JSONRPC error on sendSignedTransaction

Question

I run ganache, truffle and metmask. If I run the code below I get an error on the this.web3.eth.sendSignedTransaction() function:

EDIT: changed my code to the following.. Error remained the same though.

    const encoded_tx = this.contract.methods.createCountry("NL", 100, 100, 100000000, this.account).encodeABI();
    const nonce = await this.web3.eth.getBlockTransactionCount(this.account);
    const rawTx = {
        nonce: this.utils.toHex(nonce), 
        gasLimit: this.utils.toHex(3000000),
        gasPrice: this.utils.toHex(this.utils.toWei('20', 'gwei')),
        data: encoded_tx,
        from: this.account,
        to: this.contractAddress
    };

    let tx = new Tx(rawTx);
    tx.sign(this.pvtKey);

    let serializedTx = tx.serialize();
    this.web3.eth.sendSignedTransaction('0x' + serializedTx.toString('hex'))
    .on('receipt', console.log);

The error is the following:

index.js:2178 Error: Returned error: {"id":6,"jsonrpc":"2.0","error":{"code":-32603}}
at Object.ErrorResponse (errors.js:29)

I have absolutely no idea where to look anymore and feel like I've tried everything, might it have anything to do with the fact that I'm connected to metamask? When I try to send this transaction through metamask with eth.method.send() the transaction does not give an error and behaves as expected.

Answer 1

To get the nonce you have to call web3.eth.getTransactionCount, and not getBlockTransactionCount.

• getTransactionCount

  Get the numbers of transactions sent from this address.

• getBlockTransactionCount

  Returns the number of transaction in a given block.

To debug interactions with ganache you can start with ganache-cli --verbose it will show the interactions between the client an ganache and show more details about transactions.