make clause-building extensible, move helper fns to honeysql.helpers

src/honeysql/core.clj

@@ -2,6 +2,7 @@
   (:refer-clojure :exclude [group-by format])
   (:require [honeysql.format :as format]
             [honeysql.types :as types]
+            [honeysql.helpers :refer [build-clause]]
             [honeysql.util :refer [defalias]]))
 
 (defalias call types/call)
@@ -9,157 +10,12 @@
 (defalias format format/format)
 (defalias format-predicate format/format-predicate)
 
-(defn select [& fields]
+(defn build [& clauses]
-  (let [[m fields] (if (map? (first fields))
-                     [(first fields) (rest fields)]
-                     [{} fields])]
-    (assoc m :select fields)))
-
-(defn merge-select [sql-map & fields]
-  (update-in sql-map [:select] concat fields))
-
-(defn un-select [sql-map & fields]
-  (update-in sql-map [:select] #(remove (set fields) %)))
-
-(defn from [& tables]
-  (let [[m tables] (if (map? (first tables))
-                     [(first tables) (rest tables)]
-                     [{} tables])]
-    (assoc m :from tables)))
-
-(defn merge-from [sql-map & tables]
-  (update-in sql-map [:from] concat tables))
-
-(defn where [& preds]
-  (let [[m preds] (if (map? (first preds))
-                    [(first preds) (rest preds)]
-                    [{} preds])]
-    (assoc m :where (if (= 1 (count preds))
-                      (first preds)
-                      (vec (cons :and preds))))))
-
-(defn merge-where [sql-map & preds]
-  (if (empty? preds)
-    sql-map
-    (let [[merge-op preds] (if (keyword? (first preds))
-                             [(first preds) (rest preds)]
-                             [:and preds])]
-      (assoc sql-map :where (if (contains? sql-map :where)
-                              (vec (concat [merge-op (:where sql-map)] preds))
-                              (vec (if (= 1 (count preds))
-                                     (first preds)
-                                     (cons merge-op preds))))))))
-
-(defn join [& clauses]
-  (let [[m clauses] (if (map? (first clauses))
-                      [(first clauses) (rest clauses)]
-                      [{} clauses])]
-    (assoc m :join clauses)))
-
-(defn merge-join [sql-map & clauses]
-  (update-in sql-map [:join] concat clauses))
-
-(defn group-by [& fields]
-  (let [[m fields] (if (map? (first fields))
-                     [(first fields) (rest fields)]
-                     [{} fields])]
-    (assoc m :group-by fields)))
-
-(defn merge-group-by [sql-map & fields]
-  (update-in sql-map [:group-by] concat fields))
-
-(defn having [& preds]
-  (let [[m preds] (if (map? (first preds))
-                    [(first preds) (rest preds)]
-                    [{} preds])]
-    (assoc m :having (if (= 1 (count preds))
-                       (first preds)
-                       (vec (cons :and preds))))))
-
-(defn merge-having [sql-map & preds]
-  (if (empty? preds)
-    sql-map
-    (let [[merge-op preds] (if (keyword? (first preds))
-                             [(first preds) (rest preds)]
-                             [:and preds])]
-      (assoc sql-map :having (if (contains? sql-map :having)
-                               (vec (concat [merge-op (:having sql-map)] preds))
-                               (vec (if (= 1 (count preds))
-                                      (first preds)
-                                      (cons merge-op preds))))))))
-
-(defn order-by [& fields]
-  (let [[m fields] (if (map? (first fields))
-                     [(first fields) (rest fields)]
-                     [{} fields])]
-    (assoc m :order-by fields)))
-
-(defn merge-order-by [sql-map & fields]
-  (update-in sql-map [:order-by] concat fields))
-
-(defn limit
-  ([l]
-     (limit {} l))
-  ([sql-map l]
-     (assoc sql-map :limit l)))
-
-(defn offset
-  ([o]
-     (offset {} o))
-  ([sql-map o]
-     (assoc sql-map :offset o)))
-
-(defn modifiers [& ms]
-  (let [[m ms] (if (map? (first ms))
-                 [(first ms) (rest ms)]
-                 [{} ms])]
-    (assoc m :modifiers ms)))
-
-(defn merge-modifiers [sql-map & ms]
-  (update-in sql-map [:modifiers] concat ms))
-
-(def ^:private handlers
-  {:select select
-   :from from
-   :where where
-   :join join
-   :group-by group-by
-   :having having
-   :order-by order-by
-   :limit limit
-   :offset offset
-   :modifiers modifiers})
-
-(def ^:private merge-handlers
-  {:select merge-select
-   :from merge-from
-   :where merge-where
-   :join merge-join
-   :group-by merge-group-by
-   :having merge-having
-   :order-by merge-order-by
-   :limit limit
-   :offset offset
-   :modifiers merge-modifiers})
-
-(defn- build-sql [handlers clauses]
   (let [[base clauses] (if (map? (first clauses))
                          [(first clauses) (rest clauses)]
                          [{} clauses])]
     (reduce
      (fn [sql-map [op args]]
-       (if-let [handler (handlers op)]
+       (build-clause op sql-map args))
-         (if (or (#{:where :having} op) (not (coll? args)))
-           (if (nil? args)
-             sql-map
-             (handler sql-map args))
-           (apply handler sql-map args))
-         sql-map))
      base
      (partition 2 clauses))))
-
-(defn sql [& clauses]
-  (build-sql handlers clauses))
-
-(defn merge-sql [& clauses]
-  (build-sql merge-handlers clauses))

src/honeysql/helpers.clj

@@ -0,0 +1,136 @@
+(ns honeysql.helpers)
+
+(defmulti build-clause (fn [name & args]
+                         name))
+
+(defmethod build-clause :default [_ m & args]
+  m)
+
+(defmacro defhelper [helper arglist & more]
+  (let [kw (keyword (name helper))]
+    `(do
+       (defmethod build-clause ~kw ~(into ['_] arglist) ~@more)
+       (defn ~helper [& args#]
+         (let [[m# args#] (if (map? (first args#))
+                            [(first args#) (rest args#)]
+                            [{} args#])]
+           (build-clause ~kw m# args#))))))
+
+(defn collify [x]
+  (if (coll? x) x [x]))
+
+(defhelper select [m fields]
+  (assoc m :select (collify fields)))
+
+(defhelper merge-select [m fields]
+  (update-in m [:select] concat (collify fields)))
+
+(defhelper un-select [m fields]
+  (update-in m [:select] #(remove (set (collify fields)) %)))
+
+(defhelper from [m tables]
+  (assoc m :from (collify tables)))
+
+(defhelper merge-from [m tables]
+  (update-in m [:from] concat (collify tables)))
+
+(defmethod build-clause :where [_ m pred]
+  (if (nil? pred)
+    m
+    (assoc m :where pred)))
+
+(defn- prep-where [args]
+  (let [[m preds] (if (map? (first args))
+                    [(first args) (rest args)]
+                    [{} args])
+        [logic-op preds] (if (keyword? (first preds))
+                           [(first preds) (rest preds)]
+                           [:and preds])
+        pred (if (= 1 (count preds))
+               (first preds)
+               (into [logic-op] preds))]
+    [m pred logic-op]))
+
+(defn where [& args]
+  (let [[m pred] (prep-where args)]
+    (if (nil? pred)
+      m
+      (assoc m :where pred))))
+
+(defmethod build-clause :merge-where [_ m pred]
+  (if (nil? pred)
+    m
+    (assoc m :where (if (not (nil? (:where m)))
+                      [:and (:where m) pred]
+                      pred))))
+
+(defn merge-where [& args]
+  (let [[m pred logic-op] (prep-where args)]
+    (if (nil? pred)
+      m
+      (assoc m :where (if (not (nil? (:where m)))
+                        [logic-op (:where m) pred]
+                        pred)))))
+
+(defhelper join [m clauses]
+  (assoc m :join clauses))
+
+(defhelper merge-join [m clauses]
+  (update-in m [:join] concat clauses))
+
+(defmethod build-clause :group-by [_ m fields]
+  (assoc m :group-by (collify fields)))
+
+(defn group [& args]
+  (let [[m fields] (if (map? (first args))
+                     [(first args) (rest args)]
+                     [{} args])]
+    (build-clause :group-by m fields)))
+
+(defhelper merge-group-by [m fields]
+  (update-in m [:group-by] concat (collify fields)))
+
+(defmethod build-clause :having [_ m pred]
+  (if (nil? pred)
+    m
+    (assoc m :having pred)))
+
+(defn having [& args]
+  (let [[m pred] (prep-where args)]
+    (if (nil? pred)
+      m
+      (assoc m :having pred))))
+
+(defmethod build-clause :merge-having [_ m pred]
+  (if (nil? pred)
+    m
+    (assoc m :having (if (not (nil? (:having m)))
+                       [:and (:having m) pred]
+                       pred))))
+
+(defn merge-having [& args]
+  (let [[m pred logic-op] (prep-where args)]
+    (if (nil? pred)
+      m
+      (assoc m :having (if (not (nil? (:having m)))
+                         [logic-op (:having m) pred]
+                         pred)))))
+
+(defhelper order-by [m fields]
+  (assoc m :order-by (collify fields)))
+
+(defhelper merge-order-by [m fields]
+  (update-in m [:order-by] concat (collify fields)))
+
+(defhelper limit [m l]
+  (assoc m :limit (if (coll? l) (first l) l)))
+
+(defhelper offset [m o]
+  (assoc m :offset (if (coll? o) (first o) o)))
+
+(defhelper modifiers [m ms]
+  (assoc m :modifiers (collify ms)))
+
+(defhelper merge-modifiers [m ms]
+  (update-in m [:modifiers] concat (collify ms)))
+

test/honeysql/core_test.clj

@@ -1,28 +1,32 @@
 (ns honeysql.core-test
-  (:refer-clojure :exclude [format group-by])
+  (:refer-clojure :exclude [format])
   (:require [clojure.test :refer [deftest testing is]]
-            [honeysql.core :refer :all]))
+            [honeysql.core :refer :all]
+            [honeysql.helpers :refer :all]))
 
 ;; TODO: more tests
 
 (deftest test-select
-  (let [sqlmap (-> (select :f.* :b.baz :c.quux (call :now) (raw "@x := 10"))
+  (let [m1 (-> (select :f.* :b.baz :c.quux [:b.bla "bla-bla"]
-                   (modifiers :distinct)
+                       (call :now) (raw "@x := 10"))
-                   (from [:foo :f] [:baz :b])
+               (un-select :c.quux)
-                   (join [[:clod :c] [:= :f.a :c.d] :left]
+               (modifiers :distinct)
-                         [:draq [:= :f.b :draq.x]])
+               (from [:foo :f] [:baz :b])
-                   (where [:or
+               (join [[:clod :c] [:= :f.a :c.d] :left]
-                           [:and [:= :f.a "bort"] [:not= :b.baz "gabba"]]
+                     [:draq [:= :f.b :draq.x]])
-                           [:in :f.e [1 2 3]]
+               (where [:or
-                           [:between :f.e 10 20]])
+                       [:and [:= :f.a "bort"] [:not= :b.baz "gabba"]]
-                   (group-by :f.a)
+                       [:< 1 2 3]
-                   (having [:< 0 :f.e])
+                       [:in :f.e [1 2 3]]
-                   (order-by [:b.baz :desc] :c.quux)
+                       [:between :f.e 10 20]])
-                   (limit 50)
+               (merge-where [:not= nil :b.bla])
-                   (offset 10))]
+               (group :f.a)
-    (testing "sqlmap formats correctly"
+               (having [:< 0 :f.e])
-      (is (= (format sqlmap)
+               (order-by [:b.baz :desc] :c.quux)
-             ["SELECT DISTINCT f.*, b.baz, c.quux, NOW(), @x := 10 FROM foo AS f, baz AS b LEFT JOIN clod AS c ON (f.a = c.d) JOIN draq ON (f.b = draq.x) WHERE (((f.a = ?) AND (b.baz != ?)) OR (f.e IN (1, 2, 3)) OR f.e BETWEEN 10 AND 20) GROUP BY f.a HAVING (0 < f.e) ORDER BY b.baz DESC, c.quux LIMIT 50 OFFSET 10"
+               (limit 50)
-              "bort" "gabba"])))
+               (offset 10))]
-    (testing "sqlmap prints and reads correctly"
+    (testing "SQL data formats correctly"
-      (is (= sqlmap (read-string (pr-str sqlmap)))))))
+      (is (= (format m1)
+             ["SELECT DISTINCT f.*, b.baz, b.bla AS \"bla-bla\", NOW(), @x := 10 FROM foo AS f, baz AS b LEFT JOIN clod AS c ON f.a = c.d JOIN draq ON f.b = draq.x WHERE (((f.a = ? AND b.baz <> ?) OR (1 < 2 AND 2 < 3) OR (f.e IN (1, 2, 3)) OR f.e BETWEEN 10 AND 20) AND b.bla IS NOT NULL) GROUP BY f.a HAVING 0 < f.e ORDER BY b.baz DESC, c.quux LIMIT 50 OFFSET 10" "bort" "gabba"])))
+    (testing "SQL data prints and reads correctly"
+      (is (= m1 (read-string (pr-str m1)))))))