Issue with "$ composer dumpautoload" on Cloud9

I'm having an issue with Artison migrate and seeding recongnizing classes. I've read that composer dumpautoload can fix the problem but I'm now having a problem running dump-autoload on Cloud9.

When I run: $ composer dump-autoload

I get the following error: [ErrorException] file_put_contents(/home/ubuntu/workspace/vendor/composer/autoload_namespaces.php): failed to open stream: Permission denied

When I run: $ composer update

I get the following: Cannot create cache directory /home/ubuntu/.composer/cache/repo/https---packagist.org/, or directory is not writable. Proceeding without cache Cannot create cache directory /home/ubuntu/.composer/cache/files/, or directory is not writable. Proceeding without cache You are running composer with xdebug enabled. This has a major impact on runtime performance. See http://ift.tt/1NnGiU0 Loading composer repositories with package information Updating dependencies (including require-dev) - Removing symfony/yaml (v3.1.5) Update failed (Could not delete /home/ubuntu/workspace/vendor/symfony/yaml/Dumper.php: )

It looks like a problem with permissions. My question is: How do I fix these in the Cloud9 environment?

via Chebli Mohamed