Class: Libuv::Reactor

Inherits:
Object show all
Extended by:
Accessors, ClassMethods
Includes:
Assertions, Resource
Defined in:
lib/libuv/reactor.rb

Defined Under Namespace

Modules: ClassMethods

Constant Summary collapse

CRITICAL = 
::Mutex.new

Constants included from Accessors

Accessors::Functions

Constants included from Assertions

Assertions::MSG_NO_PROC

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from Accessors

reactor

Methods included from ClassMethods

create, current, default, new

Methods included from Resource

#check_result, #check_result!, #resolve, #to_ptr

Methods included from Assertions

#assert_block, #assert_boolean, #assert_type

Constructor Details

#initialize(pointer) ⇒ Reactor

Initialize a reactor using an FFI::Pointer to a libuv reactor



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# File 'lib/libuv/reactor.rb', line 56

def initialize(pointer) # :notnew:
    @pointer = pointer
    @reactor = self
    @run_count = 0
    @ref_count = 0
    @fiber_pool = FiberPool.new(self)

    # Create an async call for scheduling work from other threads
    @run_queue = Queue.new
    @process_queue = @reactor.async method(:process_queue_cb)
    @process_queue.unref

    # Create a next tick timer
    @next_tick = @reactor.timer method(:next_tick_cb)
    @next_tick.unref

    # Create an async call for ending the reactor
    @stop_reactor = @reactor.async method(:stop_cb)
    @stop_reactor.unref

    # Libuv can prevent the application shutting down once the main thread has ended
    # The addition of a prepare function prevents this from happening.
    @reactor_prep = Libuv::Prepare.new(@reactor, method(:noop))
    @reactor_prep.unref
    @reactor_prep.start

    # LibUV ingnores program interrupt by default.
    # We provide normal behaviour and allow this to be overriden
    @on_signal = []
    sig_callback = method(:signal_cb)
    self.signal(:INT, sig_callback).unref
    self.signal(:HUP, sig_callback).unref
    self.signal(:TERM, sig_callback).unref

    # Notify of errors
    @throw_on_exit = nil
    @reactor_notify_default = @reactor_notify = proc { |error|
        @throw_on_exit = error
    }
    @fiber_pool.on_error &@reactor_notify
end

Instance Attribute Details

#fiber_pool ⇒ Object (readonly)

Returns the value of attribute fiber_pool.



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# File 'lib/libuv/reactor.rb', line 98

def fiber_pool
  @fiber_pool
end

#run_count ⇒ Object (readonly)

Returns the value of attribute run_count.



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# File 'lib/libuv/reactor.rb', line 98

def run_count
  @run_count
end

Instance Method Details

#active_handles ⇒ Object

Return the number of active handles in the event loop



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# File 'lib/libuv/reactor.rb', line 220

def active_handles
    uvloop = Ext::UvLoop.new @pointer
    uvloop[:active_handles]
end

#all(*promises) ⇒ ::Libuv::Q::Promise

Combines multiple promises into a single promise that is resolved when all of the input promises are resolved. (thread safe)

Parameters:

  • *promises (::Libuv::Q::Promise) —

    a number of promises that will be combined into a single promise

Returns:

  • (::Libuv::Q::Promise) —

    Returns a single promise that will be resolved with an array of values, each value corresponding to the promise at the same index in the ‘promises` array. If any of the promises is resolved with a rejection, this resulting promise will be resolved with the same rejection.



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# File 'lib/libuv/reactor.rb', line 250

def all(*promises)
    Q.all(@reactor, *promises)
end

#any(*promises) ⇒ ::Libuv::Q::Promise

Combines multiple promises into a single promise that is resolved when any of the input promises are resolved.

Parameters:

  • *promises (::Libuv::Q::Promise) —

    a number of promises that will be combined into a single promise

Returns:



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# File 'lib/libuv/reactor.rb', line 260

def any(*promises)
    Q.any(@reactor, *promises)
end

#async(callback = nil, &block) ⇒ ::Libuv::Async

Get a new Async handle

Returns:



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# File 'lib/libuv/reactor.rb', line 391

def async(callback = nil, &block)
    callback ||= block
    handle = Async.new(@reactor)
    handle.progress callback if callback
    handle
end

#check(callback = nil, &blk) ⇒ ::Libuv::Check

Get a new Check handle

Returns:



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# File 'lib/libuv/reactor.rb', line 376

def check(callback = nil, &blk)
    Check.new(@reactor, callback || blk)
end

#defer ⇒ ::Libuv::Q::Deferred

Creates a deferred result object for where the result of an operation may only be returned at some point in the future or is being processed on a different thread (thread safe)

Returns:



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# File 'lib/libuv/reactor.rb', line 238

def defer
    Q.defer(@reactor)
end

#exec ⇒ Object

Execute the provided block of code in a fiber from the pool



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# File 'lib/libuv/reactor.rb', line 199

def exec
    @fiber_pool.exec { yield }
end

#file(path, flags = 0, mode: 0, **opts, &blk) ⇒ ::Libuv::File

Opens a file and returns an object that can be used to manipulate it

Parameters:

  • path (String) —

    the path to the file or folder for watching

  • flags (Integer) (defaults to: 0) —

    see ruby File::Constants

  • mode (Integer) (defaults to: 0)

Returns:



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# File 'lib/libuv/reactor.rb', line 458

def file(path, flags = 0, mode: 0, **opts, &blk)
    assert_type(String, path, "path must be a String")
    assert_type(Integer, flags, "flags must be an Integer")
    assert_type(Integer, mode, "mode must be an Integer")
    File.new(@reactor, path, flags, mode: mode, **opts, &blk)
end

#filesystem ⇒ ::Libuv::Filesystem

Returns an object for manipulating the filesystem

Returns:



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# File 'lib/libuv/reactor.rb', line 468

def filesystem
    Filesystem.new(@reactor)
end

#finally(*promises) ⇒ ::Libuv::Q::Promise

Combines multiple promises into a single promise that is resolved when all of the input promises are resolved or rejected.

Parameters:

  • *promises (::Libuv::Q::Promise) —

    a number of promises that will be combined into a single promise

Returns:

  • (::Libuv::Q::Promise) —

    Returns a single promise that will be resolved with an array of values, each [result, wasResolved] value pair corresponding to a at the same index in the ‘promises` array.



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# File 'lib/libuv/reactor.rb', line 271

def finally(*promises)
    Q.finally(@reactor, *promises)
end

#fs_event(path) ⇒ ::Libuv::FSEvent

Get a new FSEvent instance

Parameters:

  • path (String) —

    the path to the file or folder for watching

Returns:

Raises:

  • (ArgumentError) —

    if path is not a string



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# File 'lib/libuv/reactor.rb', line 447

def fs_event(path)
    assert_type(String, path)
    FSEvent.new(@reactor, path)
end

#handle ⇒ Object 



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# File 'lib/libuv/reactor.rb', line 157

def handle; @pointer; end

#idle(callback = nil, &block) ⇒ ::Libuv::Idle

Get a new Idle handle

Parameters:

  • callback (Proc) (defaults to: nil) —

    the callback to be called on idle trigger

Returns:



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# File 'lib/libuv/reactor.rb', line 384

def idle(callback = nil, &block)
    Idle.new(@reactor, callback || block)
end

#inspect ⇒ Object

Overwrite as errors in jRuby can literally hang VM when inspecting as many many classes will reference this class



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# File 'lib/libuv/reactor.rb', line 152

def inspect
    "#<#{self.class}:0x#{self.__id__.to_s(16)} NT=#{@run_queue.length}>"
end

#log(error, msg = nil, trace = nil) ⇒ Object

Notifies the reactor there was an event that should be logged

Parameters:

  • error (Exception) —

    the error

  • msg (String|nil) (defaults to: nil) —

    optional context on the error

  • trace (Array<String>) (defaults to: nil) —

    optional additional trace of caller if async



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# File 'lib/libuv/reactor.rb', line 513

def log(error, msg = nil, trace = nil)
    @reactor_notify.call(error, msg, trace)
end

#lookup(hostname, hint = :IPv4, port = 9, wait: true, &block) ⇒ ::Libuv::Dns

Lookup a hostname

Parameters:

  • hostname (String) —

    the domain name to lookup

  • port (Integer, String) (defaults to: 9) —

    the service being connected too

  • callback (Proc) —

    the callback to be called on success

Returns:



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# File 'lib/libuv/reactor.rb', line 432

def lookup(hostname, hint = :IPv4, port = 9, wait: true, &block)
    dns = Dns.new(@reactor, hostname, port, hint, wait: wait)    # Work is a promise object
    if block_given? || !wait
        dns.then block
        dns
    else
        dns.results
    end
end

#lookup_error(err) ⇒ ::Libuv::Error

Lookup an error code and return is as an error object

Parameters:

  • err (Integer) —

    The error code to look up.

Returns:



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# File 'lib/libuv/reactor.rb', line 301

def lookup_error(err)
    name = ::Libuv::Ext.err_name(err)

    if name
        msg  = ::Libuv::Ext.strerror(err)
        ::Libuv::Error.const_get(name.to_sym).new("#{msg}, #{name}:#{err}")
    else
        # We want a back-trace in this case
        raise "error lookup failed for code #{err}"
    end
rescue Exception => e
    @reactor.log e, 'performing error lookup'
    e
end

#next_tick(&block) ⇒ Object

Queue some work to be processed in the next iteration of the event reactor (thread safe)

Parameters:

  • callback (Proc) —

    the callback to be called on the reactor thread



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# File 'lib/libuv/reactor.rb', line 492

def next_tick(&block)
    @run_queue << block
    if reactor_thread?
        # Create a next tick timer
        if not @next_tick_scheduled
            @next_tick.start(0)
            @next_tick_scheduled = true
            @next_tick.ref
        end
    else
        @process_queue.call
    end

    self
end

#notifier(callback = nil, &blk) ⇒ ::Libuv::Q::Promise

Provides a promise notifier for receiving un-handled exceptions

Returns:



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# File 'lib/libuv/reactor.rb', line 229

def notifier(callback = nil, &blk)
    @reactor_notify = callback || blk || @reactor_notify_default
    self
end

#now ⇒ Integer

Get current time in milliseconds

Returns:

  • (Integer) 


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# File 'lib/libuv/reactor.rb', line 293

def now
    ::Libuv::Ext.now(@pointer)
end

#on_program_interrupt(callback = nil, &block) ⇒ Object

Allows user defined behaviour when sig int is received



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# File 'lib/libuv/reactor.rb', line 410

def on_program_interrupt(callback = nil, &block)
    @on_signal << (callback || block)
    self
end

#pipe(ipc = false) ⇒ ::Libuv::Pipe

Get a new Pipe instance

Parameters:

  • ipc (true, false) (defaults to: false) —

    indicate if a handle will be used for ipc, useful for sharing tcp socket between processes

Returns:



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# File 'lib/libuv/reactor.rb', line 354

def pipe(ipc = false)
    Pipe.new(@reactor, ipc)
end

#prepare(callback = nil, &blk) ⇒ ::Libuv::Prepare

Get a new Prepare handle

Returns:



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# File 'lib/libuv/reactor.rb', line 369

def prepare(callback = nil, &blk)
    Prepare.new(@reactor, callback || blk)
end

#reactor_running? ⇒ Boolean Also known as: running?

Tells you whether the Libuv reactor reactor is currently running.

Returns:

  • (Boolean) 


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# File 'lib/libuv/reactor.rb', line 532

def reactor_running?
    @reactor_running
end

#reactor_thread? ⇒ Boolean

True if the calling thread is the same thread as the reactor.

Returns:

  • (Boolean) 


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# File 'lib/libuv/reactor.rb', line 525

def reactor_thread?
    self == Thread.current.thread_variable_get(:reactor)
end

#ref ⇒ Object

Prevents the reactor loop from stopping



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# File 'lib/libuv/reactor.rb', line 204

def ref
    if reactor_thread? && reactor_running?
        @process_queue.ref if @ref_count == 0
        @ref_count += 1
    end
end

#reject(reason) ⇒ Object

Creates a promise that is resolved as rejected with the specified reason. This api should be used to forward rejection in a chain of promises. If you are dealing with the last promise in a promise chain, you don’t need to worry about it.



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# File 'lib/libuv/reactor.rb', line 278

def reject(reason)
    Q.reject(@reactor, reason)
end

#run(run_type = :UV_RUN_DEFAULT) {|promise| ... } ⇒ Object

Run the actual event reactor. This method will block until the reactor is stopped.

Parameters:

  • run_type (:UV_RUN_DEFAULT, :UV_RUN_ONCE, :UV_RUN_NOWAIT) (defaults to: :UV_RUN_DEFAULT)

Yield Parameters:

  • promise (::Libuv::Q::Promise) —

    Yields a promise that can be used for logging unhandled exceptions on the reactor.



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# File 'lib/libuv/reactor.rb', line 164

def run(run_type = :UV_RUN_DEFAULT)
    if not @reactor_running
        begin
            @reactor_running = true
            raise 'only one reactor allowed per-thread' if Thread.current.thread_variable_get(:reactor)

            Thread.current.thread_variable_set(:reactor, @reactor)
            @throw_on_exit = nil
            update_time
            @fiber_pool.reset
            @fiber_pool.exec { yield @reactor } if block_given?
            @run_count += 1
            ::Libuv::Ext.run(@pointer, run_type)  # This is blocking
        ensure
            Thread.current.thread_variable_set(:reactor, nil)
            @reactor_running = false
            @run_queue.clear
        end

        # Raise the last unhandled error to occur on the reactor thread
        raise @throw_on_exit if @throw_on_exit

    elsif block_given?
        if reactor_thread?
            update_time
            yield @reactor
        else
            raise 'reactor already running on another thread'
        end
    end

    @reactor
end

#schedule { ... } ⇒ Object

Schedule some work to be processed on the event reactor as soon as possible (thread safe)

Yields:

  • the callback to be called on the reactor thread



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# File 'lib/libuv/reactor.rb', line 479

def schedule
    if reactor_thread?
        yield
    else
        @run_queue << Proc.new
        @process_queue.call
    end
    self
end

#signal(signum = nil, callback = nil, &block) ⇒ ::Libuv::Signal

Get a new signal handler

Returns:



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# File 'lib/libuv/reactor.rb', line 401

def signal(signum = nil, callback = nil, &block)
    callback ||= block
    handle = Signal.new(@reactor)
    handle.progress callback if callback
    handle.start(signum) if signum
    handle
end

#sleep(msecs) ⇒ Object 



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# File 'lib/libuv/reactor.rb', line 316

def sleep(msecs)
    fiber = Fiber.current
    time = timer {
        time.close
        fiber.resume
    }.start(msecs)
    Fiber.yield
end

#spawn(cmd, **args) ⇒ Object 



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# File 'lib/libuv/reactor.rb', line 472

def spawn(cmd, **args)
    Spawn.new(@reactor, cmd, **args)
end

#stop ⇒ Object

Closes handles opened by the reactor class and completes the current reactor iteration (thread safe)



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# File 'lib/libuv/reactor.rb', line 518

def stop
    @stop_reactor.call
end

#tcp(callback = nil, **opts, &blk) ⇒ ::Libuv::TCP

Get a new TCP instance

Returns:



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# File 'lib/libuv/reactor.rb', line 328

def tcp(callback = nil, **opts, &blk)
    TCP.new(@reactor, progress: callback || blk, **opts)
end

#timer(callback = nil, &blk) ⇒ ::Libuv::Timer

Get a new timer instance

Parameters:

  • callback (Proc) (defaults to: nil) —

    the callback to be called on timer trigger

Returns:



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# File 'lib/libuv/reactor.rb', line 362

def timer(callback = nil, &blk)
    Timer.new(@reactor, callback || blk)
end

#tty(fileno, readable = false) ⇒ ::Libuv::TTY

Get a new TTY instance

Parameters:

  • fileno (Integer) —

    Integer file descriptor of a tty device

  • readable (true, false) (defaults to: false) —

    Boolean indicating if TTY is readable

Returns:



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# File 'lib/libuv/reactor.rb', line 344

def tty(fileno, readable = false)
    assert_type(Integer, fileno, "io#fileno must return an integer file descriptor, #{fileno.inspect} given")

    TTY.new(@reactor, fileno, readable)
end

#udp(callback = nil, **opts, &blk) ⇒ ::Libuv::UDP

Get a new UDP instance

Returns:



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# File 'lib/libuv/reactor.rb', line 335

def udp(callback = nil, **opts, &blk)
    UDP.new(@reactor, progress: callback || blk, **opts)
end

#unref ⇒ Object

Allows the reactor loop to stop



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# File 'lib/libuv/reactor.rb', line 212

def unref
    if reactor_thread? && reactor_running? && @ref_count > 0
        @ref_count -= 1
        @process_queue.unref if @ref_count == 0
    end
end

#update_time ⇒ Object

forces reactor time update, useful for getting more granular times

Returns:

  • nil



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# File 'lib/libuv/reactor.rb', line 285

def update_time
    ::Libuv::Ext.update_time(@pointer)
    self
end

#work(callback = nil, &block) ⇒ ::Libuv::Work

Queue some work for processing in the libuv thread pool

Parameters:

  • callback (Proc) (defaults to: nil) —

    the callback to be called in the thread pool

Returns:

Raises:

  • (ArgumentError) —

    if block is not given



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# File 'lib/libuv/reactor.rb', line 420

def work(callback = nil, &block)
    callback ||= block
    assert_block(callback)
    Work.new(@reactor, callback)    # Work is a promise object
end