Support idxdb on node.js

[WiktorStarczewski]

No description provided.

[igamigo]

Is this mostly in relation to #1437? If so, would you mind outlining the changes that are required for this to work? Mainly looking to understand tradeoffs and see if we have any options (for instance, use a different store implementation for Node)

[WiktorStarczewski]

Is this mostly in relation to #1437? If so, would you mind outlining the changes that are required for this to work? Mainly looking to understand tradeoffs and see if we have any options (for instance, use a different store implementation for Node)

Yeah it is. I started working on this and got to a decent point but got distracted.
There are two main things for the Node support:

• IndexedDB
  • Solved by using a idxdb shim for node which implements sqlite under the hood, and does it transparently (no calling code has to be adjusted) - this seems to work well with this PR
• gRPC
  • This can't be solved otherwise than on infra side, since we cant do native gRPC (HTTP/2) in node, we want to do HTTP/1.1 gRPC-Web, but that doesnt work because the current infra setup employs a redirect converting such requests to gRPC, but only in web context. So my current idea is to provide a version of the node that always redirects (testnet-web or similar), I enquired already with gateway what effort that would be and it would be low, so I think that will constitute the bulk of my proposal.

So its almost there but needs some polish (hence the draft).
Happy to hear your thoughts on the approach though.

[igamigo]

I see, so basically what we briefly discussed in the issue.

• IndexedDB
  • Solved by using a idxdb shim for node which implements sqlite under the hood, and does it transparently (no calling code has to be adjusted) - this seems to work well with this PR

This is cool if it works well enough, but we already currently logically separate store implementations through the Store trait, so I wonder if we could provide a different implementation that is native (ie, that does not require the IndexedDB shim). In this sense, we should be able to provide a way of instantiating a WebClient with a native SQL store (that would not be available in browser contexts) or the browser-compatible IndexedDB store. I think this might require some changes to the WebAuthenticator and how it relates to the WebClient (see this)

• gRPC
  • This can't be solved otherwise than on infra side, since we cant do native gRPC (HTTP/2) in node, we want to do HTTP/1.1 gRPC-Web, but that doesnt work because the current infra setup employs a redirect converting such requests to gRPC, but only in web context. So my current idea is to provide a version of the node that always redirects (testnet-web or similar), I enquired already with gateway what effort that would be and it would be low, so I think that will constitute the bulk of my proposal.

What stops using native gRPC in node environments? After a quick search there do seem to be a few libraries that do this, but it's possible I'm missing something. In this case too I think we already mostly have the right abstraction (the NodeRpcClient trait), so I wonder if we could just create an RPC client crate/mod that forwards calls to @grpc/grpc-js and then we ship a node entrypoint that uses this instead of the current tonic-web-wasm-client-based RpcClient (that goes through the browser's fetch()(