feat: get_policies: Way to obtain policy files and content (#267)

closes #254

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>

bindings/java/src/lib.rs

@@ -89,6 +89,25 @@ pub extern "system" fn Java_com_microsoft_regorus_Engine_nativeGetPackages(
     }
 }
 
+#[no_mangle]
+pub extern "system" fn Java_com_microsoft_regorus_Engine_nativeGetPolicies(
+    env: JNIEnv,
+    _class: JClass,
+    engine_ptr: jlong,
+) -> jstring {
+    let res = throw_err(env, |env| {
+        let engine = unsafe { &mut *(engine_ptr as *mut Engine) };
+        let policies = engine.get_policies_as_json()?;
+        let policies_json = env.new_string(&policies)?;
+        Ok(policies_json.into_raw())
+    });
+
+    match res {
+        Ok(val) => val,
+        Err(_) => JObject::null().into_raw(),
+    }
+}
+
 #[no_mangle]
 pub extern "system" fn Java_com_microsoft_regorus_Engine_nativeClearData(
     env: JNIEnv,

bindings/java/src/main/java/com/microsoft/regorus/Engine.java

@@ -26,6 +26,7 @@ public class Engine implements AutoCloseable, Cloneable {
     private static native String nativeAddPolicy(long enginePtr, String path, String rego);
     private static native String nativeAddPolicyFromFile(long enginePtr, String path);
     private static native String nativeGetPackages(long enginePtr);
+    private static native String nativeGetPolicies(long enginePtr);
     private static native void nativeClearData(long enginePtr);
     private static native void nativeAddDataJson(long enginePtr, String data);
     private static native void nativeAddDataJsonFromFile(long enginePtr, String path);
@@ -96,6 +97,15 @@ public class Engine implements AutoCloseable, Cloneable {
         return nativeGetPackages(enginePtr);
     }
     
+    /**
+     * Get list of loaded policies.
+     * 
+     * @return List of Rego policies as a JSON array of sources.
+     */
+    public String getPolicies() {
+        return nativeGetPolicies(enginePtr);
+    }
+    
     /**
      * Clears the data  document.
      */