Failed to convert data to 'utf8' encoded string

[radreamer]

Hi, i get next error when trying to readStream asset from CameraRoll:

Failed to convert data to 'utf8' encoded string, this might due to the source data is not able to convert using this encoding. source = *** -[__NSPlaceholderDictionary initWithObjects:forKeys:count:]: attempt to insert nil object from objects[1]

Environment

Environment: OS: macOS High Sierra 10.13.3 Node: 9.5.0 Yarn: Not Found npm: 5.6.0 Watchman: 4.9.0 Xcode: Xcode 9.2 Build version 9C40b Android Studio: 3.0 AI-171.4443003

Packages: (wanted => installed) react: ^16.2.0 => 16.2.0 react-native: ^0.53.0 => 0.53.0 react-native-fetch-blob: ^0.10.8 => 0.10.8

Sample code

RNFetchBlob.fs
      .readStream(
        upload.uri, // link to CameraRoll asset (begins with assets-library://)
        'utf8',
        4000000,
        100
      )
      .then(ifstream => {
        ifstream.open()
        ifstream.onData(chunk => {
          from = to
          to = from + chunk.length
          uploadChunked(resp.data.upload_key, chunk, from, to, upload.size)
        })
        ifstream.onError(err => {
          console.log('oops', err)
        })
        ifstream.onEnd(() => {
          uploadFinalize(resp.data.upload_key)
        })
      })

'base64' and 'ascii' works fine, but they are useless for my case

[radreamer]

The problem, that i tried to solve was MULTIPART uploading of large files, which fail my application with the next error: NSMallocException: Application threw exception NSMallocException: Failed to grow buffer In this case the RAM was constantly growing up (in Perf Monitor widget).

I spend on this much time and finally find a solution:

const Blob = RNFetchBlob.polyfill.Blob
    Blob.build(RNFetchBlob.wrap(upload.uri)).then(file => {
      const CHUNK_SIZE = 4000000
      let readBytes = 0
      let totalUploaded = 0
      let uploaded = 0
      let from = 0
      let to = 0

      const uploadNextChunk = uploaded => {
        totalUploaded += uploaded

        if (upload.size === totalUploaded) {
          // finalize upload here and close file
          file.close()
        } else {
          const chunk = Math.min(upload.size - readBytes, CHUNK_SIZE)
          const blob = file.slice(readBytes, readBytes + chunk)

          readBytes += chunk

          from = to
          to = from + chunk

          const xhr = new RNFetchBlob.polyfill.XMLHttpRequest()
          xhr.open('POST', `${upload_url}`)

          xhr.setRequestHeader('Content-Range', `bytes ${from}-${to - 1}/${upload.size}`)

          xhr.onload = () => {
            uploadNextChunk(to - from)
          }

          xhr.send(blob)
        }
      }
      uploadNextChunk(uploaded)
    })

After this i measured RAM again and found that it was not constantly growing up anymore, instead it grew to some value and reset after it.

Hope, that this snippet will help someone

[JulioOrellana]

Hello, thanks for your snippet. I have a problem that upload stops before first chunk, can you help me guess why? does your snippet works fine for your uploads?

[radreamer]

@JulioOrellana hi! yes, it works well for me, what kind of error do you get? maybe your server expects other headers