diff --git a/README.md b/README.md index 486233a..488ac1e 100644 --- a/README.md +++ b/README.md @@ -566,9 +566,18 @@ is both the simplest and the only complete rule: `events-3f2a1c9e-....db`. The only other file is `webhooker.lock`, the always-empty [single-instance lock](#single-instance-lock); it holds no state and is not part of the backup set — a copied one is stale and -blocks nothing. No `-wal` or `-shm` files are produced (see below); a -transient `{name}.db-journal` may exist beside a database while a write -is in flight and is not part of the backup set either. +blocks nothing. + +**`-wal` and `-shm` sidecars.** Every database runs in WAL journal mode, +so while the service is running each `{name}.db` has a `{name}.db-wal` +and a `{name}.db-shm` beside it. **`-wal` is part of the database, not a +scratch file**: it holds committed transactions that are not yet in the +`.db`, so a copy of the `.db` without its `-wal` is missing data and may +have no readable schema at all. A clean shutdown checkpoints and removes +both sidecars, so a stopped deployment has none; a killed or crashed one +leaves them, and they must be carried with the `.db`. `-shm` is +regenerable, but there is no reason to separate the two — copy the +directory. Configuration is **not** in `DATA_DIR` — it comes from the environment and from a `.env` file read out of the process working directory. Back @@ -576,17 +585,19 @@ that up with your deployment config, separately. ### A hot copy is not safe -No `journal_mode` pragma is ever issued on any database webhooker opens, -so all of them run on SQLite's default rollback journal. There is no -WAL. The main and event databases are also held open for the entire -process lifetime — `WebhookDBManager` caches event database handles and -closes them only on webhook deletion or shutdown — so "it looked idle" -is not a guarantee that nothing was mid-transaction. +Every database webhooker opens runs in WAL journal mode. The main and +event databases are also held open for the entire process lifetime — +`WebhookDBManager` caches event database handles and closes them only on +webhook deletion or shutdown — so "it looked idle" is not a guarantee +that nothing was mid-transaction. That means `cp`, `rsync`, `tar` or a filesystem snapshot taken against a -running instance can capture a database mid-transaction and yield a file -that is corrupt or missing state the journal would have rolled back. Use -one of the two procedures below instead. +running instance can capture a database and its `-wal` at two different +instants and yield a file that is corrupt or missing state. Copying a +`.db` on its own is worse and fails loudly: recently written pages, +including the schema itself on a young database, live in the `-wal`, so +the copy reads back as an empty or table-less database. Use one of the +two procedures below instead. **Stop, copy, start.** The simplest, needs no extra tooling, and the only one that gives a single point in time across every file: @@ -605,8 +616,9 @@ for db in /path/to/data/*.db; do done ``` -`.backup` takes the proper locks and writes a consistent file. Two -caveats. First, the runtime image is `alpine:3.21` with only +`.backup` reads through the WAL and writes a single consistent file with +no sidecars of its own, so the destination is complete as it stands. +Two caveats. First, the runtime image is `alpine:3.21` with only `ca-certificates` added — the `sqlite3` CLI is **not** in it, so run this on the host against the volume path, or from a throwaway container that mounts the volume. Second, each file is captured at its own @@ -614,12 +626,21 @@ instant, so a webhook created or an event delivered between two files being copied lands in one and not the other. If you need the whole set coherent as of a single moment, stop the service. +Note that `sqlite3 .dump` is **not** one of these procedures: it is +an export, it holds a read transaction open for as long as it runs, and +it pins the WAL against checkpointing for that whole time. It is safe to +run — it does not block ingestion — but back up with `.backup` or a +stopped copy. + Archive databases are the one exception the service is built for: the archive writer closes its handle after each write (debounced to at most one reopen per second), so an operator can move `archive-{uuid}.db` away for offline retention while the service runs, and it is recreated -on the next write (see -[Database Architecture](#database-architecture)). That is a +on the next write. Closing the handle checkpoints and removes that +file's sidecars, so what is left to move is a single self-contained +`.db` — but if a `-wal` is there, a write is in flight, and it has to +move with it. See +[Database Architecture](#database-architecture). That is a move-the-file-away workflow, not a substitute for the backup procedures above. @@ -636,14 +657,18 @@ above. restored without `webhooker.db` are simply orphaned; nothing references their UUIDs. -3. Do not carry `*.db-journal` files into the restore. Backups taken by - either procedure above are self-consistent and do not need one. +3. Carry any `*.db-wal` and `*.db-shm` files that are in the backup. + They are part of the database, and dropping a `-wal` silently + discards every transaction it still holds. Backups taken by either + procedure above will not contain them — `.backup` writes a single + consolidated file, and a clean stop checkpoints the sidecars away — + but a copy salvaged from a crashed instance will, and it needs them. 4. **Fix ownership.** The container runs as the non-root `webhooker` user, UID 1000 / GID 1000. Restored files must be owned by (or writable by) that UID, and so must the directory itself — SQLite - creates the rollback journal beside the database, so a writable file - inside a directory it cannot write is not enough: + creates the `-wal` and `-shm` sidecars beside the database, so a + writable file inside a directory it cannot write is not enough: ```bash chown -R 1000:1000 /path/to/data @@ -1391,10 +1416,12 @@ This separation provides: only, or disables cleanup entirely when set to `0` (retain forever). - **Performance** — each webhook's database has its own page cache and its own lock, so concurrent event ingestion across webhooks won't - contend. No write-ahead log is involved: both DSNs are - `file:{path}?cache=shared&mode=rwc` and no `journal_mode` pragma is - ever issued, so every database runs on SQLite's default rollback - journal. + contend. Every database — main, per-webhook, and archive — is opened + through one code path (`internal/database/sqlite_open.go`) in WAL + journal mode, with a 10-second busy timeout, `BEGIN IMMEDIATE` + transactions, and a bounded connection pool. Under WAL a reader never + blocks a writer, so an operator reading a database does not stall + event ingestion into it. The **database target type** builds on this architecture to provide long-term archiving, separate from the per-webhook event database (which diff --git a/internal/database/database.go b/internal/database/database.go index e92b440..f2880e8 100644 --- a/internal/database/database.go +++ b/internal/database/database.go @@ -4,7 +4,6 @@ package database import ( "context" "crypto/rand" - "database/sql" "encoding/base64" "errors" "fmt" @@ -16,7 +15,6 @@ import ( "go.uber.org/fx" "gorm.io/driver/sqlite" "gorm.io/gorm" - _ "modernc.org/sqlite" // Pure Go SQLite driver "sneak.berlin/go/webhooker/internal/banner" "sneak.berlin/go/webhooker/internal/config" "sneak.berlin/go/webhooker/internal/gormlog" @@ -198,13 +196,11 @@ func (d *Database) connectTo(dataDir string) error { // Construct the main application database path inside DATA_DIR. dbPath := filepath.Join(dataDir, MainDBFileName) - dbURL := fmt.Sprintf( - "file:%s?cache=shared&mode=rwc", - dbPath, - ) - // Open the database with the pure Go SQLite driver - sqlDB, err := sql.Open("sqlite", dbURL) + // Opened through OpenSQLite so this handle carries the same WAL + // journaling, busy timeout, immediate-transaction locking, and pool + // bounds as every other database file. See sqlite_open.go. + sqlDB, err := OpenSQLite(dbPath, SQLiteModeCreate) if err != nil { d.log.Error( "failed to open database", diff --git a/internal/database/sqlite_open.go b/internal/database/sqlite_open.go new file mode 100644 index 0000000..e0a16ae --- /dev/null +++ b/internal/database/sqlite_open.go @@ -0,0 +1,147 @@ +package database + +import ( + "database/sql" + "fmt" + "net/url" + "time" + + _ "modernc.org/sqlite" // Pure Go SQLite driver +) + +// Every SQLite file this service opens — the main database, the +// per-webhook event databases, and the archive databases — is opened +// through OpenSQLite, so the durability settings below are properties +// of the service rather than of one call site. +// +// modernc.org/sqlite installs no busy handler and issues no pragmas of +// its own: it executes only the pragmas named in explicit `_pragma=` +// DSN parameters, and gorm.io/driver/sqlite adds none when it is +// handed an existing *sql.DB. Every setting therefore has to be +// spelled out here or it is simply not in effect. +// SQLite URI open modes. +const ( + // SQLiteModeCreate creates the database file when it is missing. + SQLiteModeCreate = "rwc" + + // SQLiteModeExisting requires the file to exist already. + SQLiteModeExisting = "rw" +) + +const ( + // SQLiteBusyTimeout is how long SQLite retries a lock conflict + // before returning SQLITE_BUSY. + // + // Under WAL a reader never blocks a writer, so the only conflict + // left is writer against writer: this process's delivery workers + // against each other, or against another process holding the write + // lock. Those clear in milliseconds. Ten seconds is far above that + // and still well inside the receiver's request budget, so an + // inbound webhook waits rather than being rejected with a 500. + SQLiteBusyTimeout = 10 * time.Second + + // sqliteMaxOpenConns bounds the connection pool for one database + // file. + // + // The pool needs a bound at all because database/sql cannot detect + // a connection left mid-transaction: modernc.org/sqlite implements + // neither driver.Validator nor driver.SessionResetter, so a + // connection whose COMMIT failed is returned to the pool with its + // transaction still open and handed out again indefinitely. That is + // what turned four `database is locked` errors into 593 + // `cannot start a transaction within a transaction` in + // https://git.eeqj.de/sneak/webhooker/issues/256. + // + // Four is above the one writer SQLite allows at a time, so reads + // still proceed while a write is in flight, and low enough that + // contention is resolved by the busy handler rather than by piling + // up connections against a lock only one of them can hold. + sqliteMaxOpenConns = 4 + + // sqliteMaxIdleConns keeps the pool warm without holding every + // connection open through an idle period. + sqliteMaxIdleConns = 2 + + // sqliteConnMaxLifetime and sqliteConnMaxIdleTime retire pooled + // connections on a schedule. With _txlock=immediate a failed + // COMMIT should no longer be reachable, but these bound the damage + // if one happens anyway: a poisoned connection is closed and + // replaced within the lifetime instead of wedging the file until + // the process restarts. + sqliteConnMaxLifetime = 5 * time.Minute + sqliteConnMaxIdleTime = time.Minute +) + +// SQLiteDSN builds the connection string for one database file. +// +// mode is the SQLite URI open mode: "rwc" to create the file when it +// is missing, "rw" to require that it already exists. +// +// Three settings carry the fix for +// https://git.eeqj.de/sneak/webhooker/issues/256 and none of them is +// optional: +// +// - journal_mode=WAL, so a reader — an operator running +// `sqlite3 .dump` over their own data — takes a snapshot +// instead of blocking every writer behind it. +// +// - busy_timeout, so a writer that does meet a lock waits for it. +// Without one SQLite gives up immediately; nothing above it +// retries. +// +// - _txlock=immediate, so every transaction takes the write lock at +// BEGIN. A deferred transaction acquires it lazily on its first +// write, and that upgrade returns SQLITE_BUSY *without* consulting +// the busy handler, because SQLite cannot block a transaction that +// may already hold a read snapshot. Such a COMMIT then fails while +// the transaction stays open on the connection. A busy timeout +// alone does not prevent this; BEGIN IMMEDIATE does, by putting +// the wait somewhere the handler applies. +// +// Note what is absent: `cache=shared`. Under a shared cache an +// in-process conflict is reported as SQLITE_LOCKED rather than +// SQLITE_BUSY, and the busy handler does not retry SQLITE_LOCKED — so +// leaving it in would have defeated the busy timeout for exactly the +// contention this service generates. Dropping it is part of the fix, +// not housekeeping. +// +// synchronous is deliberately left at SQLite's default of FULL: this +// is a webhook receiver whose one promise is that an event it answered +// 200 for is durable. +func SQLiteDSN(path, mode string) string { + q := url.Values{} + q.Set("mode", mode) + q.Set("_txlock", "immediate") + q.Add("_pragma", "journal_mode(WAL)") + q.Add( + "_pragma", + fmt.Sprintf( + "busy_timeout(%d)", + SQLiteBusyTimeout.Milliseconds(), + ), + ) + + return "file:" + path + "?" + q.Encode() +} + +// OpenSQLite opens the SQLite file at path with the service's +// durability settings and pool bounds applied. mode is the SQLite URI +// open mode ("rwc" or "rw"). +// +// The handle is returned rather than a *gorm.DB because the callers +// wrap it in gorm themselves with their own logger. +func OpenSQLite(path, mode string) (*sql.DB, error) { + sqlDB, err := sql.Open("sqlite", SQLiteDSN(path, mode)) + if err != nil { + return nil, fmt.Errorf( + "opening sqlite database %s: %w", path, err, + ) + } + + sqlDB.SetMaxOpenConns(sqliteMaxOpenConns) + sqlDB.SetMaxIdleConns(sqliteMaxIdleConns) + sqlDB.SetConnMaxLifetime(sqliteConnMaxLifetime) + sqlDB.SetConnMaxIdleTime(sqliteConnMaxIdleTime) + + return sqlDB, nil +} diff --git a/internal/database/sqlite_open_test.go b/internal/database/sqlite_open_test.go new file mode 100644 index 0000000..fcafb9a --- /dev/null +++ b/internal/database/sqlite_open_test.go @@ -0,0 +1,167 @@ +package database_test + +import ( + "context" + "path/filepath" + "strings" + "testing" + + "github.com/google/uuid" + "github.com/stretchr/testify/assert" + "github.com/stretchr/testify/require" + "gorm.io/gorm" + "sneak.berlin/go/webhooker/internal/database" +) + +// livePragma reads a pragma off a live handle. Reading the DSN back +// would prove only that the string was built; these tests assert that +// SQLite actually applied it. +func livePragma(t *testing.T, db *gorm.DB, name string) string { + t.Helper() + + var v string + + row := db.Raw("pragma " + name).Row() + require.NoError(t, row.Scan(&v)) + + return v +} + +func TestSQLiteDSNCarriesTheDurabilitySettings(t *testing.T) { + t.Parallel() + + dsn := database.SQLiteDSN( + "/var/lib/webhooker/webhooker.db", + database.SQLiteModeCreate, + ) + + assert.Contains(t, dsn, "journal_mode%28WAL%29") + assert.Contains(t, dsn, "busy_timeout%2810000%29") + assert.Contains(t, dsn, "_txlock=immediate") + assert.Contains(t, dsn, "mode=rwc") + + // cache=shared turns an in-process conflict into SQLITE_LOCKED, + // which the busy handler does not retry. It must never come back. + // See https://git.eeqj.de/sneak/webhooker/issues/256. + assert.NotContains(t, strings.ToLower(dsn), "cache=shared") +} + +// TestPerWebhookDBAppliesPragmasOnALiveHandle is the check the issue +// asks for by name: the settings are confirmed by querying the running +// database, not by inspecting the connection string. +func TestPerWebhookDBAppliesPragmasOnALiveHandle(t *testing.T) { + t.Parallel() + + mgr, lc := setupTestWebhookDBManager(t) + ctx := context.Background() + require.NoError(t, lc.Start(ctx)) + + defer func() { require.NoError(t, lc.Stop(ctx)) }() + + webhookID := uuid.New().String() + + db, err := mgr.GetDB(webhookID) + require.NoError(t, err) + + assert.Equal( + t, "wal", + strings.ToLower(livePragma(t, db, "journal_mode")), + ) + assert.Equal( + t, "10000", livePragma(t, db, "busy_timeout"), + ) +} + +func TestMainDBAppliesPragmasOnALiveHandle(t *testing.T) { + t.Parallel() + + ctx := context.Background() + dir := t.TempDir() + + sqlDB, err := database.OpenSQLite( + filepath.Join(dir, database.MainDBFileName), + database.SQLiteModeCreate, + ) + require.NoError(t, err) + + defer func() { require.NoError(t, sqlDB.Close()) }() + + var journal string + + require.NoError(t, sqlDB. + QueryRowContext(ctx, "pragma journal_mode"). + Scan(&journal)) + assert.Equal(t, "wal", strings.ToLower(journal)) + + var busy string + + require.NoError(t, sqlDB. + QueryRowContext(ctx, "pragma busy_timeout"). + Scan(&busy)) + assert.Equal(t, "10000", busy) +} + +// TestConcurrentReaderDoesNotBlockWrites is the unit-scale form of the +// reproduction in +// https://git.eeqj.de/sneak/webhooker/issues/256: an operator's +// long-held read of their own data used to make every concurrent write +// fail. Under WAL the reader takes a snapshot and the writes proceed. +func TestConcurrentReaderDoesNotBlockWrites(t *testing.T) { + t.Parallel() + + mgr, lc := setupTestWebhookDBManager(t) + ctx := context.Background() + require.NoError(t, lc.Start(ctx)) + + defer func() { require.NoError(t, lc.Stop(ctx)) }() + + webhookID := uuid.New().String() + + db, err := mgr.GetDB(webhookID) + require.NoError(t, err) + + // A second handle on the same file, holding a read transaction + // open across every write below — what `sqlite3 .dump` is. + readerSQL, err := database.OpenSQLite( + mgr.DBPath(webhookID), database.SQLiteModeExisting, + ) + require.NoError(t, err) + + defer func() { require.NoError(t, readerSQL.Close()) }() + + readerConn, err := readerSQL.Conn(ctx) + require.NoError(t, err) + + defer func() { require.NoError(t, readerConn.Close()) }() + + _, err = readerConn.ExecContext(ctx, "begin deferred") + require.NoError(t, err) + + _, err = readerConn.ExecContext( + ctx, "select count(*) from events", + ) + require.NoError(t, err) + + for range 25 { + err = db.Transaction(func(tx *gorm.DB) error { + return tx.Create(&database.Event{ + WebhookID: webhookID, + EntrypointID: uuid.New().String(), + Method: "POST", + Body: "{}", + }).Error + }) + require.NoError(t, err) + } + + _, err = readerConn.ExecContext(ctx, "commit") + require.NoError(t, err) + + var count int64 + + require.NoError( + t, + db.Model(&database.Event{}).Count(&count).Error, + ) + assert.Equal(t, int64(25), count) +} diff --git a/internal/database/webhook_db_manager.go b/internal/database/webhook_db_manager.go index a888ad5..81ca427 100644 --- a/internal/database/webhook_db_manager.go +++ b/internal/database/webhook_db_manager.go @@ -2,7 +2,6 @@ package database import ( "context" - "database/sql" "errors" "fmt" "log/slog" @@ -234,12 +233,11 @@ func (m *WebhookDBManager) openDB( webhookID string, ) (*gorm.DB, error) { path := m.dbPath(webhookID) - dbURL := fmt.Sprintf( - "file:%s?cache=shared&mode=rwc", - path, - ) - sqlDB, err := sql.Open("sqlite", dbURL) + // See sqlite_open.go: WAL, a busy timeout, immediate-transaction + // locking, and a bounded pool, all of which this file needs most — + // it is the one every delivery worker writes to concurrently. + sqlDB, err := OpenSQLite(path, SQLiteModeCreate) if err != nil { return nil, fmt.Errorf( "opening webhook database %s: %w", diff --git a/internal/delivery/engine.go b/internal/delivery/engine.go index 81bdc1f..77d8add 100644 --- a/internal/delivery/engine.go +++ b/internal/delivery/engine.go @@ -41,6 +41,26 @@ const ( // sweep runs. retrySweepInterval = 60 * time.Second + // pendingSweepMinAge is how long a delivery must have sat at + // pending before the sweep treats it as stranded rather than as + // in flight. + // + // A delivery is pending from the moment it is created until its + // outcome is written, which includes the whole time a worker + // spends on it, so the bound has to clear the longest a live + // attempt can take: httpClientTimeout plus queueing behind the + // other deliveries in front of it. Five minutes is far above + // that, and still recovers a stranded delivery in minutes rather + // than at the next restart. + pendingSweepMinAge = 5 * time.Minute + + // pendingSweepBatch bounds how many stranded pending deliveries + // one sweep of one webhook re-dispatches. The sweep runs every + // retrySweepInterval, so a larger backlog drains across + // successive sweeps instead of arriving as one burst against a + // database that was already struggling to accept writes. + pendingSweepBatch = 500 + // MaxInlineBodySize is the maximum event body size that // will be carried inline in a Task through the channel. // Bodies at or above this size are left nil and fetched @@ -634,11 +654,120 @@ func (e *Engine) recoverPendingDeliveries( "count", len(deliveries), ) + e.recoverPendingBatch( + ctx, webhookDB, webhookID, deliveries, + ) +} + +// recoverPendingBatch settles every delivery in the batch that was +// already delivered, and re-dispatches only the rest. Both the +// restart-time recovery and the periodic sweep go through it, so a +// pending delivery is treated the same however it was found. +func (e *Engine) recoverPendingBatch( + ctx context.Context, + webhookDB *gorm.DB, + webhookID string, + deliveries []database.Delivery, +) { targetMap := e.loadTargetMap(deliveries) - e.sendRecoveredDeliveries( - ctx, deliveries, webhookID, targetMap, + settled := e.reconcileDelivered( + webhookDB, webhookID, deliveries, targetMap, ) + + e.sendRecoveredDeliveries( + ctx, webhookDB, deliveries, webhookID, + targetMap, settled, + ) +} + +// reconcileDelivered finds the deliveries in a pending batch that +// already have a successful DeliveryResult, marks them delivered, and +// returns their ids so the caller does not send them a second time. +// +// This is the state the engine previously had no way to represent. A +// delivery is left pending by a failed bookkeeping write, and that +// covers two different histories: nothing was ever sent, or the send +// reached the receiver and only the status write failed. Re-sending +// was the sole option, so every stranded row produced a duplicate at +// the receiver and an event log that recorded one attempt for two +// POSTs. A successful result row distinguishes them: it is written +// before the status, so its presence means the wire I/O happened and +// was recorded, and all that is missing is the status. +// +// Deliveries whose result row itself never landed are not in the +// returned set and are re-sent, recorded as the further attempt they +// are. That is honest at-least-once delivery rather than a silent +// duplicate. +func (e *Engine) reconcileDelivered( + webhookDB *gorm.DB, + webhookID string, + deliveries []database.Delivery, + targetMap map[string]database.Target, +) map[string]struct{} { + settled := make(map[string]struct{}) + + if len(deliveries) == 0 { + return settled + } + + ids := make([]string, 0, len(deliveries)) + for i := range deliveries { + ids = append(ids, deliveries[i].ID) + } + + var deliveredIDs []string + + err := webhookDB. + Model(&database.DeliveryResult{}). + Where( + "delivery_id IN ? AND success = ?", ids, true, + ). + Distinct(). + Pluck("delivery_id", &deliveredIDs).Error + if err != nil { + // Every delivery stays out of the settled set, so the batch + // is re-sent exactly as it was before this check existed. + // That is the safe direction: a duplicate delivery beats + // declaring a delivery successful on a query that failed. + e.log.Error( + "failed to query successful delivery results; "+ + "pending deliveries will be re-sent", + "webhook_id", webhookID, + "error", err, + ) + + return settled + } + + for _, id := range deliveredIDs { + settled[id] = struct{}{} + } + + if len(settled) == 0 { + return settled + } + + e.log.Info( + "settling pending deliveries that already succeeded", + "webhook_id", webhookID, + "count", len(settled), + ) + + for i := range deliveries { + if _, ok := settled[deliveries[i].ID]; !ok { + continue + } + + e.settleStatus( + webhookDB, + &deliveries[i], + targetMap[deliveries[i].TargetID].Type, + database.DeliveryStatusDelivered, + ) + } + + return settled } func (e *Engine) retrySweep(ctx context.Context) { @@ -733,6 +862,65 @@ func (e *Engine) sweepWebhookRetries( webhookDB, webhookID, &retrying[i], ) } + + e.sweepWebhookPending(ctx, webhookDB, webhookID) +} + +// sweepWebhookPending recovers deliveries stranded at pending. +// +// A delivery is created pending and leaves that state only when its +// outcome is written, so a pending row older than the age bound is one +// whose bookkeeping write failed — the state that used to sit there +// until a restart, and then produce a duplicate at the receiver. The +// sweep gives it the same reconcile-then-dispatch treatment restart +// recovery gets, so it costs a minute rather than an operator +// noticing. +// +// The age bound is what keeps the sweep off deliveries the workers +// still hold: a delivery in flight is pending too, and re-dispatching +// one would race the worker that owns it. It is measured on updated_at +// rather than created_at because claimPending stamps that column when +// a delivery is handed out, which is what stops the next sweep, a +// minute later, from sending the same delivery again while the first +// attempt is still running. +func (e *Engine) sweepWebhookPending( + ctx context.Context, + webhookDB *gorm.DB, + webhookID string, +) { + var pending []database.Delivery + + err := webhookDB. + Where( + "status = ? AND updated_at < ?", + database.DeliveryStatusPending, + time.Now().Add(-pendingSweepMinAge), + ). + Preload("Event"). + Limit(pendingSweepBatch). + Find(&pending).Error + if err != nil { + e.log.Error( + "retry sweep: "+ + "failed to query pending deliveries", + "webhook_id", webhookID, + "error", err, + ) + + return + } + + if len(pending) == 0 { + return + } + + e.log.Info( + "retry sweep: recovering stranded pending deliveries", + "webhook_id", webhookID, + "count", len(pending), + ) + + e.recoverPendingBatch(ctx, webhookDB, webhookID, pending) } // sweepSingleRetry re-enqueues an orphaned retrying delivery @@ -839,7 +1027,7 @@ func (e *Engine) failUnretryableRetry( target.Type, ) - e.recordResult( + err := e.recordResult( webhookDB, d, e.countAttempts(webhookDB, d.ID)+1, @@ -849,6 +1037,11 @@ func (e *Engine) failUnretryableRetry( reason, 0, ) + if err != nil { + e.bookkeepingFailed(d, err) + + return + } // The type is passed rather than assigned onto d: the delivery // is loaded here without its target relation, and populating @@ -856,7 +1049,7 @@ func (e *Engine) failUnretryableRetry( // whole target row — plaintext config, which for a slack target // is the credential — into the per-webhook event database. See // https://git.eeqj.de/sneak/webhooker/issues/206. - e.updateDeliveryStatus( + e.settleStatus( webhookDB, d, target.Type, database.DeliveryStatusFailed, ) @@ -878,7 +1071,7 @@ func (e *Engine) processDelivery( "type", d.Target.Type, ) - e.updateDeliveryStatus( + e.settleStatus( webhookDB, d, d.Target.Type, database.DeliveryStatusFailed, ) @@ -910,6 +1103,14 @@ func (e *Engine) observeAttempt( // recordResult persists a DeliveryResult row describing a // single attempt. It is a cross-target helper the targets // call. +// +// It returns its error rather than swallowing it. A DeliveryResult +// row is the only record that an attempt happened at all, so a +// caller that ignored a failed write would go on to mark the +// delivery delivered — leaving the event log claiming one attempt +// for a receiver that got two. Every caller must instead stop +// advancing the delivery's status and let it stay in the +// non-terminal state it already holds; see bookkeepingFailed. func (e *Engine) recordResult( webhookDB *gorm.DB, d *database.Delivery, @@ -918,7 +1119,7 @@ func (e *Engine) recordResult( statusCode int, respBody, errMsg string, durationMs int64, -) { +) error { result := &database.DeliveryResult{ DeliveryID: d.ID, AttemptNum: attemptNum, @@ -931,12 +1132,44 @@ func (e *Engine) recordResult( err := webhookDB.Create(result).Error if err != nil { - e.log.Error( - "failed to record delivery result", - "delivery_id", d.ID, - "error", err, + return fmt.Errorf( + "recording delivery result for %s: %w", d.ID, err, ) } + + return nil +} + +// bookkeepingFailed reports that a delivery's own record of what +// happened could not be written, and deliberately writes nothing in +// response. +// +// Leaving the row alone is the whole point. A delivery is created +// pending and only ever leaves that state through +// updateDeliveryStatus, so a delivery whose bookkeeping write failed +// is still pending or retrying — the two non-terminal states, per +// DeliveryStatus.Terminal — and both are swept and recovered. Writing +// anything here would need the very database that just refused a +// write, and would be one more thing to fail; not writing cannot. +// +// The cost is honest at-least-once behaviour: a send that reached the +// receiver but whose result row did not land is attempted again, and +// recorded as the further attempt it is. What no longer happens is the +// silent duplicate — a second POST the event log denies ever +// occurred. Where the result row *did* land and only the status write +// failed, reconcileDelivered settles the row without re-sending. +func (e *Engine) bookkeepingFailed( + d *database.Delivery, err error, +) { + e.log.Error( + "delivery bookkeeping write failed; leaving delivery "+ + "in a recoverable state", + "delivery_id", d.ID, + "event_id", d.EventID, + "target_id", d.TargetID, + "status", d.Status, + "error", err, + ) } // updateDeliveryStatus persists a new status for a delivery. @@ -952,26 +1185,45 @@ func (e *Engine) recordResult( // // The counter moves only after the row is written, so a transition // the database rejected is not claimed as an outcome that happened. +// For the same reason the error is returned rather than logged and +// dropped: a delivery whose status write failed has not reached that +// status, and its caller must not act as though it had. func (e *Engine) updateDeliveryStatus( webhookDB *gorm.DB, d *database.Delivery, targetType database.TargetType, status database.DeliveryStatus, -) { +) error { err := webhookDB.Model(d). Update("status", status).Error if err != nil { - e.log.Error( - "failed to update delivery status", - "delivery_id", d.ID, - "status", status, - "error", err, + return fmt.Errorf( + "updating delivery %s to status %s: %w", + d.ID, status, err, ) - - return } e.mtr.DeliveryStatusChanged(targetType, status) + + return nil +} + +// settleStatus moves a delivery to its outcome status and reports a +// failed write through bookkeepingFailed, which leaves the row +// recoverable. It exists so the target call sites read as one +// statement rather than four lines of identical error handling. +func (e *Engine) settleStatus( + webhookDB *gorm.DB, + d *database.Delivery, + targetType database.TargetType, + status database.DeliveryStatus, +) { + err := e.updateDeliveryStatus( + webhookDB, d, targetType, status, + ) + if err != nil { + e.bookkeepingFailed(d, err) + } } func truncate(s string, maxLen int) string { @@ -1065,6 +1317,95 @@ func (e *Engine) countAttempts( return int(resultCount) } +// claimPending takes ownership of a pending delivery before it is +// re-dispatched, and reports whether the claim succeeded. +// +// The claim is a compare-and-set on the status: it takes effect only +// while the delivery is still pending, so a worker that settled the +// delivery between the query and here wins and nothing is re-sent. +// Stamping updated_at is the claim itself — the sweep selects on that +// column, so a delivery handed out now is out of the sweep's reach for +// a further pendingSweepMinAge, rather than being sent again on every +// sweep for as long as the attempt takes. +// +// A claim that cannot be written means the database is refusing +// writes, which is the condition that stranded this delivery in the +// first place. Not sending is then the right answer: the attempt +// could not be recorded either, and an unrecordable send is exactly +// the duplicate this issue is about. +func (e *Engine) claimPending( + webhookDB *gorm.DB, d *database.Delivery, +) bool { + res := webhookDB. + Model(&database.Delivery{}). + Where( + "id = ? AND status = ?", + d.ID, database.DeliveryStatusPending, + ). + UpdateColumn("updated_at", time.Now()) + if res.Error != nil { + e.log.Error( + "failed to claim pending delivery for recovery; "+ + "leaving it for the next sweep", + "delivery_id", d.ID, + "error", res.Error, + ) + + return false + } + + return res.RowsAffected == 1 +} + +// countAttemptsBatch counts the recorded attempts of every delivery +// in a batch with one grouped query, keyed by delivery id. Deliveries +// with no attempts are simply absent from the result, which reads back +// as the zero this caller wants. +// +// One query rather than one per delivery: this runs on the recovery +// path, which is a burst of writes against a database that has just +// been under enough contention to strand these rows in the first +// place. See https://git.eeqj.de/sneak/webhooker/issues/256. +func (e *Engine) countAttemptsBatch( + webhookDB *gorm.DB, deliveries []database.Delivery, +) map[string]int { + counts := make(map[string]int, len(deliveries)) + + if len(deliveries) == 0 { + return counts + } + + ids := make([]string, 0, len(deliveries)) + for i := range deliveries { + ids = append(ids, deliveries[i].ID) + } + + // One delivery id per recorded attempt, tallied here rather than + // grouped in SQL: internal/gormlog forbids (*gorm.DB).Scan, which + // a GROUP BY into a struct would need, and an attempt row per + // delivery is bounded by the target's MaxRetries. + var attemptIDs []string + + err := webhookDB. + Model(&database.DeliveryResult{}). + Where("delivery_id IN ?", ids). + Pluck("delivery_id", &attemptIDs).Error + if err != nil { + e.log.Error( + "failed to count delivery attempts for recovery", + "error", err, + ) + + return counts + } + + for _, id := range attemptIDs { + counts[id]++ + } + + return counts +} + func (e *Engine) loadEvent( webhookDB *gorm.DB, eventID string, ) (database.Event, error) { @@ -1168,12 +1509,24 @@ func (e *Engine) loadTargetMap( return targetMap } +// sendRecoveredDeliveries re-dispatches pending deliveries, skipping +// the ids in settled — those already reached their receiver and have +// been marked delivered by reconcileDelivered. func (e *Engine) sendRecoveredDeliveries( ctx context.Context, + webhookDB *gorm.DB, deliveries []database.Delivery, webhookID string, targetMap map[string]database.Target, + settled map[string]struct{}, ) { + // The attempt number continues each delivery's own history + // rather than restarting at 1. A recovered delivery may already + // have recorded attempts, and numbering the next one 1 again + // both collides in the event log and hands the retry path a + // backoff computed from the wrong attempt. + attempts := e.countAttemptsBatch(webhookDB, deliveries) + for i := range deliveries { select { case <-ctx.Done(): @@ -1181,6 +1534,10 @@ func (e *Engine) sendRecoveredDeliveries( default: } + if _, ok := settled[deliveries[i].ID]; ok { + continue + } + target, ok := targetMap[deliveries[i].TargetID] if !ok { e.log.Error( @@ -1192,9 +1549,14 @@ func (e *Engine) sendRecoveredDeliveries( continue } + if !e.claimPending(webhookDB, &deliveries[i]) { + continue + } + task := buildRecoveryTask( &deliveries[i], webhookID, - &deliveries[i].Event, &target, 1, + &deliveries[i].Event, &target, + attempts[deliveries[i].ID]+1, ) select { diff --git a/internal/delivery/engine_integration_test.go b/internal/delivery/engine_integration_test.go index 2976a2b..ba7fdc1 100644 --- a/internal/delivery/engine_integration_test.go +++ b/internal/delivery/engine_integration_test.go @@ -2,7 +2,6 @@ package delivery_test import ( "context" - "database/sql" "encoding/json" "fmt" "io" @@ -70,11 +69,12 @@ func iMainDB(t *testing.T) *gorm.DB { t.TempDir(), "main-test.db", ) - dsn := fmt.Sprintf( - "file:%s?cache=shared&mode=rwc", dbPath, + // Opened the way the service opens the main database, so these + // tests cannot pass against journal and locking settings + // production does not use. + sqlDB, err := database.OpenSQLite( + dbPath, database.SQLiteModeCreate, ) - - sqlDB, err := sql.Open("sqlite", dsn) require.NoError(t, err) t.Cleanup(func() { _ = sqlDB.Close() }) diff --git a/internal/delivery/engine_test.go b/internal/delivery/engine_test.go index 2376de7..6c2e0a2 100644 --- a/internal/delivery/engine_test.go +++ b/internal/delivery/engine_test.go @@ -3,7 +3,6 @@ package delivery_test import ( "bytes" "context" - "database/sql" "encoding/json" "fmt" "log/slog" @@ -37,11 +36,12 @@ func testWebhookDB(t *testing.T) *gorm.DB { t.TempDir(), "events-test.db", ) - dsn := fmt.Sprintf( - "file:%s?cache=shared&mode=rwc", dbPath, + // Opened the way the service opens a per-webhook database, so + // these tests cannot pass against journal and locking settings + // production does not use. + sqlDB, err := database.OpenSQLite( + dbPath, database.SQLiteModeCreate, ) - - sqlDB, err := sql.Open("sqlite", dsn) require.NoError(t, err) t.Cleanup(func() { _ = sqlDB.Close() }) diff --git a/internal/delivery/export_test.go b/internal/delivery/export_test.go index 97763f4..49a42cd 100644 --- a/internal/delivery/export_test.go +++ b/internal/delivery/export_test.go @@ -33,6 +33,11 @@ const ( // response is written against this number, so a test has to // be able to name it. ExportMaxBodyLog = maxBodyLog + + // ExportPendingSweepMinAge is how long a delivery must sit at + // pending before the sweep treats it as stranded. A test has to + // name it to age a row past the bound. + ExportPendingSweepMinAge = pendingSweepMinAge ) // ExportIsBlockedIP exposes isBlockedIP for testing. diff --git a/internal/delivery/queue_depth_gormlog_test.go b/internal/delivery/queue_depth_gormlog_test.go index e733990..8c89734 100644 --- a/internal/delivery/queue_depth_gormlog_test.go +++ b/internal/delivery/queue_depth_gormlog_test.go @@ -3,8 +3,6 @@ package delivery_test import ( "bytes" "context" - "database/sql" - "fmt" "log/slog" "net/http" "path/filepath" @@ -54,12 +52,10 @@ func (q *qdSyncBuf) String() string { func qdMainDB(t *testing.T, log *slog.Logger) *gorm.DB { t.Helper() - dsn := fmt.Sprintf( - "file:%s?cache=shared&mode=rwc", + sqlDB, err := database.OpenSQLite( filepath.Join(t.TempDir(), "main-gormlog.db"), + database.SQLiteModeCreate, ) - - sqlDB, err := sql.Open("sqlite", dsn) require.NoError(t, err) t.Cleanup(func() { _ = sqlDB.Close() }) diff --git a/internal/delivery/recovery_durability_test.go b/internal/delivery/recovery_durability_test.go new file mode 100644 index 0000000..ff8c6b1 --- /dev/null +++ b/internal/delivery/recovery_durability_test.go @@ -0,0 +1,411 @@ +package delivery_test + +import ( + "context" + "net/http" + "net/http/httptest" + "sync/atomic" + "testing" + "time" + + "github.com/google/uuid" + "github.com/stretchr/testify/assert" + "github.com/stretchr/testify/require" + "gorm.io/gorm" + "sneak.berlin/go/webhooker/internal/database" + "sneak.berlin/go/webhooker/internal/delivery" +) + +// These tests cover the delivery half of +// https://git.eeqj.de/sneak/webhooker/issues/256: a delivery that +// reached its receiver but whose bookkeeping write failed used to be +// left at pending and re-sent on the next restart, giving the receiver +// a second copy while the event log recorded one attempt. + +// rSeedResult records a DeliveryResult against a delivery, standing in +// for the attempt row the send path writes before the status. +func rSeedResult( + t *testing.T, + db *gorm.DB, + deliveryID string, + attemptNum int, + success bool, +) { + t.Helper() + + require.NoError(t, db.Create(&database.DeliveryResult{ + DeliveryID: deliveryID, + AttemptNum: attemptNum, + Success: success, + }).Error) +} + +// rAgePending backdates a delivery past the sweep's age bound, which is +// what separates a stranded delivery from one a worker still holds. +func rAgePending( + t *testing.T, db *gorm.DB, deliveryID string, +) { + t.Helper() + + old := time.Now().Add( + -2 * delivery.ExportPendingSweepMinAge, + ) + + require.NoError(t, db.Model(&database.Delivery{}). + Where("id = ?", deliveryID). + UpdateColumn("updated_at", old).Error) +} + +func TestRecoverySkipsPendingWithSuccessfulResult( + t *testing.T, +) { + t.Parallel() + + s := newISetup(t) + targetID := uuid.New().String() + + iCreateTarget(t, s.MainDB, targetID, + s.WebhookID, "already-delivered", + database.TargetTypeLog, "", 0, + ) + + event := iSeedEvent( + t, s.WebhookDB, s.WebhookID, `{"delivered":true}`, + ) + + // The delivery whose send succeeded and whose result row landed: + // only the status write failed, so it sits at pending. + done := iSeedDelivery( + t, s.WebhookDB, event.ID, targetID, + database.DeliveryStatusPending, + ) + rSeedResult(t, s.WebhookDB, done.ID, 1, true) + + // A delivery that was genuinely never attempted. + fresh := iSeedDelivery( + t, s.WebhookDB, event.ID, targetID, + database.DeliveryStatusPending, + ) + + s.Engine.ExportRecoverPendingDeliveries( + context.Background(), s.WebhookDB, s.WebhookID, + ) + + select { + case task := <-s.Engine.ExportDeliveryCh(): + assert.Equal( + t, fresh.ID, task.DeliveryID, + "only the unattempted delivery may be re-sent", + ) + case <-time.After(2 * time.Second): + t.Fatal("expected the unattempted delivery") + } + + select { + case task := <-s.Engine.ExportDeliveryCh(): + t.Fatalf( + "re-sent an already delivered delivery: %s", + task.DeliveryID, + ) + case <-time.After(200 * time.Millisecond): + } + + // It is settled rather than merely skipped: leaving it pending + // would strand it again on the next sweep. + iAssertStatus( + t, s.WebhookDB, done.ID, + database.DeliveryStatusDelivered, + ) +} + +// TestRecoveryContinuesTheAttemptNumbering pins the audit trail: a +// recovered delivery that already recorded two attempts is re-sent as +// attempt three, not as attempt one again. +func TestRecoveryContinuesTheAttemptNumbering(t *testing.T) { + t.Parallel() + + s := newISetup(t) + targetID := uuid.New().String() + + iCreateTarget(t, s.MainDB, targetID, + s.WebhookID, "numbering", + database.TargetTypeLog, "", 0, + ) + + event := iSeedEvent( + t, s.WebhookDB, s.WebhookID, `{"numbering":true}`, + ) + + d := iSeedDelivery( + t, s.WebhookDB, event.ID, targetID, + database.DeliveryStatusPending, + ) + + rSeedResult(t, s.WebhookDB, d.ID, 1, false) + rSeedResult(t, s.WebhookDB, d.ID, 2, false) + + s.Engine.ExportRecoverPendingDeliveries( + context.Background(), s.WebhookDB, s.WebhookID, + ) + + select { + case task := <-s.Engine.ExportDeliveryCh(): + assert.Equal(t, d.ID, task.DeliveryID) + assert.Equal(t, 3, task.AttemptNum) + case <-time.After(2 * time.Second): + t.Fatal("expected the delivery to be recovered") + } +} + +// TestSweepRecoversStrandedPending is the half that removes the +// restart requirement: a delivery left at pending is picked up by the +// periodic sweep. +func TestSweepRecoversStrandedPending(t *testing.T) { + t.Parallel() + + s := newISetup(t) + targetID := uuid.New().String() + + iCreateTarget(t, s.MainDB, targetID, + s.WebhookID, "stranded", + database.TargetTypeLog, "", 0, + ) + + require.NoError(t, s.MainDB.Create(&database.Webhook{ + BaseModel: database.BaseModel{ID: s.WebhookID}, + UserID: uuid.New().String(), + Name: "stranded", + }).Error) + + event := iSeedEvent( + t, s.WebhookDB, s.WebhookID, `{"stranded":true}`, + ) + + stranded := iSeedDelivery( + t, s.WebhookDB, event.ID, targetID, + database.DeliveryStatusPending, + ) + rAgePending(t, s.WebhookDB, stranded.ID) + + // A delivery a worker may still be holding: young, and therefore + // none of the sweep's business. + inFlight := iSeedDelivery( + t, s.WebhookDB, event.ID, targetID, + database.DeliveryStatusPending, + ) + + s.Engine.ExportSweepWebhookRetries( + context.Background(), s.WebhookID, + ) + + select { + case task := <-s.Engine.ExportDeliveryCh(): + assert.Equal(t, stranded.ID, task.DeliveryID) + case <-time.After(2 * time.Second): + t.Fatal("expected the stranded delivery") + } + + select { + case task := <-s.Engine.ExportDeliveryCh(): + t.Fatalf( + "swept an in-flight delivery: %s", + task.DeliveryID, + ) + case <-time.After(200 * time.Millisecond): + } + + iAssertStatus( + t, s.WebhookDB, inFlight.ID, + database.DeliveryStatusPending, + ) +} + +// TestSweepClaimsAStrandedDeliveryOnlyOnce guards the repeat the sweep +// would otherwise be: the row stays pending for as long as the attempt +// runs, and a sweep a minute later must not send it a second time. +func TestSweepClaimsAStrandedDeliveryOnlyOnce(t *testing.T) { + t.Parallel() + + s := newISetup(t) + targetID := uuid.New().String() + + iCreateTarget(t, s.MainDB, targetID, + s.WebhookID, "claimed", + database.TargetTypeLog, "", 0, + ) + + require.NoError(t, s.MainDB.Create(&database.Webhook{ + BaseModel: database.BaseModel{ID: s.WebhookID}, + UserID: uuid.New().String(), + Name: "claimed", + }).Error) + + event := iSeedEvent( + t, s.WebhookDB, s.WebhookID, `{"claimed":true}`, + ) + + d := iSeedDelivery( + t, s.WebhookDB, event.ID, targetID, + database.DeliveryStatusPending, + ) + rAgePending(t, s.WebhookDB, d.ID) + + ctx := context.Background() + + s.Engine.ExportSweepWebhookRetries(ctx, s.WebhookID) + + select { + case task := <-s.Engine.ExportDeliveryCh(): + assert.Equal(t, d.ID, task.DeliveryID) + case <-time.After(2 * time.Second): + t.Fatal("expected the stranded delivery") + } + + // The delivery is still pending — nothing has run it yet — but + // the claim must keep the next sweep off it. + iAssertStatus( + t, s.WebhookDB, d.ID, + database.DeliveryStatusPending, + ) + + s.Engine.ExportSweepWebhookRetries(ctx, s.WebhookID) + + select { + case task := <-s.Engine.ExportDeliveryCh(): + t.Fatalf( + "sent a claimed delivery again: %s", + task.DeliveryID, + ) + case <-time.After(200 * time.Millisecond): + } +} + +// TestSweepSettlesStrandedPendingWithoutResending is the sweep's own +// version of the reconcile: a stranded delivery holding a successful +// result is settled where it stands, and the receiver hears nothing. +func TestSweepSettlesStrandedPendingWithoutResending( + t *testing.T, +) { + t.Parallel() + + s := newISetup(t) + targetID := uuid.New().String() + + iCreateTarget(t, s.MainDB, targetID, + s.WebhookID, "settled", + database.TargetTypeLog, "", 0, + ) + + require.NoError(t, s.MainDB.Create(&database.Webhook{ + BaseModel: database.BaseModel{ID: s.WebhookID}, + UserID: uuid.New().String(), + Name: "settled", + }).Error) + + event := iSeedEvent( + t, s.WebhookDB, s.WebhookID, `{"settled":true}`, + ) + + d := iSeedDelivery( + t, s.WebhookDB, event.ID, targetID, + database.DeliveryStatusPending, + ) + rSeedResult(t, s.WebhookDB, d.ID, 1, true) + rAgePending(t, s.WebhookDB, d.ID) + + s.Engine.ExportSweepWebhookRetries( + context.Background(), s.WebhookID, + ) + + select { + case task := <-s.Engine.ExportDeliveryCh(): + t.Fatalf( + "re-sent a delivery that already succeeded: %s", + task.DeliveryID, + ) + case <-time.After(200 * time.Millisecond): + } + + iAssertStatus( + t, s.WebhookDB, d.ID, + database.DeliveryStatusDelivered, + ) + + var attempts int64 + + require.NoError(t, s.WebhookDB. + Model(&database.DeliveryResult{}). + Where("delivery_id = ?", d.ID). + Count(&attempts).Error) + assert.Equal( + t, int64(1), attempts, + "settling must not invent an attempt", + ) +} + +// TestFailedResultWriteLeavesDeliveryRecoverable is the rule the +// targets now follow: a bookkeeping write that fails must not advance +// the status, because pending and retrying are the states the sweeps +// recover and delivered is a claim the database refused to record. +func TestFailedResultWriteLeavesDeliveryRecoverable( + t *testing.T, +) { + t.Parallel() + + s := newISetup(t) + targetID := uuid.New().String() + + var hits atomic.Int64 + + ts := httptest.NewServer(http.HandlerFunc( + func(w http.ResponseWriter, _ *http.Request) { + hits.Add(1) + w.WriteHeader(http.StatusOK) + }, + )) + defer ts.Close() + + event := iSeedEvent( + t, s.WebhookDB, s.WebhookID, `{"unwritable":true}`, + ) + + d := iSeedDelivery( + t, s.WebhookDB, event.ID, targetID, + database.DeliveryStatusPending, + ) + + // Drop the table the attempt row goes in, so the send succeeds + // and only the bookkeeping write fails. + require.NoError( + t, + s.WebhookDB.Exec("drop table delivery_results").Error, + ) + + full := &database.Delivery{ + EventID: event.ID, + TargetID: targetID, + Status: database.DeliveryStatusPending, + Event: event, + Target: database.Target{ + Name: "unwritable", + Type: database.TargetTypeHTTP, + Config: iHTTPConfig(ts.URL), + }, + } + full.ID = d.ID + + s.Engine.ExportDeliverHTTP( + context.Background(), s.WebhookDB, full, + &delivery.Task{DeliveryID: d.ID, AttemptNum: 1}, + ) + + assert.Equal( + t, int64(1), hits.Load(), + "the send itself must still happen", + ) + + iAssertStatus( + t, s.WebhookDB, d.ID, + database.DeliveryStatusPending, + ) +} diff --git a/internal/delivery/target_database.go b/internal/delivery/target_database.go index 04ccaf6..d319551 100644 --- a/internal/delivery/target_database.go +++ b/internal/delivery/target_database.go @@ -58,12 +58,17 @@ func (t *databaseTarget) Deliver( "error", err, ) - t.eng.recordResult( + recErr := t.eng.recordResult( webhookDB, d, 1, false, 0, "", err.Error(), elapsed.Milliseconds(), ) + if recErr != nil { + t.eng.bookkeepingFailed(d, recErr) - t.eng.updateDeliveryStatus( + return + } + + t.eng.settleStatus( webhookDB, d, d.Target.Type, database.DeliveryStatusFailed, ) @@ -71,12 +76,17 @@ func (t *databaseTarget) Deliver( return } - t.eng.recordResult( + recErr := t.eng.recordResult( webhookDB, d, 1, true, 0, "", "", elapsed.Milliseconds(), ) + if recErr != nil { + t.eng.bookkeepingFailed(d, recErr) - t.eng.updateDeliveryStatus( + return + } + + t.eng.settleStatus( webhookDB, d, d.Target.Type, database.DeliveryStatusDelivered, ) diff --git a/internal/delivery/target_database_archive.go b/internal/delivery/target_database_archive.go index d179e07..0937854 100644 --- a/internal/delivery/target_database_archive.go +++ b/internal/delivery/target_database_archive.go @@ -1,7 +1,6 @@ package delivery import ( - "database/sql" "encoding/json" "errors" "fmt" @@ -12,6 +11,7 @@ import ( "gorm.io/driver/sqlite" "gorm.io/gorm" + "sneak.berlin/go/webhooker/internal/database" "sneak.berlin/go/webhooker/internal/gormlog" ) @@ -30,13 +30,13 @@ const ( // path: open the archive file, creating it if missing, so a // first write (or a write after the operator moved the file // away) recreates it. - archiveModeCreate = "rwc" + archiveModeCreate = database.SQLiteModeCreate // archiveModeExisting is the SQLite URI mode used by the idle // sweep: open read-write but never create. A sweep must never // conjure an empty archive file for a webhook that has a // database target but has never received an event. - archiveModeExisting = "rw" + archiveModeExisting = database.SQLiteModeExisting ) var ( @@ -273,9 +273,11 @@ func (w *archiveWriter) open(expiry time.Duration) error { func (w *archiveWriter) openMode( mode string, expiry time.Duration, ) error { - dbURL := fmt.Sprintf("file:%s?mode=%s", w.path, mode) - - sqlDB, err := sql.Open("sqlite", dbURL) + // Opened through database.OpenSQLite so an archive file carries + // the same WAL journaling, busy timeout, immediate-transaction + // locking, and pool bounds as every other database file. See + // internal/database/sqlite_open.go. + sqlDB, err := database.OpenSQLite(w.path, mode) if err != nil { return fmt.Errorf( "opening archive database %s: %w", w.path, err, diff --git a/internal/delivery/target_http.go b/internal/delivery/target_http.go index 93cdf3f..127c7c4 100644 --- a/internal/delivery/target_http.go +++ b/internal/delivery/target_http.go @@ -77,14 +77,19 @@ func (c *httpCore) fireAndForget( ) { c.eng.observeAttempt(d.Target.Type, res.elapsed()) - c.eng.recordResult( + err := c.eng.recordResult( webhookDB, d, 1, res.success, res.statusCode, res.respBody, res.errMsg, res.duration, ) + if err != nil { + c.eng.bookkeepingFailed(d, err) + + return + } if res.success { - c.eng.updateDeliveryStatus( + c.eng.settleStatus( webhookDB, d, d.Target.Type, database.DeliveryStatusDelivered, ) @@ -92,7 +97,7 @@ func (c *httpCore) fireAndForget( return } - c.eng.updateDeliveryStatus( + c.eng.settleStatus( webhookDB, d, d.Target.Type, database.DeliveryStatusFailed, ) @@ -122,16 +127,25 @@ func (c *httpCore) withRetry( c.eng.observeAttempt(d.Target.Type, res.elapsed()) - c.eng.recordResult( + err := c.eng.recordResult( webhookDB, d, attemptNum, res.success, res.statusCode, res.respBody, res.errMsg, res.duration, ) + if err != nil { + // The breaker still learns the outcome: it describes the + // target's health, which is unaffected by this database's. + c.recordCircuitOutcome(cb, res.success) + + c.eng.bookkeepingFailed(d, err) + + return + } if res.success { cb.RecordSuccess() - c.eng.updateDeliveryStatus( + c.eng.settleStatus( webhookDB, d, d.Target.Type, database.DeliveryStatusDelivered, ) @@ -146,6 +160,20 @@ func (c *httpCore) withRetry( ) } +// recordCircuitOutcome feeds one attempt's outcome to the target's +// circuit breaker. +func (c *httpCore) recordCircuitOutcome( + cb *CircuitBreaker, success bool, +) { + if success { + cb.RecordSuccess() + + return + } + + cb.RecordFailure() +} + func (c *httpCore) circuitBreakerBlock( webhookDB *gorm.DB, d *database.Delivery, @@ -169,7 +197,7 @@ func (c *httpCore) circuitBreakerBlock( "cooldown_remaining", remaining, ) - c.eng.updateDeliveryStatus( + c.eng.settleStatus( webhookDB, d, d.Target.Type, database.DeliveryStatusRetrying, ) @@ -189,7 +217,7 @@ func (c *httpCore) handleRetry( attemptNum int, ) { if attemptNum >= maxRetries { - c.eng.updateDeliveryStatus( + c.eng.settleStatus( webhookDB, d, d.Target.Type, database.DeliveryStatusFailed, ) @@ -197,7 +225,7 @@ func (c *httpCore) handleRetry( return } - c.eng.updateDeliveryStatus( + c.eng.settleStatus( webhookDB, d, d.Target.Type, database.DeliveryStatusRetrying, ) @@ -332,12 +360,17 @@ func (t *httpTarget) Deliver( "error", err, ) - t.eng.recordResult( + recErr := t.eng.recordResult( webhookDB, d, task.AttemptNum, false, 0, "", err.Error(), 0, ) + if recErr != nil { + t.eng.bookkeepingFailed(d, recErr) - t.eng.updateDeliveryStatus( + return + } + + t.eng.settleStatus( webhookDB, d, d.Target.Type, database.DeliveryStatusFailed, ) diff --git a/internal/delivery/target_log.go b/internal/delivery/target_log.go index 26aa7e2..096a5c7 100644 --- a/internal/delivery/target_log.go +++ b/internal/delivery/target_log.go @@ -55,12 +55,17 @@ func (t *logTarget) Deliver( t.eng.observeAttempt(d.Target.Type, elapsed) - t.eng.recordResult( + err := t.eng.recordResult( webhookDB, d, 1, true, 0, "", "", elapsed.Milliseconds(), ) + if err != nil { + t.eng.bookkeepingFailed(d, err) - t.eng.updateDeliveryStatus( + return + } + + t.eng.settleStatus( webhookDB, d, d.Target.Type, database.DeliveryStatusDelivered, ) diff --git a/internal/delivery/target_slack.go b/internal/delivery/target_slack.go index 3f855d1..f10cc15 100644 --- a/internal/delivery/target_slack.go +++ b/internal/delivery/target_slack.go @@ -95,12 +95,17 @@ func (t *slackTarget) failConfig( d *database.Delivery, err error, ) { - t.eng.recordResult( + recErr := t.eng.recordResult( webhookDB, d, 1, false, 0, "", err.Error(), 0, ) + if recErr != nil { + t.eng.bookkeepingFailed(d, recErr) - t.eng.updateDeliveryStatus( + return + } + + t.eng.settleStatus( webhookDB, d, d.Target.Type, database.DeliveryStatusFailed, ) diff --git a/internal/handlers/event_body.go b/internal/handlers/event_body.go index 3d862ff..d46b9a5 100644 --- a/internal/handlers/event_body.go +++ b/internal/handlers/event_body.go @@ -92,11 +92,10 @@ func (h *Handlers) HandleEventBodyDownload() http.HandlerFunc { // once per range. // // One consequence is worth keeping in view: the read finishes -// before the client is written to, so no read lock is held for -// the length of a slow download. These per-webhook databases -// run in SQLite's default journal mode rather than WAL, so a -// lock held that long would block the receiver from recording -// new events. +// before the client is written to, so nothing is held open for +// the length of a slow download. Under WAL a read no longer +// blocks the receiver, but it does pin the WAL against +// checkpointing, and a download can last minutes. func (h *Handlers) serveEventBody( w http.ResponseWriter, r *http.Request, diff --git a/internal/handlers/event_resubmit.go b/internal/handlers/event_resubmit.go index 0d898b5..2011da8 100644 --- a/internal/handlers/event_resubmit.go +++ b/internal/handlers/event_resubmit.go @@ -143,10 +143,10 @@ func (h *Handlers) resubmitEvent( } // Read before the write transaction is opened. The body can be up - // to the 1 MB ingest cap, and holding a read of it inside the - // transaction would extend how long the per-webhook database is - // locked against the receiver, which runs these files in - // SQLite's default journal mode rather than WAL. + // to the 1 MB ingest cap, and every transaction on these files + // takes the write lock at BEGIN (_txlock=immediate, see + // internal/database/sqlite_open.go), so reading inside it would + // hold that lock against the receiver for the length of the read. src, found, err := loadResubmitSource( webhookDB, webhook.ID, eventID.String(), )