Cache rpc results

[kumavis]

i've been working on some alternate web3 providers that let a user run a dapp without setting up and running a node. We've noticed some dapps trigger very aggressive polling for state. Since our network requests can take a little longer to resolve, we've seen significant improvements by caching network results. The setup looks like this:

• web3 continuously polls for the latest block
• while the block remains the same we can cache any results regarding the state of accounts (balance, storage)
• when the block increments, we dump the cache

we're implementing this at the provider level, but seems like something that everyone could benefit from at the web3 level

thoughts? would you merge a PR based on this?

[tcoulter]

👍 Would love to see this behavior implemented in web3. Due to provider idiosyncrasies, would love the polling interval be configurable.

[frozeman]

What about a chain re-org where the latest block changes?
We are actually thinking about introducing push events, so that we can get rid of this polling all together.

This would make the cache obsolete right away, so i would rather wait..

[kumavis]

What about a chain re-org where the latest block changes?

re-org invalidates cache, seems pretty straightforward

This would make the cache absolute right away,

not sure what you mean

EDIT: absolute -> obsolete, ok I get it.

We are actually thinking about introducing push events

is there a gh issue for this or something to follow?

[frozeman]

ethereum/go-ethereum#1867

Which is only one part and a proposal, but we are discussing a pushing API

EDIT, its actually only about internal events. For the real new push API exists no issue for now.

[kumavis]

what do you think of http long polling for blocks?

[frozeman]

Would require changes on both node and web3. We are already going another route (push).

[kumavis]

@frozeman what protocol are you going to push over?

[fjl]

@kumavis Bit late to the discussion but the answer we settled on is WebSocket. geth 1.4.x has WebSocket support and there are RPC methods for subscribing to push events on the connection. Push events are sent as JSON-RPC notifications.

[kumavis]

@fjl thanks

[kumavis]

@frozeman @fjl hey gents, is there an update on the websocket work? looking for an issue to follow.

[frozeman]

Those are the relevant threads:

• ERC: Pub/Sub + web sockets in web3.js ethereum/EIPs#51
• ethereumProvider API ethereum/interfaces#16