Schedules

Creating a Schedule

A Drupal content has several properties concerning its use in the Digital Signage module:

• Priority
• Critical Flag
• Count
• Complexity

Based on theses Properties, we have to create a Schedule, which can be used for different Digital Signage vendors, like signageOS or ScreenFood. So this has to be quite generic.

A possible solution is to provide:

• a weight for the priority
• the critical flag is special and makes the priority obsolete
• a duration offset for complexity (and maybe for the critical flag as well), because complex content should be displayed longer

For example:

Complexity	Offset in seconds
is Complex	X3
is Critical	X2

For instance, the default duration is 5 seconds, a complex content will be displayed 15 seconds.

Prio	Weight
High	50
Medium	30
Low	20

The weight and the duration offset are implementation details and can be changed (see diagram below).

@startuml

class "Content" {
}

class "DSContentSettings" {
priority : Priority
count : Integer
isCritical : Boolean
isComplex : Boolean
}

class SequenceItem {
content : Content
duration : Integer
}
note left: just store reference of Content

class Schedule {
sequence : SequenceItem[]
getSequence(scheduleCalc : ScheduleCalculator, contents : Content[]) : SequenceItem[]
updateHash() : Integer
}

interface ScheduleCalculator {
calculateSequence(contents : Content[]) : SequenceItem[]
}

class DefaultScheduleCalculator {
calculateSequence(contents : Content[]) : SequenceItem[]
}

interface Weight {
getWeightByPriority(prio : Priority) : Integer
getWeightForCritical() : Integer
}

interface Duration {
{static} defaultDuration : Integer
getCriticalOffset() : Integer
getOffsetByComplexity(isComplex : Boolean) : Integer
}

ScheduleCalculator <|-- DefaultScheduleCalculator
Schedule <-- ScheduleCalculator
SequenceItem "1" -- "1" Content
Content -- DSContentSettings : have
Schedule "1" *-- "many" SequenceItem
DefaultScheduleCalculator -- Duration : use
DefaultScheduleCalculator -- Weight : use

@enduml

A default implementation can be done as follows:

node	is Critical	priority	is Complex	count	weight	offset
1	no	medium	no	infinite	30
2	yes	obsolete	no	infinite	none
3	no	low	yes	10	20	5
4	no	high	yes	infinite	50

So we have a distribution of:

• Node 1: 30%
• Node 2: special, comes in first place
• Node 3: 20%
• Node 4: 50%

Based on this, we can create a sequence. The count property is handled by the specific device. We later request a report from that device to determine how ofter the node was displayed. So we can adjust the count property.