e-book

flea-market-contract-service.ts

public removePurchaseContract(productKey: string): Observable<string> {

const bytes32Key = utils.formatBytes32String(productKey);
const token = this.contractToken.removeContractByKey(bytes32Key);

return from(token)
  .pipe(
    switchMap((tx: any) => {
    
      console.log('removeContractByKey Transaction', tx);
      // Wait for transaction to be mined
      // Returned a Promise which would resolve to 
      //the TransactionReceipt once it is mined.
      return from(tx.wait()).pipe(
        tap((txReceipt: any) => 
             console.log('TransactionReceipt: ', txReceipt)),

        // The receipt will have an "events" Array, which will have
        // the emitted event from the Contract. 
        // The "LogRemovePurchaseContract(address sender, bytes32 key))
        // call is the last event.
        map(txReceipt => txReceipt.events.pop()),
        tap(txEvent => console.log('txEvent: ', txEvent)),
        map(txEvent => {
          // retrieve the key parameter value from the event
          const key = txEvent.args.key;
          return utils.parseBytes32String(key as ethers.utils.Arrayish);
        }),

      );
    }));
}