update todo examples to 0.4 and use migrations

* update tests/x.py

 * add examples/x.py

examples/sqlite/todos/README.md

@@ -1,27 +1,41 @@
 # TODOs Example
 
+## Setup
+
+1. Declare the database URL
+
+    ```
+    export DATABASE_URL="sqlite:todos.db"
+    ```
+
+2. Create the database.
+
+    ```
+    $ sqlx db create
+    ```
+
+3. Run sql migrations
+
+    ```
+    $ sqlx migrate run
+    ```
+
 ## Usage
 
-Declare the database URL:
+Add a todo 
 
 ```
-export DATABASE_URL="sqlite:///path/to/this/directory/todos.db"
+cargo run -- add "todo description"
 ```
 
-Create the database:
+Complete a todo.
 
 ```
-sqlite3 todos.db
+cargo run -- done <todo id>
 ```
 
-Load the database schema (using the SQLite CLI interface opened from the previous command):
+List all todos
 
 ```
-sqlite> .read schema.sql
+cargo run
 ```
-
-Use `.exit` to leave the SQLite CLI. Then, to run this example:
-
-- Add a todo: `cargo run -- add "todo description"`
-- Complete a todo: `cargo run -- done <todo id>`
-- List all todos: `cargo run`

examples/sqlite/todos/migrations/20200718111257_todos.sql

@@ -0,0 +1,6 @@
+CREATE TABLE IF NOT EXISTS todos
+(
+    id          INTEGER PRIMARY KEY NOT NULL,
+    description TEXT                NOT NULL,
+    done        BOOLEAN             NOT NULL DEFAULT 0
+);

examples/sqlite/todos/schema.sql

@@ -1,5 +0,0 @@
-CREATE TABLE IF NOT EXISTS todos (
-    id          INTEGER PRIMARY KEY NOT NULL,
-    description TEXT NOT NULL,
-    done        BOOLEAN NOT NULL DEFAULT 0
-);

examples/sqlite/todos/src/main.rs

@@ -1,5 +1,5 @@
-use anyhow::Context;
-use sqlx::SqlitePool;
+use sqlx::sqlite::SqlitePool;
+use sqlx::Done;
 use std::env;
 use structopt::StructOpt;
 
@@ -18,10 +18,7 @@ enum Command {
 #[async_std::main]
 #[paw::main]
 async fn main(args: Args) -> anyhow::Result<()> {
-    let pool = SqlitePool::new(
-        &env::var("DATABASE_URL").context("`DATABASE_URL` must be set to run this example")?,
-    )
-    .await?;
+    let pool = SqlitePool::connect(&env::var("DATABASE_URL")?).await?;
 
     match args.cmd {
         Some(Command::Add { description }) => {
@@ -49,22 +46,19 @@ async fn main(args: Args) -> anyhow::Result<()> {
 async fn add_todo(pool: &SqlitePool, description: String) -> anyhow::Result<i64> {
     let mut conn = pool.acquire().await?;
 
-    // Insert the TODO, then obtain the ID of this row
-    sqlx::query!(
+    // Insert the task, then obtain the ID of this row
+    let id = sqlx::query!(
         r#"
 INSERT INTO todos ( description )
-VALUES ( $1 )
+VALUES ( ?1 )
         "#,
         description
     )
     .execute(&mut conn)
-    .await?;
+    .await?
+    .last_insert_rowid();
 
-    let rec: (i64,) = sqlx::query_as("SELECT last_insert_rowid()")
-        .fetch_one(&mut conn)
-        .await?;
-
-    Ok(rec.0)
+    Ok(id)
 }
 
 async fn complete_todo(pool: &SqlitePool, id: i64) -> anyhow::Result<bool> {
@@ -72,12 +66,13 @@ async fn complete_todo(pool: &SqlitePool, id: i64) -> anyhow::Result<bool> {
         r#"
 UPDATE todos
 SET done = TRUE
-WHERE id = $1
+WHERE id = ?1
         "#,
         id
     )
     .execute(pool)
-    .await?;
+    .await?
+    .rows_affected();
 
     Ok(rows_affected > 0)
 }