feat: store accounts and per-device sessions for members

db/migrations/00003_member_accounts.sql

@@ -0,0 +1,25 @@
+-- +goose Up
+-- 一个会话对应一个成员 token，同一个成员可以在多台设备上各有一个会话。
+CREATE TABLE member_sessions (
+    token_hash bytea PRIMARY KEY,
+    member_id uuid NOT NULL REFERENCES members ON DELETE CASCADE,
+    created_at timestamptz NOT NULL DEFAULT now()
+);
+
+CREATE INDEX ON member_sessions (member_id);
+
+-- bot 成员只通过 API Key 使用 HTTP 接口，不需要会话。
+INSERT INTO member_sessions (token_hash, member_id, created_at)
+SELECT m.token_hash, m.id, m.created_at FROM members m
+WHERE NOT EXISTS (SELECT FROM rooms r WHERE r.bot_member_id = m.id);
+
+ALTER TABLE members DROP COLUMN token_hash;
+
+-- 设置了用户名的成员是已注册的账号，否则是游客。用户名只能由小写字母、数字、下划线和连字符组成，所以按原文唯一即可。
+-- 邮箱属于账号，在所有设备上一致；游客没有账号，不替匿名身份保存个人信息，邮箱只存在游客自己的浏览器里。
+ALTER TABLE members
+    ADD COLUMN username text UNIQUE,
+    ADD COLUMN password_hash text,
+    ADD CHECK (password_hash IS NULL OR username IS NOT NULL),
+    ADD COLUMN email text,
+    ADD CHECK (email IS NULL OR username IS NOT NULL);

db/queries/members.sql

@@ -1,14 +1,50 @@
 -- name: CreateMember :one
-INSERT INTO members (token_hash, name) VALUES (@token_hash, @name)
+INSERT INTO members (name) VALUES (@name)
 RETURNING *;
 
+-- name: CreateSession :exec
+INSERT INTO member_sessions (token_hash, member_id) VALUES (@token_hash, @member_id);
+
 -- name: MemberByToken :one
-SELECT * FROM members WHERE token_hash = @token_hash;
+SELECT * FROM members WHERE id = (SELECT member_id FROM member_sessions WHERE token_hash = @token_hash);
 
 -- name: UpdateMember :one
--- 只覆盖传入的列，分别修改昵称和头像的两个并发请求因此不会互相还原；头像哈希传入空串表示清除。
+-- 只覆盖传入的列，分别修改昵称和头像的两个并发请求因此不会互相还原；头像哈希和邮箱传入空串表示清除。游客的邮箱总是 NULL。
 UPDATE members
 SET name = coalesce(sqlc.narg(name), name),
-    avatar_hash = CASE WHEN sqlc.narg(avatar_hash)::text IS NULL THEN avatar_hash ELSE NULLIF(sqlc.narg(avatar_hash)::text, '') END
+    avatar_hash = CASE WHEN sqlc.narg(avatar_hash)::text IS NULL THEN avatar_hash ELSE NULLIF(sqlc.narg(avatar_hash)::text, '') END,
+    email = CASE WHEN username IS NULL THEN NULL WHEN sqlc.narg(email)::text IS NULL THEN email ELSE NULLIF(sqlc.narg(email)::text, '') END
 WHERE id = @id
 RETURNING *;
+
+-- name: MemberAccountProfile :one
+SELECT username, email FROM members WHERE id = @id;
+
+-- name: RegisterMember :execrows
+-- 只给游客设置：已经注册过的成员不受影响，影响的行数为 0。
+UPDATE members SET username = @username, password_hash = @password_hash
+WHERE id = @id AND username IS NULL;
+
+-- name: AccountByUsername :one
+SELECT * FROM members WHERE username = @username;
+
+-- name: SetMemberPassword :execrows
+UPDATE members SET password_hash = @password_hash WHERE id = @id AND username IS NOT NULL;
+
+-- name: LockAccountPassword :one
+-- 用互斥的 FOR NO KEY UPDATE，不用 FOR SHARE：同一个账号的修改和重置依次进行，后一个读到的是前一个写入的密码哈希。
+SELECT coalesce(password_hash, '')::text AS password_hash FROM members WHERE id = @id AND username IS NOT NULL FOR NO KEY UPDATE;
+
+-- name: MemberHasSession :one
+SELECT EXISTS (SELECT FROM member_sessions WHERE token_hash = @token_hash AND member_id = @member_id);
+
+-- name: LockMemberPassword :one
+-- FOR SHARE 让修改密码等到这次登录提交之后，它随后删除会话时会删掉这次登录签发的会话。
+SELECT coalesce(password_hash, '')::text AS password_hash FROM members WHERE id = @id FOR SHARE;
+
+-- name: DeleteSession :execrows
+DELETE FROM member_sessions WHERE token_hash = @token_hash;
+
+-- name: DeleteMemberSessions :exec
+-- keep 为 NULL 时删除这个成员的全部会话。
+DELETE FROM member_sessions WHERE member_id = @member_id AND token_hash IS DISTINCT FROM sqlc.narg(keep)::bytea;