Add page info field to connection object (#1177)

* Add page info field with dummy data to conneciton object

* query page info

* Enable metadata feature for torii

* Add page info field to connection object

* Fix page info query

* [WIP] Nullable page info

* Return page info even for limit/offset based pagination

crates/torii/graphql/src/constants.rs

@@ -21,6 +21,7 @@ pub const EVENT_TYPE_NAME: &str = "World__Event";
 pub const SOCIAL_TYPE_NAME: &str = "World__Social";
 pub const CONTENT_TYPE_NAME: &str = "World__Content";
 pub const METADATA_TYPE_NAME: &str = "World__Metadata";
+pub const PAGE_INFO_TYPE_NAME: &str = "World__PageInfo";
 pub const TRANSACTION_TYPE_NAME: &str = "World__Transaction";
 pub const QUERY_TYPE_NAME: &str = "World__Query";
 pub const SUBSCRIPTION_TYPE_NAME: &str = "World__Subscription";

crates/torii/graphql/src/object/connection/mod.rs

@@ -1,9 +1,13 @@
+use async_graphql::connection::PageInfo;
+use async_graphql::dynamic::indexmap::IndexMap;
 use async_graphql::dynamic::{Field, InputValue, ResolverContext, TypeRef};
 use async_graphql::{Error, Name, Value};
 use sqlx::sqlite::SqliteRow;
 use sqlx::Row;
 
+use self::page_info::PageInfoObject;
 use super::ObjectTrait;
+use crate::constants::PAGE_INFO_TYPE_NAME;
 use crate::query::order::Order;
 use crate::query::value_mapping_from_row;
 use crate::types::{GraphqlType, TypeData, TypeMapping, ValueMapping};
@@ -37,6 +41,10 @@ impl ConnectionObject {
                 TypeData::Simple(TypeRef::named_list(format!("{}Edge", type_name))),
             ),
             (Name::new("total_count"), TypeData::Simple(TypeRef::named_nn(TypeRef::INT))),
+            (
+                Name::new("page_info"),
+                TypeData::Nested((TypeRef::named_nn(PAGE_INFO_TYPE_NAME), IndexMap::new())),
+            ),
         ]);
 
         Self {
@@ -109,6 +117,7 @@ pub fn connection_output(
     id_column: &str,
     total_count: i64,
     is_external: bool,
+    page_info: PageInfo,
 ) -> sqlx::Result<ValueMapping> {
     let model_edges = data
         .iter()
@@ -134,5 +143,6 @@ pub fn connection_output(
     Ok(ValueMapping::from([
         (Name::new("total_count"), Value::from(total_count)),
         (Name::new("edges"), Value::List(model_edges?)),
+        (Name::new("page_info"), PageInfoObject::value(page_info)),
     ]))
 }

crates/torii/graphql/src/object/connection/page_info.rs

@@ -1,4 +1,7 @@
+use async_graphql::connection::PageInfo;
+use async_graphql::dynamic::indexmap::IndexMap;
 use async_graphql::dynamic::Field;
+use async_graphql::{Name, Value};
 
 use crate::mapping::PAGE_INFO_TYPE_MAPPING;
 use crate::object::{ObjectTrait, TypeMapping};
@@ -26,3 +29,26 @@ impl ObjectTrait for PageInfoObject {
         None
     }
 }
+
+impl PageInfoObject {
+    pub fn value(page_info: PageInfo) -> Value {
+        Value::Object(IndexMap::from([
+            (Name::new("has_previous_page"), Value::from(page_info.has_previous_page)),
+            (Name::new("has_next_page"), Value::from(page_info.has_next_page)),
+            (
+                Name::new("start_cursor"),
+                match page_info.start_cursor {
+                    Some(val) => Value::from(val),
+                    None => Value::Null,
+                },
+            ),
+            (
+                Name::new("end_cursor"),
+                match page_info.end_cursor {
+                    Some(val) => Value::from(val),
+                    None => Value::Null,
+                },
+            ),
+        ]))
+    }
+}

crates/torii/graphql/src/object/entity.rs

@@ -52,14 +52,15 @@ impl ObjectTrait for EntityObject {
                     let connection = parse_connection_arguments(&ctx)?;
                     let keys = parse_keys_argument(&ctx)?;
                     let total_count = count_rows(&mut conn, ENTITY_TABLE, &keys, &None).await?;
-                    let data = fetch_multiple_rows(
+                    let (data, page_info) = fetch_multiple_rows(
                         &mut conn,
                         ENTITY_TABLE,
                         EVENT_ID_COLUMN,
                         &keys,
                         &None,
                         &None,
                         &connection,
+                        total_count,
                     )
                     .await?;
                     let results = connection_output(
@@ -69,6 +70,7 @@ impl ObjectTrait for EntityObject {
                         EVENT_ID_COLUMN,
                         total_count,
                         false,
+                        page_info,
                     )?;
 
                     Ok(Some(Value::Object(results)))

crates/torii/graphql/src/object/event.rs

@@ -49,14 +49,15 @@ impl ObjectTrait for EventObject {
                     let connection = parse_connection_arguments(&ctx)?;
                     let keys = parse_keys_argument(&ctx)?;
                     let total_count = count_rows(&mut conn, EVENT_TABLE, &keys, &None).await?;
-                    let data = fetch_multiple_rows(
+                    let (data, page_info) = fetch_multiple_rows(
                         &mut conn,
                         EVENT_TABLE,
                         ID_COLUMN,
                         &keys,
                         &None,
                         &None,
                         &connection,
+                        total_count,
                     )
                     .await?;
                     let results = connection_output(
@@ -66,6 +67,7 @@ impl ObjectTrait for EventObject {
                         ID_COLUMN,
                         total_count,
                         false,
+                        page_info,
                     )?;
 
                     Ok(Some(Value::Object(results)))

crates/torii/graphql/src/object/metadata/mod.rs

@@ -1,8 +1,10 @@
+use async_graphql::connection::PageInfo;
 use async_graphql::dynamic::{Field, FieldFuture, TypeRef};
 use async_graphql::{Name, Value};
 use sqlx::sqlite::SqliteRow;
 use sqlx::{Pool, Row, Sqlite};
 
+use super::connection::page_info::PageInfoObject;
 use super::connection::{connection_arguments, cursor, parse_connection_arguments};
 use super::ObjectTrait;
 use crate::constants::{
@@ -54,19 +56,21 @@ impl ObjectTrait for MetadataObject {
                     let mut conn = ctx.data::<Pool<Sqlite>>()?.acquire().await?;
                     let connection = parse_connection_arguments(&ctx)?;
                     let total_count = count_rows(&mut conn, &table_name, &None, &None).await?;
-                    let data = fetch_multiple_rows(
+                    let (data, page_info) = fetch_multiple_rows(
                         &mut conn,
                         &table_name,
                         ID_COLUMN,
                         &None,
                         &None,
                         &None,
                         &connection,
+                        total_count,
                     )
                     .await?;
 
                     // convert json field to value_mapping expected by content object
-                    let results = metadata_connection_output(&data, &type_mapping, total_count)?;
+                    let results =
+                        metadata_connection_output(&data, &type_mapping, total_count, page_info)?;
 
                     Ok(Some(Value::Object(results)))
                 })
@@ -85,6 +89,7 @@ fn metadata_connection_output(
     data: &[SqliteRow],
     types: &TypeMapping,
     total_count: i64,
+    page_info: PageInfo,
 ) -> sqlx::Result<ValueMapping> {
     let edges = data
         .iter()
@@ -107,9 +112,10 @@ fn metadata_connection_output(
 
             value_mapping.insert(Name::new("content"), Value::Object(content));
 
-            let mut edge = ValueMapping::new();
-            edge.insert(Name::new("node"), Value::Object(value_mapping));
-            edge.insert(Name::new("cursor"), Value::String(cursor));
+            let edge = ValueMapping::from([
+                (Name::new("node"), Value::Object(value_mapping)),
+                (Name::new("cursor"), Value::String(cursor)),
+            ]);
 
             Ok(Value::Object(edge))
         })
@@ -118,6 +124,7 @@ fn metadata_connection_output(
     Ok(ValueMapping::from([
         (Name::new("total_count"), Value::from(total_count)),
         (Name::new("edges"), Value::List(edges?)),
+        (Name::new("page_info"), PageInfoObject::value(page_info)),
     ]))
 }
 

crates/torii/graphql/src/object/mod.rs

@@ -96,14 +96,15 @@ pub trait ObjectTrait: Send + Sync {
                     let mut conn = ctx.data::<Pool<Sqlite>>()?.acquire().await?;
                     let connection = parse_connection_arguments(&ctx)?;
                     let total_count = count_rows(&mut conn, &table_name, &None, &None).await?;
-                    let data = fetch_multiple_rows(
+                    let (data, page_info) = fetch_multiple_rows(
                         &mut conn,
                         &table_name,
                         ID_COLUMN,
                         &None,
                         &None,
                         &None,
                         &connection,
+                        total_count,
                     )
                     .await?;
                     let results = connection_output(
@@ -113,6 +114,7 @@ pub trait ObjectTrait: Send + Sync {
                         ID_COLUMN,
                         total_count,
                         false,
+                        page_info,
                     )?;
 
                     Ok(Some(Value::Object(results)))

crates/torii/graphql/src/object/model_data.rs

@@ -90,20 +90,27 @@ impl ObjectTrait for ModelDataObject {
                 let connection = parse_connection_arguments(&ctx)?;
                 let id_column = "event_id";
 
-                let data = fetch_multiple_rows(
+                let total_count = count_rows(&mut conn, &type_name, &None, &filters).await?;
+                let (data, page_info) = fetch_multiple_rows(
                     &mut conn,
                     &type_name,
                     id_column,
                     &None,
                     &order,
                     &filters,
                     &connection,
+                    total_count,
                 )
                 .await?;
-
-                let total_count = count_rows(&mut conn, &type_name, &None, &filters).await?;
-                let connection =
-                    connection_output(&data, &type_mapping, &order, id_column, total_count, true)?;
+                let connection = connection_output(
+                    &data,
+                    &type_mapping,
+                    &order,
+                    id_column,
+                    total_count,
+                    true,
+                    page_info,
+                )?;
 
                 Ok(Some(Value::Object(connection)))
             })

crates/torii/graphql/src/query/data.rs

@@ -1,6 +1,7 @@
+use async_graphql::connection::PageInfo;
 use sqlx::pool::PoolConnection;
 use sqlx::sqlite::SqliteRow;
-use sqlx::{Result, Sqlite};
+use sqlx::{Result, Row, Sqlite};
 
 use super::filter::{Filter, FilterValue};
 use super::order::{CursorDirection, Direction, Order};
@@ -34,6 +35,7 @@ pub async fn fetch_single_row(
     sqlx::query(&query).fetch_one(conn).await
 }
 
+#[allow(clippy::too_many_arguments)]
 pub async fn fetch_multiple_rows(
     conn: &mut PoolConnection<Sqlite>,
     table_name: &str,
@@ -42,14 +44,17 @@ pub async fn fetch_multiple_rows(
     order: &Option<Order>,
     filters: &Option<Vec<Filter>>,
     connection: &ConnectionArguments,
-) -> Result<Vec<SqliteRow>> {
+    total_count: i64,
+) -> Result<(Vec<SqliteRow>, PageInfo)> {
     let mut conditions = build_conditions(keys, filters);
 
+    let mut cursor_param = &connection.after;
     if let Some(after_cursor) = &connection.after {
         conditions.push(handle_cursor(after_cursor, order, CursorDirection::After, id_column)?);
     }
 
     if let Some(before_cursor) = &connection.before {
+        cursor_param = &connection.before;
         conditions.push(handle_cursor(before_cursor, order, CursorDirection::Before, id_column)?);
     }
 
@@ -58,7 +63,18 @@ pub async fn fetch_multiple_rows(
         query.push_str(&format!(" WHERE {}", conditions.join(" AND ")));
     }
 
-    let limit = connection.first.or(connection.last).or(connection.limit).unwrap_or(DEFAULT_LIMIT);
+    let is_cursor_based = connection.first.or(connection.last).is_some() || cursor_param.is_some();
+
+    let data_limit =
+        connection.first.or(connection.last).or(connection.limit).unwrap_or(DEFAULT_LIMIT);
+    let limit = if is_cursor_based {
+        match &cursor_param {
+            Some(_) => data_limit + 2,
+            None => data_limit + 1, // prev page does not exist
+        }
+    } else {
+        data_limit
+    };
 
     // NOTE: Order is determined by the `order` param if provided, otherwise it's inferred from the
     // `first` or `last` param. Explicit ordering take precedence
@@ -89,7 +105,72 @@ pub async fn fetch_multiple_rows(
         query.push_str(&format!(" OFFSET {}", offset));
     }
 
-    sqlx::query(&query).fetch_all(conn).await
+    let mut data = sqlx::query(&query).fetch_all(conn).await?;
+    let mut page_info = PageInfo {
+        has_previous_page: false,
+        has_next_page: false,
+        start_cursor: None,
+        end_cursor: None,
+    };
+
+    if data.is_empty() {
+        Ok((data, page_info))
+    } else if is_cursor_based {
+        let order_field = match order {
+            Some(order) => format!("external_{}", order.field),
+            None => id_column.to_string(),
+        };
+
+        match cursor_param {
+            Some(cursor_query) => {
+                let first_cursor = cursor::encode(
+                    &data[0].try_get::<String, &str>(id_column)?,
+                    &data[0].try_get_unchecked::<String, &str>(&order_field)?,
+                );
+
+                if &first_cursor == cursor_query && data.len() != 1 {
+                    data.remove(0);
+                    page_info.has_previous_page = true;
+                } else {
+                    data.pop();
+                }
+
+                if data.len() as u64 == limit - 1 {
+                    page_info.has_next_page = true;
+                    data.pop();
+                }
+            }
+            None => {
+                if data.len() as u64 == limit {
+                    page_info.has_next_page = true;
+                    data.pop();
+                }
+            }
+        }
+
+        if !data.is_empty() {
+            page_info.start_cursor = Some(cursor::encode(
+                &data[0].try_get::<String, &str>(id_column)?,
+                &data[0].try_get_unchecked::<String, &str>(&order_field)?,
+            ));
+            page_info.end_cursor = Some(cursor::encode(
+                &data[data.len() - 1].try_get::<String, &str>(id_column)?,
+                &data[data.len() - 1].try_get_unchecked::<String, &str>(&order_field)?,
+            ));
+        }
+
+        Ok((data, page_info))
+    } else {
+        let offset = connection.offset.unwrap_or(0);
+        if 1 < offset && offset < total_count as u64 {
+            page_info.has_previous_page = true;
+        }
+        if limit + offset < total_count as u64 {
+            page_info.has_next_page = true;
+        }
+
+        Ok((data, page_info))
+    }
 }
 
 fn handle_cursor(

crates/torii/graphql/src/query/order.rs

@@ -15,8 +15,8 @@ pub struct Order {
 
 #[derive(AsRefStr, Debug, EnumString)]
 pub enum CursorDirection {
-    #[strum(serialize = "<")]
+    #[strum(serialize = "<=")]
     After,
-    #[strum(serialize = ">")]
+    #[strum(serialize = ">=")]
     Before,
 }