cloud security

I have several questions concerning security in the cloud: 1 If a process e.g. the e-mail module sends an e-mail how does it get permission to actually send the mail. If I have a custom-java action how do i get permission to read/write files. If I change code in a module loaded from the app store (e.g. excel importer), will I get security issues (for reading in this case)
1 answers

You can write files to appropriate locations, such as a temp directory. You can get a reference to this directory by calling

File tempDirectory = Core.getConfiguration().getTempPath()

There are no restrictions on this directory, so no need to ask for permissions.