Lua binding to libcurl
This module include three layer
-
lcurlmodule provide low level pure C binding to libcurl.
Almost ready and needs tests. I have no plans to change this API. -
cURLmodule provide compatibility for Lua-cURLv2 API.
Almost ready and needs tests. -
cURLmodule provide new high level API.
In fact for now it providelcurlAPI directly and needed to redesign.
lcurl API
Lua-cURLv2 API
Lua-cURLv3 API
Original Lua-cURLv2 binding has several problems:
- it can not return error codes but just raise Lua errors (Fixed. use
cURL.safemodule) - it raise Lua error from callback that may result resource leak in libcurl (Fixed.)
- it does not provide building multipart/formdata explicitly (Fixed.)
- it has memory leak when send multipart/formdata (Fixed.)
- it does not save string for curl options that may result crush in libcurl (Fixed.)
- there no way to get result for operations in multi interface (e.g. if one of easy operation fail you can not get result code/error message) (Fixed. But it does not very handy interface.)
- you can not use your own callback function to perform operation with multi interface (Could not be fixed without changing API.)
- you can not pass your context to callback functions (Could not be fixed without changing API.)
Using LuaRocks:
luarocks install Lua-cURL
Install current master:
luarocks install Lua-cURL --server=https://luarocks.org/dev
List of incompatibility with original Lua-cURLv2
- objects are tables
- multi:perform() also returns ("done",code), ("error",error) and ("response",code) records
- writer callback does not recv string len (just string itself)
- on Lua > 5.2 errors are objects but not strings
-- HTTP Get
curl.easy{
url = 'http://httpbin.org/get',
httpheader = {
"X-Test-Header1: Header-Data1",
"X-Test-Header2: Header-Data2",
},
writefunction = io.stderr -- use io.stderr:write()
}
:perform()
:close()-- HTTP Post
curl.easy()
:setopt_url('http://posttestserver.com/post.php')
:setopt_writefunction(io.write)
:setopt_httppost(curl.form() -- Lua-cURL guarantee that form will be alive
:add_content("test_content", "some data", {
"MyHeader: SomeValue"
})
:add_buffer("test_file", "filename", "text data", "text/plain", {
"Description: my file description"
})
:add_file("test_file2", "BuildLog.htm", "application/octet-stream", {
"Description: my file description"
})
)
:perform()
:close()-- FTP Upload
local function get_bin_by(str,n)
local pos = 1 - n
return function()
pos = pos + n
return (str:sub(pos,pos+n-1))
end
end
curl.easy()
:setopt_url("ftp://moteus:[email protected]/test.dat")
:setopt_upload(true)
:setopt_readfunction(
get_bin_by(("0123456789"):rep(4), 9)
)
:perform()
:close()-- Multi FTP Upload
-- We get error E_LOGIN_DENIED for this operation
e1 = curl.easy{url = "ftp://moteus:[email protected]/test1.dat", upload = true}
:setopt_readfunction(
function(t) return table.remove(t) end, {"1111", "2222"}
)
e2 = curl.easy{url = "ftp://moteus:[email protected]/test2.dat", upload = true}
:setopt_readfunction(get_bin_by(("e"):rep(1000), 5))
m = curl.multi()
m:add_handle(e1)
m:add_handle(e2)
while m:perform() > 0 do m:wait() end
while true do
h, ok, err = m:info_read()
if h == 0 then break end
if h == e1 then
assert(ok == nil)
assert(err:name() == "LOGIN_DENIED")
assert(err:no() == curl.E_LOGIN_DENIED)
end
if h == e2 then
assert(ok == true)
end
end