Merge https://github.com/weichou1229/go-patterns

# Conflicts:
#	README.md

.gitignore

@@ -32,3 +32,4 @@ _testmain.go
 
 # Output of the go coverage tool, specifically when used with LiteIDE
 *.out
+*.orig

README.md

@@ -15,96 +15,96 @@ A curated collection of idiomatic design & application patterns for Go language.
 
 | Pattern | Description | Status |
 |:-------:|:----------- |:------:|
-| [Abstract Factory](/creational/abstract_factory.md) | Provides an interface for creating families of releated objects | ✘ |
+| [Abstract Factory](/creational/abstract_factory.md) | Provides an interface for creating families of releated objects | âœ|
-| [Builder](/creational/builder.md) | Builds a complex object using simple objects | ✔ |
+| [Builder](/creational/builder.md) | Builds a complex object using simple objects | âœ|
-| [Factory Method](/creational/factory.md) | Defers instantiation of an object to a specialized function for creating instances | ✔ |
+| [Factory Method](/creational/factory.md) | Defers instantiation of an object to a specialized function for creating instances | âœ|
-| [Object Pool](/creational/object-pool.md) | Instantiates and maintains a group of objects instances of the same type | ✔ |
+| [Object Pool](/creational/object-pool.md) | Instantiates and maintains a group of objects instances of the same type | âœ|
-| [Singleton](/creational/singleton.md) | Restricts instantiation of a type to one object | ✔ |
+| [Singleton](/creational/singleton.md) | Restricts instantiation of a type to one object | âœ|
 
 ## Structural Patterns
 
 | Pattern | Description | Status |
 |:-------:|:----------- |:------:|
-| [Bridge](/structural/bridge/main.go) | Decouples an interface from its implementation so that the two can vary independently | ✔ |
+| [Bridge](/structural/bridge/main.go) | Decouples an interface from its implementation so that the two can vary independently | âœ|
-| [Composite](/structural/composite/main.go) | Encapsulates and provides access to a number of different objects | ✔ |
+| [Composite](/structural/composite/main.go) | Encapsulates and provides access to a number of different objects | âœ|
-| [Decorator](/structural/decorator.md) | Adds behavior to an object, statically or dynamically | ✔ |
+| [Decorator](/structural/decorator.md) | Adds behavior to an object, statically or dynamically | âœ|
-| [Facade](/structural/facade/main.go) | Uses one type as an API to a number of others | ✔ |
+| [Facade](/structural/facade/main.go) | Uses one type as an API to a number of others | âœ|
-| [Flyweight](/structural/flyweight/main.go) | Reuses existing instances of objects with similar/identical state to minimize resource usage | ✔ |
+| [Flyweight](/structural/flyweight/main.go) | Reuses existing instances of objects with similar/identical state to minimize resource usage | âœ|
-| [Proxy](/structural/proxy.md) | Provides a surrogate for an object to control it's actions | ✔ |
+| [Proxy](/structural/proxy.md) | Provides a surrogate for an object to control it's actions | âœ|
 
 ## Behavioral Patterns
 
 | Pattern | Description | Status |
 |:-------:|:----------- |:------:|
-| [Chain of Responsibility](/behavioral/chain_of_responsibility/main.go) | Avoids coupling a sender to receiver by giving more than object a chance to handle the request | ✔ |
+| [Chain of Responsibility](/behavioral/chain_of_responsibility/main.go) | Avoids coupling a sender to receiver by giving more than object a chance to handle the request | âœ|
-| [Command](/behavioral/command/main.go) | Bundles a command and arguments to call later | ✔ |
+| [Command](/behavioral/command/main.go) | Bundles a command and arguments to call later | âœ|
-| [Mediator](/behavioral/mediator/main.go) | Connects objects and acts as a proxy | ✔ |
+| [Mediator](/behavioral/mediator/main.go) | Connects objects and acts as a proxy | âœ|
-| [Memento](/behavioral/memento/main.go) | Generate an opaque token that can be used to go back to a previous state | ✔ |
+| [Memento](/behavioral/memento/main.go) | Generate an opaque token that can be used to go back to a previous state | âœ|
-| [Observer](/behavioral/observer.md) | Provide a callback for notification of events/changes to data | ✔ |
+| [Observer](/behavioral/observer.md) | Provide a callback for notification of events/changes to data | âœ|
-| [Registry](/behavioral/registry.md) | Keep track of all subclasses of a given class | ✘ |
+| [Registry](/behavioral/registry.md) | Keep track of all subclasses of a given class | âœ|
-| [State](/behavioral/state/main.go) | Encapsulates varying behavior for the same object based on its internal state | ✔ |
+| [State](/behavioral/state/main.go) | Encapsulates varying behavior for the same object based on its internal state | âœ|
-| [Strategy](/behavioral/strategy.md) | Enables an algorithm's behavior to be selected at runtime | ✔ |
+| [Strategy](/behavioral/strategy.md) | Enables an algorithm's behavior to be selected at runtime | âœ|
-| [Template](/behavioral/template/main.go) | Defines a skeleton class which defers some methods to subclasses | ✔ |
+| [Template](/behavioral/template/main.go) | Defines a skeleton class which defers some methods to subclasses | âœ|
-| [Visitor](/behavioral/visitor/main.go) | Separates an algorithm from an object on which it operates | ✔ |
+| [Visitor](/behavioral/visitor/main.go) | Separates an algorithm from an object on which it operates | âœ|
 
 ## Synchronization Patterns
 
 | Pattern | Description | Status |
 |:-------:|:----------- |:------:|
-| [Condition Variable](/synchronization/condition_variable.md) | Provides a mechanism for threads to temporarily give up access in order to wait for some condition | ✘ |
+| [Condition Variable](/synchronization/condition_variable.md) | Provides a mechanism for threads to temporarily give up access in order to wait for some condition | âœ|
-| [Lock/Mutex](/synchronization/mutex.md) | Enforces mutual exclusion limit on a resource to gain exclusive access | ✘ |
+| [Lock/Mutex](/synchronization/mutex.md) | Enforces mutual exclusion limit on a resource to gain exclusive access | âœ|
-| [Monitor](/synchronization/monitor.md) | Combination of mutex and condition variable patterns | ✘ |
+| [Monitor](/synchronization/monitor.md) | Combination of mutex and condition variable patterns | âœ|
-| [Read-Write Lock](/synchronization/read_write_lock.md) | Allows parallel read access, but only exclusive access on write operations to a resource | ✘ |
+| [Read-Write Lock](/synchronization/read_write_lock.md) | Allows parallel read access, but only exclusive access on write operations to a resource | âœ|
-| [Semaphore](/synchronization/semaphore.md) | Allows controlling access to a common resource | ✔ |
+| [Semaphore](/synchronization/semaphore.md) | Allows controlling access to a common resource | âœ|
 
 ## Concurrency Patterns
 
 | Pattern | Description | Status |
 |:-------:|:----------- |:------:|
-| [N-Barrier](/concurrency/n_barrier/main.go) | Prevents a process from proceeding until all N processes reach to the barrier | ✔ |
+| [N-Barrier](/concurrency/n_barrier/main.go) | Prevents a process from proceeding until all N processes reach to the barrier | âœ|
-| [Bounded Parallelism](/concurrency/bounded_parallelism.md) | Completes large number of independent tasks with resource limits | ✔ |
+| [Bounded Parallelism](/concurrency/bounded/bounded_parallelism.md) | Completes large number of independent tasks with resource limits | âœ|
-| [Broadcast](/concurrency/broadcast.md) | Transfers a message to all recipients simultaneously | ✘ |
+| [Broadcast](/concurrency/broadcast.md) | Transfers a message to all recipients simultaneously | âœ|
-| [Coroutines](/concurrency/coroutine.md) | Subroutines that allow suspending and resuming execution at certain locations | ✘ |
+| [Coroutines](/concurrency/coroutine.md) | Subroutines that allow suspending and resuming execution at certain locations | âœ|
-| [Generators](/concurrency/generator.md) | Yields a sequence of values one at a time | ✔ |
+| [Generators](/concurrency/generator.md) | Yields a sequence of values one at a time | âœ|
-| [Reactor](/concurrency/reactor.md) | Demultiplexes service requests delivered concurrently to a service handler and dispatches them syncronously to the associated request handlers | ✘ |
+| [Reactor](/concurrency/reactor.md) | Demultiplexes service requests delivered concurrently to a service handler and dispatches them syncronously to the associated request handlers | âœ|
-| [Parallelism](/concurrency/parallelism.md) | Completes large number of independent tasks | ✔ |
+| [Parallelism](/concurrency/parallelism.md) | Completes large number of independent tasks | âœ|
-| [Producer Consumer](/concurrency/producer_consumer.md) | Separates tasks from task executions | ✘ |
+| [Producer Consumer](/concurrency/producer_consumer.md) | Separates tasks from task executions | âœ|
 
 ## Messaging Patterns
 
 | Pattern | Description | Status |
 |:-------:|:----------- |:------:|
-| [Fan-In](/messaging/fan_in.md) | Funnels tasks to a work sink (e.g. server) | ✔ |
+| [Fan-In](/messaging/fan_in.md) | Funnels tasks to a work sink (e.g. server) | âœ|
-| [Fan-Out](/messaging/fan_out.md) | Distributes tasks among workers (e.g. producer) | ✔ |
+| [Fan-Out](/messaging/fan_out.md) | Distributes tasks among workers (e.g. producer) | âœ|
-| [Futures & Promises](/messaging/futures_promises.md) | Acts as a place-holder of a result that is initially unknown for synchronization purposes | ✘ |
+| [Futures & Promises](/messaging/futures_promises.md) | Acts as a place-holder of a result that is initially unknown for synchronization purposes | âœ|
-| [Publish/Subscribe](/messaging/publish_subscribe.md) | Passes information to a collection of recipients who subscribed to a topic | ✔ |
+| [Publish/Subscribe](/messaging/publish_subscribe.md) | Passes information to a collection of recipients who subscribed to a topic | âœ|
-| [Push & Pull](/messaging/push_pull.md) | Distributes messages to multiple workers, arranged in a pipeline | ✘ |
+| [Push & Pull](/messaging/push_pull.md) | Distributes messages to multiple workers, arranged in a pipeline | âœ|
 
 ## Stability Patterns
 
 | Pattern | Description | Status |
 |:-------:|:----------- |:------:|
-| [Bulkheads](/stability/bulkhead.md)  | Enforces a principle of failure containment (i.e. prevents cascading failures) | ✘ |
+| [Bulkheads](/stability/bulkhead.md)  | Enforces a principle of failure containment (i.e. prevents cascading failures) | âœ|
-| [Circuit-Breaker](/stability/circuit-breaker.md) | Stops the flow of the requests when requests are likely to fail | ✔ |
+| [Circuit-Breaker](/stability/circuit-breaker.md) | Stops the flow of the requests when requests are likely to fail | âœ|
-| [Deadline](/stability/deadline.md) | Allows clients to stop waiting for a response once the probability of response becomes low (e.g. after waiting 10 seconds for a page refresh) | ✘ |
+| [Deadline](/stability/deadline.md) | Allows clients to stop waiting for a response once the probability of response becomes low (e.g. after waiting 10 seconds for a page refresh) | âœ|
-| [Fail-Fast](/stability/fail_fast.md) | Checks the availability of required resources at the start of a request and fails if the requirements are not satisfied | ✘ |
+| [Fail-Fast](/stability/fail_fast.md) | Checks the availability of required resources at the start of a request and fails if the requirements are not satisfied | âœ|
-| [Handshaking](/stability/handshaking.md) | Asks a component if it can take any more load, if it can't, the request is declined | ✘ |
+| [Handshaking](/stability/handshaking.md) | Asks a component if it can take any more load, if it can't, the request is declined | âœ|
-| [Steady-State](/stability/steady_state.md) | For every service that accumulates a resource, some other service must recycle that resource | ✘ |
+| [Steady-State](/stability/steady_state.md) | For every service that accumulates a resource, some other service must recycle that resource | âœ|
 
 ## Profiling Patterns
 
 | Pattern | Description | Status |
 |:-------:|:----------- |:------:|
-| [Timing Functions](/profiling/timing.md) | Wraps a function and logs the execution | ✔ |
+| [Timing Functions](/profiling/timing.md) | Wraps a function and logs the execution | âœ|
 
 ## Idioms
 
 | Pattern | Description | Status |
 |:-------:|:----------- |:------:|
-| [Functional Options](/idiom/functional-options.md) | Allows creating clean APIs with sane defaults and idiomatic overrides | ✔ |
+| [Functional Options](/idiom/functional-options.md) | Allows creating clean APIs with sane defaults and idiomatic overrides | âœ|
 
 ## Anti-Patterns
 
 | Pattern | Description | Status |
 |:-------:|:----------- |:------:|
-| [Cascading Failures](/anti-patterns/cascading_failures.md) | A failure in a system of interconnected parts in which the failure of a part causes a domino effect | ✘ |
+| [Cascading Failures](/anti-patterns/cascading_failures.md) | A failure in a system of interconnected parts in which the failure of a part causes a domino effect | âœ|

SUMMARY.md

@@ -33,7 +33,7 @@
     * [Semaphore](/synchronization/semaphore.md)
   * [Concurrency Patterns](/README.md#concurrency-patterns)
     * [N-Barrier](/concurrency/barrier.md)
-    * [Bounded Parallelism](/concurrency/bounded_parallelism.md)
+    * [Bounded Parallelism](/concurrency/bounded/bounded_parallelism.md)
     * [Broadcast](/concurrency/broadcast.md)
     * [Coroutines](/concurrency/coroutine.md)
     * [Generators](/concurrency/generator.md)

concurrency/bounded/bounded_parallelism.md

@@ -1,6 +1,6 @@
 # Bounded Parallelism Pattern
 
-[Bounded parallelism](https://blog.golang.org/pipelines#TOC_9.) is similar to [parallelism](parallelism.md), but allows limits to be placed on allocation.
+[Bounded parallelism](https://blog.golang.org/pipelines#TOC_9.) is similar to [parallelism](../parallelism.md), but allows limits to be placed on allocation.
 
 # Implementation and Example
 

playground/basic/address_test.go

@@ -0,0 +1,40 @@
+package basic
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestPrintAddress(t *testing.T) {
+	var a int
+	fmt.Printf("%T, %v, %p \n", a, a, &a)
+	passByVariable(a)
+	passByPointer(&a)
+}
+
+func passByVariable(a int) {
+	fmt.Printf("%T, %v, %p \n", a, a, &a)
+}
+
+func passByPointer(a *int) {
+	fmt.Printf("%T, %v, %p \n", a, a, &a)
+	fmt.Printf("%T, %v, %p \n", *a, *a, &*a)
+}
+
+type robot struct{}
+
+func TestStructAddress(t *testing.T) {
+	var a robot
+	fmt.Printf("%T, %v, %p \n", a, a, &a)
+	passStructByVariable(a)
+	passStructByPointer(&a)
+}
+
+func passStructByVariable(a robot) {
+	fmt.Printf("[passStructByVariable] %T, %v, %p \n", a, a, &a)
+}
+
+func passStructByPointer(a *robot) {
+	fmt.Printf("[passStructByPointer] %T, %v, %p \n", a, a, &a)
+	fmt.Printf("[passStructByPointer] %T, %v, %p \n", *a, *a, &*a)
+}

playground/cbor/cbor2_test.go

@@ -0,0 +1,53 @@
+package cbor
+
+import (
+	"bytes"
+	"fmt"
+	"testing"
+
+	"github.com/2tvenom/cbor"
+)
+
+type Image struct {
+	Name    string
+	Content []byte
+}
+
+func TestCborEncode2(t *testing.T) {
+	// Read origin file
+	b := new(bytes.Buffer)
+	err := getImageBytes("./on.png", b)
+	if err != nil {
+		fmt.Println(err)
+		return
+	}
+	origin := b.Bytes()
+
+	//image := &Image{Name:"on",Content:origin}
+
+	// Encode
+	fmt.Println("--------- Encode ---------")
+
+	var buf bytes.Buffer
+	encoder := cbor.NewEncoder(&buf)
+	ok, error := encoder.Marshal(origin)
+
+	//check binary string
+	if !ok {
+		fmt.Errorf("Error decoding %s", error)
+	} else {
+		fmt.Println("Size: ", len(buf.Bytes()))
+	}
+
+	// Decode
+	//fmt.Println("--------- Decode ---------",buf.Bytes())
+	//var img []byte
+	//ok, err = encoder.Unmarshal(buf.Bytes(), &img)
+	//if !ok {
+	//	fmt.Printf("Error Unmarshal %s", err)
+	//	return
+	//}
+	////output
+	//fmt.Printf("%v", img)
+
+}

playground/cbor/cbor3_test.go

@@ -0,0 +1,48 @@
+package cbor
+
+import (
+	"bytes"
+	"fmt"
+	"testing"
+
+	"go.mozilla.org/cose"
+)
+
+func TestCborEncode3(t *testing.T) {
+	// Read origin file
+	b := new(bytes.Buffer)
+	err := getImageBytes("./on.png", b)
+	if err != nil {
+		fmt.Println(err)
+		return
+	}
+	origin := b.Bytes()
+
+	//image := &Image{Name:"on",Content:origin}
+	fmt.Println("Size: ", len(origin))
+	// Encode
+	fmt.Println("--------- Encode ---------")
+
+	encoded, error := cose.Marshal(origin)
+
+	if error != nil {
+		fmt.Errorf("Error decoding %s", error)
+	} else {
+		fmt.Println("Size: ", len(encoded))
+		//fmt.Println("Content: ",string(encoded))
+	}
+
+	// Decode
+	fmt.Println("--------- Decode ---------")
+	//var img Image
+	unmarshal, err := cose.Unmarshal(encoded)
+	if err != nil {
+		fmt.Printf("Error Unmarshal %s", err)
+		return
+	} else {
+		fmt.Println("Size: ", len(unmarshal.([]byte)))
+		//fmt.Println("Content: ",unmarshal.([]byte))
+	}
+	writeToFile("3", unmarshal.([]byte))
+
+}

playground/cbor/cbor_test.go

@@ -0,0 +1,104 @@
+package cbor
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"image"
+	"image/jpeg"
+	"image/png"
+	"log"
+	"os"
+	"testing"
+
+	"github.com/ugorji/go/codec"
+)
+
+func TestCborEncode(t *testing.T) {
+	// Read origin file
+	buf := new(bytes.Buffer)
+	err := getImageBytes("./on.png", buf)
+	if err != nil {
+		fmt.Println(err)
+		return
+	}
+	origin := buf.Bytes()
+
+	fmt.Println("size:", len(origin))
+	writeToFile("1", origin)
+
+	// Encode
+	encoded, err := encodeBinaryValue(buf.Bytes())
+	if err != nil {
+		fmt.Println(err)
+		return
+	}
+
+	fmt.Println("size:", len(encoded))
+	writeToFile("2", encoded)
+
+	// Decode
+	decoded, err := decodeBinaryValue(encoded)
+	fmt.Println("size:", len(decoded))
+	writeToFile("3", decoded)
+}
+
+func encodeBinaryValue(b []byte) ([]byte, error) {
+	var ch codec.CborHandle
+	buf := new(bytes.Buffer)
+
+	enc := codec.NewEncoder(buf, &ch)
+	err := enc.Encode(&b)
+
+	return buf.Bytes(), err
+}
+
+func decodeBinaryValue(b []byte) ([]byte, error) {
+	var ch codec.CborHandle
+	var decoded []byte
+	var bufReader = bufio.NewReader(bytes.NewReader(b))
+	var dec = codec.NewDecoder(bufReader, &ch)
+	var err = dec.Decode(&decoded)
+	return decoded, err
+}
+
+func getImageBytes(imgFile string, buf *bytes.Buffer) error {
+	// Read existing image from file
+	img, err := os.Open(imgFile)
+	if err != nil {
+		return err
+	}
+	defer img.Close()
+
+	// TODO: Attach MediaType property, determine if decoding
+	//  early is required (to optimize edge processing)
+
+	// Expect "png" or "jpeg" image type
+	imageData, imageType, err := image.Decode(img)
+	if err != nil {
+		return err
+	}
+	// Finished with file. Reset file pointer
+	img.Seek(0, 0)
+	if imageType == "jpeg" {
+		err = jpeg.Encode(buf, imageData, nil)
+		if err != nil {
+			return err
+		}
+	} else if imageType == "png" {
+		err = png.Encode(buf, imageData)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func writeToFile(fileName string, b []byte) {
+	f, _ := os.Create(fileName)
+	n2, err := f.Write(b)
+	if err != nil {
+		log.Fatal(err)
+	}
+	fmt.Printf("wrote file %d bytes\n", n2)
+}

playground/codecoverage/size.go

@@ -0,0 +1,17 @@
+package codecoverage
+
+func Size(a int) string {
+	switch {
+	case a < 0:
+		return "negative"
+	case a == 0:
+		return "zero"
+	case a < 10:
+		return "small"
+	case a < 100:
+		return "big"
+	case a < 1000:
+		return "huge"
+	}
+	return "enormous"
+}

playground/codecoverage/size_test.go

@@ -0,0 +1,26 @@
+package codecoverage
+
+import "testing"
+
+type Test struct {
+	in  int
+	out string
+}
+
+var tests = []Test{
+	{-1, "negative"},
+	{0, "zero"},
+	{5, "small"},
+	{99, "big"},
+	{100, "huge"},
+	{10001, "enormous"},
+}
+
+func TestSize(t *testing.T) {
+	for i, test := range tests {
+		size := Size(test.in)
+		if size != test.out {
+			t.Errorf("#%d: Size(%d)=%s; want %s", i, test.in, size, test.out)
+		}
+	}
+}

playground/cron/cron_test.go

@@ -0,0 +1,86 @@
+package cron
+
+import (
+	"fmt"
+	"testing"
+	"time"
+
+	"github.com/edgexfoundry/edgex-go/pkg/models"
+	"github.com/robfig/cron"
+)
+
+type Job struct {
+	schedule       models.Schedule
+	scheduleEvents []models.ScheduleEvent
+}
+
+func (job Job) Run() {
+	fmt.Println(job.schedule.Name, job.schedule.Frequency)
+}
+
+func TestCronWithAddJob(t *testing.T) {
+	var job = Job{
+		schedule: models.Schedule{
+			Id:        "xxx",
+			Name:      "5sec-schedule",
+			Frequency: "PT5S",
+		},
+		scheduleEvents: []models.ScheduleEvent{},
+	}
+	var job2 = Job{
+		schedule: models.Schedule{
+			Id:        "xxx",
+			Name:      "2sec-schedule",
+			Frequency: "PT2S",
+		},
+		scheduleEvents: []models.ScheduleEvent{},
+	}
+
+	// init cron
+	c := cron.New()
+
+	// add cron job
+	var spec = fmt.Sprintf("@every %v", ParseDuration(job.schedule.Frequency))
+	c.AddJob(spec, job)
+
+	spec = fmt.Sprintf("@every %v", ParseDuration(job2.schedule.Frequency))
+	c.AddJob(spec, job2)
+
+	// start cron
+	c.Start()
+
+	time.Sleep(10 * time.Second)
+	// keep alive
+	//select {}
+}
+
+func TestCronWithAddFunc(t *testing.T) {
+	// init cron
+	c := cron.New()
+
+	// add cron job
+	var duration = ParseDuration("PT2S")
+	var spec = fmt.Sprintf("@every %v", duration)
+
+	c.AddFunc(spec, func() {
+		// @every 2s
+		fmt.Println(spec)
+	})
+
+	// start cron
+	c.Start()
+
+	// keep alive
+	select {}
+}
+
+func TestParseISO8601(t *testing.T) {
+	var duration = ParseDuration("PT2S")
+
+	// PT2S -> 2s
+	fmt.Println(duration)
+	// PT15M -> 15m0s
+	fmt.Println(ParseDuration("PT15M"))
+	// P12Y4MT15M -> 108000h15m0s
+	fmt.Println(ParseDuration("P12Y4MT15M"))
+}

playground/cron/iso8601parser.go

@@ -0,0 +1,35 @@
+package cron
+
+import (
+	"regexp"
+	"strconv"
+	"time"
+)
+
+func ParseDuration(str string) time.Duration {
+	durationRegex := regexp.MustCompile(`P(?P<years>\d+Y)?(?P<months>\d+M)?(?P<days>\d+D)?T?(?P<hours>\d+H)?(?P<minutes>\d+M)?(?P<seconds>\d+S)?`)
+	matches := durationRegex.FindStringSubmatch(str)
+
+	years := ParseInt64(matches[1])
+	months := ParseInt64(matches[2])
+	days := ParseInt64(matches[3])
+	hours := ParseInt64(matches[4])
+	minutes := ParseInt64(matches[5])
+	seconds := ParseInt64(matches[6])
+
+	hour := int64(time.Hour)
+	minute := int64(time.Minute)
+	second := int64(time.Second)
+	return time.Duration(years*24*365*hour + months*30*24*hour + days*24*hour + hours*hour + minutes*minute + seconds*second)
+}
+
+func ParseInt64(value string) int64 {
+	if len(value) == 0 {
+		return 0
+	}
+	parsed, err := strconv.Atoi(value[:len(value)-1])
+	if err != nil {
+		return 0
+	}
+	return int64(parsed)
+}

playground/factory/robot.go

@@ -0,0 +1,14 @@
+package factory
+
+import "log"
+
+var speakFuncs = make(map[string]interface{})
+
+func say(funcName string) {
+	speakFunc, ok := speakFuncs[funcName]
+	if !ok {
+		log.Println("speakFunc not exist")
+	} else {
+		speakFunc.(func())()
+	}
+}

playground/factory/robot_test.go

@@ -0,0 +1,8 @@
+package factory
+
+import "testing"
+
+func TestSay(t *testing.T) {
+	say("xxx")
+	say("hi")
+}

playground/factory/robotfuncs.go

@@ -0,0 +1,16 @@
+package factory
+
+import "log"
+
+func sayHi() {
+	log.Print("Hi~")
+}
+
+func sayHello() {
+	log.Print("Hello~")
+}
+
+func init() {
+	speakFuncs["hi"] = sayHi
+	speakFuncs["hello"] = sayHello
+}

playground/goroutine/basic_chan_test.go

@@ -0,0 +1,24 @@
+package goroutine
+
+import (
+	"fmt"
+	"testing"
+	"time"
+)
+
+func TestFiveGopherWithChan(t *testing.T) {
+	c := make(chan int)
+	for i := 0; i < 5; i++ {
+		go sleepyGopherWithChan(i, c)
+	}
+	for i := 0; i < 5; i++ {
+		gopherID := <-c
+		fmt.Println("gopher ", gopherID, " has finished sleeping")
+	}
+}
+
+func sleepyGopherWithChan(id int, c chan int) {
+	time.Sleep(2 * time.Second)
+	fmt.Println("... ", id, " snore ...")
+	c <- id
+}

playground/goroutine/basic_test.go

@@ -0,0 +1,25 @@
+package goroutine
+
+import (
+	"fmt"
+	"testing"
+	"time"
+)
+
+func TestOneGopher(t *testing.T) {
+	go sleepyGopher(1)
+	time.Sleep(3 * time.Second)
+}
+
+func TestFiveGopher(t *testing.T) {
+	c := make(chan int)
+	for i := 0; i < 5; i++ {
+		go sleepyGopherWithChan(i, c)
+	}
+	time.Sleep(3 * time.Second)
+}
+
+func sleepyGopher(id int) {
+	time.Sleep(2 * time.Second)
+	fmt.Println("... ", id, " snore ...")
+}

playground/goroutine/basic_waitgroup_test.go

@@ -0,0 +1,32 @@
+package goroutine
+
+import (
+	"fmt"
+	"sync"
+	"testing"
+	"time"
+)
+
+func TestWaitGophers(t *testing.T) {
+	var gophers = []string{"tom", "peter", "john", "brown"}
+
+	var waitGroup sync.WaitGroup
+	waitGroup.Add(len(gophers))
+
+	for i := 0; i < len(gophers); i++ {
+		go func(wg *sync.WaitGroup, name string) {
+			sleepyGopherSnore(name)
+			wg.Done()
+		}(&waitGroup, gophers[i])
+	}
+
+	waitGroup.Wait()
+
+	fmt.Println("All done")
+}
+
+func sleepyGopherSnore(name string) {
+	fmt.Println(name, ": ... start snore")
+	time.Sleep(2 * time.Second)
+	fmt.Println(name, ": ... snore")
+}

playground/goroutine/deadlock_test.go

@@ -0,0 +1,11 @@
+package goroutine
+
+import "testing"
+
+// A deadlock happens when a group of goroutines are waiting for each other and none of them is able to proceed.
+// The program will get stuck on the channel send operation waiting forever for someone to read the value.
+// Go is able to detect situations like this at runtime.
+func TestDeadlock(t *testing.T) {
+	c := make(chan int)
+	<-c
+}

playground/goroutine/pipeline_test.go

@@ -0,0 +1,39 @@
+package goroutine
+
+import (
+	"fmt"
+	"strings"
+	"testing"
+)
+
+func sourceGopher(downstream chan string) {
+	for _, v := range []string{"hello world", "a bad apple", "goodbye all"} {
+		downstream <- v
+	}
+	close(downstream)
+}
+
+func filterGopher(upstream, downstream chan string) {
+	for item := range upstream {
+		fmt.Println("filter ", item)
+
+		if !strings.Contains(item, "bad") {
+			downstream <- item
+		}
+	}
+}
+
+func printGopher(upstream chan string) {
+	for item := range upstream {
+		fmt.Println("print ", item)
+	}
+}
+
+// Pipeline source->filter->print
+func TestPipeline(t *testing.T) {
+	c0 := make(chan string)
+	c1 := make(chan string)
+	go sourceGopher(c0)
+	go filterGopher(c0, c1)
+	printGopher(c1)
+}

playground/http/get_test.go

@@ -0,0 +1,48 @@
+package http
+
+import (
+	"fmt"
+	"io/ioutil"
+	"log"
+	"math/rand"
+	"net/http"
+	"sync"
+	"testing"
+	"time"
+)
+
+func TestGet(t *testing.T) {
+	counts := 2
+
+	var wg sync.WaitGroup
+	wg.Add(counts)
+
+	for i := 0; i < counts; i++ {
+		go func() {
+			defer wg.Done()
+			getValue()
+		}()
+	}
+	wg.Wait()
+}
+
+func getValue() {
+	rand.Seed(time.Now().UnixNano())
+	x := rand.Intn(10)
+	var url string
+	if x > 5 {
+		url = "http://localhost:48082/api/v1/device/5bae2ef4f37ba14693a5e4fc/command/5bae2ef4f37ba14693a5e4eb"
+	} else {
+		url = "http://localhost:48082/api/v1/device/5bae2d1bf37ba14693a5e4e9/command/5bae2d05f37ba14693a5e4e2"
+	}
+	resp, err := http.Get(url)
+	if err != nil {
+		fmt.Println(err)
+	}
+
+	resBody, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		log.Fatal(err)
+	}
+	fmt.Println(string(resBody))
+}

playground/http/postyamlstring_test.go

@@ -0,0 +1,46 @@
+package http
+
+import (
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"testing"
+)
+
+func TestPostYamlString(t *testing.T) {
+	var filePath = "/Users/bruce/Desktop/HVAC-CoolMasterNet.yml"
+	var url = "http://localhost:48081/api/v1/deviceprofile/upload"
+
+	// read file to byte
+	yamlFile, err := ioutil.ReadFile(filePath)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	fmt.Println(string(yamlFile))
+
+	// create http post request
+	req, err := http.NewRequest(http.MethodPost, url, bytes.NewReader(yamlFile))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// submit request
+	client := &http.Client{}
+	res, err := client.Do(req)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// check response
+	fmt.Println("== upload finish ==")
+	resBody, err := ioutil.ReadAll(res.Body)
+	if err != nil {
+		t.Fatal(err)
+	}
+	fmt.Println(res.StatusCode)
+	fmt.Println(res.Header)
+	res.Body.Close()
+	fmt.Println(string(resBody))
+}

playground/http/upload_test.go

@@ -0,0 +1,63 @@
+package http
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"mime/multipart"
+	"net/http"
+	"path/filepath"
+	"testing"
+)
+
+func TestUploadFormFile(t *testing.T) {
+	var filePath = "/Users/bruce/Desktop/HVAC-CoolMasterNet.yml"
+	var url = "http://localhost:48081/api/v1/deviceprofile/uploadfile"
+
+	// Retch file
+	fmt.Println("Read file: ", filepath.Base(filePath))
+	yamlFile, err := ioutil.ReadFile(filePath)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// create form data
+	body := new(bytes.Buffer)
+	//body := &bytes.Buffer{}
+	writer := multipart.NewWriter(body)
+	formFileWriter, err := writer.CreateFormFile("file", filepath.Base(filePath))
+	if err != nil {
+		t.Fatal(err)
+	}
+	_, err = io.Copy(formFileWriter, bytes.NewReader(yamlFile))
+	if err != nil {
+		t.Fatal(err)
+	}
+	writer.Close()
+
+	// create http post request
+	req, err := http.NewRequest(http.MethodPost, url, body)
+	if err != nil {
+		t.Fatal(err)
+	}
+	req.Header.Add("Content-Type", writer.FormDataContentType())
+
+	// submit request
+	client := &http.Client{}
+	res, err := client.Do(req)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// check response
+	fmt.Println("== upload finish ==")
+	resBody, err := ioutil.ReadAll(res.Body)
+	if err != nil {
+		t.Fatal(err)
+	}
+	fmt.Println(res.StatusCode)
+	fmt.Println(res.Header)
+	res.Body.Close()
+	fmt.Println(string(resBody))
+}

playground/mocklib/mocks/Robot.go

@@ -0,0 +1,15 @@
+// Code generated by mockery v1.0.0. DO NOT EDIT.
+
+package mocks
+
+import mock "github.com/stretchr/testify/mock"
+
+// Robot is an autogenerated mock type for the Robot type
+type Robot struct {
+	mock.Mock
+}
+
+// SayHi provides a mock function with given fields:
+func (_m *Robot) SayHi() {
+	_m.Called()
+}

playground/mocklib/robot.go

@@ -0,0 +1,45 @@
+package mocklib
+
+import "fmt"
+
+// Robot
+type Robot interface {
+	SayHi()
+}
+
+// ServiceRobot is kind of Robot can offer services
+type ServiceRobot struct {
+}
+
+func (robot *ServiceRobot) SayHi() {
+	fmt.Println("Hi, I'm service robot")
+}
+
+// IndustrialRobot is kind of Robot can do some jobs
+type IndustrialRobot struct {
+}
+
+func (robot *IndustrialRobot) SayHi() {
+	fmt.Println("Hi, I'm industrial robot")
+}
+
+func StartRobots() {
+	robots := initializeRobots()
+	makeRobotsSayHi(robots)
+}
+
+// initialize all robots
+func initializeRobots() []Robot {
+	robots := []Robot{
+		&ServiceRobot{},
+		&IndustrialRobot{},
+	}
+	return robots
+}
+
+// makeRobotsSayHi is used for making robots say hi
+func makeRobotsSayHi(robots []Robot) {
+	for _, robot := range robots {
+		robot.SayHi()
+	}
+}

playground/mocklib/robot_test.go

@@ -0,0 +1,32 @@
+package mocklib
+
+import (
+	"github.com/weichou1229/go-patterns/playground/mocklib/mocks"
+	"testing"
+)
+
+func TestStartRobots(t *testing.T) {
+	StartRobots()
+}
+
+func TestMakeRobotsSayHi(t *testing.T) {
+	// create an instance of our test object
+	mockRobotA := new(mocks.Robot)
+	mockRobotB := new(mocks.Robot)
+
+	// setup expectations
+	mockRobotA.On("SayHi").Return(nil, nil)
+	mockRobotB.On("SayHi").Return(nil, nil)
+
+	robots := []Robot{
+		mockRobotA,
+		mockRobotB,
+	}
+
+	// Act
+	makeRobotsSayHi(robots)
+
+	// Assert that the expectations were met
+	mockRobotA.AssertExpectations(t)
+	mockRobotB.AssertExpectations(t)
+}

playground/panic/trypanic.go

@@ -0,0 +1,10 @@
+package trypanic
+
+import (
+	"fmt"
+)
+
+func Try() {
+	var test *string
+	fmt.Println(*test)
+}

playground/parse/parseInt_test.go

@@ -0,0 +1,14 @@
+package parse
+
+import (
+	"fmt"
+	"strconv"
+	"testing"
+)
+
+func TestParseInt(t *testing.T) {
+	var _, err = strconv.ParseInt("127", 0, 8)
+	if err != nil {
+		fmt.Println(err)
+	}
+}

playground/pointer/pointer_test.go

@@ -0,0 +1,26 @@
+package pointer
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestBasic(t *testing.T) {
+	answer := 42
+	fmt.Println(&answer) // & is address operator
+
+	address := &answer
+	fmt.Println(*address)                     // * is dereferencing, which providers the value that a memory address refers to.
+	fmt.Printf("address is a %T \n", address) // print the pointer type
+
+	var address2 *int  // declare a pointer
+	address2 = address // address2 can store some pinter type
+	fmt.Println(*address2)
+
+}
+
+func TestPointer(t *testing.T) {
+	var test *string = new(string)
+	*test = "123"
+	fmt.Println(test)
+}

playground/singleton/internal/singleton.go

@@ -0,0 +1,27 @@
+package internal
+
+import (
+	"fmt"
+	"sync"
+)
+
+// singleton is private struct, it should be created and fetched by GetSingletonObject func
+type singleton struct {
+}
+
+func (singleton) SayHi() {
+	fmt.Println("Hi!")
+}
+
+var (
+	once     sync.Once
+	instance singleton
+)
+
+func GetSingletonObject() singleton {
+	once.Do(func() {
+		instance = singleton{}
+	})
+
+	return instance
+}

playground/singleton/main.go

@@ -0,0 +1,10 @@
+package main
+
+import (
+	"github.com/weichou1229/go-patterns/playground/singleton/internal"
+)
+
+func main() {
+	var s = internal.GetSingletonObject()
+	s.SayHi()
+}

playground/syncmap/syncmap_test.go

@@ -0,0 +1,52 @@
+package syncmap
+
+import (
+	"fmt"
+	"sync"
+	"testing"
+)
+
+type Order struct {
+	Id int
+}
+
+func TestSync(t *testing.T) {
+	var waitGroup sync.WaitGroup
+	waitGroup.Add(10)
+	var cache sync.Map
+
+	for i := 0; i < 10; i++ {
+		go func() {
+			cache.Store("test", &Order{})
+			order, _ := cache.Load("test")
+			o := order.(*Order)
+			fmt.Println(o)
+			waitGroup.Done()
+		}()
+	}
+	waitGroup.Wait()
+}
+
+func TestSync2(t *testing.T) {
+	var cache sync.Map
+
+	cache.Store("test", nil)
+
+	if order, ok := cache.Load("test"); ok && order != nil {
+		fmt.Println(order)
+	} else {
+		fmt.Println("not exist")
+	}
+}
+
+func TestSync3(t *testing.T) {
+	var cache sync.Map
+	orders := make([]Order, 2)
+
+	cache.Store("test2", orders[0])
+	cache.Store("test", orders[0])
+
+	order, ok := cache.Load("test")
+	fmt.Println(ok, order)
+
+}

playground/xml/xml_test.go

@@ -0,0 +1,63 @@
+package xml
+
+import (
+	"fmt"
+	xj "github.com/basgys/goxml2json"
+	"github.com/buger/jsonparser"
+	"os"
+	"testing"
+)
+
+type Person struct {
+	Name string `xml:"name"`
+}
+
+func TestParse(t *testing.T) {
+	xmlFile, err := os.Open("2018Q1.xml")
+	if err != nil {
+		fmt.Println(err)
+		return
+	}
+	defer xmlFile.Close()
+	json, err := xj.Convert(xmlFile)
+	if err != nil {
+		fmt.Println(err)
+		return
+	}
+
+	fmt.Println(json.String())
+
+	//err = jsonparser.ObjectEach(json.Bytes(), objectEach,"xbrl")
+	//if err != nil {
+	//	fmt.Println(err)
+	//	return
+	//}
+
+	// 營業收入
+	var revenue string
+	_, err = jsonparser.ArrayEach(json.Bytes(), func(value []byte, dataType jsonparser.ValueType, offset int, err error) {
+		revenue, err = jsonparser.GetString(value, "#content")
+		fmt.Println(revenue)
+	}, "xbrl", "Revenue")
+	if err != nil {
+		fmt.Println(err)
+		return
+	}
+}
+
+func parse(b []byte) {
+	err := jsonparser.ObjectEach(b, objectEach, "xbrl")
+	if err != nil {
+		fmt.Println(err)
+		return
+	}
+}
+
+func objectEach(key []byte, value []byte, dataType jsonparser.ValueType, offset int) error {
+	fmt.Printf("[Key]: [%s]\n Value: '%s'\n Type: %s\n", string(key), string(value), dataType)
+	return nil
+}
+
+func arrayEach(value []byte, dataType jsonparser.ValueType, offset int, err error) {
+	fmt.Printf("Array Value: '%s'\n Type: %s\n", string(value), dataType)
+}