Module std.net.curl
Networking client functionality as provided by libcurl. The libcurl library must be installed on the system in order to use this module.
Note
You may need to link with the curl library, e.g. by adding "libs": ["curl"]
to your dub.json file if you are using DUB.
Windows x86 note: A DMD compatible libcurl static library can be downloaded from the dlang.org download archive page.
This module is not available for iOS, tvOS or watchOS.
Compared to using libcurl directly, this module allows simpler client code for common uses, requires no unsafe operations, and integrates better with the rest of the language. Furthermore it provides range access to protocols supported by libcurl both synchronously and asynchronously.
A high level and a low level API are available. The high level API is built entirely on top of the low level one.
The high level API is for commonly used functionality such as HTTP/FTP get. The
byLineAsync
and byChunkAsync
functions asynchronously
perform the request given, outputting the fetched content into a range.
The low level API allows for streaming, setting request headers and cookies, and other advanced features.
Function Name | Description |
---|---|
High level | |
download | download("ftp.digitalmars.com/sieve.ds", "/tmp/downloaded-ftp-file")
downloads file from URL to file system. |
upload | upload("/tmp/downloaded-ftp-file", "ftp.digitalmars.com/sieve.ds");
uploads file from file system to URL. |
get | get("dlang.org") returns a char[] containing the dlang.org web page. |
put | put("dlang.org", "Hi") returns a char[] containing
the dlang.org web page. after a HTTP PUT of "hi" |
post | post("dlang.org", "Hi") returns a char[] containing
the dlang.org web page. after a HTTP POST of "hi" |
byLine | byLine("dlang.org") returns a range of char[] containing the
dlang.org web page. |
byChunk | byChunk("dlang.org", 10) returns a range of ubyte[10] containing the
dlang.org web page. |
byLineAsync | byLineAsync("dlang.org") asynchronously returns a range of char[] containing the dlang.org web
page. |
byChunkAsync | byChunkAsync("dlang.org", 10) asynchronously returns a range of ubyte[10] containing the
dlang.org web page. |
Low level | |
HTTP | Struct for advanced HTTP usage |
FTP | Struct for advanced FTP usage |
SMTP | Struct for advanced SMTP usage |
Example
import std .net .curl, std .stdio;
// Return a char[] containing the content specified by a URL
auto content = get("dlang.org");
// Post data and return a char[] containing the content specified by a URL
auto content = post("mydomain.com/here.cgi", ["name1" : "value1", "name2" : "value2"]);
// Get content of file from ftp server
auto content = get("ftp.digitalmars.com/sieve.ds");
// Post and print out content line by line. The request is done in another thread.
foreach (line; byLineAsync("dlang.org", "Post data"))
writeln(line);
// Get using a line range and proxy settings
auto client = HTTP();
client .proxy = "1.2.3.4";
foreach (line; byLine("dlang.org", client))
writeln(line);
For more control than the high level functions provide, use the low level API:
Example
import std .net .curl, std .stdio;
// GET with custom data receivers
auto http = HTTP("dlang.org");
http .onReceiveHeader =
(in char[] key, in char[] value) { writeln(key, ": ", value); };
http .onReceive = (ubyte[] data) { /+ drop +/ return data .length; };
http .perform();
First, an instance of the reference-counted HTTP struct is created. Then the
custom delegates are set. These will be called whenever the HTTP instance
receives a header and a data buffer, respectively. In this simple example, the
headers are written to stdout and the data is ignored. If the request is
stopped before it has finished then return something less than data.length from
the onReceive callback. See onReceiveHeader
/onReceive
for more
information. Finally, the HTTP request is performed by calling perform(), which is
synchronous.
Credits
The functionality is based on libcurl. libcurl is licensed under an MIT/X derivative license.
Functions
Name | Description |
---|---|
byChunk(url, chunkSize, conn)
|
HTTP/FTP fetch content as a range of chunks. |
byChunkAsync(url, postData, chunkSize, transmitBuffers, conn)
|
HTTP/FTP fetch content as a range of chunks asynchronously. |
byLine(url, keepTerminator, terminator, conn)
|
HTTP/FTP fetch content as a range of lines. |
byLineAsync(url, postData, keepTerminator, terminator, transmitBuffers, conn)
|
HTTP/FTP fetch content as a range of lines asynchronously. |
connect(url, conn)
|
HTTP connect request. |
del(url, conn)
|
HTTP/FTP delete content. |
download(url, saveToPath, conn)
|
HTTP/FTP download to local file system. |
get(url, conn)
|
HTTP/FTP get content. |
options(url, conn)
|
HTTP options request. |
patch(url, patchData, conn)
|
HTTP patch content. |
post(url, postData, conn)
|
HTTP post content. |
put(url, putData, conn)
|
HTTP/FTP put content. |
trace(url, conn)
|
HTTP trace request. |
upload(loadFromPath, url, conn)
|
Upload file from local files system using the HTTP or FTP protocol. |
Classes
Name | Description |
---|---|
CurlException
|
Exception thrown on errors in std.net.curl functions. |
CurlTimeoutException
|
Exception thrown on timeout errors in std.net.curl functions. |
HTTPStatusException
|
Exception thrown on HTTP request failures, e.g. 404 Not Found. |
Structs
Name | Description |
---|---|
AutoProtocol
|
|
Curl
|
Wrapper to provide a better interface to libcurl than using the plain C API.
It is recommended to use the HTTP /FTP etc. structs instead unless
raw access to libcurl is needed.
|
FTP
|
FTP client functionality. |
HTTP
|
HTTP client functionality. |
SMTP
|
Basic SMTP protocol support. |
Aliases
Name | Type | Description |
---|---|---|
CurlCode
|
int
|
Equal to CURLcode
|
ThrowOnError
|
Flag!("throwOnError")
|
Flag to specify whether or not an exception is thrown on error. |
Authors
Jonas Drewsen. Some of the SMTP code contributed by Jimmy Cao.