ethers-super-provider
v0.1.3 ethereum ethers.js provider
Used by alt0.io to provide highly reliable and fast chain listening.
How it works
- You supply it with a list of regular providers
- It will frequently benchmark (with
getBlockNumber
) the providers supplied and rank them by response time. Providers lagging in blocks won't be used. - Depending on the selected mode, calls are either:
- spread in cycles between the fastest providers (default)
- sent to the fastest providers in parallel and the first response is returned (fastest)
- If any call fails or stalls, it is retried on another provider with an exponential backoff.
Installation
npm install ethers-super-provider
Example Usage
import { SuperProvider } from "ethers-super-provider"
import { ethers } from "ethers"
const rpcs = [
"https://api.mycryptoapi.com/eth",
"https://cloudflare-eth.com",
"https://eth-mainnet.public.blastapi.io",
"https://rpc.ankr.com/eth",
]
const provider = new SuperProvider(rpcs.map((url) => new ethers.providers.JsonRpcProvider(url)))
const blockNumber = await provider.getBlockNumber()
console.log(blockNumber)
API
new SuperProvider(providers: Provider[], chainId: number, options?: SuperProviderOptions)
providers
: Array of providers to usechainId
: Chain ID to use (default: 1 / eth mainnet)options
: Options for the super provider
options
mode
: Mode to use for calls. Eitherspread
orparallel
. Default:spread
maxRetries
: Maximum number of retries for a call. Default:3
benchmarkFrequency
: Interval between benchmarks. Default:200000
(~3 minutes)acceptableBlockLag
: Maximum number of blocks a provider can lag behind the fastest provider. Default:0
benchmarkRuns
: Number of runs for each benchmark. Default:2
stallTimeout
: Timeout for a call to be considered stalled. Default:4000
(4 seconds)maxParallel
: Maximum number of parallel calls. Default:3
Which mode to use?
if you are not doing very frequent calls and/or want the absolute fastest results, regardless of network use or cost, use
parallel
which will send the request to many providers in parallel and return the first available response.for all other uses (espsecially if you are doing a lot of requests at once) use
spread
(default) which is more efficient. Limit expensive API calls to a provider. This is also more respectful for public providers as it won't flood them with requests you won't use.
Caveats
- Currently doesn't support subscriptions & listening to events with
.on()
. PR welcome. - Doesn't have a concept of quorum and doesn't compare results.
- Lots of untested edge cases.
Credit
Inspiration taken from ethers's FallbackProvider, essential-eth's FallthroughProvider and Chainlist's auto RPC benchmarking.
Used by
Author
plz follow me on twitter I don't have many followers
npm i [email protected]
Homepage
github.com/vincelwt/super-pr...Metadata
- MIT
- Whatever
- @vincelwt
- released 11/23/2022