I am trying the delete and set_simple functions to rename a parameter's name, get a wrong answer.
so I take time to checked some code, the problem is in https://github.com/Kong/lua-multipart/blob/master/src/multipart.lua#L274-L301.

And I create a sister PR #23

------WebKitFormBoundaryEnMb9LHcspOC97yv
Content-Disposition: form-data; name="address"

Idpetfectone
------WebKitFormBoundaryEnMb9LHcspOC97yv--

multipart/mixed
multipart/related
multipart/form-data
multipart/alternative

I got all the properties, but how to determine which one is a file?

multipart_data:set_simple is useful, but I need a new method to upload file with header like:

--------------------------bd99c856fd831904
Content-Disposition: form-data; name="record"; filename="run_test.sh"
Content-Type: application/octet-stream

../../bin/lua run_test.lua $@

--------------------------bd99c856fd831904--

Any suggestions?

------WebKitFormBoundaryEnMb9LHcspOC97yv
Content-Disposition: form-data; name="address"

Idpetfectone
------WebKitFormBoundaryEnMb9LHcspOC97yv--

"------WebKitFormBoundaryOK7yAUgUbAlqyGG8
Content-Disposition: form-data; name="file"; filename="test.bin"
Content-Type: application/octet-stream

test!!!
------WebKitFormBoundaryOK7yAUgUbAlqyGG8--
"
How to get "test!!!"
Thanks.

I am adding one parameter in request body if POST request (Content-Type= "multipart-form/data") but after adding when i set edited body in kong request, file format changed from csv to string. Any suggestion?

Code:
local Multipart = require("multipart")
local multipart_data = Multipart(kong.request.get_raw_body(), kong.request.get_header("Content-Type"))
multipart_data["vendor"]="{ "vendorId" : "vicky", "vendorName" : "vicky" }"
kong.service.request.set_body(multipart_data)

Request Body:

Please see first comment here: Kong/kong#2851.

Suggestion: A method to return the value directly instead of :get(xxx).value

I'd be willing to submit a PR if this is liked.

Just wondering why have you decided to do the parse manually instead of use this library https://github.com/openresty/lua-resty-upload?

This is just my first approach of using part of your logic + lua-resty-upload but I think it could be even cleaner https://gist.github.com/zot24/03e97fe48e74c4cb84a9

What do you think?

in function MultipartData.new(data, content_type), the boundary is searched by using the expression ";%s+boundary=(%S+)".

This works correctly for e.g. this Content-Type header:

Content-Type: multipart/form-data; boundary=AAAH...

But the whitespace after the semicolon is optional (and the pattern expects a whitespace). If the whitespace is not there, the field boundary is nil and parsing of the request will fail.

E.g. in when using Kong 0.8.3 with Oauth2 and a multipart upload, this fails as following:

share/lua/5.1/multipart.lua: in function 'decode'
share/lua/5.1/multipart.lua:112: in function 'Multipart'
share/lua/5.1/kong/plugins/oauth2/access.lua:93: in function 'retrieve_parameters'
share/lua/5.1/kong/plugins/oauth2/access.lua:359: in function 'parse_access_token'
share/lua/5.1/kong/plugins/oauth2/access.lua:412: in function 'execute'
share/lua/5.1/kong/plugins/oauth2/handler.lua:12: in function 'access'
share/lua/5.1/kong.lua:188: in function 'access'```

Solution: in multipart.lua:109 the value of boundary should also be found, if no whitespace is sent after the ; by the client in the value of the header Content-Type

I see this lib is capable of decoding files but not encode them.

some specific request may cause is_header() hang on regex match for a very long time under 100% cpu usage.
This could be easily reproduced
s = (' '):rep(100000)..('a'):rep(100000);string.match(s, "(%S+):%s*(%S+)")

Hi!
Could you tell about your tests result, please?
Do your recommend your code for production usage?

Nick	Message
daurn	@thibaultcha: I don't see why we couldn't have a multipart library with a streaming api that doesn't depend on any openresty specific apis.
daurn	@thibaultcha: did you read the irc transcript with furq?
daurn	(oh: and it should have both multipart encode and decode)
thibaultcha	@Daurn: I haven't read it, but I do agree that this should be totally feasable in an unopinonated streaming fashion
daurn	thinking about decoding api: multipart/formdata can be nested
daurn	I think there would be SAX-style 'pull' with events like "start of part" "part body chunk" "part body chunk" "end of part"
thibaultcha	only I wonder, such an API would not be able to append or remove fields on the fly... Or would it?
thibaultcha	Actually, it could, if the API handles it pre- encoding/decoding...
daurn	@thibaultcha: there should be a streaming decoder and a streaming encoder. if you wanted to append/edit/remove then you'd have something in the middle there as a filter
thibaultcha	yeah
thibaultcha	that'd be nice
daurn	@thibaultcha: how would you feel about doing this under the 'lua-multipart' project? as a new major version
daurn	only thing is that I'd like to have the lua-http 'headers' object available
thibaultcha	Any reason you see for wanting to stick under the lua-multipart project though? Just curious
thibaultcha	Otherwise it'd be fine as a major version yeah
daurn	@thibaultcha: well it's a nice succinct name ;)
thibaultcha	Indeed

Per https://tools.ietf.org/html/rfc2046#section-5.1.1 it is permissible and often necessary to enclose boundary strings in quotes, i.e. both the following are valid

Content-Type: multipart/form-data; boundary=6VDnJMUegpEalEvpihpZUgF0JbjBVVgDXb0aZQcw
Content-Type: multipart/form-data; boundary="6VDnJMUegpEalEvpihpZUgF0JbjBVVgDXb0aZQcw"

and should result in the boundary string 6VDnJMUegpEalEvpihpZUgF0JbjBVVgDXb0aZQcw.

Currently, lua-multipart extracts the boundary string using this:

instance._boundary = match(content_type, ";%s*boundary=(%S+)")

which will attempt to use quotes as part of the boundary. An HTTP request like this will not parse successfully, as there are no quotes present in boundary in the body:

POST /test HTTP/1.1
Host: example.com
Content-Type: multipart/form-data; boundary="6VDnJMUegpEalEvpihpZUgF0JbjBVVgDXb0aZQcw"

foo

--6VDnJMUegpEalEvpihpZUgF0JbjBVVgDXb0aZQcw
Content-Type: text/plain; charset="utf-8"
Content-disposition: form-data; name="api_key"

c63211ec-2157-4c35-8c38-2d9584bbee15
--6VDnJMUegpEalEvpihpZUgF0JbjBVVgDXb0aZQcw
Content-Type: text/plain; charset="utf-8"
Content-disposition: form-data; name="username"

popuko

I tried to decode the multipart encoded file and form data on my server
for the text format file , the lines with only \r\n are lost
for the binary format file , the file is damaged

Is this parser can only be used for multipart/form-data encoded form data ? what about file ?

Related to Kong/kong#565

example.txt
Hi!
My file example.txt is attached.

local Multipart = require("multipart")
local io = require("io")
local open = io.open
local function read_file(path)
    local file = open(path, "r")
    if not file then return nil end
    local content = file:read "*a"
    file:close()
    return content
end
local body = read_file("example.txt");
local multipart_data = Multipart(body, "text/html")
local t = multipart_data:tostring()
print (t)

This code prints empty line. What's wrong? Please, explain it.