some diagnosis

Still todo: real integration tests

src/stream/commander/api.clj

@@ -90,7 +90,7 @@
                                         ;            Error Diagnose           ;
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
-(defn diagnose-error
+(defn diagnose-runtime-error
   "Deduces the problem from the error `message` and the process
   information `proc` and returns it.
 
@@ -122,10 +122,37 @@
 
     :else :unknown))
 
+(defn diagnose-start-error
+  "Deduces the problem from the error `message` and the process
+  information `proc` and returns it.
+
+  The returned codes are:
+    "
+  [message _]
+  (cond
+    (string/includes? message "No such file") :ffmpeg-not-found
+    :else :unknown))
+
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
                                         ;              Monitoring             ;
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
+(defn- handle-process-error!
+  [event id]
+  (when-let [proc (get-process! id)]
+    (let [problem
+          (case (:detail-type event)
+            :nonzero-exit (diagnose-runtime-error (:stderr (:details event)) proc)
+            :start-failed (diagnose-start-error (:message (:details event)) proc)
+            nil)]
+
+      (dosync
+       (alter processes
+              (fn [procs]
+                (let [proc (get procs id)
+                      updated-proc (assoc proc :problems (conj (:problems proc) problem))]
+                  (assoc procs id updated-proc))))))))
+
 (defn- put-process-event!
   [id data]
   (a/put! master-monitor {:type :process-event
@@ -135,12 +162,8 @@
 (defn- handle-status-event!
   "Handles status `event`s from the process with the `id`."
   [id event]
-  (println "------------------------------>" event
-           (case (:type event)
-             :error (when (= :nonzero-exit (:detail-type :nonzero-exit))
-                      (when-let [proc (get-process! id)]
-                        (diagnose-error (:stderr (:details event)) proc)))
-             :else nil))
+  (case (:type event)
+    :error (handle-process-error! event id))
   (put-process-event! id event))
 
 ;; TODO: specs

src/stream/commander/processes.clj

@@ -119,7 +119,7 @@
         (do
           (a/put! status (error-status err
                                        :start-failed
-                                       :stderr err))
+                                       :message err))
           (deliver prom {:success false :error err})
           nil)))))
 

test/stream/commander_test.clj

@@ -27,6 +27,7 @@
   (let [config {:cam-ip "0.0.0.0"
                 :cam-rtsp-port "554"
                 :profile "bla"
+                :ffmpeg-path "nonex"
                 :stream-server "server"
                 :stream-key "key"}]
     ;; TODO: proper spec testing
@@ -41,6 +42,10 @@
       (testing "starting a process (which will fail)"
         (is (not (:success @(p/start! proc)))))
 
+      (testing "problem diagnosis"
+        (is ((:problems (api/get-process! (:id proc)))
+             :ffmpeg-not-found)))
+
       (testing "spilling junk into the monitor channel"
         (a/>!! (:monitor proc) "junk"))