imageupload.js

import { RNS3 } from 'react-native-aws3';

// ....

  stringGen(len){
    // for generating random strings obviously
    let text = "";
    let charset = "abcdefghijklmnopqrstuvwxyz0123456789";
    for( var i=0; i < len; i++ )
        text += charset.charAt(Math.floor(Math.random() * charset.length));
    return text;
  }

  addPhoto(){
    let that = this;
    let options = {
      keyPrefix: "imgs/",
      bucket: "secretbucketname",
      region: "us-east-1",
      accessKey: "AK----------------",
      secretKey: "2X----------------------------------",
      successActionStatus: 201
    };

    let randString1 = (this.stringGen(23)) + ".jpg";
    let somePhoto = {
        uri:  this.state.photoLocation,
        name: randString1,
        type: this.state.photoType
    };

    RNS3.put(somePhoto, options).then(response => {
      if (response.status !== 201){
        alert("some error occured");
      }else{
        that.setState({
          photoLiveLocation: response.body.postResponse.location,
        })
      }
    }).catch(function(error){
      alert(error.message);
    })
  }