Swap tokens on Solana using Jupiter

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This guide uses a complete Python example to demonstrate how to combine Cobo WaaS SDK with Jupiter on Solana, from getting swap routes to submitting an on-chain token swap transaction, so that you can quickly integrate token swap capabilities.

This document is intended for developers who already understand Solana programming and Jupiter routing. Basic blockchain concepts and Jupiter mechanics will not be introduced here.

Prerequisites

Before you begin, ensure the following:

You have followed the steps in Send your first API request and successfully sent an API request.
You understand and can use the Call smart contract API.
You are familiar with Solana smart contract calls and understand the basic concepts and usage of Jupiter.
Your Solana address has sufficient balance, including:
- Enough balance of the token you plan to swap;
- Enough SOL to pay for transaction fees.
Since this guide provides a Python-based example, please ensure your local environment has:
- Python 3.9 or above
- Required packages: cobo_waas2, requests, and solders
This example uses an MPC Wallet (Organization-Controlled Wallet). If you are using a Custodial Wallet (Web3 wallet), make sure to update the source parameter in the Call Smart Contract API request to use the Custodial Wallets (Web3 wallets) structure instead.

Python example

This example walks through:

Getting the best swap route from Jupiter
Generating swap instructions with Jupiter
Parsing Address Lookup Tables (ALT)
Call smart contract
Executing a swap from SOL to USDT

The following code highlights the parameters you must customize (such as API key, wallet ID, address, token pair, and amount). All other code can be used without modification.

import base64
import cobo_waas2
import json
import requests
import uuid

from solders.pubkey import Pubkey


# ========= Jupiter configuration =========
JUPITER_BASE_URL = "https://lite-api.jup.ag/swap/v1/"
SOLANA_RPC = "https://api.mainnet-beta.solana.com"

# Fixed mint addresses for Solana mainnet tokens. Native SOL uses a special system-defined mint address.
SOL_MINT = "So11111111111111111111111111111111111111112"
JLP_MINT = "27G8MtK7VtTcCHkpASjSDdkWWYfoqT6ggEuKidVJidD4"
USDC_MINT = "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v"
USDT_MINT = "Es9vMFrzaCERmJfrF4H2FYD4KCoNkY11McCe8BenwNYB"

COIN_MINT_MAP = {
    'SOL': SOL_MINT,
    'SOL_JLP': JLP_MINT,
    'SOL_USDC': USDC_MINT,
    'SOL_USDT': USDT_MINT,
}
COIN_DECIMALS = {
    SOL_MINT: 9,
    JLP_MINT: 6,
    USDC_MINT: 6,
    USDT_MINT: 6,
}


# ========= Jupiter API section (calling Jupiter quote/swap APIs) =========
def get_jupiter_quote(input_mint, output_mint, amount, slippage_bps=50):
    """
    Request a swap quote from Jupiter.
    Args:
        input_mint: Mint address of the input token
        output_mint: Mint address of the output token
        amount: Swap amount
        slippage_bps: Slippage tolerance
    """
    params = {
        "inputMint": input_mint,
        "outputMint": output_mint,
        "amount": str(amount),
        "slippageBps": str(slippage_bps)
    }
    r = requests.get(JUPITER_BASE_URL + "quote", params=params, verify=False)
    r.raise_for_status()
    return r.json()


def get_swap_instructions(quote, address):
    """
    Generate swap instructions based on a Jupiter quote.
    """
    payload = {
        "quoteResponse": quote,
        "userPublicKey": address,
        "dynamicSlippage": True,
        "useSharedAccounts": True,
        "dynamicComputeUnitLimit": True,
        "wrapAndUnwrapSol": True,
        "skipUserAccountsRpcCalls": False,
    }
    r = requests.post(JUPITER_BASE_URL + "swap-instructions", json=payload, verify=False)
    r.raise_for_status()
    return r.json()


def fetch_address_lookup_table(alt_address):
    """
    Fetch accounts inside the Address Lookup Table (ALT).
    Args:
        alt_address: ALT address
    Returns:
        list: List of addresses inside the ALT
    """
    print(f"  Fetching ALT: {alt_address}")

    payload = {
        "jsonrpc": "2.0",
        "id": 1,
        "method": "getAccountInfo",
        "params": [
            alt_address,
            {"encoding": "base64"}
        ]
    }

    try:
        response = requests.post(SOLANA_RPC, json=payload, verify=False)
        response.raise_for_status()
        result = response.json()

        if "result" not in result or not result["result"] or not result["result"]["value"]:
            print(f"  Warning: Unable to fetch ALT account info: {alt_address}")
            return []

        # Parsing ALT account information
        account_data = result["result"]["value"]["data"][0]
        raw_data = base64.b64decode(account_data)

        # ALT account layout:   
        # - The first 56 bytes are header metadata
        # - Every subsequent 32-byte chunk is a public key inside the lookup table
        addresses = []
        offset = 56  # Skip the header

        while offset + 32 <= len(raw_data):
            pubkey_bytes = raw_data[offset:offset + 32]
            pubkey = Pubkey(pubkey_bytes)
            addresses.append(str(pubkey))
            offset += 32

        print(f"  Found {len(addresses)} accounts in ALT")
        return addresses
    except Exception as e:
        print(f"  ALT fetch failed: {e}")
        return []


# ========= Cobo API section =========
class CoboAPI:
    def __init__(self, api_private_key, host):
        self.api_private_key = api_private_key
        self.host = host

    def get_configuration(self):
        return cobo_waas2.Configuration(
            api_private_key=self.api_private_key,
            host=self.host
        )

    def swap_coin(self, wallet_id, address, input_coin, output_coin, amount):
        """
        Call Cobo WaaS service to execute a Solana contract call for a token swap.
        Args:
            wallet_id: Cobo wallet ID
            address: Solana address
            input_coin: Input token symbol
            output_coin: Output token symbol
            amount: Swap amount
        Returns:
            transaction_id: Transaction ID in Cobo Portal
        """
        print(f"Executing token swap via Cobo WaaS... address={address}, {input_coin} -> {output_coin}, amount={amount}")

        input_mint = COIN_MINT_MAP[input_coin]
        output_mint = COIN_MINT_MAP[output_coin]
        amount = self.to_jupiter_amount(amount, COIN_DECIMALS[input_mint])

        with cobo_waas2.ApiClient(self.get_configuration()) as api_client:
            # 1. Get a quote from Jupiter
            quote = get_jupiter_quote(input_mint, output_mint, amount)

            # 2. Get swap instructions from Jupiter
            instructions_json = get_swap_instructions(quote, address)

            # 3. Build transaction instructions and ALT accounts
            instructions, alt_accounts = self.build_transaction(instructions_json, address)

            # 4. Call Cobo WaaS service to create a contract call transaction
            contract_call_params = cobo_waas2.ContractCallParams(
                request_id=str(uuid.uuid4()),
                chain_id="SOL",
                source=cobo_waas2.ContractCallSource(
                    cobo_waas2.MpcContractCallSource(
                        source_type=cobo_waas2.ContractCallSourceType.ORG_CONTROLLED,
                        wallet_id=wallet_id,
                        address=address,
                    )
                ),
                destination=cobo_waas2.ContractCallDestination(
                    cobo_waas2.SolContractCallDestination(
                        destination_type=cobo_waas2.ContractCallDestinationType.SOL_CONTRACT,
                        instructions=instructions,
                        address_lookup_table_accounts=alt_accounts
                    )
                ),
            )

            print("=================================")
            print("contract call params:", contract_call_params.to_json())
            print("=================================")

            api_instance = cobo_waas2.TransactionsApi(api_client)

            try:
                api_response = api_instance.create_contract_call_transaction(
                    contract_call_params=contract_call_params
                )
                print("contract call response:", api_response)
                return api_response.transaction_id
            except Exception as e:
                print("Error:", e)
                return ""

    @staticmethod
    def build_instruction(ins, address):
        accounts = []
        print("build instruction:", ins.get("programId"), "accounts:", len(ins.get("accounts", [])))
        for acc in ins["accounts"]:
            accounts.append(
                cobo_waas2.SolContractCallAccount(
                    pubkey=acc["pubkey"],
                    is_signer=acc["isSigner"],
                    is_writable=acc["isWritable"] or acc["pubkey"] == address,
                )
            )
        return cobo_waas2.SolContractCallInstruction(
            program_id=ins["programId"],
            accounts=accounts,
            data=ins["data"],
        )

    def build_transaction(self, instructions_json, address):
        print("build transaction:", json.dumps(instructions_json))
        all_instructions = []

        for key in ["computeBudgetInstructions", "setupInstructions"]:
            all_instructions += [self.build_instruction(i, address) for i in instructions_json.get(key, [])]

        if "swapInstruction" in instructions_json and instructions_json["swapInstruction"]:
            all_instructions.append(self.build_instruction(instructions_json["swapInstruction"], address))

        if "cleanupInstruction" in instructions_json and instructions_json["cleanupInstruction"]:
            all_instructions.append(self.build_instruction(instructions_json["cleanupInstruction"], address))

        if "otherInstructions" in instructions_json and instructions_json["otherInstructions"]:
            all_instructions += [self.build_instruction(i, address) for i in instructions_json["otherInstructions"]]

        alt_accounts = []

        if "addressLookupTableAddresses" in instructions_json:
            alt_addresses = instructions_json["addressLookupTableAddresses"]
            for alt_address in alt_addresses:
                addresses = fetch_address_lookup_table(alt_address)
                if addresses:
                    alt_accounts.append(
                        cobo_waas2.SolContractCallAddressLookupTableAccount(
                            alt_account_key=alt_address,
                            addresses=addresses,
                        )
                    )

        return all_instructions, alt_accounts

    @staticmethod
    def to_jupiter_amount(readable_amount, decimals):
        """Convert human-readable amount to Jupiter integer amount."""
        return int(readable_amount * (10 ** decimals))

    @staticmethod
    def to_readable_amount(raw_amount, decimals):
        """Convert Jupiter integer amount to human-readable format."""
        return raw_amount / (10 ** decimals)


if __name__ == "__main__":
    # ======== Parameters you must modify for your own environment (required) ========
    # TODO: Use the development environment. For production environment, change to "https://api.cobo.com/v2".
    cobo_host = "https://api.dev.cobo.com/v2"
    # TODO: Enter your API key
    api_key = ""
    # TODO: Enter your Wallet ID
    mpc_wallet_id = ""
    # TODO: Enter your Solana address, and make sure it has enough SOL and the token to be swapped
    sol_address = ""

    # ======== Example: SOL -> USDT ========
    myCoboApi = CoboAPI(api_key, cobo_host)
    # "SOL" is the token ID of input token, "SOL_USDT" is the token ID of output token (USDT), 0.0001 is the swap amount
    myCoboApi.swap_coin(mpc_wallet_id, sol_address, "SOL", "SOL_USDT", 0.0001)
    # If you want to swap to JLP or USDC, use the following examples:
    # myCoboApi.swap_coin(mpc_wallet_id, sol_address, "SOL", "SOL_JLP", 0.0001)
    # myCoboApi.swap_coin(mpc_wallet_id, sol_address, "SOL", "SOL_USDC", 0.0001)

​Prerequisites

​Python example

Prerequisites

Python example