govec

Basic example of GoVectors key functions

package main

import (
	"fmt"

	"github.com/DistributedClocks/GoVector/govec"
)

func main() {
	//Initialize logger with default configuration. This can be done in
	//a var block to ensure that GoVector is initialized at boot time.
	Logger := govec.InitGoVector("MyProcess", "LogFile", govec.GetDefaultConfig())
	opts := govec.GetDefaultLogOptions()

	//An example message
	messagepayload := []byte("samplepayload")

	//Prior to sending a message, call PrepareSend on the payload to
	//encode the payload and append this processes vector clock to the
	//payload
	encodedVCpayload := Logger.PrepareSend("Sending Message", messagepayload, opts)

	//encodedVCpayload is ready to be written to the network
	//ex) conn.Write(encodedVCpayload)

	//Receiving Example
	//First allocate a buffer to receive a message into. This must be
	//the same type as the encoded message. Here incommingMessage and
	//messagepayload are the same type []byte.
	var incommingMessage []byte

	//Prior to unpacking call a message must be received
	//ex) conn.Read(encodedVCPayload)

	//Call UnpackReceive on received messages to update local vector
	//clock values, and decode the original message.
	Logger.UnpackReceive("Received Message from server", encodedVCpayload, &incommingMessage, opts)
	fmt.Printf("Received Message: %s\n", incommingMessage)

	//Important local events can be timestamped with vector clocks
	//using LogLocalEvent, which also increments the local clock.
	Logger.LogLocalEvent("Example Complete", opts)

}

Output:

Received Message: samplepayload

Logging with priority trims all events which are lower from the specified priority from the log. This functionality is useful for isolating behaviour such as recovery protocols, from common behaviour like heartbeats.

package main

import (
	"github.com/DistributedClocks/GoVector/govec"
)

func main() {
	//Access GoVectors default configureation, and set priority
	config := govec.GetDefaultConfig()
	config.Priority = govec.DEBUG
	config.PrintOnScreen = true
	//Initialize GoVector
	Logger := govec.InitGoVector("MyProcess", "PrioritisedLogFile", config)
	opts := govec.GetDefaultLogOptions()

	Logger.LogLocalEvent("Debug Priority Event", opts.SetPriority(govec.DEBUG))
	Logger.LogLocalEvent("Info Priority Event", opts.SetPriority(govec.INFO))
	Logger.LogLocalEvent("Warning Priority Event", opts.SetPriority(govec.WARNING))
	Logger.LogLocalEvent("Error Priority Event", opts.SetPriority(govec.ERROR))
	Logger.LogLocalEvent("Fatal Priority Event", opts.SetPriority(govec.FATAL))

	//BUG Output contains timestamps so it cant be tested with *******
	//comments
	//Debug Priority Event
	//Info Priority Event
	//Warning Priority Event
	//Error Priority Event
	//Fatal Priority Event
}

Output:

GoVector logs can be used to associate real time events for visualization with TSViz

package main

import (
	"fmt"

	"github.com/DistributedClocks/GoVector/govec"
)

func main() {
	//Access config and set timestamps (realtime) to true
	config := govec.GetDefaultConfig()
	config.UseTimestamps = true
	//Initalize GoVector
	Logger := govec.InitGoVector("MyProcess", "LogFile", config)
	opts := govec.GetDefaultLogOptions()

	//In Sending Process

	//Prepare a Message
	messagepayload := []byte("samplepayload")
	finalsend := Logger.PrepareSend("Sending Message", messagepayload, opts)
	//In Receiving Process

	//receive message
	var incommingMessage []byte
	Logger.UnpackReceive("Received Message from server", finalsend, &incommingMessage, opts)
	fmt.Printf("Received Message: %s\n", incommingMessage)
	//Can be called at any point
	Logger.LogLocalEvent("Example Complete", opts)

}

Output:

Received Message: samplepayload