
for await (const event of events) {
const payload = utf8Decoder.decode(event.payload);
console.log(`<-- Chaincode event replayed: ${event.eventName}, payload: ${payload}`);
if(event.eventName === 'DeleteAsset'){
break
const payload = parseJson(event.payload);
console.log(`\n<-- Chaincode event replayed: ${event.eventName} -`, payload);
if (event.eventName === 'DeleteAsset') {
break;
}
}
}finally {
events.close()
} finally {
events.close();
}
}
}