Comment posting is idempotent + tests

src/routes/admin/newsletters.rs

@@ -1,5 +1,4 @@
 use crate::{
-    authentication::AuthenticatedUser,
     idempotency::{IdempotencyKey, save_response, try_processing},
     routes::{AdminError, AppError},
     startup::AppState,
@@ -8,7 +7,7 @@ use crate::{
 use anyhow::Context;
 use askama::Template;
 use axum::{
-    Extension, Form,
+    Form,
     extract::State,
     response::{Html, IntoResponse, Response},
 };
@@ -95,7 +94,6 @@ pub async fn publish_newsletter(
         base_url,
         ..
     }): State<AppState>,
-    Extension(AuthenticatedUser { user_id, .. }): Extension<AuthenticatedUser>,
     Form(form): Form<BodyData>,
 ) -> Result<Response, AppError> {
     validate_form(&form).map_err(|e| AdminError::Publish(anyhow::anyhow!(e)))?;
@@ -105,7 +103,7 @@ pub async fn publish_newsletter(
         .try_into()
         .map_err(AdminError::Idempotency)?;
 
-    let mut transaction = match try_processing(&connection_pool, &idempotency_key, user_id).await? {
+    let mut transaction = match try_processing(&connection_pool, &idempotency_key).await? {
         crate::idempotency::NextAction::StartProcessing(t) => t,
         crate::idempotency::NextAction::ReturnSavedResponse(response) => {
             return Ok(response);
@@ -129,7 +127,7 @@ pub async fn publish_newsletter(
     let message = String::from("Your email has been queued for delivery.");
     let template = MessageTemplate::success(message);
     let response = Html(template.render().unwrap()).into_response();
-    let response = save_response(transaction, &idempotency_key, user_id, response)
+    let response = save_response(transaction, &idempotency_key, response)
         .await
         .map_err(AdminError::UnexpectedError)?;
     Ok(response)

src/routes/admin/posts.rs

@@ -54,7 +54,7 @@ pub async fn create_post(
         .try_into()
         .map_err(AdminError::Idempotency)?;
 
-    let mut transaction = match try_processing(&connection_pool, &idempotency_key, user_id).await? {
+    let mut transaction = match try_processing(&connection_pool, &idempotency_key).await? {
         crate::idempotency::NextAction::StartProcessing(t) => t,
         crate::idempotency::NextAction::ReturnSavedResponse(response) => {
             return Ok(response);
@@ -75,7 +75,7 @@ pub async fn create_post(
 
     let template = MessageTemplate::success("Your new post has been published!".into());
     let response = Html(template.render().unwrap()).into_response();
-    let response = save_response(transaction, &idempotency_key, user_id, response)
+    let response = save_response(transaction, &idempotency_key, response)
         .await
         .map_err(AdminError::UnexpectedError)?;
     Ok(response)

src/routes/comments.rs

@@ -1,4 +1,5 @@
-use crate::routes::get_max_page;
+use crate::idempotency::{IdempotencyKey, save_response, try_processing};
+use crate::routes::{AdminError, get_max_page};
 use crate::templates::CommentsPageDashboardTemplate;
 use crate::{
     domain::CommentEntry,
@@ -13,7 +14,7 @@ use axum::{
     extract::{Path, Query, State},
     response::{IntoResponse, Response},
 };
-use sqlx::PgPool;
+use sqlx::{Executor, PgPool, Postgres, Transaction};
 use uuid::Uuid;
 
 #[derive(serde::Deserialize)]
@@ -25,6 +26,7 @@ pub struct CommentPathParam {
 pub struct CommentForm {
     pub author: Option<String>,
     pub content: String,
+    pub idempotency_key: String,
 }
 
 #[tracing::instrument(name = "Posting new comment", skip_all, fields(post_id = %post_id))]
@@ -36,14 +38,29 @@ pub async fn post_comment(
     Form(form): Form<CommentForm>,
 ) -> Result<Response, AppError> {
     validate_form(&form)?;
-    let comment_id = insert_comment(&connection_pool, post_id, form)
+
+    let idempotency_key: IdempotencyKey = form
+        .idempotency_key
+        .try_into()
+        .map_err(AdminError::Idempotency)?;
+
+    let mut transaction = match try_processing(&connection_pool, &idempotency_key).await? {
+        crate::idempotency::NextAction::StartProcessing(t) => t,
+        crate::idempotency::NextAction::ReturnSavedResponse(response) => {
+            return Ok(response);
+        }
+    };
+
+    insert_comment(&mut transaction, post_id, form.author, form.content)
         .await
         .context("Could not insert comment into database.")?;
-    tracing::info!("new comment with id {} has been inserted", comment_id);
+
     let template = HtmlTemplate(MessageTemplate::success(
         "Your comment has been posted.".into(),
     ));
-    Ok(template.into_response())
+    let response = template.into_response();
+    let response = save_response(transaction, &idempotency_key, response).await?;
+    Ok(response)
 }
 
 fn validate_form(form: &CommentForm) -> Result<(), anyhow::Error> {
@@ -55,17 +72,19 @@ fn validate_form(form: &CommentForm) -> Result<(), anyhow::Error> {
 
 #[tracing::instrument(name = "Inserting new comment in database", skip_all, fields(comment_id = tracing::field::Empty))]
 async fn insert_comment(
-    connection_pool: &PgPool,
+    transaction: &mut Transaction<'static, Postgres>,
     post_id: Uuid,
-    form: CommentForm,
+    author: Option<String>,
+    content: String,
 ) -> Result<Uuid, sqlx::Error> {
-    let author = form
-        .author
+    let author = author
         .filter(|s| !s.trim().is_empty())
         .map(|s| s.trim().to_string());
+    let content = content.trim();
+
     let comment_id = Uuid::new_v4();
     tracing::Span::current().record("comment_id", comment_id.to_string());
-    sqlx::query!(
+    let query = sqlx::query!(
         "
         INSERT INTO comments (comment_id, post_id, author, content)
         VALUES ($1, $2, $3, $4)
@@ -73,10 +92,9 @@ async fn insert_comment(
         comment_id,
         post_id,
         author,
-        form.content.trim()
-    )
-    .execute(connection_pool)
-    .await?;
+        content,
+    );
+    transaction.execute(query).await?;
     Ok(comment_id)
 }
 

src/routes/posts.rs

@@ -151,9 +151,11 @@ pub async fn see_post(
         let comments = get_comments_page_for_post(&connection_pool, post_id, 1)
             .await
             .context("Failed to fetch latest comments")?;
+        let idempotency_key = Uuid::new_v4().to_string();
         let template = HtmlTemplate(PostTemplate {
             post,
             comments,
+            idempotency_key,
             current_page,
             max_page,
             comments_count,