Exclude timestamp (updatedAt) from cache key

Cache key should be able to be specified with just a tag.

However, currently, "extension" is required, so it is implemented with tag and URL.

dewy.go

@@ -5,12 +5,10 @@ import (
 	"context"
 	"fmt"
 	"log"
-	"net/url"
 	"os"
 	"os/signal"
 	"path/filepath"
 	"sort"
-	"strings"
 	"sync"
 	"syscall"
 	"time"
@@ -115,20 +113,17 @@ func (d *Dewy) Run() error {
 	ctx, cancel := context.WithCancel(context.Background())
 	defer cancel()
 
-	if err := d.repo.Fetch(); err != nil {
-		log.Printf("[ERROR] Fetch failure: %#v", err)
-		return err
-	}
-
-	// Create latest cache key
-	du, ut := d.repo.LatestKey()
-	u, err := url.Parse(du)
+	// Get current
+	res, err := d.repo.Current(&repo.CurrentRequest{
+		ArtifactName: d.config.Repository.Artifact,
+	})
 	if err != nil {
+		log.Printf("[ERROR] Current failure: %#v", err)
 		return err
 	}
-	cacheKey := strings.Replace(fmt.Sprintf("%s--%d-%s", u.Host, ut.Unix(), u.RequestURI()), "/", "-", -1)
 
 	// Check cache
+	cacheKey := fmt.Sprintf("%s-%s", res.Tag, filepath.Base(res.ArtifactURL))
 	currentKey := "current.txt"
 	currentSourceKey, _ := d.cache.Read(currentKey)
 	found := false

repo/github_release.go

@@ -34,7 +34,6 @@ type GithubRelease struct {
 	name                  string
 	artifact              string
 	downloadURL           string
-	cacheKey              string
 	releaseID             int64
 	assetID               int64
 	releaseURL            string
@@ -103,32 +102,37 @@ func (g *GithubRelease) ReleaseURL() string {
 	return g.releaseURL
 }
 
-// Fetch to latest github release
-func (g *GithubRelease) Fetch() error {
+func (g *GithubRelease) Current(req *CurrentRequest) (*CurrentResponse, error) {
 	release, err := g.latest()
 	if err != nil {
-		return err
+		return nil, err
 	}
 
 	g.releaseID = *release.ID
 	g.releaseURL = *release.HTMLURL
 
+	found := false
 	for _, v := range release.Assets {
-		if *v.Name == g.artifact {
+		if v.GetName() == req.ArtifactName {
+			found = true
 			log.Printf("[DEBUG] Fetched: %+v", v)
-			g.downloadURL = *v.BrowserDownloadURL
-			g.releaseTag = *release.TagName
-			g.assetID = *v.ID
-			g.updatedAt = *v.UpdatedAt
+			g.downloadURL = v.GetBrowserDownloadURL()
+			g.releaseTag = release.GetTagName()
+			g.assetID = v.GetID()
+			g.updatedAt = v.GetUpdatedAt()
 			break
 		}
 	}
+	if !found {
+		return nil, fmt.Errorf("artifact not found: %s", req.ArtifactName)
+	}
 
-	return nil
-}
+	au := fmt.Sprintf("github_release://%s/%s/tag/%s/%s", g.owner, g.name, release.GetTagName(), req.ArtifactName)
 
-func (g *GithubRelease) LatestKey() (string, time.Time) {
-	return g.downloadURL, g.updatedAt.Time
+	return &CurrentResponse{
+		Tag:         release.GetTagName(),
+		ArtifactURL: au,
+	}, nil
 }
 
 func (g *GithubRelease) latest() (*github.RepositoryRelease, error) {

repo/repo.go

@@ -4,19 +4,33 @@ import (
 	"errors"
 	"io"
 	"path"
-	"time"
 )
 
+// CurrentRequest is the request to get the current artifact.
+type CurrentRequest struct {
+	// ArtifactName is the name of the artifact to fetch.
+	// FIXME: If possible, ArtifactName should be optional.
+	ArtifactName string
+}
+
+// CurrentResponse is the response to get the current artifact.
+type CurrentResponse struct {
+	// Tag uniquely identifies the artifact concerned.
+	Tag string
+	// ArtifactURL is the URL to download the artifact.
+	// The URL is not only "https://"
+	ArtifactURL string
+}
+
 // Repo interface for repository
 type Repo interface {
 	String() string
-	Fetch() error
 	RecordShipping() error
 	ReleaseTag() string
 	ReleaseURL() string
 	OwnerURL() string
 	OwnerIconURL() string
-	LatestKey() (string, time.Time)
+	Current(req *CurrentRequest) (*CurrentResponse, error)
 	Download(w io.Writer) error
 	URL() string
 }