Better example verification (#108)

Makefile

@@ -21,7 +21,7 @@ test_reconnect:
 
 validate_examples:
 	go run dev/update-examples-deps/main.go
-	bash dev/validate_examples.sh
+	go run dev/validate-examples/main.go
 
 
 fmt:

_examples/cqrs-protobuf/.validate_example.yml

@@ -0,0 +1,4 @@
+validation_cmd: "docker-compose up"
+teardown_cmd: "docker-compose down"
+timeout: 30
+expected_output: "beers ordered to room 3"

_examples/http-to-kafka/.validate_example.yml

@@ -0,0 +1,4 @@
+validation_cmd: "docker-compose up"
+teardown_cmd: "docker-compose down"
+timeout: 30
+expected_output: "Starting handler"

_examples/kafka-to-http/.validate_example.yml

@@ -0,0 +1,4 @@
+validation_cmd: "docker-compose up"
+teardown_cmd: "docker-compose down"
+timeout: 60
+expected_output: "POST /foo_or_bar: message"

_examples/metrics/.validate_example.yml

@@ -0,0 +1,4 @@
+validation_cmd: "docker-compose up"
+teardown_cmd: "docker-compose down"
+timeout: 60
+expected_output: "msg=\"Message acked\""

_examples/simple-app/.validate_example_publishing.yml

@@ -0,0 +1,4 @@
+validation_cmd: "docker-compose up"
+teardown_cmd: "docker-compose down"
+timeout: 60
+expected_output: "msg=\"Message sent to Kafka\""

_examples/simple-app/.validate_example_subscribing.yml

@@ -0,0 +1,4 @@
+validation_cmd: "docker-compose up"
+teardown_cmd: "docker-compose down"
+timeout: 60
+expected_output: "msg=\"Starting handler\""

_examples/your-first-app/.validate_example.yml

@@ -0,0 +1,4 @@
+validation_cmd: "docker-compose up"
+teardown_cmd: "docker-compose down"
+timeout: 60
+expected_output: "received event [0-9]+"

dev/validate-examples/go.mod

@@ -0,0 +1,5 @@
+module github.com/ThreeDotsLabs/watermill/dev/validate-examples
+
+go 1.12
+
+require gopkg.in/yaml.v2 v2.2.2 // indirect

dev/validate-examples/go.sum

@@ -0,0 +1,3 @@
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v2 v2.2.2 h1:ZCJp+EgiOT7lHqUV2J862kp8Qj64Jo6az82+3Td9dZw=
+gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=

dev/validate-examples/main.go

@@ -0,0 +1,122 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"regexp"
+	"strings"
+	"time"
+
+	yaml "gopkg.in/yaml.v2"
+)
+
+type Config struct {
+	ValidationCmd  string `yaml:"validation_cmd"`
+	TeardownCmd    string `yaml:"teardown_cmd"`
+	Timeout        int    `yaml:"timeout"`
+	ExpectedOutput string `yaml:"expected_output"`
+}
+
+func (c *Config) LoadFrom(path string) error {
+	file, err := ioutil.ReadFile(path)
+	if err != nil {
+		return err
+	}
+	err = yaml.Unmarshal(file, c)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+func main() {
+	walkErr := filepath.Walk(".", func(exampleConfig string, f os.FileInfo, _ error) error {
+		matches, _ := filepath.Match(".validate_example*.yml", f.Name())
+		if !matches {
+			return nil
+		}
+
+		exampleDirectory := filepath.Dir(exampleConfig)
+		ok, err := validate(exampleConfig)
+
+		if err != nil {
+			fmt.Printf("validation for %s failed, err: %v\n", exampleDirectory, err)
+			return nil
+		}
+
+		if ok {
+			fmt.Printf("validation for %s succeeded\n", exampleDirectory)
+			return nil
+		}
+
+		fmt.Printf("validation for %s failed\n", exampleDirectory)
+		return nil
+	})
+	if walkErr != nil {
+		panic(walkErr)
+	}
+
+}
+
+func validate(path string) (bool, error) {
+	config := &Config{}
+	err := config.LoadFrom(path)
+	if err != nil {
+		return false, fmt.Errorf("could not load config, err: %v", err)
+	}
+
+	cmdAndArgs := strings.Fields(config.ValidationCmd)
+	validationCmd := exec.Command(cmdAndArgs[0], cmdAndArgs[1:]...)
+	validationCmd.Dir = filepath.Dir(path)
+	defer func() {
+		if config.TeardownCmd == "" {
+			return
+		}
+		cmdAndArgs := strings.Fields(config.TeardownCmd)
+		teardownCmd := exec.Command(cmdAndArgs[0], cmdAndArgs[1:]...)
+		teardownCmd.Dir = filepath.Dir(path)
+		_ = teardownCmd.Run()
+	}()
+
+	stdout, err := validationCmd.StdoutPipe()
+	if err != nil {
+		return false, fmt.Errorf("could not attach to stdout, err: %v", err)
+	}
+
+	err = validationCmd.Start()
+	if err != nil {
+		return false, fmt.Errorf("could not start validation, err: %v", err)
+	}
+
+	success := make(chan bool)
+
+	go func() {
+		output := bufio.NewReader(stdout)
+		for {
+			line, _, err := output.ReadLine()
+			if err != nil {
+				if err == io.EOF {
+					break
+				}
+			}
+			ok, _ := regexp.Match(config.ExpectedOutput, line)
+			if ok {
+				success <- true
+				return
+			}
+		}
+		success <- false
+	}()
+
+	select {
+	case success := <-success:
+		return success, nil
+	case <-time.After(time.Duration(config.Timeout) * time.Second):
+		return false, fmt.Errorf("validation command timed out")
+	}
+}

docs/content/docs/getting-started/amqp/.validate_example.yml

@@ -0,0 +1,4 @@
+validation_cmd: "docker-compose up"
+teardown_cmd: "docker-compose down"
+timeout: 30
+expected_output: "received message: [0-9a-f\\-]+, payload: Hello, world!"

docs/content/docs/getting-started/go-channel/.validate_example.yml

@@ -0,0 +1,3 @@
+validation_cmd: "docker-compose up"
+timeout: 1
+expected_output: "payload: Hello, world!"