diff options
Diffstat (limited to 'src')
-rw-r--r-- | src/clojure_sql/compiler.clj | 216 | ||||
-rw-r--r-- | src/clojure_sql/core.clj | 87 | ||||
-rw-r--r-- | src/clojure_sql/dsl.clj | 49 | ||||
-rw-r--r-- | src/clojure_sql/query.clj | 19 | ||||
-rw-r--r-- | src/clojure_sql/util.clj | 3 | ||||
-rw-r--r-- | src/clojure_sql/writer.clj | 69 |
6 files changed, 273 insertions, 170 deletions
diff --git a/src/clojure_sql/compiler.clj b/src/clojure_sql/compiler.clj index ca8d2d9..7ded112 100644 --- a/src/clojure_sql/compiler.clj +++ b/src/clojure_sql/compiler.clj @@ -1,7 +1,9 @@ (ns clojure-sql.compiler - (:require [clojure.string :as string])) - - + (:refer-clojure :exclude [compile sequence]) + (:require [clojure.string :as string] + [clojure-sql.query :refer [query?]] + [clojure-sql.util :as u] + [clojure-sql.writer :as w :refer [return lift p-lift sequence do-m tell >>]])) (defn add-parentheses [s] (str \( s \))) @@ -26,121 +28,129 @@ +;; we use the $ prefix to denote a lifted function +(def $add-parentheses (lift add-parentheses)) +(def $str (lift str)) + + + ;; ============================================================== ;; Utility functions for the compile-* functions ;; ============================================================== -;; compile-* multimethods are of the signature: -;; (db, expr) -> [SQL & replacements] - -(def is-unary? (comp boolean '#{"not"} name)) -(def is-binary? (comp boolean '#{"=" "<" ">" "<=" ">=" "is" "in" "+" "-" "/" "*"} name)) -(def is-operator? (comp boolean '#{"and" "or"} name)) -(defn c-return [val] [val]) -(defn c-lift [f & orig-args] - (fn [& c-args] - (apply vector - (apply f (concat orig-args - (map first c-args))) - (apply concat (map rest c-args))))) -(def c-str (c-lift str)) -(def c-join (fn [sep args] - (apply vector - (string/join sep (map first args)) - (apply concat (map rest args))))) -(def c-add-parentheses (c-lift add-parentheses)) +(def ^:private named? (some-fn string? symbol? keyword?)) +(def quote? (comp boolean '#{"quote"} name)) +(def unary? (comp boolean '#{"not" "exists"} name)) +(def binary? (comp boolean '#{"=" "<" ">" "<=" ">=" "is" "in"} name)) +(def operator? (comp boolean '#{"and" "or" "+" "-" "/" "*"} name)) ;; ============================================================== ;; compile-* functions (turning a map into a query string) ;; ============================================================== +;; compile-* multimethods are of the signature: +;; (db, expr) -> (fn [s] [sql]) + +(declare compile-query compile-expression) + +(defmulti compile-expression-sequential (fn [db ex])) +(defmethod compile-expression-sequential :default [db ex] + (let [compile-exprs #(map (partial compile-expression db) %) + op (name (first ex)) + num-args (dec (count ex))] + (-> (condp u/funcall (first ex) + quote? (do (assert (= num-args 1) "`quote` must only take one argument") + (>> (tell (second ex)) (return "?"))) + unary? (do (assert (= num-args 1) (str "Unary operator `" op "` must take one argument")) + (do-m :let [exprs (compile-exprs ex)] + vals <- (apply sequence exprs) + (return (string/join "" vals)))) + binary? (do (assert (= num-args 2) (str "Binary operator `" op "` must take two arguments")) + (do-m :let [[op left right] (compile-exprs ex)] + vals <- (sequence left op right) + (return (string/join " " vals)))) + operator? (do-m :let [[op & exprs] (compile-exprs ex)] + vals <- (apply sequence (interpose op exprs)) + (return (string/join " " vals))) + (do-m :let [fn-name (function-name db (first ex)) + exprs (compile-exprs (rest ex))] + vals <- (apply sequence exprs) + (return (str fn-name + (add-parentheses (string/join "," vals)))))) + $add-parentheses))) + (defmulti compile-expression (fn [db _] db)) (defmethod compile-expression :default [db ex] - (condp #(%1 %2) ex - nil? (c-return "NULL") - vector? (c-return (str (table-name db (first ex)) \. (field-name db (second ex)))) - keyword? (c-return (field-name db ex)) - string? ["?" ex] ;;(sql-string db ex) - symbol? (c-return (string/upper-case (name ex))) - sequential? (-> (condp #(%1 %2) (first ex) - is-unary? (if (= (count ex) 2) - (->> ex - (map (partial compile-expression db)) - (c-join " ")) - (throw (ex-info "Unary operators can only take one argument." - {:operator (first ex) - :arguments (rest ex)}))) - is-binary? (if (= (count ex) 3) - (->> (rest ex) - (map (partial compile-expression db)) - (interpose (compile-expression db (first ex))) - (c-join " ")) - (throw (ex-info "Binary operators must take two arguments." - {:operator (first ex) - :arguments (rest ex)}))) - is-operator? (->> (rest ex) - (map (partial compile-expression db)) - (interpose (compile-expression db (first ex))) - (c-join " ")) - (->> (rest ex) - (map (partial compile-expression db)) - (c-join ", ") - c-add-parentheses - (c-str (c-return (function-name db (first ex)))))) - c-add-parentheses) - (c-return ex))) + (condp u/funcall ex + query? ($add-parentheses (compile-query db ex)) + nil? (return "NULL") + vector? (return (str (table-name db (first ex)) \. (field-name db (second ex)))) + keyword? (return (field-name db ex)) + string? (>> (tell ex) (return "?")) ;;(sql-string db ex) + symbol? (return (string/upper-case (name ex))) + sequential? (compile-expression-sequential db ex) + (return ex))) (defn ^:private make-table-name [db table & [alias]] (if (or (= table alias) (nil? alias)) - (table-name db table) - (str (table-name db table) " AS " (field-name db alias))) ) - -(defn ^:private make-field-name [db table field & [alias]] - (if (or (= field alias) (nil? alias)) - (str (table-name db table) \. (field-name db field)) - (str (table-name db table) \. (field-name db field) " AS " (field-name db alias)))) + (return (table-name db table)) + ($str (condp #(%1 %2) table + query? ($add-parentheses (compile-query db table)) + named? (return (table-name db table)) + (compile-expression db table)) + (return " AS ") + (return (table-name db alias))))) + +(defn ^:private make-field-name [db field & [alias]] + (if (and (vector? field) (or (= field alias) (nil? alias))) + (compile-expression db field) + ($str (compile-expression db field) + (return " AS ") + (return (field-name db alias))))) (defmulti compile-fields (fn [db _] db)) (defmethod compile-fields :default [db fields-map] (if (seq fields-map) - (->> (for [[[table field] alias] fields-map] - (make-field-name db table field alias)) - (string/join ", ") - c-return) - (c-return "*"))) + (->> (for [[field alias] fields-map] + (make-field-name db field alias)) + (apply sequence) + ((p-lift string/join ", "))) + (return "*"))) (defmulti compile-tables (fn [db _] db)) (defmethod compile-tables :default [db tables-map] (->> (for [[table alias] tables-map] (make-table-name db table alias)) - (string/join ", ") - c-return)) + (apply sequence) + ((p-lift string/join ", ")))) (defmulti compile-join (fn [db _] db)) (defmethod compile-join :default [db [type table-map on]] - (c-str (c-return (case type - :left " LEFT OUTER" - :right " RIGHT OUTER" - " INNER")) - (c-return " JOIN ") - (compile-tables db table-map) - (c-return " ON ") - (compile-expression db on))) + ($str (return (case type + :left " LEFT OUTER" + :right " RIGHT OUTER" + " INNER")) + (return " JOIN ") + (compile-tables db table-map) + (return " ON ") + (compile-expression db on))) (defmulti compile-joins (fn [db _] db)) (defmethod compile-joins :default [db joins] (->> joins (map (partial compile-join db)) - (c-join ""))) + (apply sequence) + ((p-lift string/join "")))) (defmulti compile-where (fn [db _] db)) (defmethod compile-where :default [db expr] (if expr - (c-str (c-return " WHERE ") (compile-expression db expr)))) + ($str (return " WHERE ") (compile-expression db expr)) + (return nil))) (defmulti compile-sort-by (fn [db _] db)) (defmethod compile-sort-by :default [db fields] @@ -148,22 +158,29 @@ (->> (for [[[table field] dir] fields] (str (make-field-name db table field) \space (string/upper-case (name dir)))) (string/join ",") - (apply str " ORDER BY ") - c-return))) + (apply $str (return " ORDER BY ")) + return) + (return nil))) (defmulti compile-query (fn [db _] db)) (defmethod compile-query :default [db {:keys [table fields joins where sort-by]}] - (c-str (c-return "SELECT ") - (compile-fields db fields) - (if table - (c-return " FROM ")) - (compile-tables db table) - (compile-joins db joins) - (compile-where db where) - (compile-sort-by db sort-by))) + ($str (return "SELECT ") + (compile-fields db fields) + (if table + (return " FROM ")) + (compile-tables db table) + (compile-joins db joins) + (compile-where db where) + (compile-sort-by db sort-by))) + +(defn compile [db query] + (let [[sql vars] ((compile-query db query) [])] + (vec (cons sql vars)))) + + ;; ============================================================== ;; A few DB specific overrides ;; ============================================================== @@ -184,4 +201,25 @@ (str \` (name table) \`)) +;;(compile nil {:table {:u :u}, :fields {[:v :x] :w}}) + + + + +;; Utility functions + +(defn insert! [db query & records] + {:pre [(empty? (:joins query))]} + ;; some code here + ($str (return "Carlo")) + ) + +(defn update! [db query & partial-records] + {:pre [(empty? (:joins query))]} + ;; some code here + ) +(defn delete! [db query] + {:pre [(empty? (:joins query))]} + ;; some code here + ) diff --git a/src/clojure_sql/core.clj b/src/clojure_sql/core.clj index cdfa1c9..4f88a53 100644 --- a/src/clojure_sql/core.clj +++ b/src/clojure_sql/core.clj @@ -3,58 +3,72 @@ (:require [clojure.set :as set] [clojure-sql.compiler :as c] [clojure-sql.dsl :as d] + [clojure-sql.query :as q] [clojure-sql.util :as u] [clojure.walk])) -(def table d/table) -(def project d/project) -(def rename d/rename) -(def join d/join) -(def select d/select) -(def sort-by d/sort-by) +(def ^:private ^:dynamic *database-type* nil) +(defn set-database-type! [new-type] + (alter-var-root #'*database-type* (constantly new-type)) + nil) + +(q/set-query-deref-behaviour! #(c/compile *database-type* %)) +(defmethod print-method clojure_sql.query.Query [query writer] + (binding [*out* writer] + (pr (c/compile nil query)))) + +(def table #'d/table) +(def project #'d/project) +(def rename #'d/rename) +(def join #'d/join) +(def select #'d/select) +(def sort-by #'d/sort-by) + +(def insert! #'c/insert!) +(def update! #'c/update!) +(def delete! #'c/delete!) + + -(def insert! d/insert!) -(def update! d/update!) -(def delete! d/delete!) (comment - (binding [*database-type* :mysql] - (let [users (-> (table :users) - (project [:id :username :password]) - (select '(= :deleted false))) - people (-> (table :people) - (project [:id :fname :sname]) - (select '(= :deleted false))) - uid-pid-match '(= :uid :pid) - is-carlo `(= :fname "Carlo'; SELECT * FROM users --")] - (-> (join (-> users - (rename {:id :uid})) - (join (-> people - (rename {:id :pid})) - (-> (table {:others :o}) - (project {:id :oid})) - :on '(= :pid :oid)) - :on uid-pid-match) - (select is-carlo) - (project [:fname :sname :oid])))) + (let [users (-> (table :users) + (project [:id :username :password]) + (select '(= :deleted false))) + people (-> (table :people) + (project [:id :fname :sname]) + (select '(= :deleted false))) + uid-pid-match '(= :uid :pid) + is-carlo `(= :fname "Carlo'; SELECT * FROM users --")] + (-> (join (-> users + (rename {:id :uid})) + (join (-> people + (rename {:id :pid})) + (-> (table {:others :o}) + (project {:id :oid})) + :on '(= :pid :oid)) + :on uid-pid-match) + (select is-carlo) + (project [:fname :sname :oid]))) (-> (table :users) - (join (table :something-else-with-a-username) - :on true) + (project [:username]) + (join (table :something-else-with-a-username)) (select '(or (= :username "john") (not (= :username "carlo")))) (project [:username])) (-> (table {:nodes :child}) (project [:parent-id, :name]) - (rename {:name :child.name}) + (rename {:name :child.name + :parent-id :pid}) (join (-> (table {:nodes :parent}) (project [:id, :name]) (rename {:name :parent.name})) - :on '(= :parent-id :id)) + :on '(= :pid :id)) (project [:child.name :parent.name])) (-> (table :users) @@ -67,12 +81,19 @@ :name :id})) (-> (table :users) (project {:id :name - :name :id})) + :name :id}) + (select '(= :id 10))) (-> (table :anotherStack) (project [:anotherNumber]) (join (-> (table :collection) (project [:number])))) + (-> (table :anotherStack) + (project [:anotherNumber]) + (join (-> (table :collection) + (project [:number]))) + (select '(is-okay 10))) + (-> (table :users) (select '(= (left :username 1) "bloo")))) diff --git a/src/clojure_sql/dsl.clj b/src/clojure_sql/dsl.clj index 006e637..996b55c 100644 --- a/src/clojure_sql/dsl.clj +++ b/src/clojure_sql/dsl.clj @@ -37,17 +37,24 @@ {:field field :query query}))) +(defn ^:private resolve-field [table aliases field] + (let [field-alias-lookup (u/flip-map aliases)] + (or (field-alias-lookup field) + (if table + [table field] + (ambiguous-error field))))) + +(defn ^:private resolve-fields [table aliases expression] + (cond (list? expression) (map (partial table aliases) expression) + (vector? expression) (mapv (partial table aliases) expression) + (keyword? expression) (resolve-field table aliases expression) + :else expression)) + (defn project [query fields] (let [table (if-not (:joins query) (-> query :table first val)) alias-lookup (u/flip-map (:fields query)) - original-name (fn [field] - (if (vector? field) - field - (or (get alias-lookup field nil) - (if table - [table field] - (ambiguous-error field query)))))] + original-name #(resolve-fields table (:fields query) %)] (assoc query :fields (->> (for [[key val] (if (map? fields) fields @@ -77,20 +84,6 @@ [(original-name key) val]) (into %))))) -(defn ^:private resolve-field [table aliases field] - (let [field-alias-lookup (u/flip-map aliases)] - (or (field-alias-lookup field) - (if table - [table field] - (ambiguous-error field))))) - -(defn ^:private resolve-fields [table aliases expression] - (clojure.walk/postwalk (fn [expr] - (cond - (keyword? expr) (resolve-field table aliases expr) - :else expr)) - expression)) - (defn ^:private combine-wheres [& wheres] (reduce (fn [acc where] (cond (nil? acc) where @@ -153,17 +146,3 @@ (if (vector? field) (resolve-field table-name (:fields query) field) [(resolve-field table-name (:fields query) field) :asc]))))) - - -(defn insert! [query & records] - {:pre [(empty? (:joins query))]} - ;; some code here - ) - -(defn update! [query & partial-records] - ;; some code here - ) - -(defn delete! [query] - ;; some code here - ) diff --git a/src/clojure_sql/query.clj b/src/clojure_sql/query.clj index 239aab4..00eb212 100644 --- a/src/clojure_sql/query.clj +++ b/src/clojure_sql/query.clj @@ -1,20 +1,13 @@ -(ns clojure-sql.query - (:require [clojure-sql.compiler :as c])) +(ns clojure-sql.query) - -(def ^:private ^:dynamic *database-type* nil) -(defn set-database-type! [new-type] - (alter-var-root #'*database-type* (constantly new-type)) - nil) - -(def ^:private ^:dynamic *query-deref-behaviour* #(c/compile-query *database-type* %)) +(def ^:private ^:dynamic *query-deref-behaviour* identity) (defn set-query-deref-behaviour! [f] (alter-var-root #'*query-deref-behaviour* (constantly f)) nil) -(defrecord ^:private Query [] +(defrecord ^:private Query [] clojure.lang.IDeref (deref [this] (*query-deref-behaviour* this))) -(defmethod print-method Query [query writer] - (binding [*out* writer] - (pr (c/compile-query nil query)))) + +(def query? (partial instance? (class (->Query)))) + diff --git a/src/clojure_sql/util.clj b/src/clojure_sql/util.clj index 03c90f1..cd8e8b6 100644 --- a/src/clojure_sql/util.clj +++ b/src/clojure_sql/util.clj @@ -1,5 +1,8 @@ (ns clojure-sql.util) +(defn funcall [f & args] + (apply f args)) + (defn flip [f] (fn [& args] (apply f (reverse args)))) diff --git a/src/clojure_sql/writer.clj b/src/clojure_sql/writer.clj new file mode 100644 index 0000000..5f4250b --- /dev/null +++ b/src/clojure_sql/writer.clj @@ -0,0 +1,69 @@ +(ns clojure-sql.writer + (:refer-clojure :exclude [sequence])) + + +;; A small writer monad implementation, for what we need +(defn return [x] + (fn [s] [x s])) + +(defn bind [mv f] + {:pre [(not (nil? mv))]} + (fn [s] + (let [[x s2] (mv s)] + ((f x) s2)))) + +(defn tell [val] + (fn [s] [nil (conj s val)])) + +(defn join [mv] + (bind mv identity)) + +(defn sequence + ([] (return nil)) + ([mv & mvs] + {:pre [(not (nil? mv))]} + (bind mv + (fn [x] + (bind (apply sequence mvs) + (fn [xs] + (return (cons x xs)))))))) + +(defn lift [f] + (fn [& args] + (bind (apply sequence args) + (fn [s] + (return (apply f s)))))) + +(defn p-lift [f & args] + (lift (apply partial f args))) + +(defn >> + ([arg] + arg) + ([arg1 & args] + (bind arg1 + (fn [x] + (apply >> args))))) + +(defn do-m* + ([] (throw (ex-info "No." {}))) + ([& args] + (or (if (nil? (next args)) + (first args)) + (if (= (first args) :let) + `(let ~(second args) + ~(apply do-m* (nnext args)))) + (if (= (name (second args)) "<-") + (let [[var <- val & others] args] + `(bind ~val + (fn [~var] + ~(apply do-m* others))))) + `(bind ~(first args) + (fn [_#] + ~(apply do-m* (next args))))))) + +(defmacro do-m [& args] + (apply do-m* args)) + +(defmacro do [& args] + (apply do-m* args)) |