location/listlocation.html at master · web3examples/location · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
<!DOCTYPE html>
<html>
    <head>
        <meta name="viewport" content="width=device-width, initial-scale=1, user-scalable=no" />
        <meta charset="UTF-8">
        <script src="https://unpkg.com/web3@latest/dist/web3.min.js"></script>
    </head>

    <body>
        <h1>List of checkins to locations relative to HHS</h1>
        <pre id="log" style="width:100%;height:200px"></pre>

 <script type="text/javascript">
    function log(str,...arguments) {
            var logstr=arguments.toString();
            document.getElementById("log").innerHTML +=str+" "+logstr+"\n";
        }

var url = new URL(window.location.href);
var matchaddress = url.searchParams.get("address");
if (matchaddress) log(`Only showing address: ${matchaddress}`);

const web3 = new Web3( Web3.givenProvider );

function sleep(ms) {
  return new Promise(resolve => setTimeout(resolve, ms));
}

async function processevent(object)
{
     var ts='';
     var decoded=web3.eth.abi.decodeParameters(['uint256'], object.data);
     var txHash=object.transactionHash;
     const trx = await web3.eth.getTransaction(txHash);
     var from = trx.from;
     if (matchaddress && matchaddress.toLowerCase() != from.toLowerCase())
            return; // only show requested address

     for (i = 0; i < 5; i++) {
        blockobject= await web3.eth.getBlock(object.blockNumber);
        if (!blockobject) {
            await sleep(1000);
        }
     }
     if (blockobject)
        ts = new Date(blockobject.timestamp * 1000).toString(); // javascript uses milliseconds
     var dist=decoded['0'];
     log(`${from},${ts},${dist}`);
}

log('From (address), From (name), Date-time, Distance (meters)');

async function f() {
    address="0x609F224c0c9405a1e7FD404114ca8A8606edC3a3";
    var subscription= web3.eth.subscribe('logs', {fromBlock: '0x0',address: address} )
    .on("data", processevent )
    .on("changed", console.log)
    .on("error",console.log)
}

f();

        </script>
    </body>
</html>