I need to make a multipart/form-data request
Which should look like these:
Content-Disposition: form-data; name='file'
Content-Type: application/pdf
Content-Transfer-Encoding: base64
...Base64Content...
I know how I could transform a file into base64 but how can I add the Content-Type and the Content-Transfer-Encoding to a multipart/form-data field?
Thanks for your help!
I think you can work around this using the Base 64 dynamic value:
Set the body in Multipart mode, and add a new field name
In the value field, right click and pick Encoding > Base 64 > Encode
In that base 64 dynamic value's input field, right click and pick File > File Content
Pick the file you want to encode
Though, it's currently impossible to set custom headers in the attachment, so you won't be able to set the Content-Type and Content-Transfer-Encoding, unfortunately.
Here's an example: https://paw.pt/aPPHzLRh (hit "Open in Paw")
Related
I try on server side to distinguish between the upload of empty file and not-uploaded file
The POST body content of an empty file is:
------WebKitFormBoundaryAYxCGhPMYcmdkdlv
Content-Disposition: form-data; name="_1"
dd
------WebKitFormBoundaryAYxCGhPMYcmdkdlv
Content-Disposition: form-data; name="_2"; filename="foo"
Content-Type: application/octet-stream
------WebKitFormBoundaryAYxCGhPMYcmdkdlv
Content-Disposition: form-data; name="_3"
Upload
------WebKitFormBoundaryAYxCGhPMYcmdkdlv--
While missing file is
------WebKitFormBoundaryMldAHhbBqWpKPlRY
Content-Disposition: form-data; name="_1"
dd
------WebKitFormBoundaryMldAHhbBqWpKPlRY
Content-Disposition: form-data; name="_2"; filename=""
Content-Type: application/octet-stream
------WebKitFormBoundaryMldAHhbBqWpKPlRY
Content-Disposition: form-data; name="_3"
Upload
------WebKitFormBoundaryMldAHhbBqWpKPlRY--
The only difference is filename= content one is empty other contains the file name (same behavior for Firefox and Chromium)
Questions:
Are there any conditions that browser wouldn't provide a filename (security or something like that)?
Is it actually valid/standard way to distinguish between empty file and non-set file, please provide reference.
Is Content-Type: application/octet-stream is standard response and it will be set in case of non-uploaded file?
I'd like to see some references to standards that confirm or disprove my observations
1. Filename
The original specification for "Form-based File Upload in HTML" was RFC1867
According to that specification, the filename parameter
"is not required, but is strongly recommended in any case where the original filename is known"
This spec was superceded by RFC2388 - "Returning Values from Forms: multipart/form-data", which states
The sending application MAY supply a file name ... as specified in RFC2184;
(where RFC2184 goes on to stress its importance, without requiring it)
Note that it refers to "the sending application". The spec makes it clear that it is application agnostic.
For a cross-browser view on actual implementation however, Mozilla's MDN documentation for FormData sheds some light on it.
In the context of FormData.append() where a file/blob is set but filename is not set explicitly:
The default filename for Blob objects is "blob". The default filename for File objects is the file's filename.
2. Difference between empty & no file
To answer this, it's important to note Section 5.7 of RFC2388 - "Correlating form data with the original form"
This specification provides no specific mechanism by which
multipart/form-data can be associated with the form that caused it to
be transmitted. This separation is intentional...
This is answered in the HTML5 specification however, which details how form data is constructed.
...if the field element is an <input> element whose type attribute is in the File Upload state, then for each file selected in the <input> element, append an entry to the form data set with the name as the name, the file (consisting of the name, the type, and the body) as the value, and type as the type. If there are no selected files, then append an entry to the form data set with the name as the name, the empty string as the value, and application/octet-stream as the type.
This matches your observation above.
Looking to how a real-world server implementation deals with this, take the PHP runtime as an example.
Its API makes no distinction between "no file" and "empty file" - and will raise a single error UPLOAD_ERR_NO_FILE in either case.
As PHP is open source (written in C), you can see that implementation here
3. MIME content-type encoding
This is answered in #2 above - As detailed in the HTML5 spec, (from a compliant browser) it will always be application/octet-stream where the form value is empty.
For completeness, if a file is provided, RFC2388 specifies that:
If the contents of a file are returned via filling out a form, then the file input is identified as the appropriate media type, if known, or "application/octet-stream"
I'm trying to understand the http request, when I send a string of data using the post method on the request body there is a value that we send as below:
--------------------------d74496d66958873e
Content-Disposition: form-data; name="person"
anonymous
--------------------------d74496d66958873e
but if we send a file using post method it will be like this:
--------------------------d74496d66958873e
Content-Disposition: form-data; name="fileToUpload"; filename="icon.png"
Content-Type: image/png
-O9†q#ë#ÞÿËà3l†v}uá#t(<‡c3f
úS©59ñõCáa#Ž¡#Za%ð.ž zxý˜F#ZqÄð&^
jx[1…ÕЊËÂ$Æ‚#Þ
--------------------------d74496d66958873e
my question is:
what is the foreign character contained between -------------------------- d74496d66958873e when we send the file?
i mean
-O9†q#ë#ÞÿËà3l†v}uá#t(<‡c3f
úS©59ñõCáa#Ž¡#Za%ð.ž zxý˜F#ZqÄð&^
jx[1…ÕЊËÂ$Æ‚#Þ
whether the character is a binary, hexa, or base64 or what?
how to change image file to the character when we want to write http request manually using programming language?
Those are plain binary bytes. All the bytes that the file icon.png contained when it was sent by the HTTP client.
The format is described in RFC 1867 and basically works like this:
--[boundary]
[headers]
[N bytes]
--[boundary]
[headers]
[M bytes]
--[boundary]--
To extract the contents, you'll need to parse past the boundary, parse the headers (0, 1 or many) and then read the binary data until you reach the ending boundary. (The final boundary has two extra dashes on the right.)
... and there can be any amount of such parts, in a single multipart POST.
The encoding of content is told by the header field "ContentType". But how do I know the encoding of this header field?
I mean the characters "ContentType" is encoded in UTF8 or sth else?
Header field values are essentially US-ASCII, unless the definition of the header field says something else (right now, node does).
One way to encode non-ASCII characters is to use an overlay encoding such the one defined in RFC 5987 (but the header field definition still needs to opt into that).
I'm using Jmeter version 2.9, HTTP sampler to test my rest services.
The GET and POST are working without any issues, where as PUT is not passing any parameters in the request to the server.
I verified it with view results in tree.
Any reasons on why this is happening and work around this issue?
It worked for me. Based on what I read on internet, there were different solutions suggested:
Changing Content-Encoding to UTF-8
Pass the PUT parameters in the "body data" tab (as opposed to passing them in tabular format in the "Parameters" tab)
Setting Content-Type header to application/json in the HTTP Header Manager
Passing the parameters via a file (even if this were to work, how would you pass dynamic values?)
passing it as POST with a combination of above points.
WHAT WORKED FOR ME is this combination: Set content type to application/json + Pass parameters as "JSON" in the **body data tab (below is an example)
I did not need to specify UTF-8 or anything else.
EXAMPLE JSON PARAMETER BODY:
{"title":"JMeterTitle","preMortar":"JMeterPre","postMortar":"JMeterPost"}
Pass parameters in path field using:
?name=value&name2=value2
and body in Raw Post body.
if it doesn't work report a bug .
Example:
I am using JMeter 2.11 and I had the same problem. I solved in this way:
1) Setting Content-Type header similar to that you are using in your api method(Example: application/json or application/x-www-form-urlencoded etc.) in the HTTP Header Manager.
2)In HTTP Request. Body Data should look like this:
KEY=VALUE&KEY=VLAUE&KEY=VLAUE&KEY=VLAUE.......
First, try see the logs.
Had a similar problem.
I was using wrongly the "Content-enconding" field as it were the HTTP
Content-Type param. They are not related.
If you need to set Content-Type=application/json you have to use a "HTTP Header Manager" config element.
After setting correctly Content-enconding to UTF-8 the put request started to work.
You should add a parameter with an empty name (in the "parameters" tab).
If the problem persists use the result tree view to analyze the request settings.
I'm using JMeter 2.13 and facing with similar problem. This is How I've solved it:
Setting Content-Type header to text/plain in the HTTP Header Manager
Changing Content-Encoding to UTF-8
In the parameters tab, add the params without name and separated with ampersand character (&)
Screenshot JMeter PUT request example
Hope it helps!
what is the default encoding one should use to decode multipart/form-data if no charset is given? RFC2388 states:
4.5 Charset of text in form data
Each part of a multipart/form-data is supposed to have a content-
type. In the case where a field element is text, the charset
parameter for the text indicates the character encoding used.
For example, a form with a text field in which a user typed 'Joe owes
<eu>100' where <eu> is the Euro symbol might have form data returned
as:
--AaB03x
content-disposition: form-data; name="field1"
content-type: text/plain;charset=windows-1250
content-transfer-encoding: quoted-printable>>
Joe owes =80100.
--AaB03x
In my case, the charset isn't set and I don't know how to decode the data within that text/plain section. As I do not want to enforce something that isn't standard behavior I'm asking what the expected behavior in this case is. The RFC does not seem to explain this so I'm kinda lost.
Thank you!
This apparently has changed in HTML5 (see http://dev.w3.org/html5/spec-preview/constraints.html#multipart-form-data).
The parts of the generated multipart/form-data resource that correspond to non-file fields must not have a Content-Type header specified.
So where is the character set specified? As far as I can tell from the encoding algorithm, the only place is within a form data set entry named _charset_.
If your form does not have a hidden input named _charset_, what happens? I've tested this in Chrome 28, sending a form encoded in UTF-8 and one in ISO-8859-1 and inspecting the sent headers and payload, and I don't see charset given anywhere (even though the text encoding definitely changes). If I include an empty _charset_ field in the form, Chrome populates that with the correct charset type. I guess any server-side code must look for that _charset_ field to figure it out?
I ran into this problem while writing a Chrome extension that uses XMLHttpRequest.send of a FormData object, which always gets encoded in UTF-8 no matter what the source document encoding is.
Let the request entity body be the result of running the multipart/form-data encoding algorithm with data as form data set and with utf-8 as the explicit character encoding.
Let mime type be the concatenation of "multipart/form-data;", a U+0020 SPACE character, "boundary=", and the multipart/form-data boundary string generated by the multipart/form-data encoding algorithm.
As I found earlier, charset=utf-8 is not specified anywhere in the POST request, unless you include an empty _charset_ field in the form, which in this case will automatically get populated with "utf-8".
This is my understanding of the state of things. I welcome any corrections to my assumptions!
The default charset for HTTP 1.1 is ISO-8859-1 (Latin1), I would guess that this also applies here.
3.7.1 Canonicalization and Text Defaults
--snip--
The "charset" parameter is used with some media types to define the character set (section 3.4) of the data. When no explicit charset parameter is provided by the sender, media subtypes of the "text" type are defined to have a default charset value of "ISO-8859-1" when received via HTTP. Data in character sets other than "ISO-8859-1" or its subsets MUST be labeled with an appropriate charset value. See section 3.4.1 for compatibility problems.
Thanks to the detailed explanation by #owlman.
Just some more info here:
Upload request payload fragment:
------WebKitFormBoundarydZAwJIasnBbGaUqM
Content-Disposition: form-data; name="file"; filename="xxx.txt"
Content-Type: text/plain
If "xxx.txt" has some UNICODE char in it using UTF-8 encoding, Resin(as of 4.0.40) can't decode it correctly, but Jetty(9.x) can.
I think the reason for Resin's behavior is that the Content-type doesn't specify any encoding, so Resin decode file name using "ISO8859-1", which may result in garbled characters.
I did some googling:
https://mail-archives.apache.org/mod_mbox/struts-user/200310.mbox/%3C3FA0395B.1080209#kumachan.net.nz%3E
It seems that Resin's behavior is according to Servlet Spec 2.3
And I can't find any settings from http://www.caucho.com/resin-4.0/reference.xtp
which can change this behavior for Resin.