From 8406f31be2ba3397734c76eb03d0143779e43484 Mon Sep 17 00:00:00 2001
From: James Reeves <jreeves@weavejester.com>
Date: Tue, 7 Jan 2025 22:59:05 +0000
Subject: [PATCH] Replace :default-handler with :handlers option

---
 README.md                        | 18 +++++++++++++++---
 src/duct/handler/reitit.clj      |  6 ++++++
 src/duct/router/reitit.clj       |  4 ++--
 test/duct/router/reitit_test.clj | 14 ++++++++------
 4 files changed, 31 insertions(+), 11 deletions(-)
 create mode 100644 src/duct/handler/reitit.clj

diff --git a/README.md b/README.md
index 19877a0..8f23844 100644
--- a/README.md
+++ b/README.md
@@ -36,7 +36,7 @@ There are four top level options available:
 - `:routes` - the Reitit routing data
 - `:middleware` - a vector of middleware to apply to the Ring handler
 - `:data` - data to add to every Reitit route
-- `:default-handler` - a default handlers for error conditions
+- `:handlers` - a vector of handlers to fall back
 
 The `:data` key takes a map and acts as it does in Reitit, except for
 the following keys:
@@ -46,13 +46,25 @@ the following keys:
 
 These keys will automatically add relevant middleware.
 
-The `:default-handler` key holds a map that takes the same keys as the
-Reitit `create-default-handler` function:
+The `:duct.handler.reitit/default` key will initiate into a handler
+using the Reitit `create-default-handler` function. It takes the
+following options:
 
 - `:not-found` - a handler for 404 HTTP errors
 - `:method-not-allowed` - a handler for 405 HTTP errors
 - `:not-acceptable` - a handler for 406 HTTP errors
 
+This can be referenced in the `:handlers` vector to provide a default
+handler:
+
+```edn
+{:duct.router/reitit
+ {:routes   ["/" {:get #ig/ref :example.handler/root}]
+  :handlers [#ig/ref :duct.handler.reitit/default]}
+ :duct.handler.reitit/default {}
+ :example.handler/root {}}
+```
+
 ## License
 
 Copyright © 2024 James Reeves
diff --git a/src/duct/handler/reitit.clj b/src/duct/handler/reitit.clj
new file mode 100644
index 0000000..df6c10c
--- /dev/null
+++ b/src/duct/handler/reitit.clj
@@ -0,0 +1,6 @@
+(ns duct.handler.reitit
+  (:require [integrant.core :as ig]
+            [reitit.ring :as ring]))
+
+(defmethod ig/init-key ::default [_ opts]
+  (ring/create-default-handler opts))
diff --git a/src/duct/router/reitit.clj b/src/duct/router/reitit.clj
index 92ab72f..66b30d4 100644
--- a/src/duct/router/reitit.clj
+++ b/src/duct/router/reitit.clj
@@ -52,6 +52,6 @@
                    (update-data convert-coercion)
                    (update-data convert-muuntaja))
         router (ring/router (:routes opts) opts)]
-    (if-some [handler (:default-handler opts)]
-      (ring/ring-handler router (ring/create-default-handler handler) opts)
+    (if-some [handlers (seq (:handlers opts))]
+      (ring/ring-handler router (apply ring/routes handlers) opts)
       (ring/ring-handler router opts))))
diff --git a/test/duct/router/reitit_test.clj b/test/duct/router/reitit_test.clj
index f5b77fc..f69aaf9 100644
--- a/test/duct/router/reitit_test.clj
+++ b/test/duct/router/reitit_test.clj
@@ -1,7 +1,8 @@
 (ns duct.router.reitit-test
   (:require [clojure.test :refer [deftest is]]
             [integrant.core :as ig]
-            [duct.router.reitit :as reitit]))
+            [duct.router.reitit]
+            [duct.handler.reitit]))
 
 (deftest hierarchy-test
   (ig/load-hierarchy)
@@ -50,11 +51,12 @@
         {:duct.router/reitit
          {:routes {"/"    {:get {:handler handler}}
                    "/406" {:handler (constantly nil)}}
-          :default-handler
-          {:not-found (constantly {:status 404, :body "404"})
-           :method-not-allowed (constantly {:status 405, :body "405"})
-           :not-acceptable (constantly {:status 406, :body "406"})}}}
-        router  (:duct.router/reitit (ig/init config))]
+          :handlers [(ig/ref :duct.handler.reitit/default)]}
+         :duct.handler.reitit/default
+         {:not-found (constantly {:status 404, :body "404"})
+          :method-not-allowed (constantly {:status 405, :body "405"})
+          :not-acceptable (constantly {:status 406, :body "406"})}}
+        router (:duct.router/reitit (ig/init config))]
     (is (= {:status 200, :body "Hello World"}
            (router {:request-method :get, :uri "/"})))
     (is (= {:status 404, :body "404"}