refactor(recipe): better naming, sorting and types

In order to arrange various types of sorting for the app catalogue, it
seems like the recommended approach is to maintain a separate data
structure alongside the JSON map we get from apps.coopcloud.tech.

Therefore, I attempt to provide a ToList() method and accompanying
sort.Sort interface sorting implementations. For now, this is just
sorting by app name.

I am testing this type of implementation here before moving on to
arrange different types of sorting for the `app list` command.

cli/recipe.go

@@ -8,6 +8,7 @@ import (
 	"os"
 	"path"
 	"sort"
+	"strings"
 	"text/template"
 	"time"
 
@@ -34,38 +35,48 @@ type Feature struct {
 	Tests       string `json:"tests"`
 }
 
-type Version struct {
+type Tag = string
+type Service = string
+type ServiceMeta struct {
 	Digest string `json:"digest"`
 	Image  string `json:"image"`
 	Tag    string `json:"tag"`
 }
 
 type App struct {
-	Category      string                        `json:"category"`
-	DefaultBranch string                        `json:"default_branch"`
-	Description   string                        `json:"description"`
-	Features      Feature                       `json:"features"`
-	Icon          string                        `json:"icon"`
-	Name          string                        `json:"name"`
-	Repository    string                        `json:"repository"`
-	Versions      map[string]map[string]Version `json:"versions"`
-	Website       string                        `json:"website"`
+	Category      string                          `json:"category"`
+	DefaultBranch string                          `json:"default_branch"`
+	Description   string                          `json:"description"`
+	Features      Feature                         `json:"features"`
+	Icon          string                          `json:"icon"`
+	Name          string                          `json:"name"`
+	Repository    string                          `json:"repository"`
+	Versions      map[Tag]map[Service]ServiceMeta `json:"versions"`
+	Website       string                          `json:"website"`
 }
 
-type Apps map[string]App
+type Name = string
+type AppsCatalogue map[Name]App
 
-func (a Apps) SortByName() []string {
-	var names []string
+func (a AppsCatalogue) ToList() []App {
+	apps := make([]App, 0, len(a))
 	for name := range a {
-		names = append(names, name)
+		apps = append(apps, a[name])
 	}
-	sort.Strings(names)
-	return names
+	return apps
+}
+
+type ByAppName []App
+
+func (a ByAppName) Len() int      { return len(a) }
+func (a ByAppName) Swap(i, j int) { a[i], a[j] = a[j], a[i] }
+func (a ByAppName) Less(i, j int) bool {
+	return strings.ToLower(a[i].Name) < strings.ToLower(a[j].Name)
 }
 
 var httpClient = &http.Client{Timeout: 5 * time.Second}
 
-var AppsUrl = "https://apps.coopcloud.tech"
+var AppsCatalogueURL = "https://apps.coopcloud.tech"
 
 func readJson(url string, target interface{}) error {
 	res, err := httpClient.Get(url)
@@ -76,8 +87,8 @@ func readJson(url string, target interface{}) error {
 	return json.NewDecoder(res.Body).Decode(target)
 }
 
-func AppsFSIsLatest() (bool, error) {
-	res, err := httpClient.Head(AppsUrl)
+func AppsCatalogueFSIsLatest() (bool, error) {
+	res, err := httpClient.Head(AppsCatalogueURL)
 	if err != nil {
 		return false, err
 	}
@@ -106,29 +117,29 @@ func AppsFSIsLatest() (bool, error) {
 	return true, nil
 }
 
-func ReadApps() (Apps, error) {
-	apps := make(Apps)
+func ReadAppsCatalogue() (AppsCatalogue, error) {
+	apps := make(AppsCatalogue)
 
-	appsFSIsLatest, err := AppsFSIsLatest()
+	appsFSIsLatest, err := AppsCatalogueFSIsLatest()
 	if err != nil {
 		return nil, err
 	}
 
 	if !appsFSIsLatest {
-		if err := ReadAppsWeb(&apps); err != nil {
+		if err := ReadAppsCatalogueWeb(&apps); err != nil {
 			return nil, err
 		}
 		return apps, nil
 	}
 
-	if err := ReadAppsFS(&apps); err != nil {
+	if err := ReadAppsCatalogueFS(&apps); err != nil {
 		return nil, err
 	}
 
 	return apps, nil
 }
 
-func ReadAppsFS(target interface{}) error {
+func ReadAppsCatalogueFS(target interface{}) error {
 	appsJsonFS, err := ioutil.ReadFile(config.APPS_JSON)
 	if err != nil {
 		return err
@@ -139,8 +150,8 @@ func ReadAppsFS(target interface{}) error {
 	return nil
 }
 
-func ReadAppsWeb(target interface{}) error {
-	if err := readJson(AppsUrl, &target); err != nil {
+func ReadAppsCatalogueWeb(target interface{}) error {
+	if err := readJson(AppsCatalogueURL, &target); err != nil {
 		return err
 	}
 
@@ -160,14 +171,15 @@ var recipeListCommand = &cli.Command{
 	Name:    "list",
 	Aliases: []string{"ls"},
 	Action: func(c *cli.Context) error {
-		apps, err := ReadApps()
+		catalogue, err := ReadAppsCatalogue()
 		if err != nil {
 			logrus.Fatal(err.Error())
 		}
+		apps := catalogue.ToList()
+		sort.Sort(ByAppName(apps))
 		tableCol := []string{"Name", "Category", "Status"}
 		table := createTable(tableCol)
-		for _, name := range apps.SortByName() {
-			app := apps[name]
+		for _, app := range apps {
 			status := fmt.Sprintf("%v", app.Features.Status)
 			tableRow := []string{app.Name, app.Category, status}
 			table.Append(tableRow)
@@ -188,7 +200,7 @@ var recipeVersionCommand = &cli.Command{
 			return nil
 		}
 
-		apps, err := ReadApps()
+		apps, err := ReadAppsCatalogue()
 		if err != nil {
 			logrus.Fatal(err)
 			return nil