Feature: query for spending transaction input txid+index

[antonilol]

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this would allow home node runners running mempool and electrs to click the red arrows on the right to go to the spending transactions of that specific tx output

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a way to query the already indexed spending data

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blockstream/electrs - way too heavy for my home node
stopping electrs to read the db - not feasible to constantly stop and start, and having to make something to read the db
making my own spending tx indexer - it would cost additional storage and time

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#777

btw: i am willing to contribute to this, i just have to find some free time to learn Rust

[romanz]

Could you please try #454?

It can be tested using:

$ echo '{"jsonrpc": "2.0", "method": "blockchain.outpoint.subscribe", "params": ["d2684048acb9e03041a4fbb9621d09dd854af5c07545c32fa724b2a06eb969d5", 1], "id": 0}' | netcat 127.0.0.1 50001
{"id":0,"jsonrpc":"2.0","result":{"height":760861,"spender_height":0,"spender_txhash":"f37332e4a895182742f9d722c01927fb1142fd28c680ef8c13a6d18bf6f6b34d"}}

$ echo '{"jsonrpc": "2.0", "method": "blockchain.outpoint.subscribe", "params": ["b6c2962349a45ca661f1004fc077e3eb2b093e7baebdbce081c2f23b1605dfa8", 0], "id": 0}' | netcat 127.0.0.1 50001
{"id":0,"jsonrpc":"2.0","result":{"height":761571,"spender_height":761576,"spender_txhash":"2f5a8119c16a5b1262b784d2715e9b91c4c480b00bff87281e71b74f16c3d469"}}

$ echo '{"jsonrpc": "2.0", "method": "blockchain.outpoint.subscribe", "params": ["b6c2962349a45ca661f1004fc077e3eb2b093e7baebdbce081c2f23b1605dfa8", 1], "id": 0}' | netcat 127.0.0.1 50001
{"id":0,"jsonrpc":"2.0","result":{"height":761571,"spender_height":761573,"spender_txhash":"8eaba51c919990713debb33d0d45807274aa023d668c48c0c3733a9d6033c0a0"}}

$ echo '{"jsonrpc": "2.0", "method": "blockchain.outpoint.subscribe", "params": ["a435a4c3c3ec511967fc81b109c35c336c75900d930187040dcab8149366f996", 0], "id": 0}' | netcat 127.0.0.1 50001
{"id":0,"jsonrpc":"2.0","result":{"height":761576}}

[antonilol]

That works! thanks, i get the right txid, but could there be an easier way to just get the data, instead of having to subscribe, check if spending data is returned and then unsubscribe?

would it be possible to also return the input index?