`bdk_electrum` v0.23.1 release bumped to API-incompatible dependencies on a patch release.

[tnull]

Describe the bug
The v0.23.1 release of bdk_electrum bumped the underlying minor version of rust-electrum-client on a patch release. This has the builds of previous releases of LDK Node fail due to the mismatching API types. E.g.:

error[E0599]: the method `populate_tx_cache` exists for struct `Arc<BdkElectrumClient<Client>>`, but its trait bounds were not satisfied
   --> src/chain/electrum.rs:487:23
    |
487 |         bdk_electrum_client.populate_tx_cache(cached_txs);
    |                             ^^^^^^^^^^^^^^^^^ method cannot be called on `Arc<BdkElectrumClient<Client>>` due to unsatisfied trait bounds
    |
   ::: /home/tnull/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/electrum-client-0.23.1/src/client.rs:32:1
    |
32  | pub struct Client {
    | ----------------- doesn't satisfy `_: ElectrumApi` or `electrum_client::Client: Deref`
    |
    = note: the following trait bounds were not satisfied:
            `electrum_client::Client: Deref`
            which is required by `electrum_client::Client: bdk_electrum::electrum_client::ElectrumApi`

error[E0599]: the method `full_scan` exists for struct `Arc<BdkElectrumClient<Client>>`, but its trait bounds were not satisfied
   --> src/chain/electrum.rs:490:24
    |
490 |             bdk_electrum_client.full_scan(
    |             --------------------^^^^^^^^^ method cannot be called on `Arc<BdkElectrumClient<Client>>` due to unsatisfied trait bounds
    |
   ::: /home/tnull/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/electrum-client-0.23.1/src/client.rs:32:1
    |
32  | pub struct Client {
    | ----------------- doesn't satisfy `_: ElectrumApi` or `electrum_client::Client: Deref`
    |
    = note: the following trait bounds were not satisfied:
            `electrum_client::Client: Deref`
            which is required by `electrum_client::Client: bdk_electrum::electrum_client::ElectrumApi`

error[E0599]: the method `populate_tx_cache` exists for struct `Arc<BdkElectrumClient<Client>>`, but its trait bounds were not satisfied
   --> src/chain/electrum.rs:521:23
    |
521 |         bdk_electrum_client.populate_tx_cache(cached_txs);
    |                             ^^^^^^^^^^^^^^^^^ method cannot be called on `Arc<BdkElectrumClient<Client>>` due to unsatisfied trait bounds
    |
   ::: /home/tnull/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/electrum-client-0.23.1/src/client.rs:32:1
    |
32  | pub struct Client {
    | ----------------- doesn't satisfy `_: ElectrumApi` or `electrum_client::Client: Deref`
    |
    = note: the following trait bounds were not satisfied:
            `electrum_client::Client: Deref`
            which is required by `electrum_client::Client: bdk_electrum::electrum_client::ElectrumApi`

error[E0599]: the method `sync` exists for struct `Arc<BdkElectrumClient<Client>>`, but its trait bounds were not satisfied
   --> src/chain/electrum.rs:524:24
    |
524 |             bdk_electrum_client.sync(request, BDK_ELECTRUM_CLIENT_BATCH_SIZE, true)
    |                                 ^^^^ method cannot be called on `Arc<BdkElectrumClient<Client>>` due to unsatisfied trait bounds
    |
   ::: /home/tnull/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/electrum-client-0.23.1/src/client.rs:32:1
    |
32  | pub struct Client {
    | ----------------- doesn't satisfy `_: ElectrumApi` or `electrum_client::Client: Deref`
    |
    = note: the following trait bounds were not satisfied:
            `electrum_client::Client: Deref`
            which is required by `electrum_client::Client: bdk_electrum::electrum_client::ElectrumApi`

To Reproduce
Try to build LDK Node.

Expected behavior
Should build.

Please don't arbitrarily bump dependencies as part of patch releases. To fix this, we'll now first have to upgrade electrsd, and then have to push out a new LDK Node release that work around the API breakage.

[oleonardolima]

Oh, apologies for that! I've totally missed the SemVer for this one. I think we could do:

• Yank the v0.23.1 and release bdk_electrum v0.24.0 instead;
• Yank the current v0.23.1 and release another one without the electrum-client bump;

Would that help ? Let's see what others think.

[tnull]

Oh, apologies for that! I've totally missed the SemVer for this one. I think we could do:

• Yank the v0.23.1 and release bdk_electrum v0.24.0 instead;
• Yank the current v0.23.1 and release another one without the electrum-client bump;

Would that help ? Let's see what others think.

I don't know. I now went ahead and opened RCasatta/electrsd#104 / lightningdevkit/ldk-node#602 / lightningdevkit/ldk-node#603 / lightningdevkit/rust-lightning#3991

We intended to ship an LDK Node patch release with a hotfix for the rustls::CryptoProvider issue in the coming days anyways, so we might now just go ahead with it (as soon as electrsd ships a new release with above bump PR included we're unblocked to do so). So maybe it would be easiest to leave as-is now, but would be appreciated if this could be avoided in the future.

[oleonardolima]

I don't know. I now went ahead and opened RCasatta/electrsd#104 / lightningdevkit/ldk-node#602 / lightningdevkit/ldk-node#603 / lightningdevkit/rust-lightning#3991

We intended to ship an LDK Node patch release with a hotfix for the rustls::CryptoProvider issue in the coming days anyways, so we might now just go ahead with it (as soon as electrsd ships a new release with above bump PR included we're unblocked to do so). So maybe it would be easiest to leave as-is now, but would be appreciated if this could be avoided in the future.

Alright, got it. Yes, the CryptoProvider fix is only in the latest v0.24.0. Additionally, a newly released electrsd version would unblock other work to migrate to corepc-node and corepc-client here as well.

Sure, sorry again for the inconvenience.