composer-docs/cn-introduction/articles/troubleshooting.md

Troubleshooting

This is a list of common pitfalls on using Composer, and how to avoid them.

General

1. Before asking anyone, run composer diagnose to check for common problems. If it all checks out, proceed to the next steps.

2. When facing any kind of problems using Composer, be sure to work with the latest version. See self-update for details.

3. Make sure you have no problems with your setup by running the installer's checks via curl -sS https://getcomposer.org/installer | php -- --check.

4. Ensure you're installing vendors straight from your composer.json via rm -rf vendor && composer update -v when troubleshooting, excluding any possible interferences with existing vendor installations or composer.lock entries.

Package not found

1. Double-check you don't have typos in your composer.json or repository branches and tag names.

2. Be sure to set the right minimum-stability. To get started or be sure this is no issue, set minimum-stability to "dev".

3. Packages not coming from Packagist should always be defined in the root package (the package depending on all vendors).

4. Use the same vendor and package name throughout all branches and tags of your repository, especially when maintaining a third party fork and using replace.

Package not found on travis-ci.org

1. Check the "Package not found" item above.

2. If the package tested is a dependency of one of its dependencies (cyclic dependency), the problem might be that composer is not able to detect the version of the package properly. If it is a git clone it is generally alright and Composer will detect the version of the current branch, but travis does shallow clones so that process can fail when testing pull requests and feature branches in general. The best solution is to define the version you are on via an environment variable called COMPOSER_ROOT_VERSION. You set it to dev-master for example to define the root package's version as dev-master. Use: before_script: COMPOSER_ROOT_VERSION=dev-master composer install to export the variable for the call to composer.

Need to override a package version

Let say your project depends on package A which in turn depends on a specific version of package B (say 0.1) and you need a different version of that package - version 0.11.

You can fix this by aliasing version 0.11 to 0.1:

composer.json:

{
    "require": {
        "A": "0.2",
        "B": "0.11 as 0.1"
    }
}

See aliases for more information.

Memory limit errors

If composer shows memory errors on some commands:

PHP Fatal error: Allowed memory size of XXXXXX bytes exhausted <...>

The PHP memory_limit should be increased.

Note: Composer internally increases the memory_limit to 512M. If you have memory issues when using composer, please consider creating an issue ticket so we can look into it.

To get the current memory_limit value, run:

php -r "echo ini_get('memory_limit').PHP_EOL;"

Try increasing the limit in your php.ini file (ex. /etc/php5/cli/php.ini for Debian-like systems):

; Use -1 for unlimited or define an explicit value like 512M
memory_limit = -1

Or, you can increase the limit with a command-line argument:

php -d memory_limit=-1 composer.phar <...>

"The system cannot find the path specified" (Windows)

1. Open regedit.
2. Search for an AutoRun key inside HKEY_LOCAL_MACHINE\Software\Microsoft\Command Processor or HKEY_CURRENT_USER\Software\Microsoft\Command Processor.
3. Check if it contains any path to non-existent file, if it's the case, just remove them.

API rate limit and OAuth tokens

Because of GitHub's rate limits on their API it can happen that Composer prompts for authentication asking your username and password so it can go ahead with its work.

If you would prefer not to provide your GitHub credentials to Composer you can manually create a token using the following procedure:

1. Create an OAuth token on GitHub. Read more on this.

2. Add it to the configuration running composer config -g github-oauth.github.com <oauthtoken>

Now Composer should install/update without asking for authentication.

proc_open(): fork failed errors

If composer shows proc_open() fork failed on some commands:

PHP Fatal error: Uncaught exception 'ErrorException' with message 'proc_open(): fork failed - Cannot allocate memory' in phar

This could be happening because the VPS runs out of memory and has no Swap space enabled.

free -m

total used free shared buffers cached
Mem: 2048 357 1690 0 0 237
-/+ buffers/cache: 119 1928
Swap: 0 0 0

To enable the swap you can use for example:

/bin/dd if=/dev/zero of=/var/swap.1 bs=1M count=1024
/sbin/mkswap /var/swap.1
/sbin/swapon /var/swap.1