Add RFC6901 json pointer support

src/main/java/com/redislabs/modules/rejson/Path.java

@@ -28,13 +28,15 @@
 
 package com.redislabs.modules.rejson;
 
+import java.util.Objects;
+
 /**
  * Path is a ReJSON path, representing a valid path into an object
  */
 public class Path {
-
-public static final Path ROOT_PATH = new Path(".");
-
+
+public static final Path ROOT_PATH = new Path(".");
+
  private final String strPath;
 
  public Path(final String strPath) {
@@ -60,6 +62,10 @@ public static Path of(final String strPath) {
  return new Path(strPath);
  }
 
+ public static Path ofJsonPointer(final String strPath) {
+ return new Path(parse(strPath));
+ }
+
  @Override
  public boolean equals(Object obj) {
  if (obj == null) return false;
@@ -72,4 +78,87 @@ public boolean equals(Object obj) {
  public int hashCode() {
  return strPath.hashCode();
  }
+
+ private static String parse(String path) {
+ Objects.requireNonNull(path, "Json Pointer Path cannot be null.");
+
+ if (path.isEmpty()) {
+ // "" means all document 
+ return ROOT_PATH.toString();
+ }
+ if (path.charAt(0) != '/') {
+ throw new IllegalArgumentException("Json Pointer Path must start with '/'.");
+ }
+
+ final char[] ary = path.toCharArray();
+ StringBuilder result = new StringBuilder();
+ StringBuilder builder = new StringBuilder();
+ boolean number = true;
+ char prev = '/';
+ for (int i = 1; i < ary.length; i++) {
+ char c = ary[i];
+ switch (c) {
+ case '~':
+ if (prev == '~') {
+ number = false;
+ builder.append('~');
+ }
+ break;
+ case '/':
+ if (prev == '~') {
+ number = false;
+ builder.append('~');
+ }
+ if (builder.length() > 0 && number) {
+ result.append(".[").append(builder).append("]");
+ } else {
+ result.append(".[\"").append(builder).append("\"]");
+ }
+ number = true;
+ builder.setLength(0);
+ break;
+ case '0':
+ if (prev == '~') {
+ number = false;
+ builder.append("~");
+ } else {
+ builder.append(c);
+ }
+ break;
+ case '1':
+ if (prev == '~') {
+ number = false;
+ builder.append("/");
+ } else {
+ builder.append(c);
+ }
+ break;
+ default:
+ if (prev == '~') {
+ number = false;
+ builder.append('~');
+ }
+ if (c < '0' || c > '9') {
+ number = false;
+ }
+ builder.append(c);
+ break;
+ }
+ prev = c;
+ }
+ if (prev == '~') {
+ number = false;
+ builder.append("~");
+ }
+ if (builder.length() > 0) {
+ if (number) {
+ result.append(".[").append(builder).append("]");
+ } else {
+ result.append(".[\"").append(builder).append("\"]");
+ }
+ } else if (prev == '/') {
+ result.append(".[\"").append(builder).append("\"]");
+ }
+ return result.toString();
+ }
 }

src/test/java/com/redislabs/modules/rejson/PathTest.java

@@ -31,4 +31,38 @@ public void testPathHashCode() {
  assertEquals(Path.of(".a.b.c").hashCode(), Path.of(".a.b.c").hashCode());
  assertNotEquals(Path.of(".a.b.c").hashCode(), Path.of(".b.c").hashCode());
  }
+
+ @Test
+ public void testJsonPointer() {
+ assertEquals(Path.ofJsonPointer(""), Path.ROOT_PATH);
+ assertEquals(Path.ofJsonPointer("/"), Path.of(".[\"\"]"));
+ assertEquals(Path.ofJsonPointer("//0"), Path.of(".[\"\"].[0]"));
+ assertEquals(Path.ofJsonPointer("//"), Path.of(".[\"\"].[\"\"]"));
+ assertEquals(Path.ofJsonPointer("// "), Path.of(".[\"\"].[\" \"]"));
+ assertEquals(Path.ofJsonPointer("/a/b/c"), Path.of(".[\"a\"].[\"b\"].[\"c\"]"));
+ assertEquals(Path.ofJsonPointer("/a/0/c"), Path.of(".[\"a\"].[0].[\"c\"]"));
+ assertEquals(Path.ofJsonPointer("/a/0b/c"), Path.of(".[\"a\"].[\"0b\"].[\"c\"]"));
+ assertEquals(Path.ofJsonPointer("/ab/cd/1010"), Path.of(".[\"ab\"].[\"cd\"].[1010]"));
+ assertEquals(Path.ofJsonPointer("/a/b/c").hashCode(), Path.of(".[\"a\"].[\"b\"].[\"c\"]").hashCode());
+
+ // escape test
+ assertEquals(Path.ofJsonPointer("/a/~0"), Path.of(".[\"a\"].[\"~\"]"));
+ assertEquals(Path.ofJsonPointer("/a/~1"), Path.of(".[\"a\"].[\"/\"]"));
+ assertEquals(Path.ofJsonPointer("/a/~0/c"), Path.of(".[\"a\"].[\"~\"].[\"c\"]"));
+ assertEquals(Path.ofJsonPointer("/a/~1/c"), Path.of(".[\"a\"].[\"/\"].[\"c\"]"));
+ assertEquals(Path.ofJsonPointer("/a/~~/c"), Path.of(".[\"a\"].[\"~~\"].[\"c\"]"));
+ assertEquals(Path.ofJsonPointer("/~/~~~/~"), Path.of(".[\"~\"].[\"~~~\"].[\"~\"]"));
+ assertEquals(Path.ofJsonPointer("/~/~~~/~~"), Path.of(".[\"~\"].[\"~~~\"].[\"~~\"]"));
+ assertEquals(Path.ofJsonPointer("/~/~~~0/~~"), Path.of(".[\"~\"].[\"~~~\"].[\"~~\"]"));
+ assertEquals(Path.ofJsonPointer("/~/'.'/~~"), Path.of(".[\"~\"].[\"'.'\"].[\"~~\"]"));
+
+ // json path escape test
+ assertEquals(Path.ofJsonPointer("/\t"), Path.of(".[\"\t\"]"));
+ assertEquals(Path.ofJsonPointer("/\u0074"), Path.of(".[\"\u0074\"]"));
+ assertEquals(Path.ofJsonPointer("/'"), Path.of(".[\"'\"]"));
+ assertEquals(Path.ofJsonPointer("/\'"), Path.of(".[\"\'\"]"));
+ assertEquals(Path.ofJsonPointer("/\""), Path.of(".[\"\"\"]"));
+ assertEquals(Path.ofJsonPointer("/\n"), Path.of(".[\"\n\"]"));
+ assertEquals(Path.ofJsonPointer("/\\"), Path.of(".[\"\\\"]"));
+ }
 }