fix(examples): issues in preferred-crates

Author: abonander

examples/postgres/preferred-crates/src/main.rs

@@ -34,7 +34,7 @@ async fn main() -> anyhow::Result<()> {
     uses_rust_decimal::create_table(&mut conn).await?;
     uses_time::create_table(&mut conn).await?;
 
-    let user_id = sqlx::query!(
+    let user_id = sqlx::query_scalar!(
         "insert into users(username, password_hash) values($1, $2) returning id",
         "user_foo",
         "<pretend this is a password hash>",
@@ -46,6 +46,8 @@ async fn main() -> anyhow::Result<()> {
         .fetch_one(&mut conn)
         .await?;
 
+    println!("Created user: {user:?}");
+
     let session =
         uses_time::create_session(&mut conn, SessionData { user_id }, SESSION_DURATION).await?;
 
@@ -62,5 +64,7 @@ async fn main() -> anyhow::Result<()> {
         .await?
         .expect("expected purchase");
 
+    println!("Created purchase: {purchase:?}");
+
     Ok(())
 }

examples/postgres/preferred-crates/uses-rust-decimal/src/lib.rs

@@ -1,8 +1,8 @@
 use chrono::{DateTime, Utc};
 use sqlx::PgExecutor;
 
-#[derive(sqlx::FromRow)]
-struct Purchase {
+#[derive(sqlx::FromRow, Debug)]
+pub struct Purchase {
     pub id: Uuid,
     pub user_id: Uuid,
     pub amount: Decimal,
@@ -21,7 +21,7 @@ pub async fn create_table(e: impl PgExecutor<'_>) -> sqlx::Result<()> {
                 user_id uuid not null, \
                 amount numeric not null check(amount > 0), \
                 description text not null, \
-                created_at timestamptz not null \
+                created_at timestamptz not null default now() \
              );
         ",
     )
@@ -37,12 +37,14 @@ pub async fn create_purchase(
     amount: Decimal,
     description: &str,
 ) -> sqlx::Result<Uuid> {
-    sqlx::query_scalar("insert into purchases(user_id, amount, description) values ($1, $2, $3)")
-        .bind(user_id)
-        .bind(amount)
-        .bind(description)
-        .fetch_one(e)
-        .await
+    sqlx::query_scalar(
+        "insert into purchases(user_id, amount, description) values ($1, $2, $3) returning id",
+    )
+    .bind(user_id)
+    .bind(amount)
+    .bind(description)
+    .fetch_one(e)
+    .await
 }
 
 pub async fn get_purchase(e: impl PgExecutor<'_>, id: Uuid) -> sqlx::Result<Option<Purchase>> {

examples/postgres/preferred-crates/uses-time/src/lib.rs

@@ -37,7 +37,12 @@ pub async fn create_session<D: Serialize>(
     data: D,
     valid_duration: Duration,
 ) -> sqlx::Result<Session<D>> {
-    let created_at = OffsetDateTime::now_utc();
+    // Round down to the nearest second because
+    // Postgres doesn't support precision higher than 1 microsecond anyway.
+    let created_at = OffsetDateTime::now_utc()
+        .replace_nanosecond(0)
+        .expect("0 nanoseconds should be in range");
+
     let expires_at = created_at + valid_duration;
 
     let id: Uuid = sqlx::query_scalar(