Inspect (#27)

* inspect middleware

* add dep types

* fix

* remove nil

* change API

* add links

* cond-> -> into+filter

* Add doc for inspect

Co-authored-by: KGOH <[email protected]>

---------

Co-authored-by: KGOH <[email protected]>

Author: darkleaf

notebooks/index.clj

@@ -91,6 +91,7 @@
   #_[:li [:a {:href (clerk/doc-url "test/darkleaf/di/tutorial/x_instrument_test.clj")} "Instrument"]]
   [:li [:a {:href (clerk/doc-url "test/darkleaf/di/tutorial/x_update_key_test.clj")} "Update key"]]
   [:li [:a {:href (clerk/doc-url "test/darkleaf/di/tutorial/x_log_test.clj")} "Log"]]
+  [:li [:a {:href (clerk/doc-url "test/darkleaf/di/tutorial/x_inspect_test.clj")} "Inspect"]]
   [:li [:a {:href (clerk/doc-url "test/darkleaf/di/tutorial/y_graceful_stop_test.clj")} "Graceful stop"]]
   [:li [:a {:href (clerk/doc-url "test/darkleaf/di/tutorial/y_multi_arity_service_test.clj")} "Multi arity service"]]
   [:li [:a {:href (clerk/doc-url "test/darkleaf/di/tutorial/z_multi_system_test.clj")} "Multi system"]]
@@ -118,6 +119,7 @@
 ;; ### `darkleaf.di.core`
 (view-doc #'di/start)
 (view-doc #'di/stop)
+(view-doc #'di/inspect)
 (view-doc #'di/ref)
 (view-doc #'di/opt-ref)
 (view-doc #'di/template)

src/darkleaf/di/core.clj

@@ -829,3 +829,42 @@
             (p/demolish factory obj)
             (after-demolish! {:key key :object obj})
             nil))))))
+
+
+(defn- inspect-middleware []
+  (fn [registry]
+    (fn [key]
+      (let [factory       (registry key)
+            declared-deps (p/dependencies factory)
+            info          (into {}
+                                (filter (fn [[k v]] (some? v)))
+                                {:key          key
+                                 :dependencies declared-deps})]
+        (reify p/Factory
+          (dependencies [_]
+            declared-deps)
+          (build [_ deps]
+            (into [info]
+                  (comp
+                   (mapcat val)
+                   (distinct))
+                  deps))
+          (demolish [_ obj]))))))
+
+(defn inspect
+  "Collects and returns a vector of keys along with their dependencies.
+  Useful for inspecting enabled components and services.
+  Evaluates all registries with middlewares applied.
+
+  Expects the same arguments as `start` and returns a vector of keys with dependencies e.g.:
+
+  ```clojure
+  [{:key `root :dependencies {`foo :required `bar :optional}}
+   {:key `foo}
+   {:key `bar}]
+  ```"
+  [key & middlewares]
+  (with-open [components (start key
+                                middlewares
+                                (inspect-middleware))]
+    @components))

test/darkleaf/di/tutorial/x_inspect_test.clj

@@ -0,0 +1,21 @@
+(ns darkleaf.di.tutorial.x-inspect-test
+  (:require
+   [clojure.test :as t]
+   [darkleaf.di.core :as di]))
+
+(defn a []
+  :ok)
+
+(defn b [{a `a}]
+  :ok)
+
+(defn c [{a   `a
+          b   `b
+          :or {b :default}}]
+  :ok)
+
+(t/deftest ok
+  (t/is (= [{:key `c :dependencies {`a :required `b :optional}}
+            {:key `a}
+            {:key `b :dependencies {`a :required}}]
+           (di/inspect `c))))