Added a query to give the aggregate of the attendence data

Author: tejasai2007

src/graphql/queries/member_queries.rs

@@ -1,4 +1,6 @@
-use crate::models::{attendance::AttendanceRecord, status_update::StatusUpdateRecord};
+use crate::models::{
+    attendance::Aggregate, attendance::AttendanceRecord, status_update::StatusUpdateRecord,
+};
 use async_graphql::{ComplexObject, Context, Object, Result};
 use chrono::NaiveDate;
 use sqlx::PgPool;
@@ -17,8 +19,13 @@ pub struct AttendanceInfo {
     member_id: i32,
 }
 
+pub struct Lab;
+
 #[Object]
 impl MemberQueries {
+    async fn lab(&self, _ctx: &Context<'_>) -> Lab {
+        Lab
+    }
     pub async fn all_members(
         &self,
         ctx: &Context<'_>,
@@ -336,3 +343,62 @@ impl Member {
         }
     }
 }
+
+#[Object]
+
+impl Lab {
+    pub async fn attendance(
+        &self,
+        ctx: &Context<'_>,
+        start_date: NaiveDate,
+        end_date: NaiveDate,
+    ) -> Result<Vec<Aggregate>> {
+        let pool = ctx.data::<Arc<PgPool>>().expect("Pool must be in context.");
+
+        // will give the total count
+        let mut query = sqlx::QueryBuilder::new(
+            r#"
+        SELECT 
+            all_dates.date,  
+            p.present_count
+        FROM (
+            SELECT 
+                date, 
+                COUNT(*) AS total_count
+            FROM attendance
+            WHERE date BETWEEN "#,
+        );
+
+        query.push_bind(start_date);
+        query.push(" AND ");
+        query.push_bind(end_date);
+        query.push(" GROUP BY date ) AS all_dates ");
+
+        // sub query of present members joined with the above total countS
+        query.push(
+            "LEFT JOIN (
+                SELECT 
+                    date, 
+                    COUNT(*) AS present_count
+                FROM attendance
+                WHERE is_present = 't'
+                AND date BETWEEN ",
+        );
+        query.push_bind(start_date);
+        query.push(" AND ");
+        query.push_bind(end_date);
+        query.push(
+            " GROUP BY date
+            ) AS p
+            ON all_dates.date = p.date
+            ORDER BY all_dates.date;",
+        );
+
+        let results: Vec<Aggregate> = query
+            .build_query_as::<Aggregate>()
+            .fetch_all(pool.as_ref())
+            .await?;
+
+        Ok(results)
+    }
+}

src/models/attendance.rs

@@ -21,3 +21,9 @@ pub struct MarkAttendanceInput {
     pub date: NaiveDate,
     pub hmac_signature: String,
 }
+
+#[derive(FromRow, SimpleObject)]
+pub struct Aggregate {
+    pub date: NaiveDate,
+    pub present_count: Option<i64>,
+}