test: add Spanner JSON test suite (#1376)

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Fixes #<issue_number_goes_here> ☕️

Author: zoercai

google-cloud-spanner/src/test/java/com/google/cloud/spanner/it/ITJsonWriteReadTest.java

@@ -0,0 +1,151 @@
+/*
+ * Copyright 2021 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.cloud.spanner.it;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertThrows;
+import static org.junit.Assume.assumeFalse;
+
+import com.google.cloud.spanner.Database;
+import com.google.cloud.spanner.DatabaseClient;
+import com.google.cloud.spanner.IntegrationTestEnv;
+import com.google.cloud.spanner.Mutation;
+import com.google.cloud.spanner.ParallelIntegrationTest;
+import com.google.cloud.spanner.ResultSet;
+import com.google.cloud.spanner.SpannerException;
+import com.google.cloud.spanner.Statement;
+import com.google.cloud.spanner.Value;
+import com.google.cloud.spanner.testing.EmulatorSpannerHelper;
+import com.google.cloud.spanner.testing.RemoteSpannerHelper;
+import com.google.common.io.Resources;
+import java.io.File;
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.concurrent.atomic.AtomicLong;
+import java.util.stream.Collectors;
+import org.junit.BeforeClass;
+import org.junit.ClassRule;
+import org.junit.Test;
+import org.junit.experimental.categories.Category;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+@Category(ParallelIntegrationTest.class)
+@RunWith(JUnit4.class)
+public class ITJsonWriteReadTest {
+
+  private static final String RESOURCES_DIR = "com/google/cloud/spanner/it/";
+  private static final String VALID_JSON_DIR = "valid";
+  private static final String INVALID_JSON_DIR = "invalid";
+
+  private static final String TABLE_NAME = "TestTable";
+
+  @ClassRule public static IntegrationTestEnv env = new IntegrationTestEnv();
+
+  private static DatabaseClient databaseClient;
+
+  @BeforeClass
+  public static void beforeClass() {
+    final RemoteSpannerHelper testHelper = env.getTestHelper();
+    if (!EmulatorSpannerHelper.isUsingEmulator()) {
+      final Database database =
+          testHelper.createTestDatabase(
+              "CREATE TABLE "
+                  + TABLE_NAME
+                  + "("
+                  + "Id INT64 NOT NULL,"
+                  + "json JSON"
+                  + ") PRIMARY KEY (Id)");
+      databaseClient = testHelper.getDatabaseClient(database);
+    }
+  }
+
+  @Test
+  public void testWriteValidJsonValues() throws IOException {
+    assumeFalse("Emulator does not yet support JSON", EmulatorSpannerHelper.isUsingEmulator());
+
+    List<String> resources = getJsonFilePaths(RESOURCES_DIR + File.separator + VALID_JSON_DIR);
+
+    long id = 0L;
+    List<Mutation> mutations = new ArrayList<>();
+    for (String resource : resources) {
+      String jsonStr =
+          Resources.toString(
+              Resources.getResource(this.getClass(), VALID_JSON_DIR + File.separator + resource),
+              StandardCharsets.UTF_8);
+      Mutation mutation =
+          Mutation.newInsertBuilder(TABLE_NAME)
+              .set("Id")
+              .to(id++)
+              .set("json")
+              .to(Value.json(jsonStr))
+              .build();
+      mutations.add(mutation);
+    }
+    databaseClient.write(mutations);
+
+    try (ResultSet resultSet =
+        databaseClient
+            .singleUse()
+            .executeQuery(Statement.of("SELECT COUNT(*) FROM " + TABLE_NAME))) {
+      resultSet.next();
+      assertEquals(resultSet.getLong(0), resources.size());
+    }
+  }
+
+  @Test
+  public void testWriteAndReadInvalidJsonValues() throws IOException {
+    assumeFalse("Emulator does not yet support JSON", EmulatorSpannerHelper.isUsingEmulator());
+
+    List<String> resources = getJsonFilePaths(RESOURCES_DIR + File.separator + INVALID_JSON_DIR);
+
+    AtomicLong id = new AtomicLong(100);
+    for (String resource : resources) {
+      String jsonStr =
+          Resources.toString(
+              Resources.getResource(this.getClass(), INVALID_JSON_DIR + File.separator + resource),
+              StandardCharsets.UTF_8);
+      assertThrows(
+          SpannerException.class,
+          () ->
+              databaseClient.write(
+                  Collections.singletonList(
+                      Mutation.newInsertBuilder(TABLE_NAME)
+                          .set("Id")
+                          .to(id.getAndIncrement())
+                          .set("json")
+                          .to(Value.json(jsonStr))
+                          .build())));
+    }
+  }
+
+  private List<String> getJsonFilePaths(String folder) throws IOException {
+    String fixturesRoot = Resources.getResource(folder).getPath();
+    final Path fixturesRootPath = Paths.get(fixturesRoot);
+    return Files.walk(fixturesRootPath)
+        .filter(Files::isRegularFile)
+        .map(path -> fixturesRootPath.relativize(path).toString())
+        .filter(path -> path.endsWith(".json"))
+        .collect(Collectors.toList());
+  }
+}

google-cloud-spanner/src/test/resources/com/google/cloud/spanner/it/invalid/n_array_1_true_without_comma.json

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+[1 true]

google-cloud-spanner/src/test/resources/com/google/cloud/spanner/it/invalid/n_array_a_invalid_utf8.json

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+[a�]

google-cloud-spanner/src/test/resources/com/google/cloud/spanner/it/invalid/n_array_colon_instead_of_comma.json

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+["": 1]

google-cloud-spanner/src/test/resources/com/google/cloud/spanner/it/invalid/n_array_comma_after_close.json

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+[""],

google-cloud-spanner/src/test/resources/com/google/cloud/spanner/it/invalid/n_array_comma_and_number.json

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+[,1]

google-cloud-spanner/src/test/resources/com/google/cloud/spanner/it/invalid/n_array_double_comma.json

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+[1,,2]

google-cloud-spanner/src/test/resources/com/google/cloud/spanner/it/invalid/n_array_double_extra_comma.json

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+["x",,]

google-cloud-spanner/src/test/resources/com/google/cloud/spanner/it/invalid/n_array_extra_close.json

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+["x"]]

google-cloud-spanner/src/test/resources/com/google/cloud/spanner/it/invalid/n_array_extra_comma.json

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+["",]