Let tinkey output a help message when "tinkey help" is called.

At the same time:
- add "destroy-key" to TINKEY.md
- output the KeyTemplates in sorted order.

PiperOrigin-RevId: 506251200

4 files changed, 61 insertions, 9 deletions

diff --git a/tools/tinkey/src/main/java/com/google/crypto/tink/tinkey/BUILD.bazel b/tools/tinkey/src/main/java/com/google/crypto/tink/tinkey/BUILD.bazel
index bcebc5028..21c2a8204 100644
--- a/tools/tinkey/src/main/java/com/google/crypto/tink/tinkey/BUILD.bazel
+++ b/tools/tinkey/src/main/java/com/google/crypto/tink/tinkey/BUILD.bazel
@@ -62,6 +62,7 @@ java_library(
         ":destroy_key_command",
         ":disable_key_command",
         ":enable_key_command",
+        ":help_command",
         ":list_key_templates_command",
         ":list_keyset_command",
         ":promote_key_command",
@@ -299,3 +300,9 @@ java_library(
         "@tink_java//src/main/java/com/google/crypto/tink:key_templates",
     ],
 )
+
+java_library(
+    name = "help_command",
+    srcs = ["HelpCommand.java"],
+    deps = [":command"],
+)
diff --git a/tools/tinkey/src/main/java/com/google/crypto/tink/tinkey/HelpCommand.java b/tools/tinkey/src/main/java/com/google/crypto/tink/tinkey/HelpCommand.java
new file mode 100644
index 000000000..627d02b12
--- /dev/null
+++ b/tools/tinkey/src/main/java/com/google/crypto/tink/tinkey/HelpCommand.java
@@ -0,0 +1,41 @@
+// Copyright 2023 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.crypto.tink.tinkey;
+
+/** Outputs a help message. */
+public class HelpCommand implements Command {
+  @Override
+  public void run() throws Exception {
+    System.out.println("Tinkey supports the following commands:");
+    System.out.println("  help:                 Prints this help message.");
+    System.out.println("  add-key:              Generates and adds a new key to a keyset.");
+    System.out.println("  convert-keyset:       Changes format, encrypts, decrypts a keyset.");
+    System.out.println("  create-keyset:        Creates a new keyset.");
+    System.out.println("  create-public-keyset: Creates a public keyset from a private keyset.");
+    System.out.println("  list-key-templates:   Lists all supported key templates.");
+    System.out.println("  delete-key:           Deletes a specified key in a keyset.");
+    System.out.println(
+        "  destroy-key:          Destroys the key material of a specified key in a keyset.");
+    System.out.println("  disable-key:          Disables a specified key in a keyset.");
+    System.out.println("  enable-key:           Enables a specified key in a keyset.");
+    System.out.println("  list-keyset:          Lists keys in a keyset.");
+    System.out.println("  promote-key:          Promotes a specified key to primary.");
+    System.out.println(
+        "  rotate-keyset:        Deprecated. Rotate keysets in two steps using the commands"
+            + " 'add-key' and later 'promote-key'.");
+  }
+}
diff --git a/tools/tinkey/src/main/java/com/google/crypto/tink/tinkey/ListKeyTemplatesCommand.java b/tools/tinkey/src/main/java/com/google/crypto/tink/tinkey/ListKeyTemplatesCommand.java
index d3199bb4d..b4eadeb49 100644
--- a/tools/tinkey/src/main/java/com/google/crypto/tink/tinkey/ListKeyTemplatesCommand.java
+++ b/tools/tinkey/src/main/java/com/google/crypto/tink/tinkey/ListKeyTemplatesCommand.java
@@ -17,6 +17,9 @@
 package com.google.crypto.tink.tinkey;
 
 import com.google.crypto.tink.Registry;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
 
 /** Creates a new {@link com.google.crypto.tink.proto.KeyTemplate}. */
 public class ListKeyTemplatesCommand implements Command {
@@ -24,10 +27,11 @@ public class ListKeyTemplatesCommand implements Command {
   @Override
   public void run() throws Exception {
     System.out.println("The following key templates are supported:");
-    for (String name : Registry.keyTemplates()) {
-      System.out.println(name);
-    }
-    for (String name : TinkeyKeyTemplates.get().keySet()) {
+    List<String> keyTemplates = new ArrayList<>();
+    keyTemplates.addAll(Registry.keyTemplates());
+    keyTemplates.addAll(TinkeyKeyTemplates.get().keySet());
+    Collections.sort(keyTemplates);
+    for (String name : keyTemplates) {
       System.out.println(name);
     }
   }
diff --git a/tools/tinkey/src/main/java/com/google/crypto/tink/tinkey/TinkeyCommands.java b/tools/tinkey/src/main/java/com/google/crypto/tink/tinkey/TinkeyCommands.java
index e2c6f1e7b..75ed9ed12 100644
--- a/tools/tinkey/src/main/java/com/google/crypto/tink/tinkey/TinkeyCommands.java
+++ b/tools/tinkey/src/main/java/com/google/crypto/tink/tinkey/TinkeyCommands.java
@@ -26,12 +26,12 @@ import org.kohsuke.args4j.spi.SubCommands;
  */
 public final class TinkeyCommands {
   @Argument(
-    metaVar = "command",
-    required = true,
-    handler = SubCommandHandler.class,
-    usage = "Command to run"
-  )
+      metaVar = "command",
+      required = true,
+      handler = SubCommandHandler.class,
+      usage = "Command to run")
   @SubCommands({
+    @SubCommand(name = "help", impl = HelpCommand.class),
     @SubCommand(name = "add-key", impl = AddKeyCommand.class),
     @SubCommand(name = "convert-keyset", impl = ConvertKeysetCommand.class),
     @SubCommand(name = "create-keyset", impl = CreateKeysetCommand.class),