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node.jshttppostmultipartform-datarestler

Using node and restler for multipart form-data POST


I am able to upload a file using restler.file in the data section with no problem. I am now trying to write a very short CSV data string, which I am not able to find documentation for the data function, but reading the code I thought I had it correct:

restler.post("http://posttestserver.com/post.php", {
    multipart: true,
    data: {
            "upload": restler.data("people.csv", "text/csv", '384;213;Status Update'),
            "returnURL": ""
    }
}).on("complete", function(data) {
     console.log(data);
});

Unfortunately this just hangs and will time out. I tried adding EOF and other things to the 3rd arg but I know I am missing something. The data string I have above is the exact same contents as the file that works when I use restler.file. I would rather not have to write out a CSV file if I don't have to before POSTing it.


Solution

  • EDIT ----

    As per @Joni's comment to the question above, this problem seems to have been rectified after a fix was submitted via pull request.

    Original Answer (from OP) ----

    From the research on restler (and corresponding with the maintainer) it doesn't look like restler can do what I wanted. Note: Someone has committed some code that would allow a file part in the form of a stream, but it hasn't been accepted into the branch and I don't have enough experience with streams.

    I solved the problem going back to basics. I read the RFC for multipart (http://www.ietf.org/rfc/rfc2388.txt) and found there are only a few rules to be aware of in constructing the body, mostly some extra \r\n's and '--' in the right places.

    I decided to simply format the raw POST body and send it through the basic node http client.

    This worked:

    var http = require('http');
    
    postBody = new Buffer(
        '------WebKitFormBoundaryebFz3Q3NHxk7g4qY' + "\r\n" +
        'Content-Disposition: form-data; name="upload"; filename="filename.csv"' + "\r\n" +
        'Content-Type: text/csv' + "\r\n" +
        '\r\n' +
        'comma,separated,values' + "\r\n" +
        '------WebKitFormBoundaryebFz3Q3NHxk7g4qY' + "\r\n" +
        'Content-Disposition: form-data; name="returnUrl"' + "\r\n" + 
        '\r\n' +
        'http://return.url/' + "\r\n" +
        '------WebKitFormBoundaryebFz3Q3NHxk7g4qY--'
        );
    
    var headers = {
      "Content-Type": "multipart/form-data; boundary=----WebKitFormBoundaryebFz3Q3NHxk7g4qY",
      "Content-Length": postBody.length
    };
    
    //These are the post options
    var options = {
      hostname: 'myhost.com',
      port: 80,
      path: '/myPost',
      method: 'POST',
      headers: headers
    };
    
    // so we can see that things look right
    console.log("postBody:\n" + postBody);
    console.log("postBody.length:\n" + postBody.length);
    
    var responseBody = '';
    
    // set up the request and the callbacks to handle the response data
    var request = http.request(options, function(response) {
        // when we receive data, store it in a string
        response.on('data', function (chunk) {
            responseBody += chunk;
        });
        // at end the response, run a function to do something with the response data
        response.on('end',function() {
            console.log(responseBody);
        });
    });
    
    // basic error function
    request.on('error', function(e) {
      console.log('problem with request: ' + e.message);
    });
    
    // write our post body to the request
    request.write(postBody);
    // end the request
    request.end();
    

    I hope this helps people doing multipart/form-data.