Add a new check API that does not wrap the domain check EPP flow

Copied class and test from CheckApiAction. All unit tests passing.

Remaining work: add metrics

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=198916177

javatests/google/registry/flows/CheckApi2ActionTest.java

@@ -0,0 +1,182 @@
+// Copyright 2018 The Nomulus Authors. All Rights Reserved.
+//
+// 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 google.registry.flows;
+
+import static com.google.common.truth.Truth.assertThat;
+import static google.registry.testing.DatastoreHelper.createTld;
+import static google.registry.testing.DatastoreHelper.persistActiveDomain;
+import static google.registry.testing.DatastoreHelper.persistReservedList;
+import static google.registry.testing.DatastoreHelper.persistResource;
+
+import google.registry.model.registry.Registry;
+import google.registry.model.registry.Registry.TldState;
+import google.registry.testing.AppEngineRule;
+import google.registry.testing.FakeClock;
+import google.registry.testing.FakeResponse;
+import java.util.Map;
+import org.json.simple.JSONValue;
+import org.junit.Before;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+/** Tests for {@link CheckApi2Action}. */
+@RunWith(JUnit4.class)
+public class CheckApi2ActionTest {
+
+  @Rule public final AppEngineRule appEngine = AppEngineRule.builder().withDatastore().build();
+
+  @Before
+  public void init() throws Exception {
+    createTld("example");
+    persistResource(
+        Registry.get("example")
+            .asBuilder()
+            .setReservedLists(persistReservedList("example-reserved", "foo,FULLY_BLOCKED"))
+            .build());
+  }
+
+  @SuppressWarnings("unchecked")
+  private Map<String, Object> getCheckResponse(String domain) {
+    CheckApi2Action action = new CheckApi2Action();
+    action.domain = domain;
+    action.response = new FakeResponse();
+    action.clock = new FakeClock();
+    action.run();
+    return (Map<String, Object>) JSONValue.parse(((FakeResponse) action.response).getPayload());
+  }
+
+  @Test
+  public void testFailure_nullDomain() throws Exception {
+    assertThat(getCheckResponse(null))
+        .containsExactly(
+            "status", "error",
+            "reason", "Must supply a valid domain name on an authoritative TLD");
+  }
+
+  @Test
+  public void testFailure_emptyDomain() throws Exception {
+    assertThat(getCheckResponse(""))
+        .containsExactly(
+            "status", "error",
+            "reason", "Must supply a valid domain name on an authoritative TLD");
+  }
+
+  @Test
+  public void testFailure_invalidDomain() throws Exception {
+    assertThat(getCheckResponse("@#$%^"))
+        .containsExactly(
+            "status", "error",
+            "reason", "Must supply a valid domain name on an authoritative TLD");
+  }
+
+  @Test
+  public void testFailure_singlePartDomain() throws Exception {
+    assertThat(getCheckResponse("foo"))
+        .containsExactly(
+            "status", "error",
+            "reason", "Must supply a valid domain name on an authoritative TLD");
+  }
+
+  @Test
+  public void testFailure_nonExistentTld() throws Exception {
+    assertThat(getCheckResponse("foo.bar"))
+        .containsExactly(
+            "status", "error",
+            "reason", "Must supply a valid domain name on an authoritative TLD");
+  }
+
+  @Test
+  public void testFailure_invalidIdnTable() throws Exception {
+    assertThat(getCheckResponse("ΑΒΓ.example"))
+        .containsExactly(
+            "status", "error",
+            "reason", "Domain label is not allowed by IDN table");
+  }
+
+  @Test
+  public void testFailure_tldInPredelegation() throws Exception {
+    createTld("predelegated", TldState.PREDELEGATION);
+    assertThat(getCheckResponse("foo.predelegated"))
+        .containsExactly(
+            "status", "error",
+            "reason", "Check in this TLD is not allowed in the current registry phase");
+  }
+
+  @Test
+  public void testSuccess_availableStandard() throws Exception {
+    assertThat(getCheckResponse("somedomain.example"))
+        .containsExactly(
+            "status", "success",
+            "available", true,
+            "tier", "standard");
+  }
+
+  @Test
+  public void testSuccess_availableCapital() throws Exception {
+    assertThat(getCheckResponse("SOMEDOMAIN.EXAMPLE"))
+        .containsExactly(
+            "status", "success",
+            "available", true,
+            "tier", "standard");
+  }
+
+  @Test
+  public void testSuccess_availableUnicode() throws Exception {
+    assertThat(getCheckResponse("ééé.example"))
+        .containsExactly(
+            "status", "success",
+            "available", true,
+            "tier", "standard");
+  }
+
+  @Test
+  public void testSuccess_availablePunycode() throws Exception {
+    assertThat(getCheckResponse("xn--9caaa.example"))
+        .containsExactly(
+            "status", "success",
+            "available", true,
+            "tier", "standard");
+  }
+
+  @Test
+  public void testSuccess_availablePremium() throws Exception {
+    assertThat(getCheckResponse("rich.example"))
+        .containsExactly(
+            "status", "success",
+            "available", true,
+            "tier", "premium");
+  }
+
+  @Test
+  public void testSuccess_alreadyRegistered() throws Exception {
+    persistActiveDomain("somedomain.example");
+    assertThat(getCheckResponse("somedomain.example"))
+        .containsExactly(
+            "status", "success",
+            "available", false,
+            "reason", "In use");
+  }
+
+  @Test
+  public void testSuccess_reserved() throws Exception {
+    assertThat(getCheckResponse("foo.example"))
+        .containsExactly(
+            "status", "success",
+            "available", false,
+            "reason", "Reserved");
+  }
+}