NSxfer gives you the means to perform complex HTTP/HTTPS transfers from a NSIS script

• Multi threaded: transfer multiple files in parallel
• Asynchronous: start a download now, check its status later
• Aggressive: multiple attempts to connect, reconnect, resume interrupted transfers, etc.
• NSIS aware: download files at any installation stage (from .onInit callback, from Sections, from custom pages, silent installers, etc.)
• Informative: plenty of useful information is available for each transfer (size, speed, HTTP status, HTTP headers, etc)
• Supports all relevant HTTP verbs (GET, POST, PUT, HEAD, etc)
• Supports custom HTTP headers and data
• Supports proxy servers (both authenticated and open)
• Supports files larger than 4GB
• Can download remote content to RAM instead of a file
• Works well in 64-bit NSIS builds
• Many more... Check out the included readme file

• HTTP GET example:

NSxfer::Transfer /URL "https://httpbin.org/get?param1=1&param2=2" /LOCAL "$TEMP\Response.json" /END
Pop $0  ; "OK" for success

• HTTP POST application/json:

NSxfer::Transfer /URL "https://httpbin.org/post?param1=1&param2=2" /LOCAL "$TEMP\MyFile.json" /METHOD POST /DATA '{"number_of_the_beast" : 666}' /HEADERS "Content-Type: application/json" /END
Pop $0  ; "OK" for success

• HTTP POST application/x-www-form-urlencoded:

NSxfer::Transfer /URL "https://httpbin.org/post?param1=1&param2=2" /LOCAL "$TEMP\MyFile.json" /METHOD POST /DATA 'User=My+User&Pass=My+Pass' /HEADERS "Content-Type: application/x-www-form-urlencoded" /END
Pop $0  ; "OK" for success

• More complex examples in the readme file