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Add WAL for direct deployment state recovery #4106

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57 changes: 41 additions & 16 deletions bundle/direct/dstate/state.go
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Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -22,6 +22,14 @@ type Database struct {
Lineage string `json:"lineage"`
Serial int `json:"serial"`
State map[string]ResourceEntry `json:"state"`
WAL []LogEntry `json:"wal,omitempty"`
}

type LogEntry struct {
Op string `json:"op"`
Key string `json:"key"`
ID string `json:"id,omitempty"`
State any `json:"state,omitempty"`
}

type ResourceEntry struct {
Expand All @@ -34,15 +42,16 @@ func (db *DeploymentState) SaveState(key, newID string, state any) error {
db.mu.Lock()
defer db.mu.Unlock()

if db.Data.State == nil {
db.Data.State = make(map[string]ResourceEntry)
db.Data.WAL = append(db.Data.WAL, LogEntry{Op: "save", Key: key, ID: newID, State: state})
if err := db.writeState(); err != nil {
db.Data.WAL = db.Data.WAL[:len(db.Data.WAL)-1] // Rollback on failure
return err
}

db.Data.State[key] = ResourceEntry{
ID: newID,
State: state,
if db.Data.State == nil {
db.Data.State = make(map[string]ResourceEntry)
}

db.Data.State[key] = ResourceEntry{ID: newID, State: state}
return nil
}

Expand All @@ -51,12 +60,13 @@ func (db *DeploymentState) DeleteState(key string) error {
db.mu.Lock()
defer db.mu.Unlock()

if db.Data.State == nil {
return nil
db.Data.WAL = append(db.Data.WAL, LogEntry{Op: "delete", Key: key})
if err := db.writeState(); err != nil {
db.Data.WAL = db.Data.WAL[:len(db.Data.WAL)-1] // Rollback on failure
return err
}

delete(db.Data.State, key)

return nil
}

Expand Down Expand Up @@ -104,14 +114,21 @@ func (db *DeploymentState) Open(path string) error {
}

db.Path = path
db.replayWAL()
return nil
}

func (db *DeploymentState) Finalize() error {
db.mu.Lock()
defer db.mu.Unlock()

return db.unlockedSave()
oldWAL := db.Data.WAL
db.Data.WAL = nil
if err := db.writeState(); err != nil {
db.Data.WAL = oldWAL // Restore on failure
return err
}
return nil
}

func (db *DeploymentState) AssertOpened() {
Expand Down Expand Up @@ -148,17 +165,25 @@ func (db *DeploymentState) ExportState(ctx context.Context) resourcestate.Export
return result
}

func (db *DeploymentState) unlockedSave() error {
func (db *DeploymentState) writeState() error {
db.AssertOpened()
data, err := json.MarshalIndent(db.Data, "", " ")
if err != nil {
return err
}
return os.WriteFile(db.Path, data, 0o600)
}

err = os.WriteFile(db.Path, data, 0o600)
if err != nil {
return fmt.Errorf("failed to save resources state to %#v: %w", db.Path, err)
func (db *DeploymentState) replayWAL() {
for _, entry := range db.Data.WAL {
switch entry.Op {
case "save":
if db.Data.State == nil {
db.Data.State = make(map[string]ResourceEntry)
}
db.Data.State[entry.Key] = ResourceEntry{ID: entry.ID, State: entry.State}
case "delete":
delete(db.Data.State, entry.Key)
}
}

return nil
}
193 changes: 193 additions & 0 deletions bundle/direct/dstate/state_test.go
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Original file line number Diff line number Diff line change
@@ -0,0 +1,193 @@
package dstate

import (
"encoding/json"
"os"
"path/filepath"
"testing"

"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
)

func TestWALSaveAndReplay(t *testing.T) {
tmpDir := t.TempDir()
statePath := filepath.Join(tmpDir, "state.json")

db := &DeploymentState{}
err := db.Open(statePath)
require.NoError(t, err)

err = db.SaveState("resources.jobs.job1", "123", map[string]any{"name": "job1"})
require.NoError(t, err)

err = db.SaveState("resources.jobs.job2", "456", map[string]any{"name": "job2"})
require.NoError(t, err)

// Verify WAL exists in file
data, err := os.ReadFile(statePath)
require.NoError(t, err)
var loaded Database
require.NoError(t, json.Unmarshal(data, &loaded))
assert.Len(t, loaded.WAL, 2)

// Simulate crash: open a new state (WAL replays on open)
db2 := &DeploymentState{}
err = db2.Open(statePath)
require.NoError(t, err)

entry1, ok := db2.GetResourceEntry("resources.jobs.job1")
assert.True(t, ok)
assert.Equal(t, "123", entry1.ID)

entry2, ok := db2.GetResourceEntry("resources.jobs.job2")
assert.True(t, ok)
assert.Equal(t, "456", entry2.ID)
}

func TestWALDeleteAndReplay(t *testing.T) {
tmpDir := t.TempDir()
statePath := filepath.Join(tmpDir, "state.json")

db := &DeploymentState{}
err := db.Open(statePath)
require.NoError(t, err)

err = db.SaveState("resources.jobs.job1", "123", map[string]any{"name": "job1"})
require.NoError(t, err)

err = db.SaveState("resources.jobs.job2", "456", map[string]any{"name": "job2"})
require.NoError(t, err)

err = db.DeleteState("resources.jobs.job1")
require.NoError(t, err)

// Simulate crash and reopen
db2 := &DeploymentState{}
err = db2.Open(statePath)
require.NoError(t, err)

_, ok := db2.GetResourceEntry("resources.jobs.job1")
assert.False(t, ok, "job1 should be deleted")

entry2, ok := db2.GetResourceEntry("resources.jobs.job2")
assert.True(t, ok)
assert.Equal(t, "456", entry2.ID)
}

func TestWALFinalizeClearsWAL(t *testing.T) {
tmpDir := t.TempDir()
statePath := filepath.Join(tmpDir, "state.json")

db := &DeploymentState{}
err := db.Open(statePath)
require.NoError(t, err)

err = db.SaveState("resources.jobs.job1", "123", map[string]any{"name": "job1"})
require.NoError(t, err)

// Verify WAL has entries before finalize
data, err := os.ReadFile(statePath)
require.NoError(t, err)
var before Database
require.NoError(t, json.Unmarshal(data, &before))
assert.NotEmpty(t, before.WAL)

err = db.Finalize()
require.NoError(t, err)

// Verify WAL is cleared after finalize
data, err = os.ReadFile(statePath)
require.NoError(t, err)
var after Database
require.NoError(t, json.Unmarshal(data, &after))
assert.Empty(t, after.WAL)

// State still has the entry
db2 := &DeploymentState{}
err = db2.Open(statePath)
require.NoError(t, err)

entry, ok := db2.GetResourceEntry("resources.jobs.job1")
assert.True(t, ok)
assert.Equal(t, "123", entry.ID)
}

func TestWALWithExistingState(t *testing.T) {
tmpDir := t.TempDir()
statePath := filepath.Join(tmpDir, "state.json")

// Create state with one entry and finalize
db := &DeploymentState{}
err := db.Open(statePath)
require.NoError(t, err)

err = db.SaveState("resources.jobs.job1", "123", map[string]any{"name": "job1"})
require.NoError(t, err)

err = db.Finalize()
require.NoError(t, err)

// Open again and add more entries without finalizing
db2 := &DeploymentState{}
err = db2.Open(statePath)
require.NoError(t, err)

err = db2.SaveState("resources.jobs.job2", "456", map[string]any{"name": "job2"})
require.NoError(t, err)

// Simulate crash and reopen
db3 := &DeploymentState{}
err = db3.Open(statePath)
require.NoError(t, err)

entry1, ok := db3.GetResourceEntry("resources.jobs.job1")
assert.True(t, ok)
assert.Equal(t, "123", entry1.ID)

entry2, ok := db3.GetResourceEntry("resources.jobs.job2")
assert.True(t, ok)
assert.Equal(t, "456", entry2.ID)
}

func TestWALUpdateExistingEntry(t *testing.T) {
tmpDir := t.TempDir()
statePath := filepath.Join(tmpDir, "state.json")

db := &DeploymentState{}
err := db.Open(statePath)
require.NoError(t, err)

err = db.SaveState("resources.jobs.job1", "123", map[string]any{"name": "job1"})
require.NoError(t, err)

err = db.SaveState("resources.jobs.job1", "789", map[string]any{"name": "job1-updated"})
require.NoError(t, err)

// Simulate crash and reopen
db2 := &DeploymentState{}
err = db2.Open(statePath)
require.NoError(t, err)

entry, ok := db2.GetResourceEntry("resources.jobs.job1")
assert.True(t, ok)
assert.Equal(t, "789", entry.ID)
}

func TestNoStateFile(t *testing.T) {
tmpDir := t.TempDir()
statePath := filepath.Join(tmpDir, "state.json")

db := &DeploymentState{}
err := db.Open(statePath)
require.NoError(t, err)

err = db.Finalize()
require.NoError(t, err)

db2 := &DeploymentState{}
err = db2.Open(statePath)
require.NoError(t, err)

assert.NotEmpty(t, db2.Data.Lineage)
}