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just started learning blockchain through IBM blockchain platform at VS code and facing issues with the code. I did everything according to the tutorial and had no clue how to resolve them.

Here is the code

/*
 * SPDX-License-Identifier: Apache-2.0
 */

import { Context, Contract, Info, Returns, Transaction } from 'fabric-contract-api';
import { MyAsset } from './my-asset';

@Info({title: 'MyAssetContract', description: 'My Smart Contract' })
export class MyAssetContract extends Contract {

    @Transaction(false)
    @Returns('boolean')
    public async myAssetExists(ctx: Context, myAssetId: string): Promise<boolean> {
        const data: Uint8Array = await ctx.stub.getState(myAssetId);
        return (!!data && data.length > 0);
    }

    @Transaction()
    public async createMyAsset(ctx: Context, myAssetId: string, value: string): Promise<void> {
        const exists: boolean = await this.myAssetExists(ctx, myAssetId);
        if (exists) {
            throw new Error(`The my asset ${myAssetId} already exists`);
        }
        const myAsset: MyAsset = new MyAsset();
        myAsset.value = value;
        const buffer: Buffer = Buffer.from(JSON.stringify(myAsset));
        await ctx.stub.putState(myAssetId, buffer);
    }

    @Transaction(false)
    @Returns('MyAsset')
    public async readMyAsset(ctx: Context, myAssetId: string): Promise<MyAsset> {
        const exists: boolean = await this.myAssetExists(ctx, myAssetId);
        if (!exists) {
            throw new Error(`The my asset ${myAssetId} does not exist`);
        }
        const data: Uint8Array = await ctx.stub.getState(myAssetId);
        const myAsset: MyAsset = JSON.parse(data.toString()) as MyAsset;
        return myAsset;
    }

    @Transaction()
    public async updateMyAsset(ctx: Context, myAssetId: string, newValue: string): Promise<void> {
        const exists: boolean = await this.myAssetExists(ctx, myAssetId);
        if (!exists) {
            throw new Error(`The my asset ${myAssetId} does not exist`);
        }
        const myAsset: MyAsset = new MyAsset();
        myAsset.value = newValue;
        const buffer: Buffer = Buffer.from(JSON.stringify(myAsset));
        await ctx.stub.putState(myAssetId, buffer);
    }

    @Transaction()
    public async deleteMyAsset(ctx: Context, myAssetId: string): Promise<void> {
        const exists: boolean = await this.myAssetExists(ctx, myAssetId);
        if (!exists) {
            throw new Error(`The my asset ${myAssetId} does not exist`);
        }
        await ctx.stub.deleteState(myAssetId);
    }

}

Error 1 enter image description here

Error 2 enter image description here

Error 3 enter image description here

Error 4 enter image description here

Error 5 enter image description here

John Conde
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Rishabh V
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  • looks like you have to run npm install on your project. So open a terminal and go to the directory where your project is (it will have package.json file) and run the command `npm install` – david_k May 31 '21 at 15:56
  • Hi @david_k tried command npm install still getting the below error npm : The term 'npm' is not recognized as the name of a cmdlet, function, script file, or operable program. Check the spelling of the name, or if a path was included, verify that the path is correct and try again. At line:1 char:1 + npm install + ~~~ + CategoryInfo : ObjectNotFound: (npm:String) [], CommandNotFoundException + FullyQualifiedErrorId : CommandNotFoundException – Rishabh V Jun 01 '21 at 06:38
  • Looks like either you don't have Node.js installed or it's not on your PATH – david_k Jun 01 '21 at 08:32

0 Answers0