06_serialize_custom_data_II

🛹 Demo 6: Serializing Custom Data with PDA II

tl; dr

• In this demo we build a chat dApp that lets people submit their introduction and have it stored on Solana’s network.

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Setup

• Run npm install --force from the root of the project.
• Install Phantom Wallet.

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The Buffer Layout

• Many components from this demo are similar to the previous.

• However, in this example, we create the instruction buffer layout in models/StudentIntro.ts, and the program expects instruction data to contain:

  • variant as an unsigned, 8-bit integer representing the instruction to run (should be 0)
  • name as a string representing a name
  • message as a string representing the message

import * as borsh from '@project-serum/borsh'

export class StudentIntro {
    name: string;
    message: string;

    constructor(name: string, message: string) {
        this.name = name;
        this.message = message;
    }

    static mocks: StudentIntro[] = [
        new StudentIntro('Elizabeth Holmes', `Learning Solana so I can use it to build sick NFT projects.`),
        new StudentIntro('Jack Nicholson', `I want to overhaul the world's financial system. Lower friction payments/transfer, lower fees, faster payouts, better collateralization for loans, etc.`),
        new StudentIntro('Terminator', `i'm basically here to protect`),
    ]

    borshInstructionSchema = borsh.struct([
        borsh.u8('variant'),
        borsh.str('name'),
        borsh.str('message'),
    ])

    static borshAccountSchema = borsh.struct([
        borsh.bool('initialized'),
        borsh.str('name'),
        borsh.str('message'),
    ])

    serialize(): Buffer {
        const buffer = Buffer.alloc(1000)
        this.borshInstructionSchema.encode({ ...this, variant: 0 }, buffer)
        return buffer.slice(0, this.borshInstructionSchema.getSpan(buffer))
    }

    static deserialize(buffer?: Buffer): StudentIntro|null {
        if (!buffer) {
            return null
        }

        try {
            const { name, message } = this.borshAccountSchema.decode(buffer)
            return new StudentIntro(name, message)
        } catch(e) {
            console.log('Deserialization error:', e)
            return null
        }
    }
}

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Running

• To check the final dApp, change the settings of your Phantom wallet to "devnet" and then run:

npm run dev

• Open your browser at localhost:3000 and submit an introduction

• Check the transaction at the Solana Explorer.

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References

• Soldev Courses