moves to txn

TODO.md

@@ -1,4 +1,6 @@
 * Logging: For debugging.  For runtime monitoring.  For warning of dangerous actions.
+* Connection pooling for Sql implementations
+* Better transactions (i.e. use savepoints)
 * Website?
 * Indexes:
     * Riak: currently indexes ALL fields.  That's inefficient.

sql/spec/hyperion/sql/jdbc_spec.clj

@@ -19,6 +19,10 @@
   (count (execute-query
     (make-query "SELECT * FROM test"))))
 
+(defn do-query [query]
+  (execute-write
+    (make-query query)))
+
 (describe "JDBC Adapter"
   (with connection-url "jdbc:sqlite:")
   (around [it]
@@ -33,17 +37,28 @@
 
     (it "rolls back all changes"
       (rollback
-        (execute-write
-          (make-query "INSERT INTO test (name, age) VALUES ('Myles', 23)")))
-        (should= 0 (test-count)))
+        (do-query "INSERT INTO test (name, age) VALUES ('Myles', 23)")
+        (should= 1 (test-count)))
+      (should= 0 (test-count)))
 
     (it "resets auto commit to its previous value"
       (.setAutoCommit (connection) true)
       (try
         (rollback
           (throw (Exception.)))
         (catch Exception _))
-      (should (.getAutoCommit (connection)))))
+      (should (.getAutoCommit (connection))))
+
+    (it "rolls back multiple"
+      (rollback
+        (do-query "INSERT INTO test (name, age) VALUES ('Myles', 23)")
+        (rollback
+          (do-query "INSERT INTO test (name, age) VALUES ('Myles', 23)")
+          (should= 2 (test-count)))
+        (should= 1 (test-count)))
+      (should= 0 (test-count)))
+
+           )
 
   (context "transaction"
     (it "commits"

sql/spec/hyperion/sql/key_spec.clj

@@ -11,7 +11,7 @@
     (should-not= (compose-key "foo" 1) (compose-key "bar" 1)))
 
   (it "can parse a key"
-    (let [key (compose-key :foo 123)]
+    (let [key (compose-key "foo" 123)]
       (should= ["foo" 123] (decompose-key key))))
 
   )

sql/src/hyperion/sql/jdbc.clj

@@ -1,5 +1,6 @@
 (ns hyperion.sql.jdbc
   (:use
+    [hyperion.key :only [generate-id]]
     [hyperion.sql.connection :only [connection]]
     [hyperion.sql.query :only [query-str params]]
     [hyperion.sql.query-builder]))
@@ -133,14 +134,45 @@
 (defmacro transaction [& body]
   `(transaction-fn (fn [] ~@body)))
 
+(def ^{:private true :dynamic true} *in-txn* false)
+
+(defn with-txn [f]
+  (if *in-txn*
+    (f)
+    (binding [*in-txn* true]
+      (without-auto-commit
+        (try
+          (let [result (f)]
+            (.commit (connection))
+            result)
+          (catch Exception e
+            (.rollback (connection))
+            (throw e)))))))
+
 (def ^{:private true :dynamic true} *in-rollback* false)
 
+(defn new-savepoint-id [] (generate-id))
+
+(defn exec [query]
+  (let [stmt (.createStatement (connection))]
+    (.executeUpdate stmt query)
+    (.close stmt)))
+
+(defn- begin-savepoint []
+  (let [savepoint-id (new-savepoint-id)]
+    (exec (str "SAVEPOINT \"" savepoint-id "\""))))
+
+(defn- rollback-to-savepoint [savepoint-id]
+  (exec (str "ROLLBACK TO SAVEPOINT \"" savepoint-id "\"")))
+
 (defn rollback-fn [f]
-  (without-auto-commit
-    (try
-      (f)
-      (finally
-        (.rollback (connection))))))
+  (with-txn
+    (fn []
+      (let [savepoint-id (begin-savepoint)]
+        (try
+          (f)
+          (finally
+            (rollback-to-savepoint savepoint-id)))))))
 
 (defmacro rollback [& body]
   `(rollback-fn (fn [] ~@body)))