v orm: select

vlib/orm/orm_test.v

@@ -1,6 +1,6 @@
-import os
+//import os
-import pg
+//import pg
-import term
+//import term
 import sqlite
 
 struct Modules {
@@ -11,30 +11,48 @@ struct Modules {
 	//nr_downloads int
 }
 
+struct User {
+	id int
+	name string
+}
+
 fn test_orm_sqlite() {
 	db := sqlite.connect(':memory:') or { panic(err) }
-	/*
+	db.exec("drop table if exists User")
-	db.exec("drop table if exists users")
+	db.exec("create table User (id integer primary key, name text default '');")
-	db.exec("create table users (id integer primary key, name text default '');")
 
-	db.exec("insert into users (name) values ('Sam')")
+	name := 'sam'
-	db.exec("insert into users (name) values ('Peter')")
+
-	db.exec("insert into users (name) values ('Kate')")
+	db.exec("insert into User (name) values ('Sam')")
-	nr_users := sql db {
+	db.exec("insert into User (name) values ('Peter')")
-		//select count from modules
+	db.exec("insert into User (name) values ('Kate')")
+	nr_all_users := sql db {
+		select count from User
 	}
-	assert nr_users == 3
+	assert nr_all_users == 3
-	println('nr_users=')
+	println('nr_all_users=$nr_all_users')
-	println(nr_users)
+	//
-	//nr_modules := db.select count from modules
+	nr_users1 := sql db {
-	//nr_modules := db.select count from Modules where id == 1
+		select count from User where id == 1
-	//nr_modules := db.select count from Modules where
+	}
-		//name == 'Bob' && id == 1
+	assert nr_users1 == 1
-	*/
+	println('nr_users1=$nr_users1')
+	//
+	nr_peters := sql db {
+		select count from User where id == 2 && name == 'Peter'
+	}
+	assert nr_peters == 1
+	println('nr_peters=$nr_peters')
+	//
+	nr_sams := sql db {
+		select count from User where id == 1 && name == name
+	}
+	println('nr_sams=$nr_sams')
 }
 
 
 fn test_orm_pg() {
+/*
 	dbname := os.getenv('VDB_NAME')
 	dbuser := os.getenv('VDB_USER')
 	if dbname == '' || dbuser == '' {
@@ -43,8 +61,7 @@ fn test_orm_pg() {
 	}
 	db := pg.connect(dbname: dbname, user: dbuser) or { panic(err) }
 	_ = db
-/*
+	nr_modules := db.select count from modules
-	//nr_modules := db.select count from modules
 	//nr_modules := db.select count from Modules where id == 1
 	nr_modules := db.select count from Modules where
 		name == 'Bob' && id == 1
@@ -61,6 +78,7 @@ fn test_orm_pg() {
 
 /*
 	mod := db.retrieve<Module>(1)
+	mod := db.select from Module where id = 1
 
 	mod := db.update Module set name = name + '!' where id > 10
 

vlib/sqlite/sqlite.v

@@ -37,6 +37,21 @@ pub fn connect(path string) ?DB {
 	}
 }
 
+// Only for V ORM
+fn (db DB) init_stmt(query string) &C.sqlite3_stmt {
+	stmt := &C.sqlite3_stmt(0)
+	C.sqlite3_prepare_v2(db.conn, query.str, -1, &stmt, 0)
+	return stmt
+}
+
+// Only for V ORM
+fn get_int_from_stmt(stmt &C.sqlite3_stmt) int {
+	C.sqlite3_step(stmt)
+	res := C.sqlite3_column_int(stmt, 0)
+	C.sqlite3_finalize(stmt)
+	return res
+}
+
 // Returns a single cell with value int.
 pub fn (db DB) q_int(query string) int {
 	stmt := &C.sqlite3_stmt(0)

vlib/strings/builder.c.v

@@ -49,6 +49,24 @@ pub fn (mut b Builder) go_back(n int) {
 	b.len -= n
 }
 
+pub fn (mut b Builder) cut_last(n int) string {
+	buf := b.buf[b.len-n..]
+	s := string(buf.clone())
+	b.buf.trim(b.buf.len-n)
+	b.len -= n
+	return s
+}
+
+/*
+pub fn (mut b Builder) cut_to(pos int) string {
+	buf := b.buf[pos..]
+	s := string(buf.clone())
+	b.buf.trim(pos)
+	b.len = pos
+	return s
+}
+*/
+
 pub fn (mut b Builder) go_back_to(pos int) {
 	b.buf.trim(pos)
 	b.len = pos

vlib/strings/builder_test.v

@@ -8,11 +8,25 @@ fn test_sb() {
 	assert sb.len == 8
 	assert sb.str() == 'hi!hello'
 	assert sb.len == 0
+	///
 	sb = strings.new_builder(10)
 	sb.write('a')
 	sb.write('b')
 	assert sb.len == 2
 	assert sb.str() == 'ab'
+	///
+	sb = strings.new_builder(10)
+	sb.write('123456')
+	assert sb.cut_last(2) == '56'
+	assert sb.str() == '1234'
+	///
+	/*
+	sb = strings.new_builder(10)
+	sb.write('123456')
+	x := sb.cut_to(2)
+	assert x == '456'
+	assert sb.str() == '123'
+	*/
 }
 
 const (

vlib/term/term.v

@@ -61,6 +61,10 @@ pub fn header(text, divider string) string {
 }
 
 fn supports_escape_sequences(fd int) bool {
+	//println('TERM=' + os.getenv('TERM'))
+	if os.getenv('TERM') == 'dumb' {
+		return false
+	}
 	vcolors_override := os.getenv('VCOLORS')
 	if vcolors_override == 'always' {
 		return true

vlib/v/ast/ast.v

@@ -801,7 +801,13 @@ pub:
 }
 
 pub struct SqlExpr {
+pub:
 	typ         table.Type
+	is_count    bool
+	db_var_name string // `db` in `sql db {`
+	table_name  string
+	where_expr Expr
+	has_where bool
 }
 
 [inline]

vlib/v/checker/checker.v

@@ -556,7 +556,8 @@ pub fn (mut c Checker) infix_expr(mut infix_expr ast.InfixExpr) table.Type {
 				c.error('$infix_expr.op.str(): type `${typ_sym.name}` does not exist', type_expr.pos)
 			}
 			if left.kind != .interface_ && left.kind != .sum_type {
-				c.error('`$infix_expr.op.str()` can only be used with interfaces and sum types', type_expr.pos)
+				c.error('`$infix_expr.op.str()` can only be used with interfaces and sum types',
+					type_expr.pos)
 			}
 			return table.bool_type
 		}
@@ -681,9 +682,12 @@ fn (mut c Checker) check_map_and_filter(is_map bool, elem_typ table.Type, call_e
 		ast.AnonFn {
 			if it.decl.args.len > 1 {
 				c.error('function needs exactly 1 argument', call_expr.pos)
-			} else if is_map && (it.decl.return_type != elem_typ || it.decl.args[0].typ != elem_typ) {
+			} else if is_map && (it.decl.return_type != elem_typ || it.decl.args[0].typ !=
-				c.error('type mismatch, should use `fn(a $elem_sym.name) $elem_sym.name {...}`', call_expr.pos)
+				elem_typ) {
-			} else if !is_map && (it.decl.return_type != table.bool_type || it.decl.args[0].typ != elem_typ) {
+				c.error('type mismatch, should use `fn(a $elem_sym.name) $elem_sym.name {...}`',
+					call_expr.pos)
+			} else if !is_map && (it.decl.return_type != table.bool_type || it.decl.args[0].typ !=
+				elem_typ) {
 				c.error('type mismatch, should use `fn(a $elem_sym.name) bool {...}`', call_expr.pos)
 			}
 		}
@@ -696,9 +700,12 @@ fn (mut c Checker) check_map_and_filter(is_map bool, elem_typ table.Type, call_e
 				if func.args.len > 1 {
 					c.error('function needs exactly 1 argument', call_expr.pos)
 				} else if is_map && (func.return_type != elem_typ || func.args[0].typ != elem_typ) {
-					c.error('type mismatch, should use `fn(a $elem_sym.name) $elem_sym.name {...}`', call_expr.pos)
+					c.error('type mismatch, should use `fn(a $elem_sym.name) $elem_sym.name {...}`',
-				} else if !is_map && (func.return_type != table.bool_type || func.args[0].typ != elem_typ) {
+						call_expr.pos)
-					c.error('type mismatch, should use `fn(a $elem_sym.name) bool {...}`', call_expr.pos)
+				} else if !is_map && (func.return_type != table.bool_type || func.args[0].typ !=
+					elem_typ) {
+					c.error('type mismatch, should use `fn(a $elem_sym.name) bool {...}`',
+						call_expr.pos)
 				}
 			}
 		}
@@ -1948,15 +1955,29 @@ pub fn (mut c Checker) expr(node ast.Expr) table.Type {
 		ast.None {
 			return table.none_type
 		}
+		ast.OrExpr {
+			// never happens
+			return table.void_type
+		}
 		ast.ParExpr {
 			return c.expr(it.expr)
 		}
+		ast.RangeExpr {
+			// never happens
+			return table.void_type
+		}
 		ast.SelectorExpr {
 			return c.selector_expr(mut it)
 		}
 		ast.SizeOf {
 			return table.u32_type
 		}
+		ast.SqlExpr {
+			if it.has_where {
+				c.expr(it.where_expr)
+			}
+			return it.typ
+		}
 		ast.StringLiteral {
 			if it.language == .c {
 				return table.byteptr_type
@@ -1986,12 +2007,6 @@ pub fn (mut c Checker) expr(node ast.Expr) table.Type {
 			}
 			return table.bool_type
 		}
-		else {
-			tnode := typeof(node)
-			if tnode != 'unknown v.ast.Expr' {
-				println('checker.expr(): unhandled node with typeof(`${tnode}`)')
-			}
-		}
 	}
 	return table.void_type
 }

vlib/v/gen/cgen.v

@@ -66,6 +66,7 @@ mut:
 	options              strings.Builder // `Option_xxxx` types
 	json_forward_decls   strings.Builder // json type forward decls
 	enum_typedefs        strings.Builder // enum types
+	sql_buf              strings.Builder // for writing exprs to args via `sqlite3_bind_int()` etc
 	file                 ast.File
 	fn_decl              &ast.FnDecl // pointer to the FnDecl we are currently inside otherwise 0
 	last_fn_c_name       string
@@ -76,6 +77,7 @@ mut:
 	is_assign_rhs        bool // inside right part of assign after `=` (val expr)
 	is_array_set         bool
 	is_amp               bool // for `&Foo{}` to merge PrefixExpr `&` and StructInit `Foo{}`; also for `&byte(0)` etc
+	is_sql               bool // Inside `sql db{}` statement, generating sql instead of C (e.g. `and` instead of `&&` etc)
 	optionals            []string // to avoid duplicates TODO perf, use map
 	inside_ternary       int // ?: comma separated statements on a single line
 	ternary_names        map[string]string
@@ -102,6 +104,8 @@ mut:
 	fn_main              &ast.FnDecl // the FnDecl of the main function. Needed in order to generate the main function code *last*
 	cur_fn               &ast.FnDecl
 	cur_generic_type     table.Type // `int`, `string`, etc in `foo<T>()`
+	sql_i                int
+	sql_stmt_name        string
 }
 
 const (
@@ -131,6 +135,7 @@ pub fn cgen(files []ast.File, table &table.Table, pref &pref.Preferences) string
 		options: strings.new_builder(100)
 		json_forward_decls: strings.new_builder(100)
 		enum_typedefs: strings.new_builder(100)
+		sql_buf: strings.new_builder(100)
 		table: table
 		pref: pref
 		fn_decl: 0
@@ -1566,7 +1571,7 @@ fn (mut g Gen) expr(node ast.Expr) {
 			g.write('sizeof($styp)')
 		}
 		ast.SqlExpr {
-			g.write('// sql expression')
+			g.sql_expr(it)
 		}
 		ast.StringLiteral {
 			if it.is_raw {
@@ -1630,10 +1635,6 @@ fn (mut g Gen) expr(node ast.Expr) {
 			g.expr(it.expr)
 			g.write(')')
 		}
-		//else {
-			// #printf("node=%d\n", node.typ);
-			//println(term.red('cgen.expr(): bad node ' + typeof(node)))
-		//}
 	}
 }
 
@@ -3173,6 +3174,15 @@ fn (mut g Gen) insert_before_stmt(s string) {
 	g.write(cur_line)
 }
 
+fn (mut g Gen) write_expr_to_string(expr ast.Expr) string {
+	pos := g.out.buf.len
+	g.expr(expr)
+	return g.out.cut_last(g.out.buf.len - pos)
+}
+
+fn (mut g Gen) start_tmp() {
+}
+
 // If user is accessing the return value eg. in assigment, pass the variable name.
 // If the user is not using the optional return value. We need to pass a temp var
 // to access its fields (`.ok`, `.error` etc)
@@ -3263,7 +3273,6 @@ fn (mut g Gen) in_optimization(left ast.Expr, right ast.ArrayInit) {
 			ptr_typ := g.gen_array_equality_fn(right.elem_type)
 			g.write('${ptr_typ}_arr_eq(')
 		}
-
 		g.expr(left)
 		if is_str || is_array {
 			g.write(', ')
@@ -4208,7 +4217,6 @@ fn (mut g Gen) array_init(it ast.ArrayInit) {
 	if it.exprs.len == 0 {
 		elem_sym := g.table.get_type_symbol(it.elem_type)
 		is_default_array := elem_sym.kind == .array && it.has_default
-
 		if is_default_array {
 			g.write('__new_array_with_array_default(')
 		} else {

vlib/v/gen/sql.v

@@ -0,0 +1,93 @@
+// Copyright (c) 2019-2020 Alexander Medvednikov. All rights reserved.
+// Use of this source code is governed by an MIT license
+// that can be found in the LICENSE file.
+module gen
+
+import v.ast
+import strings
+
+// pg,mysql etc
+const (
+	dbtype = 'sqlite'
+)
+
+fn (mut g Gen) sql_expr(node ast.SqlExpr) {
+	g.sql_i = 0
+	/*
+	`nr_users := sql db { ... }` =>
+	```
+	sql_init_stmt()
+	sql_bind_int()
+	sql_bind_string()
+	...
+	int nr_users = get_int(stmt)
+	```
+	*/
+	cur_line := g.go_before_stmt(0)
+	mut q := 'select '
+	if node.is_count {
+		// select count(*) from User
+		q += 'count(*) from $node.table_name'
+	}
+	if node.has_where {
+		q += ' where '
+	}
+	// g.write('${dbtype}__DB_q_int(*(${dbtype}__DB*)${node.db_var_name}.data, tos_lit("$q')
+	g.sql_stmt_name = g.new_tmp_var()
+	db_name := g.new_tmp_var()
+	g.writeln('\n\t// sql')
+	g.write('${dbtype}__DB $db_name = *(${dbtype}__DB*)${node.db_var_name}.data;')
+	g.write('sqlite3_stmt* $g.sql_stmt_name = ${dbtype}__DB_init_stmt(*(${dbtype}__DB*)${node.db_var_name}.data, tos_lit("$q')
+	if node.has_where && node.where_expr is ast.InfixExpr {
+		g.expr_to_sql(node.where_expr)
+	}
+	g.writeln('"));')
+	// Dump all sql parameters generated by our custom expr handler
+	binds := g.sql_buf.str()
+	g.sql_buf = strings.new_builder(100)
+	g.writeln(binds)
+	g.writeln('puts(sqlite3_errmsg(${db_name}.conn));')
+	g.writeln('$cur_line ${dbtype}__get_int_from_stmt($g.sql_stmt_name);')
+}
+
+fn (mut g Gen) expr_to_sql(expr ast.Expr) {
+	// Custom handling for infix exprs (since we need e.g. `and` instead of `&&` in SQL queries),
+	// strings. Everything else (like numbers, a.b) is handled by g.expr()
+	//
+	// TODO `where id = some_column + 1` needs literal generation of `some_column` as a string,
+	// not a V variable. Need to distinguish column names from V variables.
+	match expr {
+		ast.InfixExpr {
+			g.expr_to_sql(it.left)
+			match it.op {
+				.eq { g.write(' = ') }
+				.and { g.write(' and ') }
+				else {}
+			}
+			g.expr_to_sql(it.right)
+		}
+		ast.StringLiteral {
+			// g.write("'$it.val'")
+			g.inc_sql_i()
+			g.sql_buf.writeln('sqlite3_bind_text($g.sql_stmt_name, $g.sql_i, "$it.val", $it.val.len, 0);')
+		}
+		ast.IntegerLiteral {
+			g.inc_sql_i()
+			g.sql_buf.writeln('sqlite3_bind_int($g.sql_stmt_name, $g.sql_i, $it.val);')
+		}
+		else {
+			g.expr(expr)
+		}
+	}
+	/*
+	ast.Ident {
+			g.write('$it.name')
+		}
+		else {}
+	*/
+}
+
+fn (mut g Gen) inc_sql_i() {
+	g.sql_i++
+	g.write('?$g.sql_i')
+}

vlib/v/parser/sql.v

@@ -4,7 +4,76 @@
 module parser
 
 import v.ast
+import v.table
 
 fn (mut p Parser) sql_expr() ast.SqlExpr {
-	return ast.SqlExpr{}
+	// `sql db {`
+	p.check_name()
+	db_var_name := p.check_name()
+	p.check(.lcbr)
+	//
+	p.check(.key_select)
+	n := p.check_name()
+	is_count := n == 'count'
+	mut typ := table.void_type
+	if is_count {
+		p.check_name() // from
+		typ = table.int_type
+	}
+	table_type := p.parse_type() // `User`
+	sym := p.table.get_type_symbol(table_type)
+	table_name := sym.name
+	mut where_expr := ast.Expr{}
+	has_where := p.tok.kind == .name && p.tok.lit == 'where'
+	if has_where {
+		p.next()
+		where_expr = p.expr(0)
+	}
+	p.check(.rcbr)
+	// /////////
+	// Register this type's fields as variables so they can be used in `where`
+	// expressions
+	// fields := typ.fields.filter(typ == 'string' || typ == 'int')
+	// fields := typ.fields
+	// get only string and int fields
+	// mut fields := []Var
+	info := sym.info as table.Struct
+	fields := info.fields.filter(it.typ in [table.string_type, table.int_type, table.bool_type])
+	/*
+	for i, field in info.fields {
+        if !(field.typ in ['string', 'int', 'bool']) {
+                println('orm: skipping $field.name')
+                continue
+        }
+        if field.attr.contains('skip') {
+                continue
+        }
+        fields << field
+}
+	*/
+	if fields.len == 0 {
+		p.error('V orm: select: empty fields in `$table_name`')
+	}
+	if fields[0].name != 'id' {
+		p.error('V orm: `id int` must be the first field in `$table_name`')
+	}
+	for field in fields {
+		// println('registering sql field var $field.name')
+		p.scope.register(field.name, ast.Var{
+			name: field.name
+			typ: field.typ
+			is_mut: true
+			is_used: true
+			is_changed: true
+		})
+	}
+	// ////////////
+	return ast.SqlExpr{
+		is_count: is_count
+		typ: typ
+		db_var_name: db_var_name
+		table_name: table_name
+		where_expr: where_expr
+		has_where: has_where
+	}
 }