extract text from image and show it in html page - node.js

Question

i have a problem : i made a function to extract text from image with ocr space api in backend when i called it with postTypeRequest(...) in angular it worked
i added a declaration text: string and i gave it the extracted text from backend to call it in html tag and show results in my project but it shows this problem : Type 'Object' is not assignable to type 'string'
the console shows an empty data like this :
[1]: https://i.stack.imgur.com/PmRDn.png
ress is empty and its type is object
so i think ress should return string not object
home.component.ts
onSubmit() {
console.log('image', this.image);
const formData = new FormData();
formData.append('file', this.image ,'file');
return this.api.postTypeRequest('/api/scan/images', formData).subscribe((res) => {
console.log(res) ;
this.text =res //add a variable to call it in html {{text}} and show results
} )
}
scan.controller.js
const uploadImage = (req,res)=> {
let imageDetails = {
name: req.file.originalname,
};
Scan.find({ name: imageDetails.name }, (err, callback) => {
if (err) {
res.json({
err: err,
message: `There was a problem creating the image because: ${err.message}`,
});
} else {
let attempt = {
name: req.file.originalname,
imageUrl: req.file.path,
imageId: "",
};
cloudinary.uploads(attempt.imageUrl).then((result) => {
let imageDetails = {
name: req.file.originalname,
imageUrl: result.url,
imageId: result.id,
};
Scan
.create(imageDetails)
.then((image) => {
imageFilePath =imageDetails.imageUrl
const rlt = ScanService.createScan(imageFilePath).then( ()=>{
res.json({
success: true,
data: image,
ress : rlt
});
})
})
.catch((error) => {
res.json({
success: false,
message: `Error creating image in the database: ${error.message}`,
});
});
});
}
});
}
scan.service.js
const createScan = async (imageFilePath) => {
ocrSpaceApi.parseImageFromUrl(imageFilePath, options)
.then(function (parsedResult) {
console.log('parsedText: \n', parsedResult.parsedText);
console.log('ocrParsedResult: \n', parsedResult.ocrParsedResult);
return parsedResult.parsedText,parsedResult.ocrParsedResult
}).catch(function (err) {
console.log('ERROR:', err);
})}```

Answer 1

The error is ocorring because you have an Object on the JSON response, so you need to check before assign the String value to your text.
In this case i yould recomendo you using a type check to make sure you are receiving your data as you expect.
Something on the lines of
if(typeof res !== "string") {
this.text = "";
return;
}
this.text = res;