Experimenting with returning tempids

src/com/example/app.cljs

@@ -6,6 +6,7 @@
 
 (defn global-eql-transform
   [ast]
+  (println "global-eql-transform: AST = " ast)
   (-> ast
       (app/default-global-eql-transform)
       ;; Make sure that if Pathom sends ::p/errors, Fulcro does not remove it:

src/com/example/mock_server.cljs

@@ -14,12 +14,13 @@
          transmit! (:transmit! (mock-http-server {:parser (fn [req] (parser env req))}))]
      {:transmit! (fn [this send-node]
                    (js/setTimeout ; simulate some network delay, for fun
-                    #(transmit! this send-node
+                    #(transmit! this
                                 (update send-node
                                         ::txn/result-handler
                                         (fn [handler]
-                                          (fn logging-wrapper [res] (println "MOCK SERVER RESULT>" res)
-                                            (handler res)))))
+                                          (fn logging-wrapper [res] 
+                                            (println "MOCK SERVER RESULT> " res)
+                                            (when handler (handler res))))))
                     100))}))
   ([]
    (mock-remote {})))

src/com/example/mutations.cljs

@@ -5,9 +5,15 @@
    `#?(:clj ...)` but here even the 'server' runs in the browser so we must
    define them in another ns, which we do in `...pathom`."
   (:require
-   [com.fulcrologic.fulcro.mutations :refer [defmutation]]))
+   [com.fulcrologic.fulcro.mutations :as m :refer [defmutation]]
+   [com.fulcrologic.fulcro.raw.components :as rc]))
 
 (defmutation create-random-thing [{:keys [tmpid]}]
   (action [{:keys [state] :as env}]
           (swap! state assoc-in [:new-thing tmpid] {:id tmpid, :txt "A new thing!"}))
+  ;(remote [_] true)
+  (remote [env] true (m/returning env (rc/nc '[:fake]))))
+
+
+(defmutation failing-mut [_]
   (remote [_] true))

src/com/example/pathom.cljs

@@ -33,14 +33,21 @@
   (println "SERVER: Simulate creating a new thing with real DB id 123" tmpid)
   {:tempids {tmpid 123}})
 
+(pc/defmutation failing-mut [_ _]
+  {::pc/sym 'com.example.mutations/failing-mut}
+  (throw (ex-info "The failing mutation always fails" {:doomed? true})))
+
 (def my-resolvers-and-mutations 
   "Add any resolvers you make to this list (and reload to re-create the parser)"
-  [index-explorer create-random-thing i-fail])
+  [index-explorer i-fail 
+   create-random-thing failing-mut])
 
 (defn new-parser 
   "Create a new Pathom parser with the necessary settings"
   []
-  (p/parallel-parser
+  ;; NOTE: By default use `parser` in Clojure and `async-parser` in the 1-threaded JS
+  ;;       (so that you can call e.g. js/fetch and return its result via core.async)
+  (p/async-parser 
     {::p/env     {::p/reader [p/map-reader
                               pc/parallel-reader
                               pc/open-ident-reader]

src/com/example/ui.cljs

@@ -2,6 +2,7 @@
   (:require 
     [com.example.mutations :as mut]
     [com.fulcrologic.fulcro.algorithms.merge :as merge]
+    [com.fulcrologic.fulcro.mutations :as m]
     [com.fulcrologic.fulcro.algorithms.tempid :as tempid]
     [com.fulcrologic.fulcro.algorithms.data-targeting :as targeting]
     [com.fulcrologic.fulcro.algorithms.normalized-state :as norm]
@@ -11,19 +12,30 @@
     [com.fulcrologic.fulcro.dom :as dom :refer [button div form h1 h2 h3 input label li ol p ul]]))
 
 (defsc Root [this props]
-  {:query [[df/marker-table :load-progress] :new-thing]}
+  {:query [[df/marker-table :load-progress] :new-thing ::m/mutation-error]}
   (div
-   (p "Hello from the ui/Root component!")
-   (div {:style {:border "1px dashed", :margin "1em", :padding "1em"}}
-    (p "Invoke a load! that fails and display the error:")
-    (when-let [m (get props [df/marker-table :load-progress])]
-      (dom/p "Progress marker: " (str m)))
-    (button {:onClick #(df/load! this :i-fail (rc/nc '[*]) {:marker :load-progress})} "I fail!"))
-   (div {:style {:border "1px dashed", :margin "1em", :padding "1em"}}
-    (p "Simulate creating a new thing with server-assigned ID, leveraging Fulcro's tempid support:")
-    (button {:onClick #(let [tmpid (tempid/tempid)]
-                         (comp/transact! this [(mut/create-random-thing {:tmpid tmpid})]))}
-            "I create!")
-    (when-let [things (:new-thing props)]
-      (p (str "Created a thing with the ID: " (first (keys things))))))))
+    (p "Hello from the ui/Root component!")
+    ;; Load fail
+    (div {:style {:border "1px dashed", :margin "1em", :padding "1em"}}
+      (p "Invoke a load! that fails and display the error:")
+      (when-let [m (get props [df/marker-table :load-progress])]
+        (dom/p "Progress marker: " (str m)))
+      (button {:onClick #(df/load! this :i-fail (rc/nc '[*])
+                           {:marker :load-progress})} 
+        "I fail to load!"))
+    ;; Mutate: fail
+    (div {:style {:border "1px dashed", :margin "1em", :padding "1em"}}
+      (p "Invoke a *mutation* that fails:")
+      (button {:onClick #(comp/transact! this [(mut/failing-mut)])} 
+        "I fail to mutate!"))
+    ;; Mutate: create new
+    (div {:style {:border "1px dashed", :margin "1em", :padding "1em"}}
+      (p "Simulate creating a new thing with server-assigned ID, leveraging Fulcro's tempid support:")
+      (button {:onClick #(let [tmpid (tempid/tempid)]
+                           (comp/transact! this [(mut/create-random-thing {:tmpid tmpid})]))}
+        "I create!")
+      (when-let [err (::m/mutation-error props)] ; FIXME must fix :remote-error? to mark the err as err
+        (p {:style {:color :red}} (str "The mutation failed: " err)))
+      (when-let [things (:new-thing props)]
+        (p (str "Created a thing with the ID: " (first (keys things))))))))