fix: more robust docker context problem handling

See coop-cloud/organising#325
See coop-cloud/organising#340

cli/server/list.go

@@ -12,11 +12,20 @@ import (
 	"github.com/urfave/cli"
 )
 
+var problemsFilter bool
+
+var problemsFilterFlag = &cli.BoolFlag{
+	Name:        "problems, p",
+	Usage:       "Show only servers with potential connection problems",
+	Destination: &problemsFilter,
+}
+
 var serverListCommand = cli.Command{
 	Name:    "list",
 	Aliases: []string{"ls"},
 	Usage:   "List managed servers",
 	Flags: []cli.Flag{
+		problemsFilterFlag,
 		internal.DebugFlag,
 		internal.MachineReadableFlag,
 	},
@@ -48,6 +57,7 @@ var serverListCommand = cli.Command{
 					// No local context found, we can continue safely
 					continue
 				}
+
 				if ctx.Name == serverName {
 					sp, err := ssh.ParseURL(endpoint)
 					if err != nil {
@@ -56,6 +66,7 @@ var serverListCommand = cli.Command{
 					row = []string{serverName, sp.Host, sp.User, sp.Port}
 				}
 			}
+
 			if len(row) == 0 {
 				if serverName == "default" {
 					row = []string{serverName, "local", "n/a", "n/a"}
@@ -63,7 +74,14 @@ var serverListCommand = cli.Command{
 					row = []string{serverName, "unknown", "unknown", "unknown"}
 				}
 			}
-			table.Append(row)
+
+			if problemsFilter {
+				if row[1] == "unknown" {
+					table.Append(row)
+				}
+			} else {
+				table.Append(row)
+			}
 		}
 
 		return nil