✨ feature: Python input transformer

pom.xml

@@ -95,6 +95,12 @@
             <version>22.0.0.2</version>
         </dependency>
 
+        <dependency>
+            <groupId>org.python</groupId>
+            <artifactId>jython-standalone</artifactId>
+            <version>2.7.2</version>
+        </dependency>
+
         <dependency>
             <groupId>org.junit.jupiter</groupId>
             <artifactId>junit-jupiter-api</artifactId>

src/main/java/gg/amy/utt/UTT.java

@@ -32,7 +32,8 @@ InputFormat.YAML, new YamlTransformer(),
             InputFormat.PLAIN, new PlainTransformer(),
             InputFormat.PROPERTIES, new PropertiesTransformer(),
             InputFormat.TOML, new TomlTransformer(),
-            InputFormat.BASE64, new Base64Transformer()
+            InputFormat.BASE64, new Base64Transformer(),
+            InputFormat.PYTHON, new PythonTransformer()
     );
     private static final Map<OutputFormat, Transformer> OUTPUT_TRANSFORMERS = Map.of(
             OutputFormat.CSV, new CsvTransformer(),

src/main/java/gg/amy/utt/data/InputFormat.java

@@ -13,4 +13,5 @@ public enum InputFormat {
     TOML,
     PLAIN,
     BASE64,
+    PYTHON,
 }

src/main/java/gg/amy/utt/transform/impl/PythonTransformer.java

@@ -0,0 +1,37 @@
+package gg.amy.utt.transform.impl;
+
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import gg.amy.utt.transform.TransformationContext;
+import gg.amy.utt.transform.Transformer;
+import org.python.util.PythonInterpreter;
+
+import javax.annotation.Nonnull;
+
+/**
+ * @author amy
+ * @since 3/11/22.
+ */
+public class PythonTransformer implements Transformer {
+    private static final ObjectMapper MAPPER = new ObjectMapper();
+
+    @Nonnull
+    @Override
+    public Object transformInput(@Nonnull final TransformationContext ctx, @Nonnull final String input) {
+        final var interpreter = new PythonInterpreter();
+        interpreter.set("input", input);
+        interpreter.exec("import ast, json; output = json.dumps(ast.literal_eval(input))");
+        final var output = interpreter.get("output");
+        try {
+            return MAPPER.readValue(output.asString(), Object.class);
+        } catch(@Nonnull final JsonProcessingException e) {
+            throw new IllegalStateException(e);
+        }
+    }
+
+    @Nonnull
+    @Override
+    public String transformOutput(@Nonnull final TransformationContext ctx, @Nonnull final Object input) {
+        throw new UnsupportedOperationException("Python objects are not a valid output format!");
+    }
+}

src/test/java/gg/amy/utt/transform/impl/PythonTransformerTest.java

@@ -0,0 +1,24 @@
+package gg.amy.utt.transform.impl;
+
+import gg.amy.utt.data.InputFormat;
+import gg.amy.utt.data.OutputFormat;
+import gg.amy.utt.transform.TransformationContext;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+/**
+ * @author amy
+ * @since 3/11/22.
+ */
+public class PythonTransformerTest {
+    @Test
+    public void testPythonToJsonTransformation() {
+        final var input = """
+                {'key': 'value', 'list': [1, 2, 3]}
+                """;
+        final var ctx = new TransformationContext(InputFormat.PYTHON, OutputFormat.JSON, null, null, false, false);
+        final var out = new JsonTransformer().transformOutput(ctx, new PythonTransformer().transformInput(ctx, input));
+        assertEquals("{\"list\":[1,2,3],\"key\":\"value\"}", out);
+    }
+}