Upload file to rails 6 api backend from react-native using axios

Question

i want to upload image with data to my rails 6 api using axios. I try with formdata but I am getting an ActiveSupport::MessageVerifier::InvalidSignature error. Here is my code:

uploadToServer= () => {
    const file =this.state.photo

    let formdata = new FormData()
    formdata.append('name', this.state.name)
    formdata.append('photo', file)


   axios.post(
         'api',
         formdata,
         {
           headers: {
             'Content-type' : 'multipart/form-data',
             'Authorization':'xx'
           }
         }
       ).then(resp => console.log(resp)).catch(error => console.error(error)); 

}

This is the error I receive:

Completed 500 Internal Server Error in 171ms (ActiveRecord: 46.0ms | Allocations: 32866)



ActiveSupport::MessageVerifier::InvalidSignature (ActiveSupport::MessageVerifier::InvalidSignature):

Any help is very much appreciated. Thanks in advance

Answer 1

I had the same problem in reactjs. I think your photo file should be a " blob " file. I solved it like that

import Resizer from 'react-image-file-resizer';

imageInputHandler = (event) =>{
    var fileInput = false
    if(event.target.files[0]) {
        fileInput = true
    }
    if(fileInput) {
        Resizer.imageFileResizer(
            event.target.files[0],
            800,
            800,
            'JPEG',
            100,
            0,
            uri => {
                console.log("ok....resized")
                this.setState({
                  file: uri
                })
            },
            'blob',
            200,
            200,
        );
    }   
  }

And then sent the parameter to the Rails API with fetch() like that

 const formData = new FormData();
  formData.append('text', self.state.text);
  formData.append('user_id', self.props.user_id);
  formData.append('image', self.state.image);
  fetch('http://localhost:3000/posts/create', {
    method: 'POST',
    body: formData
  })

But of course not in the same event handler because the state won't be updated yet, and it worked. For some reason, I couldn't do it neither using axios.

And don't forget to permit the params in your Rails controller

  def create
    @post=Post.create(post_params)
    image_url=rails_blob_path(@post.image , only_path: true) if @post.image.attached?
    render json: {text: @post.text, image: image_url, user_id: @post.user_id, id:@post.id }
  end
  
  private
  def post_params
      params.permit( :text, :user_id, :image )
  end