package synchronizer

import "github.com/Diarkis/diarkis/synchronizer"

Index

Functions

func Encode

func Encode(p *Properties) ([]byte, error)

Encode encodes its data into byte array for transport and storage

Types

type EncodeData

type EncodeData struct {
	UpdateVer    uint8  `json:"updateVer"`
	RemoveVer    uint8  `json:"removeVer"`
	UpdateCmd    uint16 `json:"updateCmd"`
	RemoveCmd    uint16 `json:"removeCmd"`
	Interval     int64  `json:"interval"`
	SyncAllDelay int64  `json:"syncAllDelay"`
	TTL          int64  `json:"ttl"`
	CombineLimit int    `json:"combineLimit"`
	Encoded      []byte `json:"encoded"`
}

EncodeData is used encode Properties

type Properties

type Properties struct {
	sync.RWMutex
	// contains filtered or unexported fields
}

Properties represents synchronizer based on properties.

Property synchronizer allows its members to updated shared properties and synchronize at fixed internal in milliseconds.

Each synchronized property value will invoke the callback and the application may decide how it wants to synchronize the property. 

[IMPORTANT] If a property is updated multiple times within the time window of synchronize interval, only the last updated value of the property is synchronized.

func Decode

func Decode(encoded []byte) (*Properties, error)

Decode decodes encoded data byte array and overwrites its members with the decoded data

func NewProperties

func NewProperties(updateVer, removeVer uint8, updateCmd, removeCmd uint16, interval, syncAllDelay, ttl int64, combineLimit uint8) *Properties

NewProperties creates a new Properties instance.

Parameters 

updateVer    - Server push command version for property update.
removeVer    - Server push command version for property removal.
updateCmd    - Server push command ID for property update.
removeCmd    - Server push command ID for property removal.
interval     - Synchronization interval in milliseconds.
               Minimum value for interval is 17 milliseconds.
syncAllDelay - Delays the invocation of synchronization of all properties in milliseconds.
ttl          - TTL of property. If a property is not updated for more than TTL, it will be removed internally
               TTL is in milliseconds and the minimum allowed value is 500.
               By passing TTL lower than the minimum value of 500, you will disable TTL function for properties.
combineLimit - Maximum number of outbound synchronization packets to be combined per member.
               Default is 30.

func (*Properties) AddMember

func (p *Properties) AddMember(sid string) error

AddMember adds a user as a member to join by SID

func (*Properties) Count

func (p *Properties) Count() int

Count returns the number of existing properties

func (*Properties) GetInterval

func (p *Properties) GetInterval() int64

GetInterval returns the synchronization interval in milliseconds.

func (*Properties) IsLinkedToUser

func (p *Properties) IsLinkedToUser(key string, sid string) bool

IsLinkedToUser returns true if the given key is linked the given user SID.

func (*Properties) RemoveMember

func (p *Properties) RemoveMember(sid string) bool

RemoveMember removes a user by SID

How to remove user member when the user client disconnects: 

// "github.com/Diarkis/diarkis/user"

// This must be written to be executed when the server process starts
user.OnDiscard(func(userData *user.User) {
	// this is the user that is disconnected
	properties.RemoveMember(userData.SID)
})

func (*Properties) RemoveProperty

func (p *Properties) RemoveProperty(key string) error

RemoveProperty removes the property of the given key.

Synchronization payload format:

Fragment [1] 

+---------------------+--------------+
| size header for key | property key |
+---------------------+--------------+
|       4 bytes       |   variable   |
+---------------------+--------------+

Fragment [1] will repeat for as long as there are updated properties on every synchronization tick.

func (*Properties) Reset

func (p *Properties) Reset()

Reset clears all properties and members

func (*Properties) Start

func (p *Properties) Start() bool

Start starts the synchronization loop

func (*Properties) Stop

func (p *Properties) Stop() bool

Stop stops the synchronization loop

func (*Properties) SyncAllProperties

func (p *Properties) SyncAllProperties(sid string)

SyncAllProperties sends all existing properties to the target user by the given SID.

func (*Properties) UpdateProperty

func (p *Properties) UpdateProperty(key string, value []byte, reliable bool) error

UpdateProperty updates a property by key to be synchronize.

Synchronization payload format:

Fragment [1] 

+---------------------+--------------+-----------------------+----------------+
| size header for key | property key | size header for value | property value |
+---------------------+--------------+-----------------------+----------------+
|       1 byte        |   variable   |        1 byte         |    variable    |
+---------------------+--------------+-----------------------+----------------+

Fragment [1] will repeat for as long as there are updated properties on every synchronization tick.

func (*Properties) UpdatePropertyAsMemberProperty

func (p *Properties) UpdatePropertyAsMemberProperty(sid string, key string, value []byte, reliable bool) error

UpdatePropertyAsMemberProperty updates a property by key to be synchronize.

The property will be treated as the user's property and it will be removed when the user is removed as a member.

Synchronization payload format:

Fragment [1] 

+---------------------+--------------+-----------------------+----------------+
| size header for key | property key | size header for value | property value |
+---------------------+--------------+-----------------------+----------------+
|       1 byte        |   variable   |        1 byte         |    variable    |
+---------------------+--------------+-----------------------+----------------+

Fragment [1] will repeat for as long as there are updated properties on every synchronization tick.

func (*Properties) UpsertProperty

func (p *Properties) UpsertProperty(key string, reliable bool, cb func(exists bool, current []byte) []byte) error

UpsertProperty updates a property by key to be synchronize using existing value.

It will simply set a new value if there is no existing value for the key given.

Synchronization payload format:

Fragment [1] 

+---------------------+--------------+-----------------------+----------------+
| size header for key | property key | size header for value | property value |
+---------------------+--------------+-----------------------+----------------+
|       1 byte        |   variable   |        1 byte         |    variable    |
+---------------------+--------------+-----------------------+----------------+

Fragment [1] will repeat for as long as there are updated properties on every synchronization tick.