[PAN-2946] refactor normalizeKeys method (#1826)

Move the `normalizeKeys` method into JsonUtil as Retesteth will re-use it.


Signed-off-by: Adrian Sutton <adrian.sutton@consensys.net>

config/src/main/java/tech/pegasys/pantheon/config/GenesisConfigFile.java

@@ -13,13 +13,12 @@
 package tech.pegasys.pantheon.config;
 
 import static java.nio.charset.StandardCharsets.UTF_8;
+import static tech.pegasys.pantheon.config.JsonUtil.normalizeKeys;
 
 import java.io.IOException;
-import java.util.Locale;
 import java.util.Optional;
 import java.util.stream.Stream;
 
-import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.node.ObjectNode;
 import com.google.common.collect.Streams;
 import com.google.common.io.Resources;
@@ -133,25 +132,4 @@ public class GenesisConfigFile {
               + "'");
     }
   }
-
-  /* Converts all to lowercase for easier lookup since the keys in a 'genesis.json' file are assumed
-   * case insensitive.
-   */
-  private static ObjectNode normalizeKeys(final ObjectNode genesis) {
-    final ObjectNode normalized = JsonUtil.createEmptyObjectNode();
-    genesis
-        .fields()
-        .forEachRemaining(
-            entry -> {
-              final String key = entry.getKey();
-              final JsonNode value = entry.getValue();
-              final String normalizedKey = key.toLowerCase(Locale.US);
-              if (value instanceof ObjectNode) {
-                normalized.set(normalizedKey, normalizeKeys((ObjectNode) value));
-              } else {
-                normalized.set(normalizedKey, value);
-              }
-            });
-    return normalized;
-  }
 }

config/src/main/java/tech/pegasys/pantheon/config/JsonUtil.java

@@ -13,6 +13,7 @@
 package tech.pegasys.pantheon.config;
 
 import java.io.IOException;
+import java.util.Locale;
 import java.util.Map;
 import java.util.Optional;
 import java.util.OptionalInt;
@@ -28,6 +29,32 @@ import com.fasterxml.jackson.databind.node.ObjectNode;
 
 public class JsonUtil {
 
+  /**
+   * Converts all the object keys (but none of the string values) to lowercase for easier lookup.
+   * This is useful in cases such as the 'genesis.json' file where all keys are assumed to be case
+   * insensitive.
+   *
+   * @param objectNode The ObjectNode to be normalized
+   * @return a copy of the json object with all keys in lower case.
+   */
+  public static ObjectNode normalizeKeys(final ObjectNode objectNode) {
+    final ObjectNode normalized = JsonUtil.createEmptyObjectNode();
+    objectNode
+        .fields()
+        .forEachRemaining(
+            entry -> {
+              final String key = entry.getKey();
+              final JsonNode value = entry.getValue();
+              final String normalizedKey = key.toLowerCase(Locale.US);
+              if (value instanceof ObjectNode) {
+                normalized.set(normalizedKey, normalizeKeys((ObjectNode) value));
+              } else {
+                normalized.set(normalizedKey, value);
+              }
+            });
+    return normalized;
+  }
+
   /**
    * Get the string representation of the value at {@code key}. For example, a numeric value like 5
    * will be returned as "5".
@@ -120,7 +147,7 @@ public class JsonUtil {
   }
 
   public static ObjectNode createEmptyObjectNode() {
-    ObjectMapper mapper = getObjectMapper();
+    final ObjectMapper mapper = getObjectMapper();
     return mapper.createObjectNode();
   }
 
@@ -140,7 +167,7 @@ public class JsonUtil {
       final JsonNode jsonNode = objectMapper.readTree(jsonData);
       validateType(jsonNode, JsonNodeType.OBJECT);
       return (ObjectNode) jsonNode;
-    } catch (IOException e) {
+    } catch (final IOException e) {
       // Reading directly from a string should not raise an IOException, just catch and rethrow
       throw new RuntimeException(e);
     }
@@ -152,7 +179,7 @@ public class JsonUtil {
 
   public static String getJson(final Object objectNode, final boolean prettyPrint)
       throws JsonProcessingException {
-    ObjectMapper mapper = getObjectMapper();
+    final ObjectMapper mapper = getObjectMapper();
     if (prettyPrint) {
       return mapper.writerWithDefaultPrettyPrinter().writeValueAsString(objectNode);
     } else {
@@ -209,7 +236,7 @@ public class JsonUtil {
   }
 
   private static Optional<JsonNode> getValue(final ObjectNode node, final String key) {
-    JsonNode jsonNode = node.get(key);
+    final JsonNode jsonNode = node.get(key);
     if (jsonNode == null || jsonNode.isNull()) {
       return Optional.empty();
     }

config/src/test/java/tech/pegasys/pantheon/config/JsonUtilTest.java

@@ -15,6 +15,8 @@ package tech.pegasys.pantheon.config;
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatThrownBy;
 
+import java.util.List;
+import java.util.Locale;
 import java.util.Map;
 import java.util.Optional;
 import java.util.OptionalInt;
@@ -29,7 +31,40 @@ import com.fasterxml.jackson.databind.node.ObjectNode;
 import org.junit.Test;
 
 public class JsonUtilTest {
-  private ObjectMapper mapper = new ObjectMapper();
+  private final ObjectMapper mapper = new ObjectMapper();
+
+  @Test
+  public void normalizeKeys_cases() {
+    final List<String> cases =
+        List.of(
+            "lower",
+            "CAPS",
+            "Proper",
+            "camelCase",
+            "snake_case",
+            "SHOUT_CASE",
+            "dash-case",
+            "!@#$%^&*(){}[]\\|-=_+;':\",.<>/?`~");
+    final ObjectNode base = mapper.createObjectNode();
+    for (final String s : cases) {
+      base.put(s, s);
+    }
+
+    final ObjectNode normalized = JsonUtil.normalizeKeys(base);
+    for (final String s : cases) {
+      assertThat(base.get(s).asText()).isEqualTo(normalized.get(s.toLowerCase(Locale.US)).asText());
+    }
+  }
+
+  @Test
+  public void normalizeKeys_depth() {
+    final ObjectNode base = mapper.createObjectNode();
+    base.putObject("DEEP").putObject("deeper").put("deeperER", "DEEPEST");
+
+    final ObjectNode normalized = JsonUtil.normalizeKeys(base);
+    assertThat(base.get("DEEP").get("deeper").get("deeperER").asText())
+        .isEqualTo(normalized.get("deep").get("deeper").get("deeperer").asText());
+  }
 
   @Test
   public void getLong_nonExistentKey() {
@@ -413,7 +448,7 @@ public class JsonUtilTest {
     subMap.put("d", 2L);
     map.put("subtree", subMap);
 
-    ObjectNode node = JsonUtil.objectNodeFromMap(map);
+    final ObjectNode node = JsonUtil.objectNodeFromMap(map);
     assertThat(node.get("a").asInt()).isEqualTo(1);
     assertThat(node.get("b").asInt()).isEqualTo(2);
     assertThat(node.get("subtree").get("c").asText()).isEqualTo("bla");