backend/internal/api/auth.go

@@ -208,8 +208,8 @@ func (h *AuthHandler) Logout(c *gin.Context) {
 // validateCredentials 校验用户名和密码格式。
 // 返回空字符串表示校验通过，否则返回错误描述。
 func validateCredentials(username, password string) string {
-	if len(username) < 3 || len(username) > 64 {
+	if len(username) > 64 {
-		return "username must be 3-64 characters"
+		return "username must not exceed 64 characters"
 	}
 	if len(password) < 8 || len(password) > 72 {
 		return "password must be 8-72 characters"

backend/migrations/001_users.up.sql

@@ -10,6 +10,14 @@ CREATE TABLE IF NOT EXISTS users (
 -- 用户名索引（用于登录查询）
 CREATE INDEX IF NOT EXISTS idx_users_username ON users(username);
 
+-- 表和列注释
+COMMENT ON TABLE users IS '用户表，存储系统所有注册用户的基本信息';
+COMMENT ON COLUMN users.id IS '用户唯一标识符 (UUID)';
+COMMENT ON COLUMN users.username IS '用户名，最大 64 字符，全局唯一';
+COMMENT ON COLUMN users.password_hash IS '密码哈希值，使用 bcrypt 算法（cost=10）';
+COMMENT ON COLUMN users.created_at IS '用户注册时间';
+COMMENT ON COLUMN users.updated_at IS '用户信息最后更新时间';
+
 -- Refresh Token 表
 CREATE TABLE IF NOT EXISTS refresh_tokens (
     id         UUID PRIMARY KEY DEFAULT gen_random_uuid(),
@@ -24,3 +32,11 @@ CREATE INDEX IF NOT EXISTS idx_refresh_tokens_token_hash ON refresh_tokens(token
 
 -- 用户 ID 索引（用于登出所有设备）
 CREATE INDEX IF NOT EXISTS idx_refresh_tokens_user_id ON refresh_tokens(user_id);
+
+-- 表和列注释
+COMMENT ON TABLE refresh_tokens IS 'Refresh Token 表，用于 JWT 双 token 机制的长期身份验证';
+COMMENT ON COLUMN refresh_tokens.id IS 'Token 唯一标识符 (UUID)';
+COMMENT ON COLUMN refresh_tokens.user_id IS '所属用户 ID，外键关联 users 表，用户删除时级联删除';
+COMMENT ON COLUMN refresh_tokens.token_hash IS 'Token 哈希值，使用 SHA-256 算法，十六进制编码 (64 字符)';
+COMMENT ON COLUMN refresh_tokens.expires_at IS 'Token 过期时间，默认有效期 7 天';
+COMMENT ON COLUMN refresh_tokens.created_at IS 'Token 创建时间';

backend/migrations/002_messages.up.sql

@@ -2,10 +2,12 @@
 CREATE TABLE IF NOT EXISTS messages (
     id          BIGSERIAL PRIMARY KEY,
     session_id  UUID NOT NULL,
-    role        VARCHAR(16) NOT NULL,  -- "user" | "assistant" | "system"
+    role        VARCHAR(10) NOT NULL,
     content     TEXT NOT NULL,
     tokens_used INTEGER NOT NULL DEFAULT 0,
-    created_at  TIMESTAMPTZ NOT NULL DEFAULT NOW()
+    created_at  TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+
+    CONSTRAINT check_tokens_non_negative CHECK (tokens_used >= 0)
 );
 
 -- 按会话查询消息（分页核心索引）
@@ -15,3 +17,12 @@ CREATE INDEX IF NOT EXISTS idx_messages_session_id_created_at
 -- 按会话查询最后一条消息
 CREATE INDEX IF NOT EXISTS idx_messages_session_id_id_desc
     ON messages(session_id, id DESC);
+
+-- 表和列注释
+COMMENT ON TABLE messages IS '消息表，存储所有会话的消息记录';
+COMMENT ON COLUMN messages.id IS '消息唯一标识符，自增序列';
+COMMENT ON COLUMN messages.session_id IS '所属会话 ID，关联 sessions 表';
+COMMENT ON COLUMN messages.role IS '消息角色，可选值: ''user'' (用户), ''assistant'' (AI 助手), ''system'' (系统)';
+COMMENT ON COLUMN messages.content IS '消息内容，无长度限制';
+COMMENT ON COLUMN messages.tokens_used IS '消息消耗的 token 数量，用于计费统计';
+COMMENT ON COLUMN messages.created_at IS '消息创建时间';

backend/migrations/003_sessions.up.sql

@@ -1,11 +1,22 @@
 CREATE TABLE IF NOT EXISTS sessions (
     id           UUID PRIMARY KEY,
     user_id      UUID NOT NULL,
-    title        VARCHAR(256) NOT NULL DEFAULT '新对话',
+    title        VARCHAR(100) NOT NULL DEFAULT '新对话',
     config       JSONB NOT NULL DEFAULT '{}',
     created_at   TIMESTAMPTZ NOT NULL DEFAULT NOW(),
-    updated_at   TIMESTAMPTZ NOT NULL DEFAULT NOW()
+    updated_at   TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+
+    CONSTRAINT check_title_length CHECK (char_length(title) >= 1 AND char_length(title) <= 100)
 );
 
 CREATE INDEX IF NOT EXISTS idx_sessions_user_id ON sessions (user_id);
 CREATE INDEX IF NOT EXISTS idx_sessions_user_updated ON sessions (user_id, updated_at DESC);
+
+-- 表和列注释
+COMMENT ON TABLE sessions IS '会话表，存储用户的对话会话信息';
+COMMENT ON COLUMN sessions.id IS '会话唯一标识符 (UUID)';
+COMMENT ON COLUMN sessions.user_id IS '所属用户 ID，关联 users 表';
+COMMENT ON COLUMN sessions.title IS '会话标题，默认为"新对话"，长度 1-100 字符';
+COMMENT ON COLUMN sessions.config IS '会话配置 (JSONB)，包含: tts_enabled (布尔), detail_level (''low''/''high''), language (语言代码), scenario (情景 ID)';
+COMMENT ON COLUMN sessions.created_at IS '会话创建时间';
+COMMENT ON COLUMN sessions.updated_at IS '会话最后更新时间';

backend/migrations/004_user_scenarios.up.sql

@@ -5,18 +5,19 @@ CREATE TABLE user_scenarios (
     id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
     user_id UUID NOT NULL REFERENCES users(id) ON DELETE CASCADE,
     name VARCHAR(50) NOT NULL,
-    icon VARCHAR(10) DEFAULT '✨',
+    icon VARCHAR(20) DEFAULT '✨',
     description VARCHAR(100),
     prompt TEXT NOT NULL,
-    greeting VARCHAR(200),
+    greeting VARCHAR(500),
     language VARCHAR(10) DEFAULT 'zh-CN',
     created_at TIMESTAMP NOT NULL DEFAULT NOW(),
     updated_at TIMESTAMP NOT NULL DEFAULT NOW(),
 
     CONSTRAINT unique_user_scenario UNIQUE(user_id, name),
     CONSTRAINT check_name_length CHECK (char_length(name) >= 2 AND char_length(name) <= 50),
-    CONSTRAINT check_description_length CHECK (description IS NULL OR (char_length(description) >= 1 AND char_length(description) <= 100)),
+    CONSTRAINT check_description_length CHECK (description IS NULL OR char_length(description) <= 100),
-    CONSTRAINT check_prompt_length CHECK (char_length(prompt) >= 10 AND char_length(prompt) <= 2000)
+    CONSTRAINT check_prompt_length CHECK (char_length(prompt) >= 10),
+    CONSTRAINT check_greeting_length CHECK (greeting IS NULL OR char_length(greeting) <= 500)
 );
 
 -- 为用户 ID 创建索引，加速查询
@@ -25,12 +26,15 @@ CREATE INDEX idx_user_scenarios_user_id ON user_scenarios(user_id);
 -- 为创建时间创建索引，用于排序
 CREATE INDEX idx_user_scenarios_created_at ON user_scenarios(created_at DESC);
 
-COMMENT ON TABLE user_scenarios IS '用户自建情景表';
+-- 表和列注释
-COMMENT ON COLUMN user_scenarios.id IS '情景唯一标识';
+COMMENT ON TABLE user_scenarios IS '用户自建情景表，存储用户创建的 AI 对话情景配置';
-COMMENT ON COLUMN user_scenarios.user_id IS '所属用户 ID，外键关联 users 表';
+COMMENT ON COLUMN user_scenarios.id IS '情景唯一标识符 (UUID)';
-COMMENT ON COLUMN user_scenarios.name IS '情景名称，如"创意写作导师"';
+COMMENT ON COLUMN user_scenarios.user_id IS '所属用户 ID，外键关联 users 表，用户删除时级联删除';
-COMMENT ON COLUMN user_scenarios.icon IS 'Emoji 图标，如"🎨"';
+COMMENT ON COLUMN user_scenarios.name IS '情景名称 (2-50 字符)，如"创意写作导师"';
-COMMENT ON COLUMN user_scenarios.description IS '简短描述，可选，显示在情景卡片上';
+COMMENT ON COLUMN user_scenarios.icon IS 'Emoji 图标 (最多 20 字符)，支持复合 Emoji，如"🎨"';
-COMMENT ON COLUMN user_scenarios.prompt IS '角色 System Prompt，定义 AI 行为';
+COMMENT ON COLUMN user_scenarios.description IS '简短描述 (最多 100 字符)，可选，显示在情景卡片上';
-COMMENT ON COLUMN user_scenarios.greeting IS '首句引导，可选';
+COMMENT ON COLUMN user_scenarios.prompt IS '角色 System Prompt (最少 10 字符，无上限)，定义 AI 行为和对话风格';
-COMMENT ON COLUMN user_scenarios.language IS '默认语言，如 zh-CN、en-US';
+COMMENT ON COLUMN user_scenarios.greeting IS '首句引导 (最多 500 字符)，可选，AI 的开场白';
+COMMENT ON COLUMN user_scenarios.language IS '默认语言代码 (如 zh-CN、en-US、ja-JP)';
+COMMENT ON COLUMN user_scenarios.created_at IS '情景创建时间';
+COMMENT ON COLUMN user_scenarios.updated_at IS '情景最后更新时间';

backend/migrations/005_fix_user_scenarios_description.down.sql

@@ -1,15 +0,0 @@
--- 005_fix_user_scenarios_description.down.sql
--- 回滚：恢复原约束（description 必填，prompt 最小长度 50）
-
--- 注意：如果表中存在不符合原约束的数据，此回滚会失败
-
--- 1. 恢复 description 为必填
-ALTER TABLE user_scenarios
-    ALTER COLUMN description SET NOT NULL;
-
--- 2. 恢复 prompt 最小长度为 50
-ALTER TABLE user_scenarios
-    DROP CONSTRAINT IF EXISTS check_prompt_length;
-
-ALTER TABLE user_scenarios
-    ADD CONSTRAINT check_prompt_length CHECK (char_length(prompt) >= 50 AND char_length(prompt) <= 2000);

backend/migrations/005_fix_user_scenarios_description.up.sql

@@ -1,16 +0,0 @@
--- 005_fix_user_scenarios_description.up.sql
--- 修复 user_scenarios 表约束：description 允许为空，prompt 最小长度改为 10
-
--- 1. 允许 description 为空
-ALTER TABLE user_scenarios
-    ALTER COLUMN description DROP NOT NULL;
-
--- 2. 修复 prompt 长度约束（从 50 改为 10，与代码一致）
-ALTER TABLE user_scenarios
-    DROP CONSTRAINT IF EXISTS check_prompt_length;
-
-ALTER TABLE user_scenarios
-    ADD CONSTRAINT check_prompt_length CHECK (char_length(prompt) >= 10 AND char_length(prompt) <= 2000);
-
-COMMENT ON COLUMN user_scenarios.description IS '简短描述，可选，显示在情景卡片上（允许为空）';
-COMMENT ON COLUMN user_scenarios.prompt IS '角色 System Prompt，定义 AI 行为（10-2000 字符）';

check_constraints.sql

@@ -1,9 +0,0 @@
--- 检查 user_scenarios 表的所有约束
-SELECT
-    con.conname AS constraint_name,
-    con.contype AS constraint_type,
-    pg_get_constraintdef(con.oid) AS constraint_definition
-FROM pg_constraint con
-JOIN pg_class rel ON rel.oid = con.conrelid
-WHERE rel.relname = 'user_scenarios'
-ORDER BY con.conname;

fix_user_scenarios.sql

@@ -1,26 +0,0 @@
--- 快速修复脚本：修复 user_scenarios 表约束
--- 在生产 PostgreSQL 容器中执行此文件
-
--- 1. 允许 description 为空
-ALTER TABLE user_scenarios
-    ALTER COLUMN description DROP NOT NULL;
-
--- 2. 修复 prompt 长度约束（从 50 改为 10，与代码一致）
-ALTER TABLE user_scenarios
-    DROP CONSTRAINT IF EXISTS check_prompt_length;
-
-ALTER TABLE user_scenarios
-    ADD CONSTRAINT check_prompt_length CHECK (char_length(prompt) >= 10 AND char_length(prompt) <= 2000);
-
--- 更新注释
-COMMENT ON COLUMN user_scenarios.description IS '简短描述，可选，显示在情景卡片上（允许为空）';
-COMMENT ON COLUMN user_scenarios.prompt IS '角色 System Prompt，定义 AI 行为（10-2000 字符）';
-
--- 验证修改
-SELECT
-    con.conname AS constraint_name,
-    pg_get_constraintdef(con.oid) AS constraint_definition
-FROM pg_constraint con
-JOIN pg_class rel ON rel.oid = con.conrelid
-WHERE rel.relname = 'user_scenarios'
-    AND con.conname = 'check_prompt_length';

frontend/src/lib/i18n/en-US.ts

@@ -155,9 +155,9 @@ export const enUS: TranslationMap = {
   "auth.login": "Sign In",
   "auth.register": "Sign Up",
   "auth.username": "Username",
-  "auth.username.placeholder": "3-64 characters",
+  "auth.username.placeholder": "Enter username",
   "auth.password": "Password",
-  "auth.password.placeholder": "8-72 characters",
+  "auth.password.placeholder": "Enter password",
   "auth.submitting": "Please wait...",
   "auth.noAccount": "Don't have an account?",
   "auth.hasAccount": "Already have an account?",

frontend/src/lib/i18n/ja-JP.ts

@@ -155,9 +155,9 @@ export const jaJP: TranslationMap = {
   "auth.login": "ログイン",
   "auth.register": "新規登録",
   "auth.username": "ユーザー名",
-  "auth.username.placeholder": "3〜64文字",
+  "auth.username.placeholder": "ユーザー名を入力",
   "auth.password": "パスワード",
-  "auth.password.placeholder": "8〜72文字",
+  "auth.password.placeholder": "パスワードを入力",
   "auth.submitting": "お待ちください...",
   "auth.noAccount": "アカウントをお持ちでないですか？",
   "auth.hasAccount": "すでにアカウントをお持ちですか？",

frontend/src/lib/i18n/zh-CN.ts

@@ -155,9 +155,9 @@ export const zhCN: TranslationMap = {
   "auth.login": "登录",
   "auth.register": "注册",
   "auth.username": "用户名",
-  "auth.username.placeholder": "3-64 个字符",
+  "auth.username.placeholder": "请输入用户名",
   "auth.password": "密码",
-  "auth.password.placeholder": "8-72 个字符",
+  "auth.password.placeholder": "请输入密码",
   "auth.submitting": "请稍候...",
   "auth.noAccount": "还没有账号？",
   "auth.hasAccount": "已有账号？",