Move bot configuration to SQL land

1 files changed, 100 insertions, 0 deletions

diff --git a/src/DB.zig b/src/DB.zig
new file mode 100644
index 0000000..6510e7c
--- /dev/null
+++ b/src/DB.zig
@@ -0,0 +1,100 @@
+const sqlite = @import("sqlite");
+const std = @import("std");
+
+const DB = @This();
+
+const target_version = 1;
+
+sql: sqlite.Db,
+
+pub const InlineBotType = enum(u32) {
+    blacklisted = 0,
+    whitelisted = 1,
+};
+
+pub fn init(db_path: [:0]const u8) !DB {
+    const sql = try sqlite.Db.init(.{
+        .mode = .{ .File = db_path },
+        .open_flags = .{
+            .write = true,
+            .create = true,
+        },
+        .threading_mode = .MultiThread,
+    });
+
+    return DB{
+        .sql = sql,
+    };
+}
+
+pub fn deinit(self: *DB) void {
+    self.sql.deinit();
+}
+
+pub fn getInlineBotType(self: *DB, id: i64) !?InlineBotType {
+    const row = try self.sql.one(u32, "SELECT type FROM inline_bots WHERE id = ?", .{}, .{ .id = id });
+    if (row) |r| {
+        return @enumFromInt(r);
+    }
+    return null;
+}
+
+pub fn setInlineBotType(self: *DB, id: i64, ty: InlineBotType) !void {
+    try self.sql.exec("INSERT OR REPLACE INTO inline_bots (id, type) VALUES (?, ?)", .{}, .{ id, @intFromEnum(ty) });
+}
+
+pub fn upgrade(self: *DB) !void {
+    try self.sql.exec("CREATE TABLE IF NOT EXISTS version(id INTEGER PRIMARY KEY, version INTEGER)", .{}, .{});
+    const row = try self.sql.one(struct { version: u32 }, "SELECT version FROM version WHERE id = 0", .{}, .{});
+    var current_ver: u32 = if (row) |r| r.version else 0;
+
+    if (current_ver == target_version) {
+        std.log.info("Database is up to date", .{});
+        return;
+    } else if (current_ver > target_version) {
+        std.log.err("Database has a higher version than supported?", .{});
+        return error.CorruptedDatabase;
+    }
+
+    std.log.info("Updating database from version {} to {}", .{ current_ver, target_version });
+
+    var setVerStmt = try self.sql.prepare("INSERT OR REPLACE INTO version(id, version) VALUES (0, ?)");
+    defer setVerStmt.deinit();
+
+    while (current_ver < target_version) : (current_ver += 1) {
+        std.log.info("Updating database step from {}", .{current_ver});
+        try self.upgradeStep(current_ver + 1);
+        setVerStmt.reset();
+        try setVerStmt.exec(.{}, .{ current_ver + 1 });
+    }
+}
+
+fn upgradeStep(self: *DB, new_version: u32) !void {
+    switch (new_version) {
+        1 => {
+            try self.sql.exec("DROP TABLE IF EXISTS inline_bots_enum", .{}, .{});
+            try self.sql.exec(
+                \\CREATE TABLE inline_bots_enum (
+                \\  id INTEGER PRIMARY KEY,
+                \\  value TEXT UNIQUE
+                \\)
+            , .{}, .{});
+            try self.sql.exec(
+                \\INSERT INTO inline_bots_enum(id, value)
+                \\VALUES (?, 'blacklisted'), (?, 'whitelisted')
+            , .{}, .{
+                .blacklisted = @intFromEnum(InlineBotType.blacklisted),
+                .whitelisted = @intFromEnum(InlineBotType.whitelisted),
+            });
+
+            try self.sql.exec("DROP TABLE IF EXISTS inline_bots", .{}, .{});
+            try self.sql.exec(
+                \\CREATE TABLE inline_bots (
+                \\  id INTEGER PRIMARY KEY,
+                \\  type INTEGER REFERENCES inline_bots_enum(id)
+                \\)
+            , .{}, .{});
+        },
+        else => unreachable,
+    }
+}