Add command for creating LRP tokens

Command allows for both one-off creation and bulk import of assignees via file (the latter will be used for the initial import from Play Store).

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=133048360

java/google/registry/tools/CreateLrpTokensCommand.java

@@ -0,0 +1,152 @@
+// Copyright 2016 The Domain Registry 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.tools;
+
+import static com.google.common.base.Preconditions.checkArgument;
+import static com.google.common.base.Strings.isNullOrEmpty;
+import static com.google.common.collect.Sets.difference;
+import static google.registry.model.ofy.ObjectifyService.ofy;
+import static google.registry.model.registry.Registries.assertTldExists;
+import static java.nio.charset.StandardCharsets.UTF_8;
+
+import com.beust.jcommander.Parameter;
+import com.beust.jcommander.Parameters;
+
+import com.google.common.base.Function;
+import com.google.common.base.Splitter;
+import com.google.common.collect.FluentIterable;
+import com.google.common.collect.ImmutableSet;
+import com.google.common.io.Files;
+import com.google.common.io.LineReader;
+
+import com.googlecode.objectify.Key;
+import com.googlecode.objectify.Work;
+
+import google.registry.model.domain.LrpToken;
+import google.registry.tools.Command.GtechCommand;
+import google.registry.tools.Command.RemoteApiCommand;
+import google.registry.tools.params.PathParameter;
+
+import java.io.StringReader;
+import java.nio.file.Path;
+import java.util.Collection;
+import java.util.Set;
+
+import javax.inject.Inject;
+
+/**
+ * Command to create one or more LRP tokens, given assignee(s) as either a parameter or a text file.
+ */
+@Parameters(
+    separators = " =",
+    commandDescription = "Create an LRP token for a given assignee (using -a) or import a text"
+        + " file of assignees for bulk token creation (using -i). Assignee/token pairs are printed"
+        + " to stdout, and should be piped to a file for distribution to assignees or for cleanup"
+        + " in the event of a command interruption.")
+public final class CreateLrpTokensCommand implements RemoteApiCommand, GtechCommand {
+
+  @Parameter(
+      names = {"-a", "--assignee"},
+      description = "LRP token assignee")
+  private String assignee;
+
+  @Parameter(
+      names = {"-t", "--tlds"},
+      description = "Comma-delimited list of TLDs that the tokens to create will be valid on",
+      required = true)
+  private String tlds;
+
+  @Parameter(
+      names = {"-i", "--input"},
+      description = "Filename containing a list of assignees, newline-delimited",
+      validateWith = PathParameter.InputFile.class)
+  private Path assigneesFile;
+
+  @Inject StringGenerator stringGenerator;
+
+  private static final int TOKEN_LENGTH = 16;
+  private static final int BATCH_SIZE = 20;
+
+  @Override
+  public void run() throws Exception {
+    checkArgument(
+        (assignee == null) == (assigneesFile != null),
+        "Exactly one of either assignee or filename must be specified.");
+    final Set<String> validTlds = ImmutableSet.copyOf(Splitter.on(',').split(tlds));
+    for (String tld : validTlds) {
+      assertTldExists(tld);
+    }
+
+    LineReader reader = new LineReader(
+        (assignee == null)
+            ? Files.newReader(assigneesFile.toFile(), UTF_8)
+            : new StringReader(assignee));
+
+    String line = null;
+    do {
+      ImmutableSet.Builder<LrpToken> tokensToSave = new ImmutableSet.Builder<>();
+      for (String token : generateTokens(BATCH_SIZE)) {
+        line = reader.readLine();
+        if (!isNullOrEmpty(line)) {
+          tokensToSave.add(new LrpToken.Builder()
+              .setAssignee(line)
+              .setToken(token)
+              .setValidTlds(validTlds)
+              .build());
+        }
+      }
+      saveTokens(tokensToSave.build());
+    } while (line != null);
+  }
+
+  private void saveTokens(final ImmutableSet<LrpToken> tokens) {
+    Collection<LrpToken> savedTokens = ofy().transact(new Work<Collection<LrpToken>>() {
+      @Override
+      public Collection<LrpToken> run() {
+        return ofy().save().entities(tokens).now().values();
+      }});
+    for (LrpToken token : savedTokens) {
+      System.out.printf("%s,%s%n", token.getAssignee(), token.getToken());
+    }
+  }
+
+  /**
+   * This function generates at MOST {@code count} tokens, after filtering out any token strings
+   * that already exist.
+   * 
+   * <p>Note that in the incredibly rare case that all generated tokens already exist, this function
+   * may return an empty set.
+   */
+  private ImmutableSet<String> generateTokens(int count) {
+    final ImmutableSet<String> candidates =
+        ImmutableSet.copyOf(stringGenerator.createStrings(TOKEN_LENGTH, count));
+    ImmutableSet<Key<LrpToken>> existingTokenKeys = FluentIterable.from(candidates)
+        .transform(new Function<String, Key<LrpToken>>() {
+          @Override
+          public Key<LrpToken> apply(String input) {
+            return Key.create(LrpToken.class, input);
+          }})
+        .toSet();
+    ImmutableSet<String> existingTokenStrings = FluentIterable
+        .from(ofy().load().keys(existingTokenKeys).values())
+        .transform(new Function<LrpToken, String>() {
+          @Override
+          public String apply(LrpToken input) {
+            return input.getToken();
+          }})
+        .toSet();
+    return ImmutableSet.copyOf(difference(candidates, existingTokenStrings));
+  }
+}