Reorganize and consolidate HTTP routes.

HTTP routes are now defined in a single, unified module, pulling them out of the topical modules they were formerly part of.

This is intended to improve the navigability of the codebase. Previously, finding the handler corresponding to a specific endpoint required prior familiarity, though in practice you could usually guess from topic area. Now, all routes are defined in one place; if you know the path, you can read down the list to find the handler.

Handlers themselves live with the domain they are most appropriately "part of," generally (in this version, universally) in a `handlers` submodule. The handlers themselves have been flattened down; rather than representing a path and a method, they now represent a named operation (which is suspiciously similar to the path in most cases). This means that we no longer have constructs like `crate::ui::routes::ch::channel` - it's now `crate::ui::handlers::channel` instead.

## Disclaimer

I Solemnly Swear I Didn't Change Any Handlers.

## Prior art

I've inadvertently reinvented Django's `urls.py` convention, and I've opted to lean into that.

Merges flatter-routes-reorg into main.

1 files changed, 273 insertions, 0 deletions

diff --git a/src/event/handlers/stream/test/channel.rs b/src/event/handlers/stream/test/channel.rs
new file mode 100644
index 0000000..187c3c3
--- /dev/null
+++ b/src/event/handlers/stream/test/channel.rs
@@ -0,0 +1,273 @@
+use axum::extract::State;
+use axum_extra::extract::Query;
+use futures::{future, stream::StreamExt as _};
+
+use crate::test::fixtures::{self, future::Expect as _};
+
+#[tokio::test]
+async fn creating() {
+    // Set up the environment
+
+    let app = fixtures::scratch_app().await;
+    let resume_point = fixtures::boot::resume_point(&app).await;
+
+    // Subscribe
+
+    let subscriber = fixtures::identity::create(&app, &fixtures::now()).await;
+    let super::Response(events) = super::handler(
+        State(app.clone()),
+        subscriber,
+        None,
+        Query(super::QueryParams { resume_point }),
+    )
+    .await
+    .expect("subscribe never fails");
+
+    // Create a channel
+
+    let name = fixtures::channel::propose();
+    let channel = app
+        .channels()
+        .create(&name, &fixtures::now())
+        .await
+        .expect("creating a channel succeeds");
+
+    // Verify channel created event
+
+    events
+        .filter_map(fixtures::event::channel)
+        .filter_map(fixtures::event::channel::created)
+        .filter(|event| future::ready(event.channel == channel))
+        .next()
+        .expect_some("channel created event is delivered")
+        .await;
+}
+
+#[tokio::test]
+async fn previously_created() {
+    // Set up the environment
+
+    let app = fixtures::scratch_app().await;
+    let resume_point = fixtures::boot::resume_point(&app).await;
+
+    // Create a channel
+
+    let name = fixtures::channel::propose();
+    let channel = app
+        .channels()
+        .create(&name, &fixtures::now())
+        .await
+        .expect("creating a channel succeeds");
+
+    // Subscribe
+
+    let subscriber = fixtures::identity::create(&app, &fixtures::now()).await;
+    let super::Response(events) = super::handler(
+        State(app.clone()),
+        subscriber,
+        None,
+        Query(super::QueryParams { resume_point }),
+    )
+    .await
+    .expect("subscribe never fails");
+
+    // Verify channel created event
+
+    let _ = events
+        .filter_map(fixtures::event::channel)
+        .filter_map(fixtures::event::channel::created)
+        .filter(|event| future::ready(event.channel == channel))
+        .next()
+        .expect_some("channel created event is delivered")
+        .await;
+}
+
+#[tokio::test]
+async fn expiring() {
+    // Set up the environment
+
+    let app = fixtures::scratch_app().await;
+    let channel = fixtures::channel::create(&app, &fixtures::ancient()).await;
+    let resume_point = fixtures::boot::resume_point(&app).await;
+
+    // Subscribe
+
+    let subscriber = fixtures::identity::create(&app, &fixtures::now()).await;
+    let super::Response(events) = super::handler(
+        State(app.clone()),
+        subscriber,
+        None,
+        Query(super::QueryParams { resume_point }),
+    )
+    .await
+    .expect("subscribe never fails");
+
+    // Expire channels
+
+    app.channels()
+        .expire(&fixtures::now())
+        .await
+        .expect("expiring channels always succeeds");
+
+    // Check for expiry event
+    let _ = events
+        .filter_map(fixtures::event::channel)
+        .filter_map(fixtures::event::channel::deleted)
+        .filter(|event| future::ready(event.id == channel.id))
+        .next()
+        .expect_some("a deleted channel event will be delivered")
+        .await;
+}
+
+#[tokio::test]
+async fn previously_expired() {
+    // Set up the environment
+
+    let app = fixtures::scratch_app().await;
+    let channel = fixtures::channel::create(&app, &fixtures::ancient()).await;
+    let resume_point = fixtures::boot::resume_point(&app).await;
+
+    // Expire channels
+
+    app.channels()
+        .expire(&fixtures::now())
+        .await
+        .expect("expiring channels always succeeds");
+
+    // Subscribe
+
+    let subscriber = fixtures::identity::create(&app, &fixtures::now()).await;
+    let super::Response(events) = super::handler(
+        State(app.clone()),
+        subscriber,
+        None,
+        Query(super::QueryParams { resume_point }),
+    )
+    .await
+    .expect("subscribe never fails");
+
+    // Check for expiry event
+    let _ = events
+        .filter_map(fixtures::event::channel)
+        .filter_map(fixtures::event::channel::deleted)
+        .filter(|event| future::ready(event.id == channel.id))
+        .next()
+        .expect_some("a deleted channel event will be delivered")
+        .await;
+}
+
+#[tokio::test]
+async fn deleting() {
+    // Set up the environment
+
+    let app = fixtures::scratch_app().await;
+    let channel = fixtures::channel::create(&app, &fixtures::now()).await;
+    let resume_point = fixtures::boot::resume_point(&app).await;
+
+    // Subscribe
+
+    let subscriber = fixtures::identity::create(&app, &fixtures::now()).await;
+    let super::Response(events) = super::handler(
+        State(app.clone()),
+        subscriber,
+        None,
+        Query(super::QueryParams { resume_point }),
+    )
+    .await
+    .expect("subscribe never fails");
+
+    // Delete the channel
+
+    app.channels()
+        .delete(&channel.id, &fixtures::now())
+        .await
+        .expect("deleting a valid channel succeeds");
+
+    // Check for delete event
+    let _ = events
+        .filter_map(fixtures::event::channel)
+        .filter_map(fixtures::event::channel::deleted)
+        .filter(|event| future::ready(event.id == channel.id))
+        .next()
+        .expect_some("a deleted channel event will be delivered")
+        .await;
+}
+
+#[tokio::test]
+async fn previously_deleted() {
+    // Set up the environment
+
+    let app = fixtures::scratch_app().await;
+    let channel = fixtures::channel::create(&app, &fixtures::now()).await;
+    let resume_point = fixtures::boot::resume_point(&app).await;
+
+    // Delete the channel
+
+    app.channels()
+        .delete(&channel.id, &fixtures::now())
+        .await
+        .expect("deleting a valid channel succeeds");
+
+    // Subscribe
+
+    let subscriber = fixtures::identity::create(&app, &fixtures::now()).await;
+    let super::Response(events) = super::handler(
+        State(app.clone()),
+        subscriber,
+        None,
+        Query(super::QueryParams { resume_point }),
+    )
+    .await
+    .expect("subscribe never fails");
+
+    // Check for expiry event
+    let _ = events
+        .filter_map(fixtures::event::channel)
+        .filter_map(fixtures::event::channel::deleted)
+        .filter(|event| future::ready(event.id == channel.id))
+        .next()
+        .expect_some("a deleted channel event will be delivered")
+        .await;
+}
+
+#[tokio::test]
+async fn previously_purged() {
+    // Set up the environment
+
+    let app = fixtures::scratch_app().await;
+    let channel = fixtures::channel::create(&app, &fixtures::ancient()).await;
+    let resume_point = fixtures::boot::resume_point(&app).await;
+
+    // Delete and purge the channel
+
+    app.channels()
+        .delete(&channel.id, &fixtures::ancient())
+        .await
+        .expect("deleting a valid channel succeeds");
+
+    app.channels()
+        .purge(&fixtures::now())
+        .await
+        .expect("purging channels always succeeds");
+
+    // Subscribe
+
+    let subscriber = fixtures::identity::create(&app, &fixtures::now()).await;
+    let super::Response(events) = super::handler(
+        State(app.clone()),
+        subscriber,
+        None,
+        Query(super::QueryParams { resume_point }),
+    )
+    .await
+    .expect("subscribe never fails");
+
+    // Check for expiry event
+    events
+        .filter_map(fixtures::event::channel)
+        .filter_map(fixtures::event::channel::deleted)
+        .filter(|event| future::ready(event.id == channel.id))
+        .next()
+        .expect_wait("deleted channel events not delivered")
+        .await;
+}