[Draft] Shield Funds from cached UTXOs #339
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remove unused imports rename index column of utxos table fix: move Script back to Vec<u8> Add missing imports [WIP] move code to chain.rs and catch up with latest changes reset wallet.rs fix SQL query
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I'm happy to pair with you to fix up any/all the issues so far! But I have a larger question, shouldn't the actual construction of the autoshielding transaction be done using the transaction builder in the zcash_client_backend trait? Right now you must be doing that outside of the rust code, right?
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| use crate::{error::SqliteClientError, BlockDB}; | ||
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| pub mod init; | ||
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| pub struct UnspentTransactionOutput { |
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This type should probably go in zcash-client-backend; we don't actually want any functions depending on any types or calling anything in zcash_client_sqlite directly; the only things that should be used from this crate (not through the DAA) are the WalletDB and BlockDB initialization functions.
| anchor_height: BlockHeight, | ||
| address: &str | ||
| ) -> Result<Vec<UnspentTransactionOutput>,SqliteClientError> { | ||
| let mut stmt_blocks = cache.0.prepare( |
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What is inserting data into this table?
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The rust welding on mobile wallets. The idea is that libruszcash only reads from this table as it only reads the compact_blocks table. Should I add the insertion code as well to make this 'self-sufficient' ? what's the compact_blocks approach?
| params: &P, | ||
| cache: &BlockDB, | ||
| anchor_height: BlockHeight, | ||
| address: &str |
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Can this address be wrapped in a better type? You could pass the Magna Carta here. :)
| . ok_or(format!( | ||
| "Could not interpret {} as a valid Zcash address.", | ||
| addr | ||
| )).unwrap(); |
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unwrap() should never be used, this error needs to be propagated out. Here's an example of something similar: https://github.com/zcash/librustzcash/blob/master/zcash_client_sqlite/src/wallet.rs#L79-L85
| txid: txid, | ||
| index: index, | ||
| script: script, | ||
| value: Amount::from_i64(value).unwrap(), |
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Same comment about unwrap() here, you don't want to crash the process.
| let mut utxos = Vec::<UnspentTransactionOutput>::new(); | ||
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| for utxo in rows { | ||
| utxos.push(utxo.unwrap()) |
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Same, no unwrap, this is a place to use collect()
Codecov Report
@@ Coverage Diff @@
## master #339 +/- ##
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Coverage 64.88% 64.88%
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Files 69 69
Lines 7066 7066
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Hits 4585 4585
Misses 2481 2481
Continue to review full report at Codecov.
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Subsumed by #341 |
The Idea of this PR is start to improve this PoC to the point it can be merged into the rust Crates.
Background: During the Holiday break I had the idea of putting together a Proof of Concept of how we could manage to shield funds from a t-address a light client using the data-access-api branch (now on master) and adding the needed functionality sot that:
given a set of UTXOs for a t-address obtained from lightwalletd, a light client could store them in a cache (BlockDb) and invoke a function in librustzcash that would take those funds and shield them to a z-address derived from a spending key. The user would have to use the Transparent Secret Key corresponding to those transparent outputs as proof of spendability
Librustzcash should be able to get all the UTXOs from the shared cache and build a shielding transaction