# Module oc_stat_view # * [Description](#description) * [Data Types](#types) * [Function Index](#index) * [Function Details](#functions) View allows users to aggregate the recorded Measurements. ## Description ## Views need to be passed to the subscribe function to be before data will be collected and sent to exporters. ## Data Types ## ### aggregation() ###


aggregation() = module()

### aggregation_options() ###


aggregation_options() = any()

### description() ###


description() = binary() | string()

### measure_name() ###


measure_name() = atom() | binary() | string()

### name() ###


name() = atom() | binary() | string()

### view() ###


view() = #view{name = name() | _, measure = measure_name() | _, subscribed = boolean(), description = description() | _, ctags = oc_tags:tags() | _, tags = [oc_tags:key()] | _, aggregation = aggregation() | _, aggregation_options = aggregation_options() | _}

### view_data() ###


view_data() = #{name => name(), description => description(), ctags => oc_tags:tags(), tags => [oc_tags:key()], data => oc_stat_aggregation:data()}

## Function Index ##

deregister/1	Deregisters the view.
export/1	Returns a snapshot of the View's data.
is_registered/1	Returns true if the view is registered.
is_subscribed/1	Returns true if the view is exporting data by subscription.
new/1	Creates a View from a map.
new/5	Creates a View.
register/1	Registers the view.
register/5	Registers the view created from arguments.
subscribe/1	Subscribe the View, When subscribed, a view can aggregate measure data and export it.
subscribe/5	A shortcut: Creates, Registers, and Subscribes a view in one call.
unsubscribe/1	Unsubscribes the View.

## Function Details ## ### deregister/1 ###


deregister(View::name() | view()) -> ok

Deregisters the view. If subscribed, unsubscribes and therefore existing aggregation data cleared. Returns `{error, {unknown_view, Name}}` if the view is unknown. ### export/1 ###


export(View::view()) -> view_data()

Returns a snapshot of the View's data. ### is_registered/1 ###


is_registered(View::name() | view()) -> boolean()

Returns true if the view is registered. ### is_subscribed/1 ###


is_subscribed(View::name() | view()) -> boolean()

Returns true if the view is exporting data by subscription. ### new/1 ### `new(Map) -> any()` Creates a View from a map. ### new/5 ### `new(Name, Measure, Description, Tags, Aggregation) -> any()` Creates a View. This view needs to be registered and subscribed to a measure in order to start aggregating data. ### register/1 ###


register(View::view()) -> {ok, view()} | {error, any()}

Registers the view. Aggregation initialized with AggregationOptions. Returns `{error, {unknown_measure, Measure}}` if `Measure` is unknown.
Returns `{error, {view_already_exists, Name}}` if a view with `Name` already registered. ### register/5 ### `register(Name, Measure, Description, Tags, Aggregation) -> any()` Registers the view created from arguments. Returns `{error, {unknown_measure, Measure}}` if `Measure` is unknown.
Returns `{error, {view_already_exists, Name}}` if a view with `Name` already registered. ### subscribe/1 ###


subscribe(Map::name() | view() | map()) -> {ok, view()} | {error, any()}

Subscribe the View, When subscribed, a view can aggregate measure data and export it. Returns `{error, {unknown_view, Name}}` if `Name` view is unknown. ### subscribe/5 ### `subscribe(Name, Measure, Description, Tags, Aggregation) -> any()` A shortcut: Creates, Registers, and Subscribes a view in one call. Returns `{error, {unknown_measure, Measure}}` if `Measure` is unknown. ### unsubscribe/1 ###


unsubscribe(View::name() | view()) -> ok

Unsubscribes the View. When unsubscribed a view no longer aggregates measure data and exports it. Also all existing aggregation data cleared. Returns `{error, {unknown_view, Name}}` if `Name` view is unknown.