♻️ Share Ladybug connection across ingest and stats

backend/src/app/graph/ingest.clj

@@ -40,12 +40,14 @@
           {:keys [statements stats]}
           (project.document/projection-statements data file)
           ingest-statements (conj (into ddl statements) "CHECKPOINT;")]
-      (ladybug/exec! db-path ingest-statements)
-      {:file-id        file-id
-       :revn           (:revn file)
-       :name           (or (:name data) (:name file))
-       :db-path        db-path
-       :schema-version schema/schema-version
-       :projection     {:stats stats}
-       :transforms     (project.transforms/apply-transforms! system db-path data file)
-       :stats          (stats/summarize db-path)})))
+      (ladybug/with-connection! db-path
+        (fn [conn]
+          (ladybug/exec-on-connection! conn ingest-statements)
+          {:file-id        file-id
+           :revn           (:revn file)
+           :name           (or (:name data) (:name file))
+           :db-path        db-path
+           :schema-version schema/schema-version
+           :projection     {:stats stats}
+           :transforms     (project.transforms/apply-transforms! system db-path data file)
+           :stats          (stats/summarize-connection conn)})))))

backend/src/app/graph/ladybug.clj

@@ -91,19 +91,7 @@
               :statement statement
               :err (.getErrorMessage result))))
 
-(defn- with-connection
-  [db-path f]
-  (let [^Database db (if (memory-db-path? db-path)
-                       (Database.)
-                       (Database. (str db-path)))]
-    (try
-      (let [^Connection conn (Connection. db)]
-        (try
-          (f conn)
-          (finally
-            (.close conn))))
-      (finally
-        (.close db)))))
+(def ^:private default-query-timeout-seconds 120)
 
 (defn- scalar-value
   [^Connection conn statement]
@@ -122,36 +110,64 @@
       (with-open [^QueryResult result (.query conn cypher)]
         (check-success! result cypher)))))
 
-(def ^:private default-query-timeout-seconds 120)
+(defn- ensure-db-path!
+  [db-path]
+  (when-not (memory-db-path? db-path)
+    (fs/create-dir (fs/parent db-path))))
+
+(defn with-connection!
+  "Open a Ladybug connection for `db-path` and invoke `(f conn)`.
+
+  For `:memory:`, the database only lives for the duration of this call;
+  all reads and writes must happen inside `f`."
+  [db-path f]
+  (ensure-db-path! db-path)
+  (let [^Database db (if (memory-db-path? db-path)
+                       (Database.)
+                       (Database. (str db-path)))]
+    (try
+      (let [^Connection conn (Connection. db)]
+        (try
+          (.setQueryTimeout conn default-query-timeout-seconds)
+          (f conn)
+          (finally
+            (.close conn))))
+      (finally
+        (.close db)))))
+
+(defn exec-on-connection!
+  "Execute Cypher statements on an open Ladybug connection."
+  [^Connection conn statements]
+  (assert (sequential? statements) "statements should be a sequential collection")
+  (run-statements! conn statements))
+
+(defn query-scalar-on-connection!
+  "Execute a query expected to return a single scalar value on `conn`."
+  [^Connection conn statement]
+  (scalar-value conn statement))
 
 (defn exec!
   "Execute Cypher statements against a Ladybug database.
 
   `db-path` is either `:memory:` or a filesystem path to a `.lbug` database."
   [db-path statements]
-  (assert (sequential? statements) "statements should be a sequential collection")
-  (when-not (memory-db-path? db-path)
-    (fs/create-dir (fs/parent db-path)))
-  (with-connection db-path
-    (fn [^Connection conn]
-      (.setQueryTimeout conn default-query-timeout-seconds)
-      (run-statements! conn statements))))
+  (with-connection! db-path
+    (fn [conn]
+      (exec-on-connection! conn statements))))
 
 (defn query-scalar!
   "Execute a query expected to return a single scalar value."
   [db-path statement]
-  (with-connection db-path
-    (fn [^Connection conn]
-      (.setQueryTimeout conn default-query-timeout-seconds)
-      (scalar-value conn statement))))
+  (with-connection! db-path
+    (fn [conn]
+      (query-scalar-on-connection! conn statement))))
 
 (defn smoke-test!
   "Run a minimal CREATE + count against Ladybug."
   [& {:keys [db-path] :or {db-path ":memory:"}}]
   (when-not (memory-db-path? db-path)
-    (reset-db-path! db-path)
-    (fs/create-dir (fs/parent db-path)))
-  (with-connection db-path
+    (reset-db-path! db-path))
+  (with-connection! db-path
     (fn [^Connection conn]
       (run-statements! conn
                        ["CREATE NODE TABLE Person(name STRING, age INT64, PRIMARY KEY(name));"

backend/src/app/graph/stats.clj

@@ -15,20 +15,25 @@
     (str "`" table "`")
     table))
 
-(defn- count-query
-  [db-path statement]
-  (or (ladybug/query-scalar! db-path statement) 0))
+(defn- count-on-connection
+  [conn statement]
+  (or (ladybug/query-scalar-on-connection! conn statement) 0))
+
+(defn summarize-connection
+  "Return node/edge counts using an open Ladybug connection."
+  [conn]
+  {:nodes (into {}
+                (map (fn [{:keys [name]}]
+                       [name (count-on-connection
+                              conn
+                              (str "MATCH (n:" (node-label-for-match name) ") "
+                                   "RETURN count(n) AS " name "_c;"))])
+                     schema/node-tables))
+   :edges {:IsChildOf (count-on-connection
+                        conn
+                        "MATCH ()-[e:IsChildOf]->() RETURN count(e) AS IsChildOf_c;")}})
 
 (defn summarize
   "Return node/edge counts from the graph database."
   [db-path]
-  {:nodes (into {}
-                (map (fn [{:keys [name]}]
-                       [name (count-query
-                              db-path
-                              (str "MATCH (n:" (node-label-for-match name) ") "
-                                   "RETURN count(n) AS " name "_c;"))])
-                     schema/node-tables))
-   :edges {:IsChildOf (count-query
-                        db-path
-                        "MATCH ()-[e:IsChildOf]->() RETURN count(e) AS IsChildOf_c;")}})
+  (ladybug/with-connection! db-path summarize-connection))

backend/src/app/srepl/main.clj

@@ -431,7 +431,7 @@
   - `:db-path` path or `:memory:`
   - `:reset-db?` delete any existing db first (default true)"
   [file-id & opts]
-  (let [result (graph.ingest/ingest-file! main/system file-id opts)]
+  (let [result (apply graph.ingest/ingest-file! main/system file-id opts)]
     (graph.report/print-ingest! result)
     result))