I'm creating an API which should return data in a CSV format. I set the content-type header to text/csv but this forces a download of the contents as a csv file.
I'm using NodeJS and the express framework. It could be that this is standard behaviour. However I would like to know how you guys solved this issue.
This is a sample of the code that I'm using:
res.set('Content-Type', 'text/csv');
var toCsv = require('to-csv');
// obj is a just a standard JavaScript object.
res.send(toCsv(obj));
I would like that the person using the API can retrieve data in a CSV format without actually downloading a file
Maybe have a look at this question:
How does browser determine whether to download or show
It's your browser that decides that content of the type "text/csv" should be downloaded.
You should simply consider using another content-type, if you just want the csv to show in the browser as plain text.
Try this instead:
res.set('Content-Type', 'text/plain');
Related
I am trying to send to my flask app json data and having it return a CSV file. My ajax request is sending JSON data to the view via POST request and then the view is supposed to return back a csv file. However, it fails to return the csv file in the browser as a download. I'm not sure how to make it work or if its even possible. Thanks!
// AJAX - Send data over to python and return csv
$("#export").click(
function(){
$.ajax({
url: "/dbCSV",
type: "POST",
contentType: 'application/json;charset=UTF-8',
dataType:"json",
data: JSON.stringify(datam)
});
event.preventDefault();
}
);
#analyzers.route("/dbCSV", methods=["GET","POST"])
def dbCSV():
if request.method=="POST":
data = pd.DataFrame(request.get_json())
resp = make_response(data.to_csv())
resp.headers["Content-Disposition"] = "attachment; filename=export.csv"
resp.headers["Content-Type"] = "text/csv"
return resp
return jsonify({"msg":"Could not generate CSV File"})
I'd recommend using send_file(...) with a BytesIO (file stream) object:
from io import BytesIO
from flask import send_file
...
response_stream = BytesIO(data.to_csv().encode())
return send_file(
response_stream,
mimetype="text/csv",
attachment_filename="export.csv",
)
Keep in mind that you will not be able to open the download prompt when sending a POST request using AJAX. Instead, you will simply receive the file as an AJAX response. To solve this issue, you will have to take a look at this question:
download file using an ajax request
Maybe your code was already working and this was your problem – I can not tell from looking at it.
I finally figure it out. Basically I can store the user input using the session object available from the flask library. This allows different functions to access this rather then having to worry about creating global variables or passing them around via functions or objects.
Note 1- If the amount of user data that has to be saved is extensive then using Redis or some other type of in memory data storage would be a better choice in this case.
Save the csv file in static path and then use the that static path csv URL to get csv file in download form from browser.
I'm working with an API for uploading a user image, the uploading process is quite simple, just choose the file from the user's device and send it as it is in a FormData (File, Binary).
But, when it comes for downloading this file from the storage, the response is really wired for me and containing some characters that because of it I can't indicate if that is a problem from the back-end handling or it's an invalid file or it's a regular formula that I didn't deal with it before.
my question is what should this data represent? And how to convert it to a file that a user can download?
here is a screenshot of it.
here
After struggling with many cases, the problem was that I didn't define the content-type within the request headers
headers: {
'Content-Type': 'blob'
}
notice that this type of data is a regular Blob file.
for downloading it, review this question JavaScript blob filename
without link
for converting it to a base64 string, review this question Convert blob to base64
I am new to WSO2. I wrote Custom Java Class Mediator to transform JSON request to CSV format. I have a proxy service to SFTP the generated CSV file to a (MoveIT) folder.
Custom Mediator converts the JSON request properly to CSV format. But, when send the CSV file using transport.vfs.replyfilename to the endpoint, I see the 'text' wrapper as below in the CSV file:
{"text":"1,F20175_A.CSV,20200623135039\n2,123456789,2017-MO-BX-0048,123456789,987654321,Y/N,C/A,20190101,20201231,20190930,75000,44475.86,15563.52,0.00,15563.52,0.00,60039.38,14960.62,60039.38,0.00,20191218\n3,1,999999999\n"}
I set contentType, MessageType properties "text/plain". I also used vfs.ContentType to set to text/plain as below:
text/plain
I know I am missing something. Has anybody come across this issue in WSO EI 6.6? Should I go ahead and write Custom Message Formatter? Any tips?
I want the output to be written as:
1,F20169_A.CSV,20200617153638
2,123456789,2017-MO-BX-0048,123456789,987654321,Y/N,C/A,20190101,20201231,20190930,75000,44475.86,15563.52,0.00,15563.52,0.00,60039.38,14960.62,60039.38,0.00,20191218
3,1,999999999
Thanks!
It seems that after converting to the CSV format the result is available within a text tag. Therefore using the file connector [1] when you write to the file access the text content using //text() XPath. Please refer to the following sample configuration of inputContent.
<fileconnector.create>
<filePath>{$ctx:filePath}</filePath>
<inputContent>{//text()}</inputContent>
<encoding>{$ctx:encoding}</encoding>
<setTimeout>{$ctx:setTimeout}</setTimeout>
<setPassiveMode>{$ctx:setPassiveMode}</setPassiveMode>
<setSoTimeout>{$ctx:setSoTimeout}</setSoTimeout>
<setUserDirIsRoot>{$ctx:setUserDirIsRoot}</setUserDirIsRoot>
<setStrictHostKeyChecking>{$ctx:setStrictHostKeyChecking}</setStrictHostKeyChecking>
</fileconnector.create>
[1]-https://docs.wso2.com/display/ESBCONNECTORS/Working+with+the+File+Connector#WorkingwiththeFileConnector-create
I have a url similar to https://www.nonexistentsite.com/fubar.json where fubar.json is a public json file which will download to your file system if you navigate to the url with your browser. I have a React web app where I want to read that file directly so as to display some of its data. I don't want to bother with any kind of a backend that would download the file to the apps file system so that it can read it. I want the React front end to read it directly in it's client side code with a fetch or an axios call or something like that. I'm familiar with the typical situation where I have a REST url like https://www.nonexistentsite.com/fubar which I can call and get the data. I'm failing to find info on how to handle this situation.
You could use Axios to load the data from the json file.
Example usage;
axios.get('https://www.nonexistentsite.com/fubar.json')
.then(jsoncontent => {
console.log(jsoncontent);
//do stuff with jsoncontent here
});
Maybe I'm misunderstanding your question, but I believe if you are just needing to fetch the json from a hosted file, you should be able to do so with axios.get(url)
I am using the angularJS frontend framework and nodejs/express as a backend server to send and receive JSON. The backend sent a large JSON object to the frontend and I was wondering if I could download the JSON object from the frontend in CSV format.
The data is stored as json in an scope variable: $scope.data in an angular controller. Then I converted the data to a string in CSV format in the variable $scope.CSVdata. How do I get the CSVdata to download from the client browser?
I know nodejs can be set up to send a file in CSV format but it would be nice to keep the backend a clean JSON api.
Referencing this post I've thrown together quick demonstration on how this may be done using AngularJS:
JavaScript Demo (Plunker)
I've wrapped the referenced Base64 code in a service, and use it in the following way:
$scope.downloadCSV = function() {
var data = Base64.encode($scope.CSVData);
window.location.href = "data:text/csv;base64," + data;
};
There are some disadvantages to this method however as mentioned in the comments. I've pulled out some bullet points from the Wikipedia page on this subject. Head over there for the full list.
Data URIs are not separately cached from their containing documents (e.g. CSS or HTML files), therefore the encoded data is downloaded
every time the containing documents are re-downloaded.
Internet Explorer 8 limits data URIs to a maximum length of 32 KB. (Internet Explorer 9 does not have this limitation)
In IE 8 and 9, data URIs can only be used for images, but not for navigation or JavaScript generated file downloads.[7]
Base64-encoded data URIs are 1/3 times larger in size than their binary equivalent. (However, this overhead is reduced to 2–3% if the
HTTP server compresses the response using gzip)
Data URIs do not carry a filename as a normal linked file would. When saving, a default filename for the specified MIME type is
generally used.
[ . . . ]