add FCE examples

sqlite/src/main.rs

@@ -0,0 +1,102 @@
+/*
+ * Copyright 2020 Fluence Labs Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+use fluence::fce;
+use fce_sqlite_connector;
+use fce_sqlite_connector::State;
+
+pub fn main() {}
+
+#[fce]
+pub fn test1(age: i64) {
+    let connection = fce_sqlite_connector::open(":memory:").unwrap();
+
+    connection
+        .execute(
+            "
+            CREATE TABLE users (name TEXT, age INTEGER);
+            INSERT INTO users VALUES ('Alice', 42);
+            INSERT INTO users VALUES ('Bob', 69);
+        ",
+        )
+        .unwrap();
+
+    let mut statement = connection
+        .prepare("SELECT * FROM users WHERE age > ?")
+        .unwrap();
+
+    statement.bind(1, age).unwrap();
+
+    while let State::Row = statement.next().unwrap() {
+        println!("name = {}", statement.read::<String>(0).unwrap());
+        println!("age = {}", statement.read::<i64>(1).unwrap());
+    }
+}
+
+#[fce]
+pub fn test2(age: i64) {
+    use fce_sqlite_connector::Value;
+
+    let connection = fce_sqlite_connector::open(":memory:").unwrap();
+
+    connection
+        .execute(
+            "
+            CREATE TABLE users (name TEXT, age INTEGER);
+            INSERT INTO users VALUES ('Alice', 42);
+            INSERT INTO users VALUES ('Bob', 69);
+        ",
+        )
+        .unwrap();
+
+    let mut cursor = connection
+        .prepare("SELECT * FROM users WHERE age > ?")
+        .unwrap()
+        .cursor();
+
+    cursor.bind(&[Value::Integer(age)]).unwrap();
+
+    while let Some(row) = cursor.next().unwrap() {
+        println!(
+            "name = {}",
+            row[0].as_string().expect("error on row[0] parsing")
+        );
+        println!(
+            "age = {}",
+            row[1].as_integer().expect("error on row[1] parsing")
+        );
+    }
+}
+
+#[fce]
+pub fn test3() {
+    let db_path = "/var/users.sqlite";
+    let connection = fce_sqlite_connector::open(db_path).expect("error on connection establishing");
+
+    let execute_result = connection.execute(
+        "
+            CREATE TABLE users (name TEXT, age INTEGER);
+            INSERT INTO users VALUES ('Alice', 42);
+            INSERT INTO users VALUES ('Bob', 69);
+        ",
+    );
+
+    println!("execute result: {:?}", execute_result);
+
+    //TODO fix it
+    // let file_size = std::fs::metadata(db_path).expect("error on file_size check").len();
+    // println!("{} file size is {}", db_path, file_size);
+}