/ 
Tangence-0.33
River stage one • 2 direct dependents • 3 total dependents
/ Tangence::ObjectProxy

NAME

Tangence::ObjectProxy - proxy for a Tangence object in a Tangence::Client

DESCRIPTION

Instances in this class act as a proxy for an object in the Tangence::Server, allowing methods to be called, events to be subscribed to, and properties to be watched.

These objects are not directly constructed by calling the new class method; instead they are returned by methods on Tangence::Client, or by methods on other Tangence::ObjectProxy instances. Ultimately every object proxy that a client uses will come from either the proxy to the registry, or the root object.

METHODS

The following methods documented in an await expression return Future instances.

id

$id = $proxy->id;

Returns the object ID for the Tangence object being proxied for.

classname

$classname = $proxy->classname;

Returns the name of the class of the Tangence object being proxied for.

class

$class = $proxyobj->class;

Returns the Tangence::Meta::Class object representing the class of this object.

can_method

$method = $proxy->can_method( $name );

Returns the Tangence::Meta::Method object representing the named method, or undef if no such method exists.

can_event

$event = $proxy->can_event( $name );

Returns the Tangence::Meta::Event object representing the named event, or undef if no such event exists.

can_property

$property = $proxy->can_property( $name );

Returns the Tangence::Meta::Property object representing the named property, or undef if no such property exists.

call_method

$result = await $proxy->call_method( $mname, @args );

Calls the given method on the server object, passing in the given arguments. Returns a Future that will yield the method's result.

subscribe_event

await $proxy->subscribe_event( $event, %callbacks );

Subscribes to the given event on the server object, installing a callback function which will be invoked whenever the event is fired.

Takes the following named callbacks:

on_fire => CODE

Callback function to invoke whenever the event is fired

$on_fire->( @args );

The returned Future it is guaranteed to be completed before any invocation of the on_fire event handler.

unsubscribe_event

$proxy->unsubscribe_event( $event );

Removes an event subscription on the given event on the server object that was previously installed using subscribe_event.

get_property

await $value = $proxy->get_property( $prop );

Requests the current value of the property from the server object.

get_property_element

await $value = $proxy->get_property_element( $property, $index_or_key );

Requests the current value of an element of the property from the server object.

prop

$value = $proxy->prop( $property );

Returns the locally-cached value of a smashed property. If the named property is not a smashed property, an exception is thrown.

set_property

await $proxy->set_property( $prop, $value );

Sets the value of the property in the server object.

watch_property

await $proxy->watch_property( $property, %callbacks );

watch_property_with_initial

await $proxy->watch_property_with_initial( $property, %callbacks );

Watches the given property on the server object, installing callback functions which will be invoked whenever the property value changes. The latter form additionally ensures that the server will send the current value of the property as an initial update to the on_set event, atomically when it installs the update watches.

Takes the following named arguments:

on_updated => CODE

Optional. Callback function to invoke whenever the property value changes.

$on_updated->( $new_value );

If not provided, then individual handlers for individual change types must be provided.

The set of callback functions that are required depends on the type of the property. These are documented in the watch_property method of Tangence::Object.

watch_property_with_cursor

( $cursor, $first_idx, $last_idx ) =
   await $proxy->watch_property_with_cursor( $property, $from, %callbacks );

A variant of watch_property that installs a watch on the given property of the server object, and additionally returns an cursor object that can be used to lazily fetch the values stored in it.

The $from value indicates which end of the queue the cursor should start from; CUSR_FIRST to start at index 0, or CUSR_LAST to start at the highest-numbered index. The cursor is created atomically with installing the watch.

unwatch_property

$proxy->unwatch_property( $property );

Removes a property watches on the given property on the server object that was previously installed using watch_property.

CURSOR METHODS

The following methods are availilable on the property cursor objects returned by the watch_property_with_cursor method.

next_forward

( $index, @more ) = await $cursor->next_forward( $count );

next_backward

( $index, @more ) = await $cursor->next_backward( $count );

Requests the next items from the cursor. next_forward moves forwards towards higher-numbered indices, and next_backward moves backwards towards lower-numbered indices. If $count is unspecified, a default of 1 will apply.

The returned future wil yield the index of the first element returned, and the new elements. Note that there may be fewer elements returned than were requested, if the end of the queue was reached. Specifically, there will be no new elements if the cursor is already at the end.

AUTHOR

Paul Evans <leonerd@leonerd.org.uk>