7.9 KiB
Server List Scalability Implementation Plan
For agentic workers: REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox (
- [ ]) syntax for tracking.
Goal: Keep the server list usable when the saved server count is larger than the terminal height.
Architecture: The list screen should render a bounded table viewport instead of rendering every server row. Selection remains owned by the existing bubbles/list.Model, while viewServerList derives a visible row range around the selected item and keeps the selected-server detail panel and footer visible.
Tech Stack: Go, Bubble Tea, Bubbles list, Lip Gloss, existing TUI tests in internal/tui/app_test.go.
Task 1: Add Regression Coverage For Long Server Lists
Files:
-
Modify:
internal/tui/app_test.go -
Step 1: Add a test for a constrained terminal height
Add a test that creates more servers than can fit on screen, sets a small terminal size, renders the list, and verifies the selected details and footer are still visible.
func TestServerListViewKeepsDetailsVisibleWithManyServers(t *testing.T) {
servers := make([]*model.Server, 45)
for i := range servers {
servers[i] = &model.Server{
Alias: fmt.Sprintf("server-%02d", i+1),
DisplayName: fmt.Sprintf("Server %02d", i+1),
Host: fmt.Sprintf("host-%02d.example.org", i+1),
Port: 22,
User: "mirivlad",
AuthMethod: model.AuthKey,
LastTestStatus: model.TestUnknown,
}
}
m := New(servers)
updated, _ := m.Update(tea.WindowSizeMsg{Width: 100, Height: 18})
model := updated.(*tuiModel)
view := model.View()
if !strings.Contains(view, "Server 01") {
t.Fatalf("expected first selected server to be visible:\n%s", view)
}
if !strings.Contains(view, "Selected") {
t.Fatalf("expected selected server details to remain visible:\n%s", view)
}
if !strings.Contains(view, "Enter connect") {
t.Fatalf("expected footer to remain visible:\n%s", view)
}
if count := strings.Count(view, "server-"); count >= len(servers) {
t.Fatalf("expected bounded row rendering, rendered %d server aliases", count)
}
}
- Step 2: Run the focused test and confirm it fails
Run:
env GOCACHE=/tmp/sshkeeper-go-cache go test ./internal/tui -run TestServerListViewKeepsDetailsVisibleWithManyServers -count=1
Expected: FAIL because the current table renders every server and can push the detail panel/footer below the visible terminal area.
Task 2: Compute A Visible Row Window
Files:
-
Modify:
internal/tui/app.go -
Modify:
internal/tui/app_test.go -
Step 1: Add focused tests for visible range calculation
Add tests for a helper that computes the inclusive start and exclusive end indexes for rendered rows.
func TestVisibleServerRangeKeepsSelectionInsideWindow(t *testing.T) {
tests := []struct {
name string
total int
selected int
available int
wantStart int
wantEnd int
}{
{name: "first page", total: 40, selected: 0, available: 10, wantStart: 0, wantEnd: 10},
{name: "middle page", total: 40, selected: 20, available: 10, wantStart: 11, wantEnd: 21},
{name: "last page", total: 40, selected: 39, available: 10, wantStart: 30, wantEnd: 40},
{name: "all fit", total: 5, selected: 3, available: 10, wantStart: 0, wantEnd: 5},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
start, end := visibleServerRange(tt.total, tt.selected, tt.available)
if start != tt.wantStart || end != tt.wantEnd {
t.Fatalf("visibleServerRange() = %d, %d; want %d, %d", start, end, tt.wantStart, tt.wantEnd)
}
})
}
}
- Step 2: Implement
visibleServerRange
Add a small helper near selectedServer.
func visibleServerRange(total, selected, available int) (int, int) {
if total <= 0 || available <= 0 {
return 0, 0
}
if available >= total {
return 0, total
}
if selected < 0 {
selected = 0
}
if selected >= total {
selected = total - 1
}
start := selected - available + 1
if start < 0 {
start = 0
}
end := start + available
if end > total {
end = total
start = end - available
}
return start, end
}
- Step 3: Run helper tests
Run:
env GOCACHE=/tmp/sshkeeper-go-cache go test ./internal/tui -run TestVisibleServerRangeKeepsSelectionInsideWindow -count=1
Expected: PASS.
Task 3: Render Only Rows That Fit
Files:
-
Modify:
internal/tui/app.go -
Modify:
internal/tui/app_test.go -
Step 1: Reserve terminal space for fixed UI blocks
Add a helper that decides how many server rows may be rendered while keeping the selected details and footer visible.
func (m *tuiModel) visibleServerRows() int {
if m.height <= 0 {
return len(m.servers)
}
const fixedRows = 16
rows := m.height - fixedRows
if rows < 3 {
return 3
}
return rows
}
- Step 2: Use the visible range in
viewServerList
In viewServerList, replace the loop over all servers with a bounded loop:
selectedIndex := m.list.Index()
start, end := visibleServerRange(len(m.servers), selectedIndex, m.visibleServerRows())
for _, server := range m.servers[start:end] {
// existing row rendering body stays unchanged
}
Then render a compact range hint when rows are hidden:
if len(m.servers) > end-start {
b.WriteString(helpStyle.Render(fmt.Sprintf(" Showing %d-%d of %d", start+1, end, len(m.servers))))
b.WriteString("\n")
}
- Step 3: Run long-list regression test
Run:
env GOCACHE=/tmp/sshkeeper-go-cache go test ./internal/tui -run TestServerListViewKeepsDetailsVisibleWithManyServers -count=1
Expected: PASS.
Task 4: Verify Navigation Still Works
Files:
-
Modify:
internal/tui/app_test.go -
Step 1: Add a test for moving selection beyond the first window
Use the existing m.list.Update path by sending tea.KeyDown messages and confirm the rendered window follows the selected server.
func TestServerListViewScrollsWithSelection(t *testing.T) {
servers := make([]*model.Server, 45)
for i := range servers {
servers[i] = &model.Server{
Alias: fmt.Sprintf("server-%02d", i+1),
DisplayName: fmt.Sprintf("Server %02d", i+1),
Host: fmt.Sprintf("host-%02d.example.org", i+1),
Port: 22,
User: "mirivlad",
AuthMethod: model.AuthKey,
}
}
m := New(servers)
updated, _ := m.Update(tea.WindowSizeMsg{Width: 100, Height: 18})
model := updated.(*tuiModel)
for i := 0; i < 20; i++ {
updated, _ = model.Update(tea.KeyMsg{Type: tea.KeyDown})
model = updated.(*tuiModel)
}
view := model.View()
if !strings.Contains(view, "Server 21") {
t.Fatalf("expected selected server to be visible after navigation:\n%s", view)
}
if !strings.Contains(view, "Showing") {
t.Fatalf("expected range hint for long server list:\n%s", view)
}
}
- Step 2: Run TUI tests
Run:
env GOCACHE=/tmp/sshkeeper-go-cache go test ./internal/tui -count=1
Expected: PASS.
Task 5: Final Verification And Build
Files:
-
No source edits expected.
-
Step 1: Run the full test suite
Run:
env GOCACHE=/tmp/sshkeeper-go-cache go test ./...
Expected: all packages pass.
- Step 2: Rebuild the project binary
Run:
env GOCACHE=/tmp/sshkeeper-go-cache go build -o bin/sshkeeper .
Expected: exit code 0 and updated bin/sshkeeper.
- Step 3: Commit the implementation
Run:
git add internal/tui/app.go internal/tui/app_test.go bin/sshkeeper
git commit -m "fix: keep server list usable with many servers"
Expected: commit succeeds.
Self-Review
- Spec coverage: the plan covers the known failure mode for 40+ servers, keeps selected details visible, keeps the footer visible, and preserves existing
bubbles/listnavigation. - Placeholder scan: no
TBD,TODO, or open-ended implementation placeholders remain. - Type consistency: helper names and files match the current TUI code shape.