I'm using axios in my app. When I make a post request for the very first time after opening the app, it is failing with the following error. From second time onwards, it works without any issue.
Network Error
- node_modules/axios/lib/core/createError.js:15:17 in createError
- node_modules/axios/lib/adapters/xhr.js:81:22 in handleError
- node_modules/event-target-shim/dist/event-target-shim.js:818:20 in EventTarget.prototype.dispatchEvent
- node_modules/react-native/Libraries/Network/XMLHttpRequest.js:600:10 in setReadyState
- node_modules/react-native/Libraries/Network/XMLHttpRequest.js:395:6 in __didCompleteResponse
- node_modules/react-native/Libraries/vendor/emitter/EventEmitter.js:189:10 in emit
- node_modules/react-native/Libraries/BatchedBridge/MessageQueue.js:416:4 in __callFunction
- node_modules/react-native/Libraries/BatchedBridge/MessageQueue.js:109:6 in __guard$argument_0
- node_modules/react-native/Libraries/BatchedBridge/MessageQueue.js:364:10 in __guard
- node_modules/react-native/Libraries/BatchedBridge/MessageQueue.js:108:4 in callFunctionReturnFlushedQueue
* [native code]:null in callFunctionReturnFlushedQueue
I'm running on a real android device connecting to a real server by http://my_ip:my_port/. Same post request I tried by creating a Native android project in kotlin, and it is working without any issue
Here is my code:
const upload = () => {
setAnalyzing(true);
axios.post(URL_PREDICT, formBody(), {
headers: {
'Content-Type': 'multipart/form-data'
}
}).then(handleSuccess)
.catch(handleFail);
}
const formBody = () => {
const photo = {
uri: image,
type: 'image/jpeg',
name: 'photo.jpg',
};
const form = new FormData();
form.append("file", photo);
return form;
};
const handleFail = (error) => {
console.log(error)
console.log(error?.response?.data);
setAnalyzing(false);
toggle();
alert("ERROR " + error);
};
const handleSuccess = response => {
console.log('success...');
setAnalyzing(false);
toggle();
console.log(response);
navigation.navigate('Result', response);
};
Any idea whats causing this?
I think you are using expo-image-picker
.
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 the 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()
});