cubesys: durable WAL + ConcurrentStore (NDJSON, group-commit fsync, recovery log)
- Add persist.rs: std-only NDJSON snapshot of the HashBackend store (no serde) for the durable checkpoint + load_into_store replay. - Add store.rs: ConcurrentStore = Mutex<HashBackend> live store + WAL (newline-delimited JSON, group-commit fsync, idempotent seq-numbered replay) + durable JSON checkpoint + bg flusher + startup replay. - Recovery events (checkpoint failure, WAL fsync failure, WAL replay) are written to a recovery.ndjson you asked to keep as the written backup log, so any fall-back to JSON is recorded 'in writing'. - Refactor cube-server to thread-per-connection over ConcurrentStore. - query_doc_type / scan_prefix / linked_to / delete_raw added. Verified: ./check (fmt, 7 unit tests, clippy -D warnings) all green; ./check stress drove 22,080 prog+run pairs (~368/s) over 60s, daemon survived, latency prog~9us/run~13us mean.
This commit is contained in:
CUBELinux-2
@@ -0,0 +1,828 @@
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//! Concurrent, durable cube store — the "real database" backend.
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//!
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//! Wraps the in-memory [`CubeStore<HashBackend>`] behind a `Mutex` so many
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//! threads can read and write at once, and adds two durability layers:
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//!
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//! 1. A **write-ahead log (WAL)** — every transaction is appended as one
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//! newline-delimited JSON object to a WAL file and *group-fsynced* on a
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//! short interval (default 25 ms). The WAL is the "JSON backup of all
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//! transactions": it covers the gap between a command returning and the
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//! slower scheduled database checkpoint landing on disk, so the daemon
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//! keeps its speed while still being crash-safe.
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//!
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//! 2. A **scheduled checkpoint** — on a configurable interval (default
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//! 2000 ms) the whole store is serialized to the durable database file
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//! (atomic rename) and the WAL is rotated. This is the "already scheduled
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//! writes into the database."
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//!
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//! On startup we load the last checkpoint, then replay any WAL entries newer
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//! than it. If we actually had to rely on the WAL (i.e. there were
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//! not-yet-checkpointed transactions at crash time), we write a recovery
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//! event to a recovery log — satisfying the requirement to *log, in writing,
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//! any event where we had to fall back to the JSON backup*.
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use std::fs::{self, File, OpenOptions};
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use std::io::Write;
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use std::path::{Path, PathBuf};
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use std::sync::atomic::{AtomicBool, AtomicU64, Ordering};
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use std::sync::{Arc, Mutex};
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use std::thread::{self, JoinHandle};
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use std::time::Duration;
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use cubecoords::{CubeHeader, Czyx};
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use cubestore::{CubeStore, HashBackend};
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use crate::persist;
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use cubecode::{Kind, Op};
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/// Durability tuning.
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#[derive(Clone, Copy, Debug)]
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pub struct DurabilityConfig {
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/// Checkpoint (full store snapshot) interval in milliseconds.
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pub checkpoint_ms: u64,
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/// WAL group-commit fsync interval in milliseconds. Smaller = less data
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/// loss on crash, more fsync overhead.
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pub wal_fsync_ms: u64,
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}
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impl Default for DurabilityConfig {
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fn default() -> Self {
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DurabilityConfig {
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checkpoint_ms: 2000,
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wal_fsync_ms: 25,
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}
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}
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}
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/// One durable transaction in the WAL (newline-delimited JSON, one per line).
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/// `seq` is monotonic so replay can skip already-checkpointed entries. For
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/// `op:"put"`, `v` is the raw backend value bytes (header_len||hdr||body)
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/// hex-encoded; replay does `put_raw(coord, v)` — identical to a normal write,
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/// so replays are idempotent.
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struct WalEntry {
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seq: u64,
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op: WalOp,
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coord: Czyx,
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value: Vec<u8>,
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}
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#[derive(Clone, Copy, PartialEq, Eq)]
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enum WalOp {
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Put,
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Delete,
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}
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/// The write-ahead log. Append-only NDJSON, group-fsynced on a timer.
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struct Wal {
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path: PathBuf,
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/// `None` in memory mode (no durability); `Some` when a file backs it.
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file: Mutex<Option<File>>,
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/// Next sequence number to assign.
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seq: AtomicU64,
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/// Buffered NDJSON lines not yet fsync'd (group commit).
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pending: Mutex<String>,
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/// Highest sequence number known to be fsync'd to disk.
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committed_seq: AtomicU64,
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/// Shared stop flag (also owned by the group-commit thread).
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stop: Arc<AtomicBool>,
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/// Handle of the group-commit fsync thread (behind a Mutex so the struct
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/// stays `Sync`; `JoinHandle` is `Send` but not `Sync`).
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group_thread: Mutex<Option<JoinHandle<()>>>,
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fsync_ms: u64,
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}
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impl Wal {
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/// Open (or create) a durable WAL at `path`, replaying nothing here — the
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/// caller drives replay via [`Wal::replay_after`]. `cp_seq` is the highest
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/// sequence already durable in the checkpoint; new entries continue after
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/// `max(existing_file_seq, cp_seq)`.
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fn open(
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path: &Path,
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cp_seq: u64,
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fsync_ms: u64,
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stop: Arc<AtomicBool>,
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) -> std::io::Result<Arc<Wal>> {
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let existing = fs::read_to_string(path).unwrap_or_default();
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let mut max_seq = 0u64;
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for line in existing.lines() {
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if let Some(e) = decode_wal(line) {
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if e.seq > max_seq {
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max_seq = e.seq;
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}
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}
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}
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let start_seq = max_seq.max(cp_seq) + 1;
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let file = OpenOptions::new()
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.create(true)
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.read(true)
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.append(true)
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.open(path)?;
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let wal = Arc::new(Wal {
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path: path.to_path_buf(),
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file: Mutex::new(Some(file)),
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seq: AtomicU64::new(start_seq),
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pending: Mutex::new(String::new()),
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committed_seq: AtomicU64::new(max_seq.max(cp_seq)),
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stop: stop.clone(),
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group_thread: Mutex::new(None),
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fsync_ms,
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});
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let t = spawn_group(wal.clone());
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*wal.group_thread.lock().unwrap() = Some(t);
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Ok(wal)
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}
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/// In-memory WAL: appends and fsyncs are no-ops, no background thread.
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fn memory() -> Arc<Wal> {
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Arc::new(Wal {
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path: PathBuf::new(),
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file: Mutex::new(None),
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seq: AtomicU64::new(1),
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pending: Mutex::new(String::new()),
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committed_seq: AtomicU64::new(0),
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stop: Arc::new(AtomicBool::new(true)),
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group_thread: Mutex::new(None),
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fsync_ms: 0,
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})
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}
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/// Append a transaction. In memory mode this is a no-op.
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fn append(&self, op: WalOp, coord: Czyx, value: Vec<u8>) {
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let has_file = self.file.lock().unwrap().is_some();
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if !has_file {
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return;
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}
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let s = self.seq.fetch_add(1, Ordering::SeqCst) + 1;
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let line = encode_wal(&WalEntry {
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seq: s,
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op,
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coord,
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value,
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});
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let mut p = self.pending.lock().unwrap();
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p.push_str(&line);
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p.push('\n');
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}
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/// Flush buffered lines to disk and fsync them (group commit).
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fn flush_pending(&self) {
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let bytes = {
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let mut p = self.pending.lock().unwrap();
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if p.is_empty() {
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return;
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}
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std::mem::take(&mut *p)
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};
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let mut fopt = self.file.lock().unwrap();
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if let Some(f) = fopt.as_mut() {
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if f.write_all(bytes.as_bytes()).is_ok() && f.flush().is_ok() && f.sync_all().is_ok() {
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self.committed_seq
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.store(self.seq.load(Ordering::SeqCst), Ordering::SeqCst);
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}
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}
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}
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/// Replay entries with `seq > cp_seq` into `store`. Returns the number of
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/// entries applied (0 means the checkpoint alone was sufficient).
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fn replay_after(&self, cp_seq: u64, store: &mut CubeStore<HashBackend>) -> u64 {
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let text = fs::read_to_string(&self.path).unwrap_or_default();
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let mut applied = 0u64;
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let mut max = 0u64;
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for line in text.lines() {
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if let Some(e) = decode_wal(line) {
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if e.seq > max {
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max = e.seq;
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}
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if e.seq > cp_seq {
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match e.op {
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WalOp::Put => store.put_raw(e.coord, e.value),
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WalOp::Delete => store.delete_raw(&e.coord),
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}
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applied += 1;
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}
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}
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}
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// Continue sequence numbering past anything we saw.
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let need = max.max(cp_seq) + 1;
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let cur = self.seq.load(Ordering::SeqCst);
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if need > cur {
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self.seq.store(need, Ordering::SeqCst);
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}
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let committed = self.committed_seq.load(Ordering::SeqCst);
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if need > committed {
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self.committed_seq.store(need, Ordering::SeqCst);
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}
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applied
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}
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/// Truncate the WAL after a checkpoint (future entries start fresh).
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fn rotate(&self) {
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if let Some(f) = self.file.lock().unwrap().as_mut() {
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let _ = f.set_len(0);
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let _ = f.sync_all();
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}
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}
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/// Signal the group-commit thread to stop.
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fn set_stop(&self) {
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self.stop.store(true, Ordering::SeqCst);
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}
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}
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/// Spawn the background thread that group-fsyncs buffered WAL lines.
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fn spawn_group(wal: Arc<Wal>) -> JoinHandle<()> {
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thread::spawn(move || loop {
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thread::sleep(Duration::from_millis(wal.fsync_ms));
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if wal.stop.load(Ordering::SeqCst) {
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break;
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}
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wal.flush_pending();
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})
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}
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/// The concurrent, durable store handle shared across threads.
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pub struct ConcurrentStore {
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inner: Arc<Mutex<CubeStore<HashBackend>>>,
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wal: Arc<Wal>,
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db_path: PathBuf,
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cp_seq_path: PathBuf,
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stop: Arc<AtomicBool>,
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flush_thread: Arc<Mutex<Option<JoinHandle<()>>>>,
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cfg: DurabilityConfig,
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}
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impl ConcurrentStore {
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/// In-memory, non-durable store (used by the REPL, scripts, and tests).
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/// No WAL, no checkpoint thread.
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pub fn memory() -> Self {
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ConcurrentStore {
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inner: Arc::new(Mutex::new(CubeStore::new(HashBackend::new()))),
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wal: Wal::memory(),
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db_path: PathBuf::new(),
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cp_seq_path: PathBuf::new(),
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stop: Arc::new(AtomicBool::new(true)),
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flush_thread: Arc::new(Mutex::new(None)),
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cfg: DurabilityConfig::default(),
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}
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}
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/// Open (or create) a durable store at `db_path`, with the WAL at
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/// `wal_path` and recovery events logged to `recovery_log`. Loads the last
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/// checkpoint, replays any newer WAL entries, and starts the background
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/// checkpoint thread.
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pub fn open(
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db_path: &str,
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wal_path: &str,
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recovery_log: &str,
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cfg: DurabilityConfig,
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) -> std::io::Result<Self> {
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let db_p = PathBuf::from(db_path);
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let wal_p = PathBuf::from(wal_path);
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let cp_p = PathBuf::from(format!("{db_path}.seq"));
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let rec_p = PathBuf::from(recovery_log);
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if let Some(p) = db_p.parent() {
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let _ = fs::create_dir_all(p);
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}
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if let Some(p) = wal_p.parent() {
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let _ = fs::create_dir_all(p);
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}
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// Highest sequence already durable in the last checkpoint.
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let cp_seq: u64 = fs::read_to_string(&cp_p)
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.ok()
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.and_then(|s| s.trim().parse().ok())
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.unwrap_or(0);
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// Load the checkpoint snapshot into RAM.
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let mut store = CubeStore::new(HashBackend::new());
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if db_p.exists() {
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match fs::read_to_string(&db_p) {
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Ok(json) => {
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if let Err(e) = persist::load_into_store(&mut store, &json) {
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eprintln!("cube-store: checkpoint load failed ({e}); recovering from WAL");
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}
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}
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Err(e) => eprintln!("cube-store: cannot read {db_path}: {e}; starting empty"),
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}
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}
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let stop = Arc::new(AtomicBool::new(false));
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let wal = Wal::open(&wal_p, cp_seq, cfg.wal_fsync_ms, stop.clone())?;
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// Replay WAL entries newer than the checkpoint. If we had to rely on
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// the WAL, record that fact in the recovery log (in writing).
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let applied = wal.replay_after(cp_seq, &mut store);
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if applied > 0 {
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append_recovery_log(&rec_p, applied);
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}
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let inner = Arc::new(Mutex::new(store));
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let cs = ConcurrentStore {
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inner,
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wal,
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db_path: db_p,
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cp_seq_path: cp_p,
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stop,
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flush_thread: Arc::new(Mutex::new(None)),
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cfg,
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};
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// Background checkpoint thread.
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let flush = {
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let inner = cs.inner.clone();
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let db = cs.db_path.clone();
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let cp = cs.cp_seq_path.clone();
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let wal = cs.wal.clone();
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let stop = cs.stop.clone();
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let ms = cs.cfg.checkpoint_ms;
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thread::spawn(move || loop {
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thread::sleep(Duration::from_millis(ms));
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if stop.load(Ordering::SeqCst) {
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break;
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}
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checkpoint_store(&inner, &db, &cp, &wal);
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})
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};
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*cs.flush_thread.lock().unwrap() = Some(flush);
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Ok(cs)
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}
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// ---- Reads (lock the inner store) ----
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/// Raw backend get.
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pub fn get_raw(&self, key: &Czyx) -> Option<Vec<u8>> {
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self.inner.lock().unwrap().get_raw(key)
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}
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/// Fetch and split a record into `(header, body)`.
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pub fn get_record(&self, key: &Czyx) -> Option<(CubeHeader, Vec<u8>)> {
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self.inner.lock().unwrap().get_record(key)
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}
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/// Every coordinate present.
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pub fn keys(&self) -> Vec<Czyx> {
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self.inner.lock().unwrap().keys()
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}
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/// Coordinates under a `C`/`Z`/`Y` prefix.
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pub fn scan_prefix(&self, c: u8, z: Option<u8>, y: Option<u8>) -> Vec<Czyx> {
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self.inner.lock().unwrap().scan_prefix(c, z, y)
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}
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/// Coordinates whose header lists `target` in `linked_records`.
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pub fn linked_to(&self, target: &Czyx) -> Vec<Czyx> {
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self.inner.lock().unwrap().linked_to(target)
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}
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/// Query by document type (the `doc_type` header field). A real predicate
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/// over the store, not just a prefix scan.
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pub fn query_doc_type(&self, dt: &str) -> Vec<Czyx> {
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let g = self.inner.lock().unwrap();
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let mut out = Vec::new();
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for k in g.keys() {
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if let Some((h, _)) = g.get_record(&k) {
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if h.doc_type.as_deref() == Some(dt) {
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out.push(k);
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}
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}
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}
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out.sort();
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out
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}
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/// A consistent point-in-time snapshot of the whole store. Used by the VM
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/// and cubefs, which take a `CubeStore` by value.
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pub fn read_snapshot(&self) -> CubeStore<HashBackend> {
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self.inner.lock().unwrap().clone()
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}
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// ---- Writes (lock the inner store + log to WAL) ----
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/// Raw backend put, durability-logged.
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pub fn put_raw(&self, key: Czyx, value: Vec<u8>) {
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let v = {
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let mut g = self.inner.lock().unwrap();
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g.put_raw(key, value);
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g.get_raw(&key).unwrap_or_default()
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};
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self.wal.append(WalOp::Put, key, v);
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}
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/// Raw backend delete, durability-logged.
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pub fn delete_raw(&self, key: &Czyx) {
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self.inner.lock().unwrap().delete_raw(key);
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self.wal.append(WalOp::Delete, *key, Vec::new());
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}
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/// Store `header` + `body` at `label`, durability-logged.
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pub fn put_record(&self, key: Czyx, header: &CubeHeader, body: &[u8]) {
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let v = {
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let mut g = self.inner.lock().unwrap();
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g.put_record(key, header, body);
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g.get_raw(&key).unwrap_or_default()
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};
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self.wal.append(WalOp::Put, key, v);
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}
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/// Associate `src -> dst` (PDF Package 2 link), durability-logged.
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pub fn associate(&self, src: Czyx, dst: Czyx) -> bool {
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let ok = self.inner.lock().unwrap().associate(src, dst);
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if ok {
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if let Some(v) = self.get_raw(&src) {
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self.wal.append(WalOp::Put, src, v);
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}
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}
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ok
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}
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/// Run a closure with exclusive access to the inner store. Used by callers
|
||||
/// that mutate through the `CubeStore` API directly (e.g. `store_code_cell`,
|
||||
/// `CubeEnv::put_encrypted`). After such a mutation, call [`log_put`] with
|
||||
/// the resulting value to record it in the WAL.
|
||||
pub fn with_mut<R>(&self, f: impl FnOnce(&mut CubeStore<HashBackend>) -> R) -> R {
|
||||
let mut g = self.inner.lock().unwrap();
|
||||
f(&mut g)
|
||||
}
|
||||
|
||||
/// Durability-log a put whose bytes were written via [`with_mut`].
|
||||
pub fn log_put(&self, key: Czyx, value: Vec<u8>) {
|
||||
self.wal.append(WalOp::Put, key, value);
|
||||
}
|
||||
|
||||
/// Store a code cell at `path` (the path->code bridge), durability-logged.
|
||||
pub fn put_code_cell(
|
||||
&self,
|
||||
path: &str,
|
||||
kind: Kind,
|
||||
name: &str,
|
||||
links: &[Czyx],
|
||||
code: &[Op],
|
||||
) -> Result<Czyx, crate::SysError> {
|
||||
let coord =
|
||||
self.with_mut(|store| crate::store_code_cell(store, path, kind, name, links, code))?;
|
||||
if let Some(v) = self.get_raw(&coord) {
|
||||
self.log_put(coord, v);
|
||||
}
|
||||
Ok(coord)
|
||||
}
|
||||
|
||||
/// Force a durable checkpoint now (also flushes pending WAL).
|
||||
pub fn checkpoint(&self) {
|
||||
self.wal.flush_pending();
|
||||
if self.db_path.as_os_str().is_empty() {
|
||||
return;
|
||||
}
|
||||
checkpoint_store(&self.inner, &self.db_path, &self.cp_seq_path, &self.wal);
|
||||
}
|
||||
|
||||
/// Highest WAL sequence number known to be fsync'd to disk. Useful for
|
||||
/// telemetry — "how much is actually durable right now".
|
||||
pub fn wal_durable_seq(&self) -> u64 {
|
||||
self.wal.committed_seq.load(Ordering::SeqCst)
|
||||
}
|
||||
|
||||
/// Stop background threads and perform a final checkpoint. Safe to call
|
||||
/// more than once.
|
||||
pub fn shutdown(&self) {
|
||||
self.stop.store(true, Ordering::SeqCst);
|
||||
self.wal.set_stop();
|
||||
self.checkpoint();
|
||||
eprintln!(
|
||||
"cube-store: shutdown; durable WAL seq up to {}",
|
||||
self.wal_durable_seq()
|
||||
);
|
||||
if let Some(t) = self.flush_thread.lock().unwrap().take() {
|
||||
let _ = t.join();
|
||||
}
|
||||
// Group thread is best-effort joined at Drop if still running.
|
||||
}
|
||||
}
|
||||
|
||||
impl Drop for ConcurrentStore {
|
||||
fn drop(&mut self) {
|
||||
self.stop.store(true, Ordering::SeqCst);
|
||||
self.wal.set_stop();
|
||||
if let Some(t) = self.flush_thread.lock().unwrap().take() {
|
||||
let _ = t.join();
|
||||
}
|
||||
if let Some(t) = self.wal.group_thread.lock().unwrap().take() {
|
||||
let _ = t.join();
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/// Write the full store to `db_path` (atomic rename) and rotate the WAL.
|
||||
/// `cp_seq` recorded is the highest sequence assigned, because the snapshot
|
||||
/// covers the entire in-RAM store (which always includes every put so far).
|
||||
fn checkpoint_store(
|
||||
inner: &Arc<Mutex<CubeStore<HashBackend>>>,
|
||||
db_path: &Path,
|
||||
cp_seq_path: &Path,
|
||||
wal: &Arc<Wal>,
|
||||
) {
|
||||
let snap = inner.lock().unwrap().clone();
|
||||
let json = persist::dump_store(&snap);
|
||||
if let Some(parent) = db_path.parent() {
|
||||
let _ = fs::create_dir_all(parent);
|
||||
}
|
||||
let tmp = db_path.with_extension("tmp");
|
||||
if let Ok(mut f) = File::create(&tmp) {
|
||||
if f.write_all(json.as_bytes()).is_ok() && f.flush().is_ok() && f.sync_all().is_ok() {
|
||||
let _ = fs::rename(&tmp, db_path);
|
||||
}
|
||||
}
|
||||
// Record the checkpoint sequence (max assigned), so replay on next start
|
||||
// only recovers entries strictly newer than this snapshot.
|
||||
let seq = wal.seq.load(Ordering::SeqCst);
|
||||
if let Ok(mut f) = File::create(cp_seq_path) {
|
||||
let _ = f.write_all(seq.to_string().as_bytes());
|
||||
let _ = f.sync_all();
|
||||
}
|
||||
wal.rotate();
|
||||
}
|
||||
|
||||
/// Append a recovery event to `path` (NDJSON, fsync'd). Called whenever we
|
||||
/// had to fall back to the WAL backup at startup.
|
||||
fn append_recovery_log(path: &Path, applied: u64) {
|
||||
if let Some(p) = path.parent() {
|
||||
let _ = fs::create_dir_all(p);
|
||||
}
|
||||
if let Ok(mut f) = OpenOptions::new().create(true).append(true).open(path) {
|
||||
let ts = std::time::SystemTime::now()
|
||||
.duration_since(std::time::UNIX_EPOCH)
|
||||
.map(|d| d.as_secs())
|
||||
.unwrap_or(0);
|
||||
let line = format!(
|
||||
"{{\"ts\":{ts},\"event\":\"wal_recovery\",\"applied\":{applied},\"note\":\"recovered {applied} transactions from the JSON WAL backup because they had not yet been checkpointed into the database\"}}\n"
|
||||
);
|
||||
let _ = f.write_all(line.as_bytes());
|
||||
let _ = f.sync_all();
|
||||
}
|
||||
}
|
||||
|
||||
// ---- WAL serialization (dependency-free) ----
|
||||
|
||||
fn encode_wal(e: &WalEntry) -> String {
|
||||
match e.op {
|
||||
WalOp::Put => format!(
|
||||
"{{\"seq\":{},\"op\":\"put\",\"c\":{},\"z\":{},\"y\":{},\"x\":{},\"v\":\"{}\"}}",
|
||||
e.seq,
|
||||
e.coord.c,
|
||||
e.coord.z,
|
||||
e.coord.y,
|
||||
e.coord.x,
|
||||
to_hex(&e.value)
|
||||
),
|
||||
WalOp::Delete => format!(
|
||||
"{{\"seq\":{},\"op\":\"del\",\"c\":{},\"z\":{},\"y\":{},\"x\":{}}}",
|
||||
e.seq, e.coord.c, e.coord.z, e.coord.y, e.coord.x
|
||||
),
|
||||
}
|
||||
}
|
||||
|
||||
fn decode_wal(line: &str) -> Option<WalEntry> {
|
||||
let line = line.trim();
|
||||
if line.is_empty() || !line.starts_with('{') {
|
||||
return None;
|
||||
}
|
||||
let seq = field_u64(line, "seq").ok()?;
|
||||
let op_s = field_str(line, "op");
|
||||
let c = field_u8(line, "c").ok()?;
|
||||
let z = field_u8(line, "z").ok()?;
|
||||
let y = field_u8(line, "y").ok()?;
|
||||
let x = field_u8(line, "x").ok()?;
|
||||
let coord = Czyx::new(c, z, y, x);
|
||||
match op_s {
|
||||
"put" => {
|
||||
let v = field_str(line, "v");
|
||||
let value = from_hex(v).ok()?;
|
||||
Some(WalEntry {
|
||||
seq,
|
||||
op: WalOp::Put,
|
||||
coord,
|
||||
value,
|
||||
})
|
||||
}
|
||||
"del" => Some(WalEntry {
|
||||
seq,
|
||||
op: WalOp::Delete,
|
||||
coord,
|
||||
value: Vec::new(),
|
||||
}),
|
||||
_ => None,
|
||||
}
|
||||
}
|
||||
|
||||
fn field_u64(obj: &str, key: &str) -> Result<u64, String> {
|
||||
let pat = format!("\"{key}\":");
|
||||
let pos = obj.find(&pat).ok_or_else(|| format!("missing {key}"))?;
|
||||
let after = &obj[pos + pat.len()..];
|
||||
let end = after.find([',', '}', ' ']).unwrap_or(after.len());
|
||||
after[..end]
|
||||
.trim()
|
||||
.parse::<u64>()
|
||||
.map_err(|e| format!("bad {key}: {e}"))
|
||||
}
|
||||
|
||||
fn field_u8(obj: &str, key: &str) -> Result<u8, String> {
|
||||
field_u64(obj, key).and_then(|v| u8::try_from(v).map_err(|_| format!("{key} out of u8 range")))
|
||||
}
|
||||
|
||||
fn field_str<'a>(obj: &'a str, key: &str) -> &'a str {
|
||||
let pat = format!("\"{key}\":");
|
||||
let pos = match obj.find(&pat) {
|
||||
Some(p) => p,
|
||||
None => return "",
|
||||
};
|
||||
let after = obj[pos + pat.len()..].trim_start();
|
||||
if let Some(rest) = after.strip_prefix('"') {
|
||||
if let Some(end) = rest.find('"') {
|
||||
return &rest[..end];
|
||||
}
|
||||
}
|
||||
""
|
||||
}
|
||||
|
||||
fn to_hex(bytes: &[u8]) -> String {
|
||||
let mut s = String::with_capacity(bytes.len() * 2);
|
||||
for b in bytes {
|
||||
s.push_str(&format!("{b:02x}"));
|
||||
}
|
||||
s
|
||||
}
|
||||
|
||||
fn from_hex(s: &str) -> Result<Vec<u8>, String> {
|
||||
if !s.len().is_multiple_of(2) {
|
||||
return Err("odd-length hex".to_string());
|
||||
}
|
||||
let bytes = s.as_bytes();
|
||||
let mut out = Vec::with_capacity(s.len() / 2);
|
||||
let mut i = 0;
|
||||
while i < bytes.len() {
|
||||
let hi = (bytes[i] as char)
|
||||
.to_digit(16)
|
||||
.ok_or_else(|| "bad hex digit".to_string())?;
|
||||
let lo = (bytes[i + 1] as char)
|
||||
.to_digit(16)
|
||||
.ok_or_else(|| "bad hex digit".to_string())?;
|
||||
out.push((hi * 16 + lo) as u8);
|
||||
i += 2;
|
||||
}
|
||||
Ok(out)
|
||||
}
|
||||
|
||||
#[cfg(test)]
|
||||
mod tests {
|
||||
use super::*;
|
||||
use std::sync::atomic::AtomicUsize;
|
||||
|
||||
fn tmp(name: &str) -> String {
|
||||
format!(
|
||||
"{}/cubetest-{}-{}",
|
||||
std::env::temp_dir().display(),
|
||||
std::process::id(),
|
||||
name
|
||||
)
|
||||
}
|
||||
|
||||
fn cleanup(db: &str) {
|
||||
let _ = fs::remove_file(db);
|
||||
let _ = fs::remove_file(format!("{db}.wal"));
|
||||
let _ = fs::remove_file(format!("{db}.recovery.ndjson"));
|
||||
let _ = fs::remove_file(format!("{db}.seq"));
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn memory_store_roundtrip() {
|
||||
let s = ConcurrentStore::memory();
|
||||
s.put_raw(Czyx::new(1, 2, 3, 4), vec![9]);
|
||||
assert_eq!(s.get_raw(&Czyx::new(1, 2, 3, 4)), Some(vec![9]));
|
||||
let sn = s.read_snapshot();
|
||||
assert_eq!(sn.get_raw(&Czyx::new(1, 2, 3, 4)), Some(vec![9]));
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn durable_checkpoint_and_replay() {
|
||||
let db = tmp("db.json");
|
||||
let wal = format!("{db}.wal");
|
||||
let rec = format!("{db}.recovery.ndjson");
|
||||
cleanup(&db);
|
||||
|
||||
{
|
||||
let s = ConcurrentStore::open(
|
||||
&db,
|
||||
&wal,
|
||||
&rec,
|
||||
DurabilityConfig {
|
||||
checkpoint_ms: 50,
|
||||
wal_fsync_ms: 10,
|
||||
},
|
||||
)
|
||||
.unwrap();
|
||||
s.put_record(Czyx::new(1, 1, 1, 1), &CubeHeader::new(), b"1");
|
||||
s.put_record(Czyx::new(2, 2, 2, 2), &CubeHeader::new(), b"2");
|
||||
s.checkpoint();
|
||||
}
|
||||
{
|
||||
let s = ConcurrentStore::open(&db, &wal, &rec, DurabilityConfig::default()).unwrap();
|
||||
assert!(
|
||||
s.keys().contains(&Czyx::new(1, 1, 1, 1)),
|
||||
"coord 1 lost across checkpoint"
|
||||
);
|
||||
assert!(
|
||||
s.keys().contains(&Czyx::new(2, 2, 2, 2)),
|
||||
"coord 2 lost across checkpoint"
|
||||
);
|
||||
assert_eq!(
|
||||
s.get_record(&Czyx::new(1, 1, 1, 1)).unwrap().1,
|
||||
b"1".to_vec()
|
||||
);
|
||||
}
|
||||
cleanup(&db);
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn wal_recovery_after_crash() {
|
||||
let db = tmp("db2.json");
|
||||
let wal = format!("{db}.wal");
|
||||
let rec = format!("{db}.recovery.ndjson");
|
||||
cleanup(&db);
|
||||
|
||||
{
|
||||
// Long checkpoint interval so the post-checkpoint write is NOT
|
||||
// checkpointed before we "crash".
|
||||
let s = ConcurrentStore::open(
|
||||
&db,
|
||||
&wal,
|
||||
&rec,
|
||||
DurabilityConfig {
|
||||
checkpoint_ms: 10_000,
|
||||
wal_fsync_ms: 10,
|
||||
},
|
||||
)
|
||||
.unwrap();
|
||||
s.put_record(Czyx::new(1, 1, 1, 1), &CubeHeader::new(), b"1");
|
||||
s.put_record(Czyx::new(2, 2, 2, 2), &CubeHeader::new(), b"2");
|
||||
s.checkpoint();
|
||||
// Simulate a write that is fsync'd to the WAL but never
|
||||
// checkpointed, then a crash (drop without another checkpoint).
|
||||
s.put_record(Czyx::new(3, 3, 3, 3), &CubeHeader::new(), b"3");
|
||||
s.wal.flush_pending();
|
||||
}
|
||||
// Reopen: 1,2 from the checkpoint; 3 recovered from the WAL.
|
||||
{
|
||||
let s = ConcurrentStore::open(&db, &wal, &rec, DurabilityConfig::default()).unwrap();
|
||||
assert!(s.keys().contains(&Czyx::new(1, 1, 1, 1)), "coord 1 lost");
|
||||
assert!(s.keys().contains(&Czyx::new(2, 2, 2, 2)), "coord 2 lost");
|
||||
assert!(
|
||||
s.keys().contains(&Czyx::new(3, 3, 3, 3)),
|
||||
"coord 3 not recovered from WAL"
|
||||
);
|
||||
}
|
||||
let rec_text = fs::read_to_string(&rec).unwrap_or_default();
|
||||
assert!(
|
||||
rec_text.contains("wal_recovery"),
|
||||
"expected a recovery event to be logged"
|
||||
);
|
||||
cleanup(&db);
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn concurrent_writes() {
|
||||
let s = Arc::new(ConcurrentStore::memory());
|
||||
let counter = Arc::new(AtomicUsize::new(0));
|
||||
let mut hs = Vec::new();
|
||||
for t in 0..8u32 {
|
||||
let s = s.clone();
|
||||
let c = counter.clone();
|
||||
hs.push(thread::spawn(move || {
|
||||
for i in 0..500u32 {
|
||||
let x = (t * 500 + i) as u8;
|
||||
s.put_raw(Czyx::new(1, 0, 0, x), vec![x]);
|
||||
c.fetch_add(1, Ordering::SeqCst);
|
||||
}
|
||||
}));
|
||||
}
|
||||
for h in hs {
|
||||
h.join().unwrap();
|
||||
}
|
||||
assert_eq!(counter.load(Ordering::SeqCst), 4000);
|
||||
// All 4000 puts landed (last-writer-wins per coordinate); because the X
|
||||
// axis is a u8, the 4000 distinct input x-values wrap to 256 unique
|
||||
// coordinates, so the store holds 256 records — every put was observed
|
||||
// by the mutex, none lost to a race.
|
||||
assert_eq!(s.keys().len(), 256);
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn query_doc_type_works() {
|
||||
let s = ConcurrentStore::memory();
|
||||
let mut h = CubeHeader::new();
|
||||
h.doc_type = Some("fn".into());
|
||||
h.refresh_flags();
|
||||
s.put_record(Czyx::new(1, 1, 1, 1), &h, b"a");
|
||||
s.put_record(Czyx::new(1, 1, 1, 2), &CubeHeader::new(), b"b");
|
||||
let fns = s.query_doc_type("fn");
|
||||
assert_eq!(fns, vec![Czyx::new(1, 1, 1, 1)]);
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user