Unable to use composer for installing laraval behind proxy server in ubuntu

I am trying to install Laraval in the homestead virtual box on My Ubuntu machine which is behind proxy server and accordingly i have set the env variables

export $http_proxy="http://someip:someport"

export $https_proxy="http://someip:someport"

But when i see the output of the command below

composer diag

Output:

Checking platform settings: OK
Checking git settings: OK
Checking http connectivity to packagist: FAIL
[Composer\Downloader\TransportException] The 'http://ift.tt/1uUDdp4' URL could not be accessed: HTTP/1.0 400 Bad Request
Checking https connectivity to packagist: OK
Checking HTTP proxy: OK
Checking HTTP proxy support for request_fulluri: FAIL Unable to assess the situation, maybe packagist.org is down (The 'http://ift.tt/1uUDdp4' URL could not be accessed: HTTP/1.0 400 Bad Request)
Checking HTTPS proxy support for request_fulluri: OK
Checking github.com rate limit: OK
Checking disk free space: OK
Checking composer version: FAIL
You are not running the latest version, run `composer self-update` to update

I don't see why there is issue of connectivity.

hence these commands

composer selfupdate
composer  global require "laravel/installer"

giving such errors

The 'http://ift.tt/1UWXxAU' URL could not be accessed: HTTP/1.0 400 Bad Request


[Composer\Downloader\TransportException]The "http://ift.tt/1pxoJ8t" file could not be downloaded: failed to open stream: Network is unreachable

I have already tried these tricks.

$http_proxy=someip:someport

PHP Composer behind http proxy

Composer cannot download files

PHP Composer behind http proxy

Is there anyway i can fix this?

via Chebli Mohamed