Function useFallback

Creates a middleware, that tries to execute a main logger and uses the first working fallback middleware, if it fails, using a 'next function'.

Example

import log, { AsyncLoggerMiddleware, useFallback } from "@egomobile/log"

const myFirstMiddleware: AsyncLoggerMiddleware = (type, args, done) => {
   try {
     // do your stuff here

     done()  // tell the iteration, that we are finished here
   } catch (error) {
     done(error)  // you can explicitly tell the iteration
                  // that some failed here and we need to execute
                  // the upcoming fallback
   }
}

// is only called, if 'myFirstMiddleware' fails
const mySecondMiddleware: AsyncLoggerMiddleware = (type, args, done) => {
  // do your stuff here
  //
  // if something fails here and throws an error
  // it is the same thing as calling 'done(error)'

  done()  // tell, that we are OK here
}

// is only called, if 'mySecondMiddleware' fails
const myThirdMiddleware: AsyncLoggerMiddleware = (type, args, done) => {
  // do your stuff here

  done()
}

log.use( useFallback(myFirstMiddleware, mySecondMiddleware, myThirdMiddleware) )

log('foo')
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