I attempted to install aws/aws-sdk-php yesterday on one of my Laravel 4 projects using Composer, I cannot remember exactly the chain of events but it did not in
do not do any thing only try this code if your version is 1.*:
composer self-update --2
i was facing many problem then i given memory_limit : 10G. after that i was getting same issue then i try to update composer version then it gone fix.
you can check compser version