Serialize float, int, Pubkey data using web3 js

Question

I am trying to pass parameters of types: float, int, bool, pubkey to Solana anchor program instructions from web3js library

#[account]
pub struct Parent {
    pub field1: String,
    pub field2: u8,
    pub field3: f64,
    pub field4: Pubkey,
}

I am using the following approach to serialize a string parameter

// serializing a string parameter
const data = 'sample data';

const string_u8vec = new TextEncoder().encode(data)
const string_u8vec_length = Buffer.from(new Uint8Array(new BN(string_u8vec.length).toArray("le", 4)));

const instructionBuffer = Buffer.concat([
   ixBuffer,            // namespace+method_name
   string_u8vec_length, // the length of the string
   string_u8vec         // the string itself
])

What is the correct way to serialize all other data types mentioned above? And is there a common method to serialize all data types or we should handle each differently?

Please help. Thanks

Answer 1

Each data type is serialized differently into the buffer, but they're all possible.

• For u8, you can do instructionBuffer.writeUInt8(value), be sure to allocate 1 byte for it.
• For f64, you can do instructionBuffer.writeDoubleLE(value), be sure to allocate 8 bytes for it.
• For pubkey, you can do Buffer.concat([instructionBuffer, pubkey.toBuffer()]).

Most of this was taken from the Buffer documentation at https://nodejs.org/api/buffer.html