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Both web3js and web3php are just libraries to communicate with the Ethereum blockchain.
You can ask through a browser (then you'd use web3js), or from a server (then you'd use web3php), some information (like, what's the balance of this address, or call some contract's method to read something).
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Generally call will default to using 0x0000000000000000000000000000000000000000 as msg.sender, which is why this is reverting. That address is indeed not owner, so a revert is what you would expect. You can do call though and specific the msg.sender by doing await exchange.methods.isAdmin().call({from:addressYouWantToUse}) and replace the placeholder with ...
1
First let me say that I don't know if you can do it with Web3 (easily), but my guess would be no.
Personally I would use The Graph. You can use it to listen to specific events, functions calls or blocks, see handlers here. Inside the mappings you can further filter for any transaction data to identify the transactions you are looking for.
The whole process ...
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The function changes execution according to signature passed
if (bytes(signatures[i]).length == 0) {
callData = data[i];
} else {
callData = abi.encodePacked(bytes4(keccak256(bytes(signatures[i]))), data[i]);
}
If it is empty it will assume the function call is contained in data[i]. You would have to use web3.eth.abi....
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