bsky feeds about music
music-atmosphere-feed.plyr.fm/
bsky
feed
zig
remove follows cache, fetch fresh each time
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
+2
-71
+2
-71
src/db.zig
+2
-71
src/db.zig
···
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// static buffer for db path (env vars return slices, zqlite needs sentinel)
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var db_path_buf: [256]u8 = undefined;
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// follows cache TTL: 5 minutes
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const FOLLOWS_CACHE_TTL_MS: i64 = 5 * 60 * 1000;
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pub fn init() !void {
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const db_path_env = posix.getenv("DATABASE_PATH") orelse "/data/feed.db";
···
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return rest[0..end];
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}
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-
/// get follows set for a DID, using cache if fresh
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+
/// get follows set for a DID
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fn getFollowsSet(alloc: std.mem.Allocator, requester_did: []const u8) !std.StringHashMap(void) {
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var set = std.StringHashMap(void).init(alloc);
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errdefer set.deinit();
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const now = std.time.milliTimestamp();
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// check cache freshness
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mutex.lock();
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const conn = db orelse {
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mutex.unlock();
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return error.NotInitialized;
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};
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var cache_fresh = false;
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var cache_rows = conn.rows(
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"SELECT cached_at FROM follows_cache WHERE requester_did = ? LIMIT 1",
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.{requester_did},
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) catch {
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mutex.unlock();
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return set;
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};
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-
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if (cache_rows.next()) |row| {
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const cached_at = row.int(0);
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if (now - cached_at < FOLLOWS_CACHE_TTL_MS) {
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cache_fresh = true;
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}
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}
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cache_rows.deinit();
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-
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if (cache_fresh) {
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// load from cache
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var follows_rows = conn.rows(
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"SELECT follows_did FROM follows_cache WHERE requester_did = ?",
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.{requester_did},
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) catch {
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mutex.unlock();
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return set;
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};
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-
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while (follows_rows.next()) |row| {
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const did = row.text(0);
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const owned = try alloc.dupe(u8, did);
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try set.put(owned, {});
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}
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follows_rows.deinit();
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mutex.unlock();
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std.debug.print("loaded {d} follows from cache for {s}\n", .{ set.count(), requester_did });
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return set;
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}
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mutex.unlock();
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// fetch fresh follows from API
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std.debug.print("fetching follows for {s}...\n", .{requester_did});
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const follows = atproto.getFollows(alloc, requester_did) catch |err| {
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std.debug.print("failed to fetch follows: {}\n", .{err});
···
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};
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defer alloc.free(follows);
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// parse follows and populate set
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var it = std.mem.splitScalar(u8, follows, '\n');
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while (it.next()) |did| {
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if (did.len == 0) continue;
···
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std.debug.print("fetched {d} follows for {s}\n", .{ set.count(), requester_did });
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// trigger lazy backfill for follows we haven't seen before
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// trigger backfill for follows we haven't seen before
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var dids_to_backfill: std.ArrayList([]const u8) = .empty;
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defer dids_to_backfill.deinit(alloc);
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var key_it = set.keyIterator();
···
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}
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if (dids_to_backfill.items.len > 0) {
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triggerBackfill(alloc, dids_to_backfill.items);
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}
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// update cache
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mutex.lock();
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defer mutex.unlock();
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// clear old cache for this user
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conn.exec("DELETE FROM follows_cache WHERE requester_did = ?", .{requester_did}) catch {};
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// insert new follows
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var set_it = set.keyIterator();
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while (set_it.next()) |key| {
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conn.exec(
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"INSERT INTO follows_cache (requester_did, follows_did, cached_at) VALUES (?, ?, ?)",
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.{ requester_did, key.*, now },
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) catch {};
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}
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return set;