nostr-rs-relay/src/db.rs
2022-02-12 09:58:42 -06:00

519 lines
20 KiB
Rust

//! Event persistence and querying
use crate::config::SETTINGS;
use crate::error::Error;
use crate::error::Result;
use crate::event::Event;
use crate::hexrange::hex_range;
use crate::hexrange::HexSearch;
use crate::nip05;
use crate::schema::{upgrade_db, STARTUP_SQL};
use crate::subscription::Subscription;
use crate::utils::is_hex;
use governor::clock::Clock;
use governor::{Quota, RateLimiter};
use hex;
use log::*;
use r2d2;
use r2d2_sqlite::SqliteConnectionManager;
use rusqlite::params;
use rusqlite::types::ToSql;
use rusqlite::Connection;
use rusqlite::OpenFlags;
use std::path::Path;
use std::thread;
use std::time::Duration;
use std::time::Instant;
use tokio::task;
pub type SqlitePool = r2d2::Pool<r2d2_sqlite::SqliteConnectionManager>;
pub type PooledConnection = r2d2::PooledConnection<r2d2_sqlite::SqliteConnectionManager>;
/// Database file
pub const DB_FILE: &str = "nostr.db";
/// Build a database connection pool.
pub fn build_pool(
name: &str,
flags: OpenFlags,
min_size: u32,
max_size: u32,
wait_for_db: bool,
) -> SqlitePool {
let settings = SETTINGS.read().unwrap();
let db_dir = &settings.database.data_directory;
let full_path = Path::new(db_dir).join(DB_FILE);
// small hack; if the database doesn't exist yet, that means the
// writer thread hasn't finished. Give it a chance to work. This
// is only an issue with the first time we run.
while !full_path.exists() && wait_for_db {
debug!("Database reader pool is waiting on the database to be created...");
thread::sleep(Duration::from_millis(500));
}
let manager = SqliteConnectionManager::file(&full_path)
.with_flags(flags)
.with_init(|c| c.execute_batch(STARTUP_SQL));
let pool: SqlitePool = r2d2::Pool::builder()
.test_on_check_out(true) // no noticeable performance hit
.min_idle(Some(min_size))
.max_size(max_size)
.build(manager)
.unwrap();
info!(
"Built a connection pool {:?} (min={}, max={})",
name, min_size, max_size
);
pool
}
/// Build a single database connection, with provided flags
pub fn build_conn(flags: OpenFlags) -> Result<Connection> {
let settings = SETTINGS.read().unwrap();
let db_dir = &settings.database.data_directory;
let full_path = Path::new(db_dir).join(DB_FILE);
// create a connection
Ok(Connection::open_with_flags(&full_path, flags)?)
}
/// Spawn a database writer that persists events to the SQLite store.
pub async fn db_writer(
mut event_rx: tokio::sync::mpsc::Receiver<Event>,
bcast_tx: tokio::sync::broadcast::Sender<Event>,
metadata_tx: tokio::sync::broadcast::Sender<Event>,
mut shutdown: tokio::sync::broadcast::Receiver<()>,
) -> tokio::task::JoinHandle<Result<()>> {
let settings = SETTINGS.read().unwrap();
// are we performing NIP-05 checking?
let nip05_active = settings.verified_users.is_active();
// are we requriing NIP-05 user verification?
let nip05_enabled = settings.verified_users.is_enabled();
task::spawn_blocking(move || {
// get database configuration settings
let settings = SETTINGS.read().unwrap();
let db_dir = &settings.database.data_directory;
let full_path = Path::new(db_dir).join(DB_FILE);
// create a connection pool
let pool = build_pool(
"event writer",
OpenFlags::SQLITE_OPEN_READ_WRITE | OpenFlags::SQLITE_OPEN_CREATE,
1,
4,
false,
);
info!("opened database {:?} for writing", full_path);
upgrade_db(&mut pool.get()?)?;
// Make a copy of the whitelist
let whitelist = &settings.authorization.pubkey_whitelist.clone();
// get rate limit settings
let rps_setting = settings.limits.messages_per_sec;
let mut most_recent_rate_limit = Instant::now();
let mut lim_opt = None;
let clock = governor::clock::QuantaClock::default();
if let Some(rps) = rps_setting {
if rps > 0 {
info!("Enabling rate limits for event creation ({}/sec)", rps);
let quota = core::num::NonZeroU32::new(rps * 60).unwrap();
lim_opt = Some(RateLimiter::direct(Quota::per_minute(quota)));
}
}
loop {
if shutdown.try_recv().is_ok() {
info!("shutting down database writer");
break;
}
// call blocking read on channel
let next_event = event_rx.blocking_recv();
// if the channel has closed, we will never get work
if next_event.is_none() {
break;
}
let mut event_write = false;
let event = next_event.unwrap();
// check if this event is authorized.
if let Some(allowed_addrs) = whitelist {
debug!("Checking against pubkey whitelist");
// if the event address is not in allowed_addrs.
if !allowed_addrs.contains(&event.pubkey) {
info!(
"Rejecting event {}, unauthorized author",
event.get_event_id_prefix()
);
// TODO: define a channel that can send NOTICEs back to the client.
continue;
}
}
// send any metadata events to the NIP-05 verifier
if nip05_active && event.is_kind_metadata() {
// we are sending this prior to even deciding if we
// persist it. this allows the nip05 module to
// inspect it, update if necessary, or persist a new
// event and broadcast it itself.
metadata_tx.send(event.clone()).ok();
}
// check for NIP-05 verification
if nip05_enabled {
match nip05::query_latest_user_verification(pool.get()?, event.pubkey.to_owned()) {
Ok(uv) => {
if uv.is_valid() {
info!(
"new event from verified author ({:?},{:?})",
uv.name.to_string(),
event.get_author_prefix()
);
} else {
info!("rejecting event, author ({:?} / {:?}) verification invalid (expired/wrong domain)",
uv.name.to_string(),
event.get_author_prefix()
);
continue;
}
}
Err(Error::SqlError(rusqlite::Error::QueryReturnedNoRows)) => {
debug!(
"no verification records found for pubkey: {:?}",
event.get_author_prefix()
);
continue;
}
Err(e) => {
warn!("checking nip05 verification status failed: {:?}", e);
continue;
}
}
}
// TODO: cache recent list of authors to remove a DB call.
let start = Instant::now();
match write_event(&mut pool.get()?, &event) {
Ok(updated) => {
if updated == 0 {
trace!("ignoring duplicate event");
} else {
info!(
"persisted event {:?} from {:?} in {:?}",
event.get_event_id_prefix(),
event.get_author_prefix(),
start.elapsed()
);
event_write = true;
// send this out to all clients
bcast_tx.send(event.clone()).ok();
}
}
Err(err) => {
warn!("event insert failed: {:?}", err);
}
}
// use rate limit, if defined, and if an event was actually written.
if event_write {
if let Some(ref lim) = lim_opt {
if let Err(n) = lim.check() {
let wait_for = n.wait_time_from(clock.now());
// check if we have recently logged rate
// limits, but print out a message only once
// per second.
if most_recent_rate_limit.elapsed().as_secs() > 10 {
warn!(
"rate limit reached for event creation (sleep for {:?}) (suppressing future messages for 10 seconds)",
wait_for
);
// reset last rate limit message
most_recent_rate_limit = Instant::now();
}
// block event writes, allowing them to queue up
thread::sleep(wait_for);
continue;
}
}
}
}
info!("database connection closed");
Ok(())
})
}
/// Persist an event to the database, returning rows added.
pub fn write_event(conn: &mut PooledConnection, e: &Event) -> Result<usize> {
// start transaction
let tx = conn.transaction()?;
// get relevant fields from event and convert to blobs.
let id_blob = hex::decode(&e.id).ok();
let pubkey_blob = hex::decode(&e.pubkey).ok();
let event_str = serde_json::to_string(&e).ok();
// ignore if the event hash is a duplicate.
let ins_count = tx.execute(
"INSERT OR IGNORE INTO event (event_hash, created_at, kind, author, content, first_seen, hidden) VALUES (?1, ?2, ?3, ?4, ?5, strftime('%s','now'), FALSE);",
params![id_blob, e.created_at, e.kind, pubkey_blob, event_str]
)?;
if ins_count == 0 {
// if the event was a duplicate, no need to insert event or
// pubkey references.
return Ok(ins_count);
}
// remember primary key of the event most recently inserted.
let ev_id = tx.last_insert_rowid();
// add all tags to the tag table
for tag in e.tags.iter() {
// ensure we have 2 values.
if tag.len() >= 2 {
let tagname = &tag[0];
let tagval = &tag[1];
// if tagvalue is hex;
if is_hex(tagval) {
tx.execute(
"INSERT OR IGNORE INTO tag (event_id, name, value_hex) VALUES (?1, ?2, ?3)",
params![ev_id, &tagname, hex::decode(&tagval).ok()],
)?;
} else {
tx.execute(
"INSERT OR IGNORE INTO tag (event_id, name, value) VALUES (?1, ?2, ?3)",
params![ev_id, &tagname, &tagval],
)?;
}
}
}
// if this event is for a metadata update, hide every other kind=0
// event from the same author that was issued earlier than this.
if e.kind == 0 {
let update_count = tx.execute(
"UPDATE event SET hidden=TRUE WHERE id!=? AND kind=0 AND author=? AND created_at <= ? and hidden!=TRUE",
params![ev_id, hex::decode(&e.pubkey).ok(), e.created_at],
)?;
if update_count > 0 {
info!(
"hid {} older metadata events for author {:?}",
update_count,
e.get_author_prefix()
);
}
}
// if this event is for a contact update, hide every other kind=3
// event from the same author that was issued earlier than this.
if e.kind == 3 {
let update_count = tx.execute(
"UPDATE event SET hidden=TRUE WHERE id!=? AND kind=3 AND author=? AND created_at <= ? and hidden!=TRUE",
params![ev_id, hex::decode(&e.pubkey).ok(), e.created_at],
)?;
if update_count > 0 {
info!(
"hid {} older contact events for author {:?}",
update_count,
e.get_author_prefix()
);
}
}
tx.commit()?;
Ok(ins_count)
}
/// Serialized event associated with a specific subscription request.
#[derive(PartialEq, Debug, Clone)]
pub struct QueryResult {
/// Subscription identifier
pub sub_id: String,
/// Serialized event
pub event: String,
}
/// Produce a arbitrary list of '?' parameters.
fn repeat_vars(count: usize) -> String {
if count == 0 {
return "".to_owned();
}
let mut s = "?,".repeat(count);
// Remove trailing comma
s.pop();
s
}
/// Create a dynamic SQL query string and params from a subscription.
fn query_from_sub(sub: &Subscription) -> (String, Vec<Box<dyn ToSql>>) {
// build a dynamic SQL query. all user-input is either an integer
// (sqli-safe), or a string that is filtered to only contain
// hexadecimal characters. Strings that require escaping (tag
// names/values) use parameters.
let mut query =
"SELECT DISTINCT(e.content) FROM event e LEFT JOIN tag t ON e.id=t.event_id ".to_owned();
// parameters
let mut params: Vec<Box<dyn ToSql>> = vec![];
// for every filter in the subscription, generate a where clause
let mut filter_clauses: Vec<String> = Vec::new();
for f in sub.filters.iter() {
// individual filter components
let mut filter_components: Vec<String> = Vec::new();
// Query for "authors", allowing prefix matches
if let Some(authvec) = &f.authors {
// take each author and convert to a hexsearch
let mut auth_searches: Vec<String> = vec![];
for auth in authvec {
match hex_range(auth) {
Some(HexSearch::Exact(ex)) => {
auth_searches.push("author=?".to_owned());
params.push(Box::new(ex));
}
Some(HexSearch::Range(lower, upper)) => {
auth_searches.push("(author>? AND author<?)".to_owned());
params.push(Box::new(lower));
params.push(Box::new(upper));
}
Some(HexSearch::LowerOnly(lower)) => {
auth_searches.push("author>?".to_owned());
params.push(Box::new(lower));
}
None => {
info!("Could not parse hex range from author {:?}", auth);
}
}
}
let authors_clause = format!("({})", auth_searches.join(" OR "));
filter_components.push(authors_clause);
}
// Query for Kind
if let Some(ks) = &f.kinds {
// kind is number, no escaping needed
let str_kinds: Vec<String> = ks.iter().map(|x| x.to_string()).collect();
let kind_clause = format!("kind IN ({})", str_kinds.join(", "));
filter_components.push(kind_clause);
}
// Query for event, allowing prefix matches
if let Some(idvec) = &f.ids {
// take each author and convert to a hexsearch
let mut id_searches: Vec<String> = vec![];
for id in idvec {
match hex_range(id) {
Some(HexSearch::Exact(ex)) => {
id_searches.push("event_hash=?".to_owned());
params.push(Box::new(ex));
}
Some(HexSearch::Range(lower, upper)) => {
id_searches.push("(event_hash>? AND event_hash<?)".to_owned());
params.push(Box::new(lower));
params.push(Box::new(upper));
}
Some(HexSearch::LowerOnly(lower)) => {
id_searches.push("event_hash>?".to_owned());
params.push(Box::new(lower));
}
None => {
info!("Could not parse hex range from id {:?}", id);
}
}
}
let id_clause = format!("({})", id_searches.join(" OR "));
filter_components.push(id_clause);
}
// Query for tags
if let Some(map) = &f.tags {
for (key, val) in map.iter() {
let mut str_vals: Vec<Box<dyn ToSql>> = vec![];
let mut blob_vals: Vec<Box<dyn ToSql>> = vec![];
for v in val {
if is_hex(v) {
if let Ok(h) = hex::decode(&v) {
blob_vals.push(Box::new(h));
}
} else {
str_vals.push(Box::new(v.to_owned()));
}
}
// create clauses with "?" params for each tag value being searched
let str_clause = format!("value IN ({})", repeat_vars(str_vals.len()));
let blob_clause = format!("value_hex IN ({})", repeat_vars(blob_vals.len()));
let tag_clause = format!("(name=? AND ({} OR {}))", str_clause, blob_clause);
// add the tag name as the first parameter
params.push(Box::new(key.to_owned()));
// add all tag values that are plain strings as params
params.append(&mut str_vals);
// add all tag values that are blobs as params
params.append(&mut blob_vals);
filter_components.push(tag_clause);
}
}
// Query for timestamp
if f.since.is_some() {
let created_clause = format!("created_at > {}", f.since.unwrap());
filter_components.push(created_clause);
}
// Query for timestamp
if f.until.is_some() {
let until_clause = format!("created_at < {}", f.until.unwrap());
filter_components.push(until_clause);
}
// combine all clauses, and add to filter_clauses
if !filter_components.is_empty() {
let mut fc = "( ".to_owned();
fc.push_str(&filter_components.join(" AND "));
fc.push_str(" )");
filter_clauses.push(fc);
}
}
// never display hidden events
query.push_str(" WHERE hidden!=TRUE ");
// combine all filters with OR clauses, if any exist
if !filter_clauses.is_empty() {
query.push_str(" AND (");
query.push_str(&filter_clauses.join(" OR "));
query.push_str(") ");
}
// add order clause
query.push_str(" ORDER BY created_at ASC");
debug!("query string: {}", query);
(query, params)
}
/// Perform a database query using a subscription.
///
/// The [`Subscription`] is converted into a SQL query. Each result
/// is published on the `query_tx` channel as it is returned. If a
/// message becomes available on the `abandon_query_rx` channel, the
/// query is immediately aborted.
pub async fn db_query(
sub: Subscription,
conn: PooledConnection,
query_tx: tokio::sync::mpsc::Sender<QueryResult>,
mut abandon_query_rx: tokio::sync::oneshot::Receiver<()>,
) {
task::spawn_blocking(move || {
debug!("going to query for: {:?}", sub);
let mut row_count: usize = 0;
let start = Instant::now();
// generate SQL query
let (q, p) = query_from_sub(&sub);
// execute the query. Don't cache, since queries vary so much.
let mut stmt = conn.prepare(&q)?;
let mut event_rows = stmt.query(rusqlite::params_from_iter(p))?;
while let Some(row) = event_rows.next()? {
// check if this is still active (we could do this every N rows)
if abandon_query_rx.try_recv().is_ok() {
debug!("query aborted");
return Ok(());
}
row_count += 1;
let event_json = row.get(0)?;
query_tx
.blocking_send(QueryResult {
sub_id: sub.get_id(),
event: event_json,
})
.ok();
}
debug!(
"query completed ({} rows) in {:?}",
row_count,
start.elapsed()
);
let ok: Result<()> = Ok(());
ok
});
}