Improve module deprecation check (#153)

The deprecation check queries the api each time also if the module is
already in the cache. This slows down the sync unnecessarily.

Improve this by reparsing the file when it is in the cache to continue
printing known deprecations and use the module TTL to refresh the
deprecation cache.

Closes #152

forge.go

@@ -22,10 +22,32 @@ import (
 	"github.com/xorpaul/uiprogress"
 )
 
+func checkDeprecation(fm ForgeModule, lastCheckedFile string) (bool) {
+	// check content of lastCheckedFile (which should be the Forge API response body) if the module is deprecated
+	// return false if the api needs to be queried again
+	if fileInfo, err := os.Stat(lastCheckedFile); err == nil {
+		if fileInfo.Size() < 1 {
+			Debugf("found empty file " + lastCheckedFile)
+			return false
+		} else if fm.cacheTTL > 0 && fileInfo.ModTime().Add(fm.cacheTTL).Before(time.Now()) {
+			return false
+		} else {
+			json, err := ioutil.ReadFile(lastCheckedFile)
+			if err != nil {
+				Fatalf("doModuleInstallOrNothing(): Error while reading Forge API result from file " + lastCheckedFile + err.Error())
+			}
+			_ = parseForgeAPIResult(string(json), fm)
+			return true
+		}
+	}
+	return false
+}
+
 func doModuleInstallOrNothing(fm ForgeModule) {
 	moduleName := fm.author + "-" + fm.name
 	moduleVersion := fm.version
 	workDir := filepath.Join(config.ForgeCacheDir, moduleName+"-"+fm.version)
+	lastCheckedFile := filepath.Join(config.ForgeCacheDir, moduleName+"-latest-last-checked")
 	fr := ForgeResult{false, fm.version, "", 0}
 	if check4update {
 		moduleVersion = "latest"
@@ -56,7 +78,6 @@ func doModuleInstallOrNothing(fm ForgeModule) {
 			}
 		} else {
 			if fm.cacheTTL > 0 {
-				lastCheckedFile := workDir + "-last-checked"
 				//Debugf("checking for " + lastCheckedFile)
 				if fileInfo, err := os.Lstat(lastCheckedFile); err == nil {
 					//Debugf("found " + lastCheckedFile + " with mTime " + fileInfo.ModTime().String())
@@ -68,20 +89,8 @@ func doModuleInstallOrNothing(fm ForgeModule) {
 						latestForgeModules.m[moduleName] = me.version
 						latestForgeModules.Unlock()
 
-						// check content of lastCheckedFile (which should be the Forge API response body) if the module is deprecated
-
-						if fi, err := os.Stat(lastCheckedFile); err == nil {
-							if fi.Size() < 1 {
-								Debugf("found empty file " + lastCheckedFile)
-								fr = queryForgeAPI(fm)
-							} else {
-								json, err := ioutil.ReadFile(lastCheckedFile)
-								if err != nil {
-									Fatalf("doModuleInstallOrNothing(): Error while reading Forge API result from file " + lastCheckedFile + err.Error())
-								}
-								_ = parseForgeAPIResult(string(json), fm)
-								return
-							}
+						if checkDeprecation(fm, lastCheckedFile) {
+							return
 						}
 
 					}
@@ -111,11 +120,13 @@ func doModuleInstallOrNothing(fm ForgeModule) {
 		}
 		Debugf("Nothing to do for module " + fm.author + "-" + fm.name + "-" + fm.version + ", because " + latestDir + " exists")
 	} else {
-		// check for deprecation notice
-		_ = queryForgeAPI(fm)
 		if !isDir(workDir) {
+			_ = queryForgeAPI(fm)
 			fr.needToGet = true
 		} else {
+			if !checkDeprecation(fm, lastCheckedFile) {
+				_ = queryForgeAPI(fm)
+			}
 			Debugf("Using cache for " + moduleName + " in version " + moduleVersion + " because " + workDir + " exists")
 			return
 		}