common

Documentation

Index

• func BoolPtr(v bool) *bool
• func DecisionTypePtr(t s.DecisionType) *s.DecisionType
• func EventTypePtr(t s.EventType) *s.EventType
• func Int32Ptr(v int32) *int32
• func Int64Ptr(v int64) *int64
• func StringPtr(v string) *string
• func TaskListPtr(v s.TaskList) *s.TaskList
• type TimeSource
  • func NewRealTimeSource() TimeSource
• type TokenBucket
  • func NewTokenBucket(rps int, timeSource TimeSource) TokenBucket
• type TokenBucketFactory
  • func NewTokenBucketFactory() TokenBucketFactory

Functions

func BoolPtr

func BoolPtr(v bool) *bool

BoolPtr makes a copy and returns the pointer to a string.

func DecisionTypePtr

func DecisionTypePtr(t s.DecisionType) *s.DecisionType

DecisionTypePtr makes a copy and returns the pointer to a DecisionType.

func EventTypePtr

func EventTypePtr(t s.EventType) *s.EventType

EventTypePtr makes a copy and returns the pointer to a EventType.

func Int32Ptr

func Int32Ptr(v int32) *int32

Int32Ptr makes a copy and returns the pointer to an int32.

func Int64Ptr

func Int64Ptr(v int64) *int64

Int64Ptr makes a copy and returns the pointer to an int64.

func StringPtr

func StringPtr(v string) *string

StringPtr makes a copy and returns the pointer to a string.

func TaskListPtr

func TaskListPtr(v s.TaskList) *s.TaskList

TaskListPtr makes a copy and returns the pointer to a TaskList.

Types

type TimeSource

type TimeSource interface {
	Now() time.Time
}

TimeSource is an interface for any entity that provides the current time. Its primarily used to mock out timesources in unit test

func NewRealTimeSource

func NewRealTimeSource() TimeSource

NewRealTimeSource returns a time source that servers real wall clock time using CLOCK_REALTIME

type TokenBucket

type TokenBucket interface {
	// TryConsume attempts to take count tokens from the
	// bucket. Returns true on success, false
	// otherwise along with the duration for the next refill
	TryConsume(count int) (bool, time.Duration)
	// Consume waits up to timeout duration to take count
	// tokens from the bucket. Returns true if count
	// tokens were acquired before timeout, false
	// otherwise
	Consume(count int, timeout time.Duration) bool
}

TokenBucket is the interface for any implememtation of a token bucket rate limiter

func NewTokenBucket

func NewTokenBucket(rps int, timeSource TimeSource) TokenBucket

NewTokenBucket creates and returns a new token bucket rate limiter that repelenishes the bucket every 100 milliseconds. Thread safe.

@param rps

Desired rate per second

Golang.org has an alternative implementation of the rate limiter. On benchmarking, golang's implementation was order of magnitude slower. In addition, it does a lot more than what we need. These are the benchmarks under different scenarios

BenchmarkTokenBucketParallel 50000000 40.7 ns/op BenchmarkGolangRateParallel 10000000 150 ns/op BenchmarkTokenBucketParallel-8 20000000 124 ns/op BenchmarkGolangRateParallel-8 10000000 208 ns/op BenchmarkTokenBucketParallel 50000000 37.8 ns/op BenchmarkGolangRateParallel 10000000 153 ns/op BenchmarkTokenBucketParallel-8 10000000 129 ns/op BenchmarkGolangRateParallel-8 10000000 208 ns/op

type TokenBucketFactory

type TokenBucketFactory interface {
	CreateTokenBucket(rps int, timeSource TimeSource) TokenBucket
}

TokenBucketFactory is an interface mainly used for injecting mock implementation of TokenBucket for unit testing

func NewTokenBucketFactory

func NewTokenBucketFactory() TokenBucketFactory

NewTokenBucketFactory creates an instance of factory used for creating TokenBucket instances