implement #17

Author: NyxCode

example-postgres/src/main.rs

@@ -55,7 +55,11 @@ async fn main() -> anyhow::Result<()> {
 
     log::info!("use the improved query macro for searching users");
     let search_result = query2::query_users(&db, Some("NewFirstName"), None).await?;
-    println!("{:?}", search_result);
+    log::info!("search result: {:?}", search_result);
+
+    log::info!("load all users in the order specified by the 'order_by' attribute");
+    let all = User::all_paginated(&db, 0, 100).await?;
+    log::info!("all users: {all:?}");
 
     log::info!("delete the user from the database");
     new.delete(&db).await?;
@@ -64,7 +68,7 @@ async fn main() -> anyhow::Result<()> {
 }
 
 #[derive(Debug, ormx::Table)]
-#[ormx(table = "users", id = user_id, insertable, deletable)]
+#[ormx(table = "users", id = user_id, insertable, deletable, order_by = "email ASC")]
 struct User {
     // map this field to the column "id"
     #[ormx(column = "id")]

ormx-macros/src/attrs.rs

@@ -13,6 +13,8 @@ pub enum TableAttr {
     Insertable(Option<Insertable>),
     // deletable
     Deletable(()),
+    // order_by = <string>
+    OrderBy(String),
 }
 
 pub struct Insertable {
@@ -144,7 +146,8 @@ impl_parse!(TableAttr {
     "table" => Table(= String),
     "id" => Id(= Ident),
     "insertable" => Insertable((= Insertable)?),
-    "deletable" => Deletable()
+    "deletable" => Deletable(),
+    "order_by" => OrderBy(= String)
 });
 
 impl_parse!(TableFieldAttr {

ormx-macros/src/backend/common/table.rs

@@ -101,7 +101,15 @@ fn update<B: Backend>(table: &Table<B>) -> TokenStream {
 
 fn stream_all<B: Backend>(table: &Table<B>, column_list: &str) -> TokenStream {
     let return_type = crate::utils::stream!(sqlx::Result<Self>);
-    let all_sql = format!("SELECT {} FROM {}", column_list, table.name());
+    let order_by = match &table.order_by {
+        None => &format!("{} DESC", table.id.column()),
+        Some(by) => by,
+    };
+    let all_sql = format!(
+        "SELECT {} FROM {} ORDER BY {order_by}",
+        column_list,
+        table.name()
+    );
 
     quote! {
         fn stream_all<'a, 'c: 'a>(
@@ -116,8 +124,12 @@ fn stream_all<B: Backend>(table: &Table<B>, column_list: &str) -> TokenStream {
 fn stream_all_paginated<B: Backend>(table: &Table<B>, column_list: &str) -> TokenStream {
     let return_type = crate::utils::stream!(sqlx::Result<Self>);
     let mut bindings = B::Bindings::default();
+    let order_by = match &table.order_by {
+        None => &format!("{} DESC", table.id.column()),
+        Some(by) => by,
+    };
     let all_sql = format!(
-        "SELECT {} FROM {} LIMIT {} OFFSET {}",
+        "SELECT {} FROM {} ORDER BY {order_by} LIMIT {} OFFSET {} ",
         column_list,
         table.name(),
         bindings.next().unwrap(),

ormx-macros/src/lib.rs

@@ -1,4 +1,9 @@
-#![cfg(any(feature = "mysql", feature = "postgres", feature = "sqlite", feature = "mariadb"))]
+#![cfg(any(
+    feature = "mysql",
+    feature = "postgres",
+    feature = "sqlite",
+    feature = "mariadb"
+))]
 
 mod attrs;
 mod backend;

ormx-macros/src/table/mod.rs

@@ -20,6 +20,7 @@ pub struct Table<B: Backend> {
     pub fields: Vec<TableField<B>>,
     pub insertable: Option<Insertable>,
     pub deletable: bool,
+    pub order_by: Option<String>,
 }
 
 #[derive(Clone)]
@@ -70,7 +71,12 @@ impl<B: Backend> TableField<B> {
         let q = B::QUOTE;
 
         if self.custom_type {
-            format!("{q}{}{q} AS {q}{}: {}{q}", self.column_name, self.field.to_string(), self.ty.to_token_stream())
+            format!(
+                "{q}{}{q} AS {q}{}: {}{q}",
+                self.column_name,
+                self.field.to_string(),
+                self.ty.to_token_stream()
+            )
         } else if self.field == self.column_name {
             self.column()
         } else {

ormx-macros/src/table/parse.rs

@@ -1,8 +1,8 @@
 use std::{convert::TryFrom, marker::PhantomData};
 
 use proc_macro2::Span;
-use syn::{Data, DeriveInput, Error, Ident, Result};
-use syn::ext::IdentExt;
+use syn::{ext::IdentExt, Data, DeriveInput, Error, Ident, Result};
+
 use super::{Table, TableField};
 use crate::{
     attrs::{parse_attrs, Insertable, TableAttr, TableFieldAttr},
@@ -40,7 +40,8 @@ impl<B: Backend> TryFrom<&syn::Field> for TableField<B> {
                 TableFieldAttr::GetOptional(g) => set_once(&mut get_optional, g)?,
                 TableFieldAttr::GetMany(g) => set_once(&mut get_many, g)?,
                 TableFieldAttr::Set(s) => {
-                    let default = || Ident::new(&format!("set_{}", ident.unraw()), Span::call_site());
+                    let default =
+                        || Ident::new(&format!("set_{}", ident.unraw()), Span::call_site());
                     set_once(&mut set, s.unwrap_or_else(default))?
                 }
                 TableFieldAttr::Default(..) => set_once(&mut default, true)?,
@@ -80,7 +81,7 @@ impl<B: Backend> TryFrom<&DeriveInput> for Table<B> {
             .map(TableField::try_from)
             .collect::<Result<Vec<_>>>()?;
 
-        none!(table, id, insertable, deletable);
+        none!(table, id, insertable, deletable, order_by);
         for attr in parse_attrs::<TableAttr>(&value.attrs)? {
             match attr {
                 TableAttr::Table(x) => set_once(&mut table, x)?,
@@ -93,6 +94,7 @@ impl<B: Backend> TryFrom<&DeriveInput> for Table<B> {
                     set_once(&mut insertable, x.unwrap_or_else(default))?;
                 }
                 TableAttr::Deletable(_) => set_once(&mut deletable, true)?,
+                TableAttr::OrderBy(by) => set_once(&mut order_by, by)?,
             }
         }
 
@@ -123,6 +125,7 @@ impl<B: Backend> TryFrom<&DeriveInput> for Table<B> {
             insertable,
             fields,
             deletable: deletable.unwrap_or(false),
+            order_by,
         })
     }
 }

ormx/src/lib.rs

@@ -1,4 +1,9 @@
-#![cfg(any(feature = "mysql", feature = "postgres", feature = "sqlite", feature = "mariadb"))]
+#![cfg(any(
+    feature = "mysql",
+    feature = "postgres",
+    feature = "sqlite",
+    feature = "mariadb"
+))]
 //! Lightweight derive macros for bringing orm-like features to sqlx.
 //!
 //! # Example: Table
@@ -80,23 +85,33 @@ where
     ) -> impl Future<Output = Result<Self>> + Send + 'a;
 
     /// Stream all rows from this table.
+    /// By default, results are ordered in descending order according to their ID column.
+    /// This can be configured using `#[ormx(order_by = "some_column ASC")]`.
     fn stream_all<'a, 'c: 'a>(
         db: impl Executor<'c, Database = Db> + 'a,
     ) -> impl Stream<Item = Result<Self>> + Send + 'a;
 
+    /// Streams at most `limit` rows from this table, skipping the first `offset` rows.
+    /// By default, results are ordered in descending order according to their ID column.
+    /// This can be configured using `#[ormx(order_by = "some_column ASC")]`.
     fn stream_all_paginated<'a, 'c: 'a>(
         db: impl Executor<'c, Database = Db> + 'a,
         offset: i64,
         limit: i64,
     ) -> impl Stream<Item = Result<Self>> + Send + 'a;
 
     /// Load all rows from this table.
+    /// By default, results are ordered in descending order according to their ID column.
+    /// This can be configured using `#[ormx(order_by = "some_column ASC")]`.
     fn all<'a, 'c: 'a>(
         db: impl Executor<'c, Database = Db> + 'a,
     ) -> impl Future<Output = Result<Vec<Self>>> + Send + 'a {
         Self::stream_all(db).try_collect()
     }
 
+    /// Load at most `limit` rows from this table, skipping the first `offset`.
+    /// By default, results are ordered in descending order according to their ID column.
+    /// This can be configured using `#[ormx(order_by = "some_column ASC")]`.
     fn all_paginated<'a, 'c: 'a>(
         db: impl Executor<'c, Database = Db> + 'a,
         offset: i64,