Derive FromQueryResult

README.md

@@ -49,4 +49,4 @@ Balance between compile-time checking and compilation speed.
 
 3. Avoid 'symbol soup'
 
-Avoid procedural macro if possible, use derive macro where appropriate.
+Avoid function-like macros with DSL, use derive macros where appropriate. Be friendly with IDE tools.

examples/sqlx-mysql/src/example_cake.rs

@@ -26,6 +26,16 @@ pub enum Relation {
     Fruit,
 }
 
+impl EntityTrait for Entity {
+    type Model = Model;
+
+    type Column = Column;
+
+    type PrimaryKey = PrimaryKey;
+
+    type Relation = Relation;
+}
+
 impl ColumnTrait for Column {
     type EntityName = Entity;
 

examples/sqlx-mysql/src/example_fruit.rs

@@ -26,6 +26,16 @@ pub enum PrimaryKey {
 #[derive(Copy, Clone, Debug, EnumIter)]
 pub enum Relation {}
 
+impl EntityTrait for Entity {
+    type Model = Model;
+
+    type Column = Column;
+
+    type PrimaryKey = PrimaryKey;
+
+    type Relation = Relation;
+}
+
 impl ColumnTrait for Column {
     type EntityName = Entity;
 

examples/sqlx-mysql/src/main.rs

@@ -1,4 +1,4 @@
-use sea_orm::{ColumnTrait, Database, EntityTrait, QueryErr, QueryHelper};
+use sea_orm::{ColumnTrait, Database, EntityTrait, QueryErr, QueryHelper, FromQueryResult};
 
 mod example_cake;
 mod example_fruit;
@@ -104,26 +104,12 @@ async fn find_one(db: &Database) -> Result<(), QueryErr> {
 }
 
 async fn count_fruits_by_cake(db: &Database) -> Result<(), QueryErr> {
-    #[derive(Debug)]
+    #[derive(Debug, FromQueryResult)]
     struct SelectResult {
         name: String,
         num_of_fruits: i32,
     }
 
-    {
-        // TODO: implement with derive macro
-        use sea_orm::{FromQueryResult, QueryResult, TypeErr};
-
-        impl FromQueryResult for SelectResult {
-            fn from_query_result(row: &QueryResult, pre: &str) -> Result<Self, TypeErr> {
-                Ok(Self {
-                    name: row.try_get(pre, "name")?,
-                    num_of_fruits: row.try_get(pre, "num_of_fruits")?,
-                })
-            }
-        }
-    }
-
     print!("count fruits by cake: ");
 
     let select = cake::Entity::find()

sea-orm-macros/src/derives/entity.rs

@@ -39,15 +39,5 @@ pub fn expend_derive_entity(ident: Ident, attrs: Vec<Attribute>) -> syn::Result<
                 write!(s, "{}", self.as_str()).unwrap();
             }
         }
-
-        impl EntityTrait for #ident {
-            type Model = Model;
-        
-            type Column = Column;
-        
-            type PrimaryKey = PrimaryKey;
-        
-            type Relation = Relation;
-        }
     ))
 }

sea-orm-macros/src/derives/from_query_result.rs

@@ -0,0 +1,42 @@
+use proc_macro2::{Ident, TokenStream};
+use syn::{Data, DataStruct, Field, Fields};
+use quote::{format_ident, quote, quote_spanned};
+
+pub fn expend_derive_from_query_result(ident: Ident, data: Data) -> syn::Result<TokenStream> {
+    let fields = match data {
+        Data::Struct(DataStruct {
+            fields: Fields::Named(named),
+            ..
+        }) => {
+            named.named
+        },
+        _ => return Ok(quote_spanned! {
+            ident.span() => compile_error!("you can only derive DeriveModel on structs");
+        }),
+    };
+
+    let field: Vec<Ident> = fields
+        .into_iter()
+        .map(|Field { ident, .. }| {
+            format_ident!("{}", ident.unwrap().to_string())
+        })
+        .collect();
+
+    let name: Vec<TokenStream> = field
+        .iter()
+        .map(|f| {
+            let s = f.to_string();
+            quote! { #s }
+        })
+        .collect();
+
+    Ok(quote!(
+        impl sea_orm::FromQueryResult for #ident {
+            fn from_query_result(row: &sea_orm::QueryResult, pre: &str) -> Result<Self, sea_orm::TypeErr> {
+                Ok(Self {
+                    #(#field: row.try_get(pre, #name)?),*
+                })
+            }
+        }
+    ))
+}

sea-orm-macros/src/derives/mod.rs

@@ -1,9 +1,11 @@
 mod entity;
+mod from_query_result;
 mod primary_key;
 mod column;
 mod model;
 
 pub use entity::*;
+pub use from_query_result::*;
 pub use primary_key::*;
 pub use column::*;
 pub use model::*;

sea-orm-macros/src/lib.rs

@@ -10,7 +10,7 @@ pub fn derive_entity(input: TokenStream) -> TokenStream {
     let DeriveInput {
         ident, attrs, ..
     } = parse_macro_input!(input);
-    
+
     match derives::expend_derive_entity(ident, attrs) {
         Ok(ts) => ts.into(),
         Err(e) => e.to_compile_error().into(),
@@ -22,7 +22,7 @@ pub fn derive_primary_key(input: TokenStream) -> TokenStream {
     let DeriveInput {
         ident, data, ..
     } = parse_macro_input!(input);
-    
+
     match derives::expend_derive_primary_key(ident, data) {
         Ok(ts) => ts.into(),
         Err(e) => e.to_compile_error().into(),
@@ -34,7 +34,7 @@ pub fn derive_column(input: TokenStream) -> TokenStream {
     let DeriveInput {
         ident, data, ..
     } = parse_macro_input!(input);
-    
+
     match derives::expend_derive_column(ident, data) {
         Ok(ts) => ts.into(),
         Err(e) => e.to_compile_error().into(),
@@ -46,9 +46,21 @@ pub fn derive_model(input: TokenStream) -> TokenStream {
     let DeriveInput {
         ident, data, ..
     } = parse_macro_input!(input);
-    
+
     match derives::expend_derive_model(ident, data) {
         Ok(ts) => ts.into(),
         Err(e) => e.to_compile_error().into(),
     }
+}
+
+#[proc_macro_derive(FromQueryResult)]
+pub fn derive_from_query_result(input: TokenStream) -> TokenStream {
+    let DeriveInput {
+        ident, data, ..
+    } = parse_macro_input!(input);
+
+    match derives::expend_derive_from_query_result(ident, data) {
+        Ok(ts) => ts.into(),
+        Err(e) => e.to_compile_error().into(),
+    }
 }

src/entity/prelude.rs

@@ -1,5 +1,5 @@
 pub use crate::{
     ColumnTrait, ColumnType, EntityName, EntityTrait, EnumIter, Iden, IdenStatic, ModelTrait,
     PrimaryKeyOfModel, PrimaryKeyTrait, QueryResult, Related, RelationDef, RelationTrait, Select,
-    TypeErr, Value, DeriveEntity, DerivePrimaryKey, DeriveColumn, DeriveModel,
+    TypeErr, Value, DeriveEntity, DerivePrimaryKey, DeriveColumn, DeriveModel
 };

src/lib.rs

@@ -20,4 +20,5 @@ pub use sea_orm_macros::{
     DerivePrimaryKey,
     DeriveColumn,
     DeriveModel,
+    FromQueryResult,
 };

src/tests_cfg/cake.rs

@@ -26,6 +26,16 @@ pub enum Relation {
     Fruit,
 }
 
+impl EntityTrait for Entity {
+    type Model = Model;
+
+    type Column = Column;
+
+    type PrimaryKey = PrimaryKey;
+
+    type Relation = Relation;
+}
+
 impl ColumnTrait for Column {
     type EntityName = Entity;
 

src/tests_cfg/fruit.rs

@@ -26,6 +26,16 @@ pub enum PrimaryKey {
 #[derive(Copy, Clone, Debug, EnumIter)]
 pub enum Relation {}
 
+impl EntityTrait for Entity {
+    type Model = Model;
+
+    type Column = Column;
+
+    type PrimaryKey = PrimaryKey;
+
+    type Relation = Relation;
+}
+
 impl ColumnTrait for Column {
     type EntityName = Entity;