How can I check confirmations number for some bitcoin address programmatically? (I have eCommerce shop where each order has separate address). I want to use blockchain.info API.
Here is an example of the API call, but I can't figure out what numbers should I check in API response:
https://blockchain.info/rawaddr/1JbBiCzQqzE2dW9TCzA6w7N27jVDXxwreD
Confirmations for an address aren't really a thing. Addresses are not confirmed; transactions are. A single address is typically used in multiple transactions: one where the address is used as an output, and one where the first transaction was used as an input. Although it's not a best practice, addresses can even be re-used multiple times.
It looks like this particular address has been used in two different transactions. Once as an output in 00c83c7677d414053488d0b51067feee157a5b82d5acec5bfe8e9c540c11c624, and once as in input in 378f829160cb9c99cc7a8fb1152472b80f0e1ea9c9cc24118dbccc2da72dedcf.
Each of these two transactions returned in the API response has a block_height value (489353 and 489355). That is the block at which the transaction was included. To find how many confirmations each transaction has, subtract the block_height by the height of the most recently confirmed block, and add 1. So if the current block is 489355, one transaction has 1 confirmation, and the other has 3.
If you are using php, then try this :
function response ($result) {
header("Content-Type:application/json");
$response['confirmation'] = $result;
$json_response = json_encode($response);
echo $json_response;
}
$tx_hash = '5e910a5b61e3ccdb7...'; // try to get a new tx hash from blockchain.info/.com
$bcinfo = json_decode(file_get_contents("https://blockchain.info/rawtx/".$tx_hash), true);
$latest = json_decode(file_get_contents("https://blockchain.info/latestblock"), true);
if(isset($bcinfo['block_height'])) {
$block_height = $bcinfo['block_height'];
$height = $latest['height'];
response($height - $block_height + 1);
}else{
response(0); // not yet has any confirmations
}
