WIP: app status listing using concurrency

This being my first time using goroutines, it is pretty messy but the
idea has been shown to be workable! We can concurrently look up multiple
contexts for a much faster response time especially when using multiple
servers.

Remaining TODOs are:

- [ ] Get proper status reporting (deployed/inactive/unknown)
- [ ] Error handling (especially when missing contexts)
- [ ] Refactor and tidy

cli/app.go

@@ -59,27 +59,35 @@ var appListCommand = &cli.Command{
 			logrus.Fatal(err)
 		}
 
+		apps, err := config.GetApps(appFiles)
+		sort.Sort(config.ByServerAndType(apps))
+
+		statuses := map[string]string{}
 		tableCol := []string{"Server", "Type", "Domain"}
 		if Status {
-			tableCol = []string{"Server", "Type", "Domain", "Status"}
+			tableCol = append(tableCol, "Status")
+			statuses, err = config.GetAppStatuses(appFiles)
+			if err != nil {
+				logrus.Fatal(err)
+			}
 		}
+
 		table := createTable(tableCol)
 		table.SetAutoMergeCellsByColumnIndex([]int{0})
 
-		apps, err := config.GetApps(appFiles)
-		sort.Sort(config.ByServerAndType(apps))
 		for _, app := range apps {
 			var tableRow []string
 			if app.Type == Type || Type == "" {
 				// If type flag is set, check for it, if not, Type == ""
 				tableRow = []string{app.File.Server, app.Type, app.Domain}
-			}
-			if Status {
-				status, err := app.GetStatus()
-				if err != nil {
-					logrus.Fatal(err)
+				if Status {
+					stackName := strings.ReplaceAll(app.Name, ".", "_")
+					if status, ok := statuses[stackName]; ok {
+						tableRow = append(tableRow, status)
+					} else {
+						tableRow = append(tableRow, "unknown")
+					}
 				}
-				tableRow = []string{app.File.Server, app.Type, app.Domain, status}
 			}
 			table.Append(tableRow)
 		}