@fluent-wallet/detect-provider

A tiny utility for detecting the Fluent Conflux/Ethereum provider, or any provider injected at window.conflux and window.ethereum.

It has 0 dependencies and works out of the box in any modern browser, for synchronously and asynchronously injected providers.

Usage

Keep in mind that the providers detected by this package may or may not support the Ethereum JavaScript Provider API. Please consult the Conflux Provider Doc and the Ethereum Provider Doc to learn how to use our provider.

Node.js

Conflux Provider

import detectProvider from '@fluent-wallet/detect-provider'

const provider = await detectProvider({
        injectFlag: "conflux",
        defaultWalletFlag: "isFluent",
})

if (provider) {

  console.log('Conflux successfully detected!')

  // From now on, this should always be true:
  // provider === window.conflux

  // Access the decentralized web!

  // Legacy providers may only have ethereum.sendAsync
  const chainId = await provider.request({
    method: 'cfx_chainId'
  })
} else {
  // if the provider is not detected, detectProvider will reject an error
  console.error('Please install Fluent Wallet!')
}

Ethereum Provider

import detectProvider from '@fluent-wallet/detect-provider'

const provider = await detectProvider({
        injectFlag: "ethereum",
        defaultWalletFlag: "isMetaMask",
})

if (provider) {

  console.log('Ethereum successfully detected!')

  // From now on, this should always be true:
  // provider === window.ethereum

  // Access the decentralized web!

  // Legacy providers may only have ethereum.sendAsync
  const chainId = await provider.request({
    method: 'eth_chainId'
  })
} else {

  // if the provider is not detected, detectProvider will reject an error
  console.error('Please install MetaMask!')
}

HTML

<script src="https://unpkg.com/@fluent-wallet/detect-provider/dist/detect-provider.min.js"></script>
<script type="text/javascript">
  const provider = await detectProvider({
        injectFlag: "conflux",
        defaultWalletFlag: "isFluent",
  }

  if (provider) {
    // handle provider
  } else {
    // handle no provider
  }
</script>

Options

The exported function takes an optional options object. If invalid options are provided, an error will be thrown. All options have default values.

options.silent

Type: boolean

Default: false

Whether error messages should be logged to the console. Does not affect errors thrown due to invalid options.

options.timeout

Type: number

Default: 3000

How many milliseconds to wait for asynchronously injected providers.

Advanced Topics

Overwriting or Modifying window.ethereum or window.conflux

The detected provider object returned by this package will strictly equal (===) window.ethereum or window.conflux for the entire page lifecycle, unless window.ethereum or window.conflux is overwritten. In general, consumers should never overwrite window.ethereum or window.conflux or attempt to modify the provider object.

If, as a dapp developer, you notice that the provider returned by this package does not strictly equal window.ethereum or window.conflux, something is wrong. This may happen, for example, if the user has multiple wallets installed. After confirming that your code and dependencies are not modifying or overwriting window.ethereum or window.conflux, you should ask the user to ensure that they only have a single provider-injecting wallet enabled at any one time.