What should a Multipart HTTP request with multiple files look like?

HttpFileMultipart

Http Problem Overview


I'm working on an iPhone app that makes a multipart HTTP request with multiple image files.

It looks like what's happening, on the server side, is that one of the images is getting parsed properly, but the other two files are not.

Can anybody post a sample HTTP multipart request that contains multiple image files?

Http Solutions


Solution 1 - Http

Well, note that the request contains binary data, so I'm not posting the request as such - instead, I've converted every non-printable-ascii character into a dot (".").

POST /cgi-bin/qtest HTTP/1.1
Host: aram
User-Agent: Mozilla/5.0 Gecko/2009042316 Firefox/3.0.10
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-us,en;q=0.5
Accept-Encoding: gzip,deflate
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7
Keep-Alive: 300
Connection: keep-alive
Referer: http://aram/~martind/banner.htm
Content-Type: multipart/form-data; boundary=2a8ae6ad-f4ad-4d9a-a92c-6d217011fe0f
Content-Length: 514

--2a8ae6ad-f4ad-4d9a-a92c-6d217011fe0f
Content-Disposition: form-data; name="datafile1"; filename="r.gif"
Content-Type: image/gif

GIF87a.............,...........D..;
--2a8ae6ad-f4ad-4d9a-a92c-6d217011fe0f
Content-Disposition: form-data; name="datafile2"; filename="g.gif"
Content-Type: image/gif

GIF87a.............,...........D..;
--2a8ae6ad-f4ad-4d9a-a92c-6d217011fe0f
Content-Disposition: form-data; name="datafile3"; filename="b.gif"
Content-Type: image/gif

GIF87a.............,...........D..;
--2a8ae6ad-f4ad-4d9a-a92c-6d217011fe0f--

Note that every line (including the last one) is terminated by a \r\n sequence.

Solution 2 - Http

EDIT: I am maintaining a similar, but more in-depth answer at: https://stackoverflow.com/a/28380690/895245

To see exactly what is happening, use nc -l and an user agent like a browser or cURL.

Save the form to an .html file:

<form action="http://localhost:8000" method="post" enctype="multipart/form-data">
  <p><input type="text" name="text" value="text default">
  <p><input type="file" name="file1">
  <p><input type="file" name="file2">
  <p><button type="submit">Submit</button>
</form>

Create files to upload:

echo 'Content of a.txt.' > a.txt
echo '<!DOCTYPE html><title>Content of a.html.</title>' > a.html

Run:

nc -l localhost 8000

Open the HTML on your browser, select the files and click on submit and check the terminal.

nc prints the request received. Firefox sent:

POST / HTTP/1.1
Host: localhost:8000
User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux i686; rv:29.0) Gecko/20100101 Firefox/29.0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-US,en;q=0.5
Accept-Encoding: gzip, deflate
Cookie: __atuvc=34%7C7; permanent=0; _gitlab_session=226ad8a0be43681acf38c2fab9497240; __profilin=p%3Dt; request_method=GET
Connection: keep-alive
Content-Type: multipart/form-data; boundary=---------------------------9051914041544843365972754266
Content-Length: 554

-----------------------------9051914041544843365972754266
Content-Disposition: form-data; name="text"

text default
-----------------------------9051914041544843365972754266
Content-Disposition: form-data; name="file1"; filename="a.txt"
Content-Type: text/plain

Content of a.txt.

-----------------------------9051914041544843365972754266
Content-Disposition: form-data; name="file2"; filename="a.html"
Content-Type: text/html

<!DOCTYPE html><title>Content of a.html.</title>

-----------------------------9051914041544843365972754266--

Aternativelly, cURL should send the same POST request as your a browser form:

nc -l localhost 8000
curl -F "text=default" -F "[email protected]" -F "[email protected]" localhost:8000

You can do multiple tests with:

while true; do printf '' | nc -l localhost 8000; done

Attributions

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Content TypeOriginal AuthorOriginal Content on Stackoverflow
QuestionbpapaView Question on Stackoverflow
Solution 1 - HttpDaniel MartinView Answer on Stackoverflow
Solution 2 - HttpCiro Santilli Путлер Капут 六四事View Answer on Stackoverflow