edeliver v1.8.0 Edeliver.Relup.Instructions.ResumeChannels

This upgrade instruction resumes the websocket processes

connected to phoenix channels when the upgrade is done to continue handling channel events. Use this instruction at the end of the upgrade modification if the

Edeliver.Relup.Instructions.SuspendChannels

is used at the beginning. Make sure that it is used before the

Edeliver.Relup.Instructions.ResumeRanchAcceptors

instruction to avoid that recently started websockets which were not suspendet are tried to be resumed.

Suspending and resuming websocket processes for phoenix channels requires a recent phoenix version which handles sys events for websockets. It also requires that the builtin phoenix pubsub backend Phoenix.PubSub.PG2 is used for the phoenix channels.

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arguments(instructions, config)

arguments(
  %Edeliver.Relup.Instructions{
    changed_modules: term(),
    down_instructions: term(),
    down_version: term(),
    up_instructions: term(),
    up_version: term()
  },
  Edeliver.Relup.Config.t()
) :: term()

Returns name of the application.

This name is taken as argument for the run/1 function and is required to access the acceptor processes through the supervision tree

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bulk_resume(processes, timeout \\ 1000)

bulk_resume(processes :: [pid()], timeout :: pos_integer() | :infinity) ::
  :ok
  | {:errors, count :: pos_integer(), [{pid :: pid(), reason :: term()}]}
  | :not_supported

Resumes a list of processes.

Because resume a process might take a while depending on the length of the message queue or duration of current operation processed by the pid, suspending is done asynchronously for each process by spawing a new process which calls :sys.resume/2 and then waiting for all results before returning from this function. Be careful when using :infinity as timeout, because this function might hang for infinite time if one of the process does not handle sys events.

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call_this(arguments \\ [])

call_this(arguments :: [term()]) ::
  Instruction.instruction() | Instruction.instructions()

Calls the run/1 function of this module

from the relup file during hot code upgrade

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dependencies()

dependencies() :: [instruction_module :: atom()]
dependencies() :: [Edeliver.Relup.Instructions.CheckRanchAcceptors]

This module depends on the Edeliver.Relup.Instructions.CheckRanchAcceptors and the Edeliver.Relup.Instructions.CheckRanchConnections module

which must be loaded before this instruction for upgrades and unloaded after this instruction for downgrades.

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insert_where()

insert_where() :: Instruction.insert_fun()

Callback implementation for Edeliver.Relup.RunnableInstruction.insert_where/0.

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modify_relup(instructions, config)

Callback implementation for Edeliver.Relup.Instruction.modify_relup/2.

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run(otp_application_name)

run(otp_application_name :: atom()) :: :ok

Resumes all websocket channels

to continue handling channel events after the upgrade. This is possible only in recent phoenix versions since handling sys events is required for resuming. If an older version is used, a warning is printed that suspending is not supported.