Add standalone downloaders for POSIX and Windows.

[KartikSoneji]

Adds standalone downloaders for:

• POSIX systems: only hard requirement is curl (obviously) (GNU sed and base64 needed for the HydraX script).
• Windows: no additonal software required except a modern version of Windows 10.

Generates download scripts for direct links and HydraX links.
Also can generate a generic version of referrer links, but it is not currently in use.

Closes #35

Notes

• If the curl script is interrupted, it can simply be restarted, and the download will continue from where it stopped.
  Unfortunately, I could not find a way to do this for the bat script.
• The curl (not HydraX) script can easily be parallelize with GNU parallel.

[KartikSoneji]

@thorio
I wasn't able to test all edge cases, so can you please go through it once?
Do let me know if I should change anything.

[shinji257]

curl has it's own --referer option vs using the -H header option to add the header manually.

[KartikSoneji]

@shinji257 Thanks for letting me know, I will make the changes.

[Thanhcaro]

Bro, is there tool for Windows can embed hydrax.com link? I need to download some hydrax link.

[KartikSoneji]

Save this script as downloadHydraXVideo .bat

<# ::
@setlocal & copy "%~f0" "%TEMP%%~0n.ps1" >NUL && powershell -NoProfile -ExecutionPolicy Bypass -File "%TEMP%%~0n.ps1" %*
@set "ec=%ERRORLEVEL%" & del "%TEMP%%~0n.ps1"
@exit /b %ec%
#>

# downloadHydraXVideo <slug> <output file> [hd|sd]
function downloadHydraXVideo($1, $2, $3){
	$progressPreference = "silentlyContinue";
	
	$response = Invoke-WebRequest "https://ping.iamcdn.net/" `
		-UseBasicParsing `
		-Method POST `
		-Body @{slug = "$1"};
	
	
	$urlBase64 = (ConvertFrom-Json $response.Content).url;
	
    $url = [System.Text.Encoding]::UTF8.GetString(
			[System.Convert]::FromBase64String(
				$urlBase64.Chars($urlBase64.Length - 1) + $urlBase64.Substring(0, $urlBase64.Length - 1)
			)
		);
	
	if("$3" -ne "sd"){
		$url = "www." + $url;
	}
	
	Invoke-WebRequest "https://$url" `
		-UseBasicParsing `
		-Headers @{Referer = "https://playhydrax.com/?v=$1"} `
		-OutFile "$2";
	
	$progressPreference = "Continue";
}

downloadHydraXVideo $args[0] $args[1] $args[2];

Usage:

downloadHydraXVideo <slug> <output file> [hd|sd]

example
downloadHydraXVideo "GDUc-uLQN" "video.mp4" hd

[inoobbe]

hello i m new to github . i just recently saw your post here
you write some code for how to download from hydrax .
actually i don't understand how to use it . can you help me please .