'request formData to API, gets “Network Error” in axios while uploading image

I am making a POST request to server to upload an image and sending formdata using axios in react-native. i am getting "Network Error". i also try fetch but nothing work.using react native image picker libeary for select image.in postman api working fine

        formData.append('title', Title);
        formData.append('class_id', selectClass._id)
        formData.append('subject_id', checkSelected)
        formData.append('teacher_id', userId)
        formData.append('description', lecture);
        formData.append('type', 'image');

       var arr=[];
       arr.push(imageSource)
       arr.map((file,index)=>{
       formData.append('file',{
       uri:file.path,
       type:file.type,
       name:file.name
       })
       })


       axios({
       method: 'post',
       url: URL + 'admin/assignment/create',
       data: data,
       headers: {
       "content-type": "multipart/form-data",
       'x-auth-token': token,
        },
       })
     .then(function (response) {
    //handle success
    console.log('axios assigment post',response);
      })
   .catch(function (response) {
     //handle error
      console.log('axios assigment post',response);
    });


Solution 1:[1]

"react-native": "0.62.1", "react": "16.11.0", "axios": "^0.19.2",

weird solution i have to delete debug folder in android ->app->source->debug

and restart the app again its solve my problem. i think it's cache problem.

Solution 2:[2]

Project keeps flipper java file under app > source > debug in react native > 0.62. There is an issue with Flipper Network that causes the problem in your case. If you remove the debug folder, you will not be able to debug Android with Flipper, so the best solution is upgrading Flipper version in android > gradle.properties to 0.46.0 that fixes the problem.

You can change it with this line FLIPPER_VERSION=0.46.0

Solution 3:[3]

I faced the same issue. The following steps worked for me.

  1. update FLIPPER_VERSION=0.52.0 latest
  2. for formData code as below:
let formData = new FormData();
let file = {
          uri: brand.uri, 
          type: 'multipart/form-data', 
          name: brand.uri
};
formdata.append('logo', file);

The type must be 'multipart/form-data' as the post header.

Solution 4:[4]

REACT NATIVE SOLUTION

If you are using Axios or Fetch in React Native and you got Network Error when uploading the file or data.

Try to commenting below line from the /android/app/src/main/java/com/{your_project}/MainApplication.java

its located around the 40-50 line

initializeFlipper(this, getReactNativeHost().getReactInstanceManager())

https://github.com/facebook/react-native/issues/28551

Solution 5:[5]

The issue that I was facing which is close to what you are mentioning is that I was getting NetworkError when using image-picker and trying to upload the file using axios. It was working perfectly in iOS but not working in android.

This is how I solved the issue.

There are two independent issues at action here. Let’s say we get imageUri from image-picker, then we would use these following lines of code to upload from the frontend.

const formData = new FormData();
formData.append('image', {
 uri : imageUri,
 type: "image",
 name: imageUri.split("/").pop()
});

The first issue is with the imageUri itself. If let’s say photo path is /user/.../path/to/file.jpg. Then file picker in android would give imageUri value as file:/user/.../path/to/file.jpg whereas file picker in iOS would give imageUri value as file:///user/.../path/to/file.jpg.

The solution for the first issue is to use file:// instead of file: in the formData in android.

The second issue is that we are not using proper mime-type. It is working fine on iOS but not on Android. What makes this worse is that the file-picker package gives the type of the file as “image” and it does not give proper mime-type.

The solution is to use proper mime-type in the formData in the field type. Ex: mime-type for .jpg file would be image/jpeg and for .png file would be image/png. We do not have to do this manually. Instead, you can use a very famous npm package called mime.

The final working solution is:

import mime from "mime";

const newImageUri =  "file:///" + imageUri.split("file:/").join("");

const formData = new FormData();
formData.append('image', {
 uri : newImageUri,
 type: mime.getType(newImageUri),
 name: newImageUri.split("/").pop()
});

I hope this helps to solve your problem :)

Solution 6:[6]

I had this problem and solve it via commenting the 43 line in android/src/debug/.../.../ReactNativeFlipper.java

// builder.addNetworkInterceptor(new FlipperOkhttpInterceptor(networkFlipperPlugin));

could you test it?

Solution 7:[7]

change this line: form_data.append('file', data);

To form_data.append('file', JSON.stringify(data));

from https://github.com/react-native-image-picker/react-native-image-picker/issues/798

You need to add this uesCleartextTraffic="true" to the AndroidManifest.xml file found inside the dir android/app/src/main/AndroidManifest.xml

<application ... android:usesCleartextTraffic="true"> Then, Because of issue with Flipper Network.

I commented initializeFlipper(this, getReactNativeHost().getReactInstanceManager())

in this file /android/app/src/main/java/com/{your_project}/MainApplication.java

Also, commenting out line number 43 in this file android/app/src/debug/java/com/**/ReactNativeFlipper.java

line43: builder.addNetworkInterceptor(new FlipperOkhttpInterceptor(networkFlipperPlugin));

Solution 8:[8]

If using expo and expo-image-picker, then the problem is only with the image type and nothing else.

In the latest updates, they removed the bug related to path (as other answers mention to change the beginning of the path which was correct for the older versions).

Now to remove the problem, we need to change the type only and is mentioned by other answers to use mime which works fine;

 import mime from 'mime'


const data = new FormData();
data.append('image', {
     uri: image.uri,
     name: image.uri.split('/').pop() // getting the text after the last slash which is the name of the image
    type: mime.getType(image.uri) // image.type returns 'image' but mime.getType(image.uri) returns 'image/jpeg' or whatever is the type

})

Solution 9:[9]

In my case, after debbuging for a while, the issue was in nginx.
The image was "too big".

I Had to add annotations to the Kubernetes ingress:

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  annotations:
    nginx.ingress.kubernetes.io/proxy-body-size: 20m
....

It was a bit tricky to debug since the request never got through the load balancer (nginx) to the Api service. The "Network error" message didn't help a lot either.

Solution 10:[10]

I am using Expo SDK 42 (react-native v0.63). And I was using the expo-document-picker library to pick the documents & upload to server.

This is the code I am using to open the picker & get the metadata about the file.

const result = await DocumentPicker.getDocumentAsync({
    type: 'image/*',
    copyToCacheDirectory: false,
    multiple: false,
});

if (result.type === 'success') {
    const name_split = result.name.split('.');
    const ext = name_split[name_split.length - 1];
    // result.uri = 'file://' + result.uri;
    result.type = helper.get_mime_type(ext);
    delete result.size;
}

(You can write your function to get the mime type from the file extension or use some library from npm)

And this is the code I am using to upload the file to server:

const formdata = new FormData();
formdata.append('custom_param', 'value');
formdata.append('file', result); // 'result' is from previous code snippet

const headers = {
    accept: 'application/json',
    'content-type': 'multipart/form-data',
};

const opts = {
    method: 'POST',
    url: 'your backend endpoint',
    headers: headers,
    data: formdata,
};
return await axios.request(axiosopts);

The above code is the working code. I want to explain what I did wrong initially that was causing the Network Error in axios.

I had set copyToCacheDirectory to true initially and the uri I was getting in the result was in the format /data/path/to/file.jpeg. And I also tried appending file:// to beginning of the uri but it didn't work.

I then set copyToCacheDirectory to false and the uri I was getting in the result was in the format content://path/to/file.jpeg. And this didn't cause any Network Error in axios.

Solution 11:[11]

I have faced this error as well. I found out that I got this error because the file path is wrong and axios couldn't find the file. It is a weird error message when the uri is wrong though but that's what actually has happened. So double checking the uri of the file would fix the issue. Mainly consider file://.