Settings View Source What Gears Must Not Do

Note: This page is being updated for OSS release. Please be patient.

• (Some of the issues listed here are checked by compile.antikythera_gear_static_analysis every time you compile your gear's code.)
• Modules prefixed with Antikythera define interface functions to be used by gear implementations. On the other hand, modules with the other prefixes (AntikytheraCore, AntikytheraEal and AntikytheraLocal) are internal to antikythera and not for gear implementations. Gears must not directly depend on these antikythera-internal modules.
• All modules in a gear must be properly prefixed with the gear name, e.g. YourGear.SomeModule or Mix.Tasks.YourGear.SomeTask. Modules without correct prefixes are not allowed; they can cause name clashes.
• Dynamically creating atoms (e.g. make atoms from request bodies) is strictly prohibited as it is memory leak.
  • Atoms are stored globally within an ErlangVM and are not garbage-collected. Accumulated memory resources occupied by dynamically created atoms can result in memory issue.
  • Following code in runtime context are considered problematic:
    • String.to_atom/1 : use String.to_existing_atom/1 instead
    • Module.concat/1,2 : use Module.safe_concat/1,2 instead
    • atom expression with interpolation such as :"abc_#{foo}"
• Scheduling of Erlang processes is controlled by antikythera. Gear implementations must not disturb it by manually spawning/terminating processes.
• Accessing local file system is basically of no practical use, as they will be discarded by changes in underlying infrastructure configuration. However the following use cases are allowed:
  • Reading files in your gear's priv directory. Files in your gear's priv directory are directly copied from the git repository during compilation and thus under your control.
  • Reading/writing files within temporary directory created by Antikythera.Tmpdir.make/2.
• Writing to STDOUT/STDERR must also be avoided since these streams are used by antikythera and not for a specific gear. Use YourGear.Logger instead.