Feature: diff/sync commands - read from stdin - resolves #8

cmd/diff.go

@@ -56,7 +56,8 @@ that will be created or updated or deleted.
 func init() {
 	rootCmd.AddCommand(diffCmd)
 	diffCmd.Flags().StringVarP(&diffCmdKongStateFile,
-		"state", "s", "kong.yaml", "file containing Kong's configuration.")
+		"state", "s", "kong.yaml", "file containing Kong's configuration. "+
+			"Use '-' to read from stdin.")
 	diffCmd.Flags().BoolVar(&dumpConfig.SkipConsumers, "skip-consumers",
 		false, "do not diff consumers or "+
 			"any plugins associated with consumers")

cmd/sync.go

@@ -53,7 +53,8 @@ to get Kong's state in sync with the input state.`,
 func init() {
 	rootCmd.AddCommand(syncCmd)
 	syncCmd.Flags().StringVarP(&syncCmdKongStateFile,
-		"state", "s", "kong.yaml", "file containing Kong's configuration.")
+		"state", "s", "kong.yaml", "file containing Kong's configuration. "+
+			"Use '-' to read from stdin.")
 	syncCmd.Flags().BoolVar(&dumpConfig.SkipConsumers, "skip-consumers",
 		false, "do not diff consumers or "+
 			"any plugins associated with consumers")

file/reader.go

@@ -3,6 +3,7 @@ package file
 import (
 	"fmt"
 	"io/ioutil"
+	"os"
 	"strconv"
 
 	"github.com/hbagdi/deck/counter"
@@ -223,7 +224,13 @@ func GetStateFromFile(filename string) (*state.KongState, error) {
 func readFile(kongStateFile string) (*fileStructure, error) {
 
 	var s fileStructure
-	b, err := ioutil.ReadFile(kongStateFile)
+	var b []byte
+	var err error
+	if kongStateFile == "-" {
+		b, err = ioutil.ReadAll(os.Stdin)
+	} else {
+		b, err = ioutil.ReadFile(kongStateFile)
+	}
 	if err != nil {
 		return nil, err
 	}

file/reader_test.go

@@ -1,8 +1,13 @@
 package file
 
 import (
+	"bytes"
+	"io/ioutil"
+	"os"
 	"reflect"
 	"testing"
+
+	"github.com/stretchr/testify/assert"
 )
 
 func Test_ensureJSON(t *testing.T) {
@@ -32,3 +37,76 @@ func Test_ensureJSON(t *testing.T) {
 		})
 	}
 }
+
+func TestReadKongStateFromStdinFailsToParseText(t *testing.T) {
+	var filename = "-"
+	assert := assert.New(t)
+	assert.Equal("-", filename)
+
+	var content bytes.Buffer
+	content.Write([]byte("hunter2\n"))
+
+	tmpfile, err := ioutil.TempFile("", "example")
+	if err != nil {
+		panic(err)
+	}
+	defer os.Remove(tmpfile.Name())
+
+	if _, err := tmpfile.Write(content.Bytes()); err != nil {
+		panic(err)
+	}
+
+	if _, err := tmpfile.Seek(0, 0); err != nil {
+		panic(err)
+	}
+
+	oldStdin := os.Stdin
+	defer func() { os.Stdin = oldStdin }() // Restore original Stdin
+
+	os.Stdin = tmpfile
+
+	ks, err := GetStateFromFile(filename)
+	assert.NotNil(err)
+	assert.Empty(ks)
+}
+
+func TestReadKongStateFromStdin(t *testing.T) {
+	var filename = "-"
+	assert := assert.New(t)
+	assert.Equal("-", filename)
+
+	var content bytes.Buffer
+	content.Write([]byte("services:\n- host: test.com\n  name: test service\n"))
+
+	tmpfile, err := ioutil.TempFile("", "example")
+	if err != nil {
+		panic(err)
+	}
+	defer os.Remove(tmpfile.Name())
+
+	if _, err := tmpfile.Write(content.Bytes()); err != nil {
+		panic(err)
+	}
+
+	if _, err := tmpfile.Seek(0, 0); err != nil {
+		panic(err)
+	}
+
+	oldStdin := os.Stdin
+	defer func() { os.Stdin = oldStdin }() // Restore original Stdin
+
+	os.Stdin = tmpfile
+
+	ks, err := GetStateFromFile(filename)
+	assert.NotNil(ks)
+	assert.Nil(err)
+
+	services, err := ks.Services.GetAll()
+	if err != nil {
+		panic(err)
+	}
+	assert.Equal("test.com", *services[0].Host)
+	assert.NotEqual("not.the.same.as.test.com", *services[0].Host)
+	assert.Equal("test service", *services[0].Name)
+	assert.NotEqual("not the same as 'test service'", *services[0].Name)
+}

file/writer.go

@@ -1,6 +1,7 @@
 package file
 
 import (
+	"fmt"
 	"io/ioutil"
 	"sort"
 	"strings"
@@ -165,7 +166,11 @@ func KongStateToFile(kongState *state.KongState, filename string) error {
 	})
 
 	c, err := yaml.Marshal(file)
-	err = ioutil.WriteFile(filename, c, 0600)
+	if filename == "-" {
+		_, err = fmt.Print(string(c))
+	} else {
+		err = ioutil.WriteFile(filename, c, 0600)
+	}
 	if err != nil {
 		return err
 	}

file/writer_test.go

@@ -0,0 +1,112 @@
+package file
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"log"
+	"os"
+	"sync"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
+	"github.com/hbagdi/deck/state"
+	"github.com/hbagdi/go-kong/kong"
+)
+
+func captureOutput(f func()) string {
+	reader, writer, err := os.Pipe()
+	if err != nil {
+		panic(err)
+	}
+	stdout := os.Stdout
+	stderr := os.Stderr
+	defer func() {
+		os.Stdout = stdout
+		os.Stderr = stderr
+		log.SetOutput(os.Stderr)
+	}()
+	os.Stdout = writer
+	os.Stderr = writer
+
+	log.SetOutput(writer)
+	out := make(chan string)
+	wg := new(sync.WaitGroup)
+	wg.Add(1)
+	go func() {
+		var buf bytes.Buffer
+		wg.Done()
+		io.Copy(&buf, reader)
+		out <- buf.String()
+	}()
+	wg.Wait()
+	f()
+	writer.Close()
+	return <-out
+}
+func TestWriteKongStateToStdoutEmptyState(t *testing.T) {
+	var ks, _ = state.NewKongState()
+	var filename = "-"
+	assert := assert.New(t)
+	assert.Equal("-", filename)
+	assert.NotEmpty(t, ks)
+	output := captureOutput(func() {
+		KongStateToFile(ks, filename)
+	})
+	assert.Equal("{}\n", output)
+
+}
+func TestWriteKongStateToStdoutStateWithOneService(t *testing.T) {
+	var ks, _ = state.NewKongState()
+	var filename = "-"
+	assert := assert.New(t)
+	var service state.Service
+	service.ID = kong.String("first")
+	service.Host = kong.String("example.com")
+	service.Name = kong.String("my-service")
+	ks.Services.Add(service)
+	output := captureOutput(func() {
+		KongStateToFile(ks, filename)
+	})
+	fmt.Print(service.Host)
+	expected := fmt.Sprintf("services:\n- host: %s\n  name: %s\n", *service.Host, *service.Name)
+	assert.Equal(expected, output)
+
+}
+func TestWriteKongStateToStdoutStateWithOneServiceOneRoute(t *testing.T) {
+	var ks, _ = state.NewKongState()
+	var filename = "-"
+	assert := assert.New(t)
+	var service state.Service
+	service.ID = kong.String("first")
+	service.Host = kong.String("example.com")
+	service.Name = kong.String("my-service")
+	ks.Services.Add(service)
+
+	var route state.Route
+	route.Name = kong.String("my-route")
+	route.ID = kong.String("first")
+	route.Hosts = kong.StringSlice("example.com", "demo.example.com")
+	route.Service = &kong.Service{
+		ID:   kong.String(*service.ID),
+		Name: kong.String(*service.Name),
+	}
+
+	ks.Routes.Add(route)
+
+	output := captureOutput(func() {
+		KongStateToFile(ks, filename)
+	})
+	fmt.Print(service.Host)
+	expected := fmt.Sprintf(`services:
+- host: %s
+  name: %s
+  routes:
+  - hosts:
+    - %s
+    - %s
+    name: %s
+`, *service.Host, *service.Name, *route.Hosts[0], *route.Hosts[1], *route.Name)
+	assert.Equal(expected, output)
+}

go.mod

@@ -28,7 +28,8 @@ require (
 	github.com/yudai/gojsondiff v1.0.0
 	github.com/yudai/golcs v0.0.0-20170316035057-ecda9a501e82 // indirect
 	github.com/yudai/pp v2.0.1+incompatible // indirect
-	golang.org/x/sys v0.0.0-20181128092732-4ed8d59d0b35 // indirect
+	golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3 // indirect
+	golang.org/x/sys v0.0.0-20190405154228-4b34438f7a67 // indirect
 	gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127 // indirect
 	gopkg.in/yaml.v2 v2.2.2
 )

go.sum

@@ -86,15 +86,19 @@ github.com/yudai/golcs v0.0.0-20170316035057-ecda9a501e82 h1:BHyfKlQyqbsFN5p3Ifn
 github.com/yudai/golcs v0.0.0-20170316035057-ecda9a501e82/go.mod h1:lgjkn3NuSvDfVJdfcVVdX+jpBxNmX4rDAzaS45IcYoM=
 github.com/yudai/pp v2.0.1+incompatible h1:Q4//iY4pNF6yPLZIigmvcl7k/bPgrcTPIFIcmawg5bI=
 github.com/yudai/pp v2.0.1+incompatible/go.mod h1:PuxR/8QJ7cyCkFp/aUDS+JY727OFEZkTdatxwunjIkc=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/net v0.0.0-20180906233101-161cd47e91fd h1:nTDtHvHSdCn1m6ITfMRqtOd/9+7a3s8RBNOZ3eYZzJA=
 golang.org/x/net v0.0.0-20180906233101-161cd47e91fd/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
+golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3 h1:0GoQqolDA55aaLxZyTzK/Y2ePZzZTUrRacwib7cNsYQ=
+golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/sync v0.0.0-20180314180146-1d60e4601c6f h1:wMNYb4v58l5UBM7MYRLPG6ZhfOqbKu7X5eyFl8ZhKvA=
 golang.org/x/sync v0.0.0-20180314180146-1d60e4601c6f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20180906133057-8cf3aee42992 h1:BH3eQWeGbwRU2+wxxuuPOdFBmaiBH81O8BugSjHeTFg=
 golang.org/x/sys v0.0.0-20180906133057-8cf3aee42992/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20180909124046-d0be0721c37e/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
-golang.org/x/sys v0.0.0-20181128092732-4ed8d59d0b35 h1:YAFjXN64LMvktoUZH9zgY4lGc/msGN7HQfoSuKCgaDU=
-golang.org/x/sys v0.0.0-20181128092732-4ed8d59d0b35/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20190405154228-4b34438f7a67 h1:1Fzlr8kkDLQwqMP8GxrhptBLqZG/EDpiATneiZHY998=
+golang.org/x/sys v0.0.0-20190405154228-4b34438f7a67/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.3.0 h1:g61tztE5qeGQ89tm6NTjjM9VPIm088od1l6aSorWRWg=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=