Move SlimeUtils to vespajlib

2 files changed, 191 insertions, 0 deletions

diff --git a/vespajlib/src/main/java/com/yahoo/slime/SlimeUtils.java b/vespajlib/src/main/java/com/yahoo/slime/SlimeUtils.java
new file mode 100644
index 00000000000..4d0b3a8ff2e
--- /dev/null
+++ b/vespajlib/src/main/java/com/yahoo/slime/SlimeUtils.java
@@ -0,0 +1,110 @@
+// Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.slime;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.util.Optional;
+
+/**
+ * Extra utilities/operations on slime trees.
+ *
+ * @author Ulf Lilleengen
+ */
+public class SlimeUtils {
+
+    public static void copyObject(Inspector from, Cursor to) {
+        if (from.type() != Type.OBJECT) {
+            throw new IllegalArgumentException("Cannot copy object: " + from);
+        }
+        from.traverse((ObjectTraverser) (name, inspector) -> setObjectEntry(inspector, name, to));
+
+    }
+
+    private static void setObjectEntry(Inspector from, String name, Cursor to) {
+        switch (from.type()) {
+            case NIX:
+                to.setNix(name);
+                break;
+            case BOOL:
+                to.setBool(name, from.asBool());
+                break;
+            case LONG:
+                to.setLong(name, from.asLong());
+                break;
+            case DOUBLE:
+                to.setDouble(name, from.asDouble());
+                break;
+            case STRING:
+                to.setString(name, from.asString());
+                break;
+            case DATA:
+                to.setData(name, from.asData());
+                break;
+            case ARRAY:
+                Cursor array = to.setArray(name);
+                copyArray(from, array);
+                break;
+            case OBJECT:
+                Cursor object = to.setObject(name);
+                copyObject(from, object);
+                break;
+        }
+    }
+
+    private static void copyArray(Inspector from, final Cursor to) {
+        from.traverse((ArrayTraverser) (i, inspector) -> addValue(inspector, to));
+    }
+
+    private static void addValue(Inspector from, Cursor to) {
+        switch (from.type()) {
+            case NIX:
+                to.addNix();
+                break;
+            case BOOL:
+                to.addBool(from.asBool());
+                break;
+            case LONG:
+                to.addLong(from.asLong());
+                break;
+            case DOUBLE:
+                to.addDouble(from.asDouble());
+                break;
+            case STRING:
+                to.addString(from.asString());
+                break;
+            case DATA:
+                to.addData(from.asData());
+                break;
+            case ARRAY:
+                Cursor array = to.addArray();
+                copyArray(from, array);
+                break;
+            case OBJECT:
+                Cursor object = to.addObject();
+                copyObject(from, object);
+                break;
+        }
+
+    }
+
+    public static byte[] toJsonBytes(Slime slime) throws IOException {
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        new JsonFormat(true).encode(baos, slime);
+        return baos.toByteArray();
+    }
+
+    public static Slime jsonToSlime(byte[] json) {
+        Slime slime = new Slime();
+        new JsonDecoder().decode(slime, json);
+        return slime;
+    }
+
+    public static Slime jsonToSlime(String json) {
+        return jsonToSlime(json.getBytes(StandardCharsets.UTF_8));
+    }
+
+    public static Optional<String> optionalString(Inspector inspector) {
+        return Optional.of(inspector.asString()).filter(s -> !s.isEmpty());
+    }
+}
diff --git a/vespajlib/src/test/java/com/yahoo/slime/SlimeUtilsTest.java b/vespajlib/src/test/java/com/yahoo/slime/SlimeUtilsTest.java
new file mode 100644
index 00000000000..8b13ee74aed
--- /dev/null
+++ b/vespajlib/src/test/java/com/yahoo/slime/SlimeUtilsTest.java
@@ -0,0 +1,81 @@
+// Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.slime;
+
+import com.yahoo.text.Utf8;
+import org.junit.Test;
+
+import java.io.IOException;
+
+import static org.hamcrest.core.Is.is;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.assertTrue;
+
+/**
+ * @author Ulf Lilleengen
+ */
+public class SlimeUtilsTest {
+
+    @Test
+    public void test_copying_slime_types_into_cursor() {
+        Slime slime = new Slime();
+        Cursor root = slime.setObject();
+        root.setString("foo", "foobie");
+        Cursor subobj = root.setObject("bar");
+
+        Slime slime2 = new Slime();
+        Cursor root2 = slime2.setObject();
+        root2.setString("a", "a");
+        root2.setLong("b", 2);
+        root2.setBool("c", true);
+        root2.setDouble("d", 3.14);
+        root2.setData("e", new byte[]{0x64});
+        root2.setNix("f");
+
+        SlimeUtils.copyObject(slime2.get(), subobj);
+
+        assertThat(root.toString(), is("{\"foo\":\"foobie\",\"bar\":{\"a\":\"a\",\"b\":2,\"c\":true,\"d\":3.14,\"e\":\"0x64\",\"f\":null}}"));
+    }
+
+    @Test
+    public void test_copying_slime_arrays_into_cursor() {
+        Slime slime = new Slime();
+        Cursor root = slime.setObject();
+        root.setString("foo", "foobie");
+        Cursor subobj = root.setObject("bar");
+
+        Slime slime2 = new Slime();
+        Cursor root2 = slime2.setObject();
+        Cursor array = root2.setArray("a");
+        array.addString("foo");
+        array.addLong(4);
+        array.addBool(true);
+        array.addDouble(3.14);
+        array.addNix();
+        array.addData(new byte[]{0x64});
+        Cursor objinner = array.addObject();
+        objinner.setString("inner", "binner");
+
+        SlimeUtils.copyObject(slime2.get(), subobj);
+
+        assertThat(root.toString(), is("{\"foo\":\"foobie\",\"bar\":{\"a\":[\"foo\",4,true,3.14,null,\"0x64\",{\"inner\":\"binner\"}]}}"));
+    }
+
+    @Test
+    public void test_slime_to_json() throws IOException {
+        Slime slime = new Slime();
+        Cursor root = slime.setObject();
+        root.setString("foo", "foobie");
+        root.setObject("bar");
+        String json = Utf8.toString(SlimeUtils.toJsonBytes(slime));
+        assertThat(json, is("{\"foo\":\"foobie\",\"bar\":{}}"));
+    }
+
+    @Test
+    public void test_json_to_slime() {
+        byte[] json = Utf8.toBytes("{\"foo\":\"foobie\",\"bar\":{}}");
+        Slime slime = SlimeUtils.jsonToSlime(json);
+        assertThat(slime.get().field("foo").asString(), is("foobie"));
+        assertTrue(slime.get().field("bar").valid());
+    }
+
+}