feat(blog) pagination

backend/src/api/get/get_page_count.rs

@@ -0,0 +1,25 @@
+use crate::constants::PAGE_SIZE;
+use axum::extract::State;
+use axum::Json;
+use serde_json::{json, Value};
+use sqlx::{query, PgPool, Row};
+use tracing::error;
+
+pub async fn get_page_count(
+    State(db_connection): State<PgPool>,
+) -> Result<Json<Value>, Json<Value>> {
+    match query("select cast(ceil(count(*) / $1) as integer) as res from post")
+        .bind(PAGE_SIZE as f32)
+        .fetch_one(&db_connection)
+        .await
+    {
+        Ok(res) => {
+            let res: i32 = res.get("res");
+            Ok(Json::from(json!({"res": res})))
+        }
+        Err(e) => {
+            error!("Failed to get blog page count: {}", e.to_string());
+            Err(Json::from(json!({"error": e.to_string()})))
+        }
+    }
+}