Add an abstract base class for single-shot account crawls

service/src/main/java/org/whispersystems/textsecuregcm/workers/AbstractSinglePassCrawlAccountsCommand.java

@@ -0,0 +1,64 @@
+/*
+ * Copyright 2023 Signal Messenger, LLC
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+package org.whispersystems.textsecuregcm.workers;
+
+import io.dropwizard.Application;
+import io.dropwizard.cli.EnvironmentCommand;
+import io.dropwizard.setup.Environment;
+import net.sourceforge.argparse4j.inf.Namespace;
+import net.sourceforge.argparse4j.inf.Subparser;
+import org.whispersystems.textsecuregcm.WhisperServerConfiguration;
+import org.whispersystems.textsecuregcm.metrics.MetricsUtil;
+import org.whispersystems.textsecuregcm.storage.Account;
+import org.whispersystems.textsecuregcm.util.logging.UncaughtExceptionHandler;
+import reactor.core.publisher.Flux;
+import java.util.Objects;
+
+public abstract class AbstractSinglePassCrawlAccountsCommand extends EnvironmentCommand<WhisperServerConfiguration> {
+
+  private CommandDependencies commandDependencies;
+
+  private static final String SEGMENT_COUNT = "segments";
+
+  public AbstractSinglePassCrawlAccountsCommand(final String name, final String description) {
+    super(new Application<>() {
+      @Override
+      public void run(final WhisperServerConfiguration configuration, final Environment environment) {
+      }
+    }, name, description);
+  }
+
+  @Override
+  public void configure(final Subparser subparser) {
+    super.configure(subparser);
+
+    subparser.addArgument("--segments")
+        .type(Integer.class)
+        .dest(SEGMENT_COUNT)
+        .required(false)
+        .setDefault(1)
+        .help("The total number of segments for a DynamoDB scan");
+  }
+
+  protected CommandDependencies getCommandDependencies() {
+    return commandDependencies;
+  }
+
+  @Override
+  protected void run(final Environment environment, final Namespace namespace,
+      final WhisperServerConfiguration configuration) throws Exception {
+
+    UncaughtExceptionHandler.register();
+
+    MetricsUtil.configureRegistries(configuration, environment);
+    commandDependencies = CommandDependencies.build(getName(), environment, configuration);
+
+    final int segments = Objects.requireNonNull(namespace.getInt(SEGMENT_COUNT));
+    crawlAccounts(commandDependencies.accountsManager().streamAllFromDynamo(segments));
+  }
+
+  protected abstract void crawlAccounts(final Flux<Account> accounts);
+}