Review comment: extracted shared go-promise.

addon/src/index.js

@@ -53,49 +53,37 @@ async function findPagesMatching(db, string) {
 }
 
 async function savePage(db, url, title, content) {
-  let txResult = await db.transact([{"db/id": 55,
-                                     "page/title": title,
-                                     "page/url": url
-                                     //                                    "page/starred": true
-  }]);
+  let datom = {"db/id": 55, "page/url": url};
+  if (title) {
+    datom["page/title"] = title;
+  }
+  if (content) {
+    datom["page/content"] = content;
+  }
+  let txResult = await db.transact([datom]);
   return txResult;
 }
 
 async function handleClick(state) {
   let db = await datomish.open("/tmp/testing.db");
   await db.ensureSchema(schema);
+
   let txResult = await savePage(db, tabs.activeTab.url, tabs.activeTab.title, "Content goes here");
+
   console.log("Transaction returned " + JSON.stringify(txResult));
   console.log("Transaction instant: " + txResult.txInstant);
-  let results = await findURLs(db); //datomish.q(db.db(), "[:find ?url :in $ :where [?e :page/url ?url]]");
+
+  let results = await findURLs(db);
   results = results.map(r => r[1]);
+
   console.log("Query results: " + JSON.stringify(results));
+
   let pages = await findPagesMatching(db, "goes");
+
   console.log("Pages: " + JSON.stringify(pages));
   await db.close();
 }
 
-/*
-async function handleClick(state) {
-  console.log("Handling click: " + state);
-  let tab = tabs.activeTab;
-  console.log("Active tab: " + tab);
-  console.log("Active tab: " + tab.url);
-  console.log("Active tab: " + tab.title);
-  let db = await initDB("/tmp/datomish.db");
-  console.log("Opened DB: " + db);
-  await savePage(db, tab.url, tab.title, "Content goes here.");
-  console.log("Saved page.");
-
-  let urls = await findURLs(db);
-  console.log("URLs: " + JSON.stringify(urls));
-
-  let results = await findPagesMatching(db, "goes");
-  console.log("Pages: " + JSON.stringify(results));
-  await db.close();
-}
-*/
-
 var button = buttons.ActionButton({
   id: "datomish-save",
   label: "Save Page",

src/common/datomish/js.cljs

@@ -5,7 +5,8 @@
 (ns datomish.js
   (:refer-clojure :exclude [])
   (:require-macros
-     [datomish.pair-chan :refer [go-pair <?]])
+     [datomish.pair-chan :refer [go-pair <?]]
+     [datomish.promises :refer [go-promise]])
   (:require
      [cljs.core.async :as a :refer [take! <! >!]]
      [cljs.reader]
@@ -14,23 +15,12 @@
      [datomish.db :as db]
      [datomish.db-factory :as db-factory]
      [datomish.pair-chan]
+     [datomish.promises :refer [take-pair-as-promise!]]
      [datomish.sqlite :as sqlite]
      [datomish.simple-schema :as simple-schema]
      [datomish.js-sqlite :as js-sqlite]
      [datomish.transact :as transact]))
 
-(defn- take-pair-as-promise! [ch f]
-  ;; Just like take-as-promise!, but aware that it's handling a pair channel.
-  ;; Also converts values, if desired.
-  (promise
-    (fn [resolve reject]
-      (letfn [(split-pair [[v e]]
-                (if e
-                  (do
-                    (println "Got error:" e)
-                    (reject e))
-                  (resolve (f v))))]
-        (cljs.core.async/take! ch split-pair)))))
 
 ;; Public API.
 
@@ -40,13 +30,9 @@
 (defn ^:export q [db find options]
   (let [find (cljs.reader/read-string find)
         opts (cljify options)]
-    (println "Running query " (pr-str find) (pr-str {:foo find}) (pr-str opts))
     (take-pair-as-promise!
-      (go-pair
-        (let [res (<? (db/<?q db find opts))]
-          (println "Got results: " (pr-str res))
-          (clj->js res)))
-      identity)))
+      (db/<?q db find opts)
+      clj->js)))
 
 (defn ^:export ensure-schema [conn simple-schema]
   (let [simple-schema (cljify simple-schema)
@@ -67,27 +53,23 @@
   (try
     (let [tx-data (js->tx-data tx-data)]
       (println "Transacting:" (pr-str tx-data))
-      (take-pair-as-promise!
-        (go-pair
+      (go-promise clj->js
         (let [tx-result (<? (transact/<transact! conn tx-data))]
           (select-keys tx-result
                        [:tempids
                         :added-idents
                         :added-attributes
                         :tx
-                          :txInstant])))
-        clj->js))
+                        :txInstant]))))
     (catch js/Error e
       (println "Error in transact:" e))))
 
 (defn ^:export open [path]
   ;; Eventually, URI.  For now, just a plain path (no file://).
-  (take-pair-as-promise!
-    (go-pair
+  (go-promise clj->js
     (let [conn (<? (sqlite/<sqlite-connection path))
           db (<? (db-factory/<db-with-sqlite-connection conn))]
       (let [c (transact/connection-with-db db)]
-          (clj->js
         ;; We pickle the connection as a thunk here so it roundtrips through JS
         ;; without incident.
         {:conn (fn [] c)
@@ -98,4 +80,3 @@
          :close (fn [] (db/close-db db))
          :toString (fn [] (str "#<DB " path ">"))
          :path path}))))
-    identity))

src/common/datomish/promises.cljc

@@ -0,0 +1,30 @@
+(ns datomish.promises
+  #?(:cljs
+     (:require-macros
+        [datomish.pair-chan :refer [go-pair <?]]))
+  (:require
+     #?@(:clj [[datomish.pair-chan :refer [go-pair]]
+               [clojure.core.async :as a :refer [take!]]])
+     #?@(:cljs [[cljs-promises.core :refer [promise]]
+                [cljs.core.async :as a :refer [take!]]])))
+
+(defn take-pair-as-promise!
+  "Just like take-as-promise!, but aware that it's handling a pair channel.
+   Also converts values, if desired."
+  ([ch]
+   (take-pair-as-promise! ch identity))
+  ([ch f]
+    (promise
+      (fn [resolve reject]
+        (take!
+          ch
+          (fn [[v e]]
+            (if e
+              (reject e)
+              (resolve (f v)))))))))
+
+(defmacro go-promise [f & body]
+  `(datomish.promises/take-pair-as-promise!
+     (datomish.pair-chan/go-pair
+       ~@body)
+     ~f))