Help:Development recommendations for easily moving to production
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Avoid pip, pecl, gems, and other language specific repositories
Please, take care when using language specific repositories, like pip, pecl, etc. The operations team avoids these like the plague because it generally involves far much more work in the long run.
In production we do not use third party repositories since we don't trust them. When we push something to production, all dependencies must be installable as debian packages, and preferably from the Ubuntu repository. If a package isn't available in the Ubuntu repository it gets packaged and stuck into our custom repository.
When using language specific repositories, it may install newer versions of libraries than available in the Ubuntu repository. Your application may then depend on the newer versions, and when we puppetize the system, the newer versions have to be backported to whichever distro version we are using.
We recommend that before using a language specific repository, that you check to see if the required library exists in the Ubuntu repository first. Unless the packaged version is too old, please use it rather than the version in the language specific repository. When using a language specific repository, please document the library that was installed, so that it can be packaged when the service is to be puppetized and deployed to production.
Document all package installations, all modified configuration files, and any commands run to configure a service
Documenting how a service is installed and configured makes the puppetization of a service much easier. It should be possible to fully puppetize a system just by reading the documentation. This also means that when a service is changed after being deployed to production that its documentation should be updated as well.
Know and document any ports and protocols in use by your service
It's important to know which ports and protocols are in use by your service, and how that affects the security of a service. Memcache, for instance, runs on 11211, and by default has no security. It's important to firewall the service, or to ensure it isn't accessible to the public. Many services have considerations like this, and documenting these makes them much easier to puppetize.