feat: 为 get_tag_list 接口添加分页功能

src/handler/tag.rs

@@ -1,17 +1,38 @@
-use axum::{Json, extract::{Path, State}, http::StatusCode, response::IntoResponse};
+use axum::{Json, extract::{Path, Query, State}, http::StatusCode, response::IntoResponse};
 use serde::Deserialize;
 use uuid::Uuid;
 use validator::Validate;
 
-use crate::util::response::ApiErr;
+use crate::util::{response::ApiErr, pagination::{PaginatedResponse, PaginationParams}};
 use crate::{AppState};
 
 /// 获取所有标签
+#[derive(Deserialize, Validate)]
+pub struct GetTagListQuery {
+    #[serde(flatten)]
+    pub pagination: PaginationParams,
+}
+
 pub async fn get_tag_list(
     State(state): State<AppState>,
+    Query(query): Query<GetTagListQuery>,
 ) -> Result<impl IntoResponse, ApiErr> {
-    let tags = crate::service::get_all_tags(&state.pool).await?;
-    Ok(Json(tags))
+    query.validate()?;
+    let pool = &state.pool;
+
+    // 获取总数
+    let total = crate::service::get_tags_count(pool).await?;
+
+    // 获取分页数据
+    let tags = crate::service::get_tags_paginated(
+        pool,
+        query.pagination.page_size,
+        query.pagination.offset(),
+    ).await?;
+
+    let response = PaginatedResponse::new(tags, total, query.pagination.page, query.pagination.page_size);
+
+    Ok(Json(response))
 }
 
 /// 获取标签下的点位信息

src/service.rs

@@ -219,15 +219,44 @@ pub async fn get_points_paginated(
 
 // ==================== Tag 相关服务函数 ====================
 
-/// 获取所有标签
-pub async fn get_all_tags(
+/// 获取标签总数
+pub async fn get_tags_count(
     pool: &PgPool,
+) -> Result<i64, sqlx::Error> {
+    sqlx::query_scalar::<_, i64>(
+        r#"SELECT COUNT(*) FROM tag"#,
+    )
+    .fetch_one(pool)
+    .await
+}
+
+/// 获取分页标签列表
+pub async fn get_tags_paginated(
+    pool: &PgPool,
+    page_size: i32,
+    offset: u32,
 ) -> Result<Vec<crate::model::Tag>, sqlx::Error> {
-    query_as::<_, crate::model::Tag>(
-        r#"SELECT * FROM tag ORDER BY created_at"#
+    if page_size == 0 {
+        Ok(vec![])
+    } else if page_size == -1 {
+        sqlx::query_as::<_, crate::model::Tag>(
+            r#"SELECT * FROM tag ORDER BY created_at"#,
         )
         .fetch_all(pool)
         .await
+    } else {
+        sqlx::query_as::<_, crate::model::Tag>(
+            r#"
+            SELECT * FROM tag
+            ORDER BY created_at
+            LIMIT $1 OFFSET $2
+            "#,
+        )
+        .bind(page_size)
+        .bind(offset as i64)
+        .fetch_all(pool)
+        .await
+    }
 }
 
 /// 根据ID获取标签