Aphora v1.0.0 Aphora.Worker View Source
Aphora.Worker implements a GenServer, which can generate guaranteed unique Aphora.id/0 on demand.
Link to this section Summary
Functions
Returns the unique Aphora.id/0.
Returns a specification to start this module under a supervisor.
Invoked when the server is started. start_link/3 or start/3 will
block until it returns.
Returns the Aphora.timestamp/0.
Link to this section Functions
build_id(state)
View Source
(since 0.1.0)
build_id(%{
datacenter: Aphora.datacenter(),
worker: Aphora.worker(),
timestamp: Aphora.timestamp(),
counter: Aphora.counter()
}) :: Aphora.id()
build_id(%{
datacenter: Aphora.datacenter(),
worker: Aphora.worker(),
timestamp: Aphora.timestamp(),
counter: Aphora.counter()
}) :: Aphora.id()
Returns the unique Aphora.id/0.
It first combines the binary representation of the information within the state into a 72 Bits binary.
Afterwards it gets encoded using Aphora.Helper.encode/1, so it can be easily used for any URI.
Examples
iex> Aphora.Worker.build_id(%{datacenter: 2, worker: 423, timestamp: 912_988_800_000, counter: 1207})
"0eHHz1--abHr"
child_spec(init_arg) View Source
Returns a specification to start this module under a supervisor.
See Supervisor.
init(state) View Source
Invoked when the server is started. start_link/3 or start/3 will
block until it returns.
init_arg is the argument term (second argument) passed to start_link/3.
Returning {:ok, state} will cause start_link/3 to return
{:ok, pid} and the process to enter its loop.
Returning {:ok, state, timeout} is similar to {:ok, state}
except handle_info(:timeout, state) will be called after timeout
milliseconds if no messages are received within the timeout.
Returning {:ok, state, :hibernate} is similar to {:ok, state}
except the process is hibernated before entering the loop. See
c:handle_call/3 for more information on hibernation.
Returning {:ok, state, {:continue, continue}} is similar to
{:ok, state} except that immediately after entering the loop
the c:handle_continue/2 callback will be invoked with the value
continue as first argument.
Returning :ignore will cause start_link/3 to return :ignore and
the process will exit normally without entering the loop or calling
c:terminate/2. If used when part of a supervision tree the parent
supervisor will not fail to start nor immediately try to restart the
GenServer. The remainder of the supervision tree will be started
and so the GenServer should not be required by other processes.
It can be started later with Supervisor.restart_child/2 as the child
specification is saved in the parent supervisor. The main use cases for
this are:
- The
GenServeris disabled by configuration but might be enabled later. - An error occurred and it will be handled by a different mechanism than the
Supervisor. Likely this approach involves callingSupervisor.restart_child/2after a delay to attempt a restart.
Returning {:stop, reason} will cause start_link/3 to return
{:error, reason} and the process to exit with reason reason without
entering the loop or calling c:terminate/2.
Callback implementation for GenServer.init/1.
start_link(state) View Source
timestamp(epoch)
View Source
(since 0.1.0)
timestamp(Aphora.epoch()) :: Aphora.timestamp()
timestamp(Aphora.epoch()) :: Aphora.timestamp()
Returns the Aphora.timestamp/0.
It gets calculated by taking the current time System.os_time/1 and substracting the Aphora.epoch/0 of it.
Examples
iex> Aphora.Worker.timestamp(0) == System.os_time(:millisecond)
true