Update text inside text file? - google-api

Question

I can't find in create and update methods of Google Drive API, where should I put actual text that I want to be inside my text file. Where is this parameter?
With this query I only create empty file:
await window.gapi.client.drive.files.create({
resource: {
'name': `${knowledgeFile.id}.txt`,
'parents': [`${srcDataFolderId}`]
},
media: {
mimeType: 'text/plain',
body: convertHTMLToPlainText(knowledgeFileHTML)
},
fields: 'id'
})

Answer 1

After creating a text file on your drive, you can update its content with the Files: update request
To do so
Specify the new content as a string
Transform the content string into a byte array
Get the existing file by its id
Read the file as binary string with FileReader
Create a new file metadara as a bytearray merging the old and the new contents
Perform an Files:Update request specifying the new file metadata as request body
Sample
function updateFile() {
var fileId = "YOUR FILE ID";
var contentString = "Hello world";
var contentArray = new Array(contentString.length);
for (var i = 0; i < contentArray.length; i++) {
contentArray[i] = contentString.charCodeAt(i);
}
var byteArray = new Uint8Array(contentArray);
var newData = new Blob([byteArray], {
type: 'text/plain'
});
var request = gapi.client.drive.files.get({
'fileId': fileId
});
request.execute(function(oldData) {
var boundary = '-------314159265358979323846';
var delimiter = "\r\n--" + boundary + "\r\n";
var close_delim = "\r\n--" + boundary + "--";
var reader = new FileReader();
reader.readAsBinaryString(newData);
reader.onload = function(e) {
var contentType = newData.type || 'application/octet-stream';
var base64Data = btoa(reader.result);
var multipartRequestBody =
delimiter + 'Content-Type: application/json\r\n\r\n' + JSON.stringify(oldData) + delimiter + 'Content-Type: ' + contentType + '\r\n' + 'Content-Transfer-Encoding: base64\r\n' + '\r\n' + base64Data + close_delim;
var request = gapi.client.request({
'path': '/upload/drive/v2/files/' + fileId,
'method': 'PUT',
'params': {
'uploadType': 'multipart',
'alt': 'json'
},
'headers': {
'Content-Type': 'multipart/mixed; boundary="' + boundary + '"'
},
'body': multipartRequestBody
});
request.execute();
}
});
}