Hi!
I am planning to add foreman component to dovecot core and I am hoping for some feedback:
Foreman - generic per-user worker handling component
It is responsible for managing worker pools per protocol, lifecycle management of workers and handing out instances to others, as in, unix socket connections.
Each time a request is made to foreman for a worker, the worker is instantiated (if possible) and locked. Then connection is created to the socket of the worker, and the file descriptor is returned to requestor.
When the requestor has completed the task, it's responsibility is to close the DATA channel and also ask foreman to unlock the worker.
Components can register new workers using lib-foreman's API. Each worker is registered with
struct foreman_worker { const char *protocol; const char *path; const char *version; unsigned int max_instances; unsigned int max_requests; /* how many requests one worker can handle */ unsigned int max_idletime_secs; /* how long worker can idle */ unsigned int max_processtime_secs; /* how long worker can process something */ unsigned int max_lifetime_secs; /* how long a worker can live this can be exceeded if the worker has work to do. */ };
/* minimum lifetime of worker: max_idletime_secs */ /* absolute maximum lifetime of worker: max_lifetime_secs + max_processtime_secs */
The unsigned ints are optional. If they are not defined, the workers are kept until foreman exceeds the total number of workers permitted across pools.
Pools are per-worker-class pools, and are generated when a worker is registered.
Version specifies the protocol version and is going to be "1000" now. Next version will always be 1001, 1002 etc.
Any feedback or questions are welcome!
Aki