Ethereum: How to Extract Input Address and Amount from VIN
When working with Ethereum transactions, understanding the VIN (unique identification number) is critical for accurate data extraction. In this article, we will take an in-depth look at how to extract the input address and amount from a given VIN.
VIN Structure
A VIN consists of several components:
txid: The transaction ID
vout: The output index
n: The number of inputs (optional)
i: The index of an input (optional)
In your example, the VIN is:
"vin": [
{
"txid": "e3f0e88ce224d342a0189c1b9d2fd488d8bda2f303dbe1e1dbbaa5f51d9f4a53",
"vout": 1,
"n": 1, // No inputs
"i": 0 // Input index (optional)
}
]
Extracting the input address and amount
To extract the input address and amount, amount of a VIN, you can use the vin object properties. Here’s how to do it:
function vinToData(vin) {
const inputIndex = vin.vout; // Get the output index (Input Index)
const txid = vin.txid;
const amount = vin.i ? vin[i + 1].amount : null; // Get the first Amount if i is not -1
return {
txid,
vout: inputIndex, // Remove the index from the VIN
amount,
inputs: vin.inputs.map((input) => ({
txid: input.txid,
amount: input.amount,
n: input.n,
i: input.i,
}))
};
}
This function assumes that the vin object has an i property for the Amount, and if it does not, it returns null. The vout of the VIN is used to obtain the Input Index.
Example of use
Let’s say you have a transaction with the following VIN:
"vin": [
{
"txid": "e3f0e88ce224d342a0189c1b9d2fd488d8bda2f303dbe1e1dbbaa5f51d9f4a53",
"vout": 1,
...
You can use the vinToData function to extract the input address and amount:
const vin = {
txid: "e3f0e88ce224d342a0189c1b9d2fd488d8bda2f303dbe1e1dbbaa5f51d9f4a53",
vout: 1,
i: 0
};
const data = vinToData(vin);
console.log(data); // Output: { txid, vout, amount, inputs }
In this example, the output will be an object with the following properties:
txid: The transaction ID
vout: The input index (1)
amount: The amount associated with the input
inputs: An array of objects containing:
+ txid: The transaction ID of the input
+ amount: The amount of the input
+ n: The number of inputs
+ i: The index of the input (if not -1)
This is a basic example and you may need to modify the code to suit your specific use case. Also, keep in mind that this information is typically only available if the transaction was mined on the Ethereum mainnet or the EIP-1559 network.