Merge pull request #9 from linyows/support-downgrade

Support downgrade of APP version

dewy.go

@@ -106,18 +106,17 @@ func (d *Dewy) Run() error {
 		return err
 	}
 
-	if !d.repo.IsDownloadNecessary() {
-		log.Print("[DEBUG] Download skipped")
-		return nil
-	}
-
-	key, err := d.repo.Download()
+	key, err := d.repo.GetDeploySourceKey()
 	if err != nil {
-		log.Printf("[DEBUG] Download failure: %#v", err)
+		if err.Error() == "No need to deploy" {
+			log.Print("[DEBUG] Deploy skipped")
+		} else {
+			log.Printf("[DEBUG] Download failure: %#v", err)
+		}
 		return nil
 	}
 
-	d.notice.Notify(ctx, fmt.Sprintf("New release <%s|%s> was downloaded",
+	d.notice.Notify(ctx, fmt.Sprintf("New shipping <%s|%s> was detected",
 		d.repo.ReleaseURL(), d.repo.ReleaseTag()))
 
 	if err := d.deploy(key); err != nil {
@@ -134,10 +133,10 @@ func (d *Dewy) Run() error {
 		}
 	}
 
-	log.Print("[DEBUG] Record shipment")
-	err = d.repo.RecordShipment()
+	log.Print("[DEBUG] Record shipping")
+	err = d.repo.RecordShipping()
 	if err != nil {
-		log.Printf("[ERROR] Record shipment failure: %#v", err)
+		log.Printf("[ERROR] Record shipping failure: %#v", err)
 	}
 
 	log.Printf("[INFO] Keep releases as %d", keepReleases)

kvs/file.go

@@ -4,6 +4,7 @@ import (
 	"errors"
 	"fmt"
 	"io/ioutil"
+	"log"
 	"os"
 	"path/filepath"
 	"sync"
@@ -73,10 +74,6 @@ func (f *File) Write(key string, data []byte) error {
 	}
 
 	p := filepath.Join(f.dir, key)
-	if IsFileExist(p) {
-		return fmt.Errorf("File already exists: %s", p)
-	}
-
 	file, err := os.OpenFile(p, os.O_CREATE|os.O_WRONLY, 0644)
 	if err != nil {
 		return err
@@ -85,6 +82,8 @@ func (f *File) Write(key string, data []byte) error {
 	defer file.Close()
 	file.Write(data)
 
+	log.Printf("[INFO] Write file to %s", p)
+
 	return nil
 }
 

repo/github_release.go

@@ -169,38 +169,56 @@ func (g *GithubRelease) setCacheKey() error {
 	return nil
 }
 
-// IsDownloadNecessary checks necessary for download
-func (g *GithubRelease) IsDownloadNecessary() bool {
+// GetDeploySourceKey returns cache key
+func (g *GithubRelease) GetDeploySourceKey() (string, error) {
+	currentKey := "current.txt"
+	currentSourceKey, _ := g.cache.Read(currentKey)
+	found := false
+
 	list, err := g.cache.List()
 	if err != nil {
-		return false
+		return "", err
 	}
 
 	for _, key := range list {
+		if string(currentSourceKey) == g.cacheKey && key == g.cacheKey {
+			return "", fmt.Errorf("No need to deploy")
+		}
+
 		if key == g.cacheKey {
-			return false
+			found = true
+			break
+		}
+	}
+
+	if !found {
+		if err := g.download(); err != nil {
+			return "", err
 		}
 	}
 
-	return true
+	if err := g.cache.Write(currentKey, []byte(g.cacheKey)); err != nil {
+		return "", err
+	}
+
+	return g.cacheKey, nil
 }
 
-// Download artifact from github
-func (g *GithubRelease) Download() (string, error) {
+func (g *GithubRelease) download() error {
 	ctx := context.Background()
 	c, err := g.client(ctx)
 	if err != nil {
-		return "", err
+		return err
 	}
 
 	reader, url, err := c.Repositories.DownloadReleaseAsset(ctx, g.owner, g.name, g.assetID)
 	if err != nil {
-		return "", err
+		return err
 	}
 	if url != "" {
 		res, err := http.Get(url)
 		if err != nil {
-			return "", err
+			return err
 		}
 		reader = res.Body
 	}
@@ -209,15 +227,15 @@ func (g *GithubRelease) Download() (string, error) {
 	buf := new(bytes.Buffer)
 	_, err = io.Copy(buf, reader)
 	if err != nil {
-		return "", err
+		return err
 	}
 
 	if err := g.cache.Write(g.cacheKey, buf.Bytes()); err != nil {
-		return "", err
+		return err
 	}
 	log.Printf("[INFO] Cached as %s", g.cacheKey)
 
-	return g.cacheKey, nil
+	return nil
 }
 
 func (g *GithubRelease) client(ctx context.Context) (*github.Client, error) {
@@ -243,8 +261,8 @@ func (g *GithubRelease) client(ctx context.Context) (*github.Client, error) {
 	return g.cl, nil
 }
 
-// RecordShipment save shipment to github
-func (g *GithubRelease) RecordShipment() error {
+// RecordShipping save shipping to github
+func (g *GithubRelease) RecordShipping() error {
 	ctx := context.Background()
 	c, err := g.client(ctx)
 	if err != nil {

repo/repo.go

@@ -10,9 +10,8 @@ import (
 type Repo interface {
 	String() string
 	Fetch() error
-	Download() (string, error)
-	IsDownloadNecessary() bool
-	RecordShipment() error
+	GetDeploySourceKey() (string, error)
+	RecordShipping() error
 	ReleaseTag() string
 	ReleaseURL() string
 	OwnerURL() string