Add :vars to options to allow variables to be specified (#32)

* Add :vars to options to allow variables to be specified (#31)
* Revise :vars to accept literal values, not JSON encoding of those values

Author: charles-dyfis-net

Diff for: src/jq/api/api_impl.clj

@@ -16,6 +16,11 @@
 
 (def jq-version Versions/JQ_1_6)
 
+(defn ->JsonNode ^JsonNode [data]
+  (if (instance? JsonNode data)
+    data
+    (.valueToTree mapper data)))
+
 (defn ->absolute-path
   "FileSystemModuleLoader requires absolute paths."
   ^Path [^String file-path]
@@ -50,16 +55,6 @@
     (.loadFunctions (BuiltinFunctionLoader/getInstance) jq-version scope)
     scope))
 
-(defn new-scope
-  (^Scope [] (Scope/newChildScope root-scope))
-  (^Scope [opts]
-   (let [^Scope scope (new-scope)
-         module-paths (get opts :modules)
-         module-paths (if (string? module-paths) [module-paths] module-paths)]
-     (when (seq module-paths)
-       (setup-modules! scope module-paths))
-     scope)))
-
 ; Helper interface that specifies a method to get a string value.
 (definterface IContainer
   ; net.thisptr.jackson.jq/Output
@@ -115,6 +110,20 @@
   ^String [^JsonNode data ^JsonQuery query ^Scope scope ^IContainer output-container]
   (json-node->string (apply-json-query-on-json-node data query scope output-container)))
 
+(defn new-scope
+  (^Scope [] (Scope/newChildScope root-scope))
+  (^Scope [opts]
+   (let [^Scope scope (new-scope)
+         module-paths (get opts :modules)
+         module-paths (if (string? module-paths) [module-paths] module-paths)
+         variables (get opts :vars)]
+     (when (seq module-paths)
+       (setup-modules! scope module-paths))
+     (when variables
+       (doseq [[key value] variables]
+        (.setValue scope (name key) (->JsonNode value))))
+     scope)))
+
 (defn compile-query
   "Compiles a JQ query string into a JsonQuery object."
   ^JsonQuery [^String query]

Diff for: test/jq/api_test.clj

@@ -9,6 +9,16 @@
 (def query "map(.+1)")
 (def result-string "[2,3,4]")
 
+(deftest variables
+  (testing "passing variables in at compile time"
+    (let [script "[$var1, $var2, $var3]"
+          processor-fn (jq/flexible-processor script {:output :string
+                                                      :vars {:var1 "hello"
+                                                             "var2" "world"
+                                                             :var3 123}})
+          resp (processor-fn "null")]
+      (is (= resp "[\"hello\",\"world\",123]")))))
+
 (deftest script-from-a-file
   (let [modules-dir "test/resources"
         script-file (str modules-dir "/scripts.jq")]