Add beam package to open source build

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=178833972

java/google/registry/beam/InvoicingPipeline.java

@@ -0,0 +1,128 @@
+// Copyright 2017 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.beam;
+
+import google.registry.beam.BillingEvent.InvoiceGroupingKey;
+import google.registry.beam.BillingEvent.InvoiceGroupingKey.InvoiceGroupingKeyCoder;
+import google.registry.config.RegistryConfig.Config;
+import javax.inject.Inject;
+import org.apache.beam.runners.dataflow.DataflowRunner;
+import org.apache.beam.runners.dataflow.options.DataflowPipelineOptions;
+import org.apache.beam.sdk.Pipeline;
+import org.apache.beam.sdk.coders.SerializableCoder;
+import org.apache.beam.sdk.io.FileBasedSink;
+import org.apache.beam.sdk.io.TextIO;
+import org.apache.beam.sdk.io.gcp.bigquery.BigQueryIO;
+import org.apache.beam.sdk.options.Description;
+import org.apache.beam.sdk.options.PipelineOptionsFactory;
+import org.apache.beam.sdk.options.ValueProvider;
+import org.apache.beam.sdk.transforms.Count;
+import org.apache.beam.sdk.transforms.MapElements;
+import org.apache.beam.sdk.transforms.PTransform;
+import org.apache.beam.sdk.values.KV;
+import org.apache.beam.sdk.values.PCollection;
+import org.apache.beam.sdk.values.TypeDescriptor;
+import org.apache.beam.sdk.values.TypeDescriptors;
+
+/**
+ * Definition of a Dataflow pipeline template, which generates a given month's invoices.
+ *
+ * <p>To stage this template on GCS, run the {@link
+ * google.registry.tools.DeployInvoicingPipelineCommand} Nomulus command.
+ *
+ * <p>Then, you can run the staged template via the API client library, gCloud or a raw REST call.
+ * For an example using the API client library, see {@link
+ * google.registry.billing.GenerateInvoicesAction}.
+ *
+ * @see <a href="https://cloud.google.com/dataflow/docs/templates/overview">Dataflow Templates</a>
+ */
+public class InvoicingPipeline {
+
+  @Inject @Config("projectId") String projectId;
+  @Inject @Config("apacheBeamBucketUrl") String beamBucket;
+  @Inject InvoicingPipeline() {}
+
+  /** Custom options for running the invoicing pipeline. */
+  interface InvoicingPipelineOptions extends DataflowPipelineOptions {
+    /** Returns the yearMonth we're generating invoices for, in yyyy-MM format. */
+    @Description("The yearMonth we generate invoices for, in yyyy-MM format.")
+    ValueProvider<String> getYearMonth();
+    /** Sets the yearMonth we generate invoices for. */
+    void setYearMonth(ValueProvider<String> value);
+  }
+
+  /** Deploys the invoicing pipeline as a template on GCS, for a given projectID and GCS bucket. */
+  public void deploy() {
+    InvoicingPipelineOptions options = PipelineOptionsFactory.as(InvoicingPipelineOptions.class);
+    options.setProject(projectId);
+    options.setRunner(DataflowRunner.class);
+    options.setStagingLocation(beamBucket + "/staging");
+    options.setTemplateLocation(beamBucket + "/templates/invoicing");
+
+    Pipeline p = Pipeline.create(options);
+
+    PCollection<BillingEvent> billingEvents =
+        p.apply(
+            "Read BillingEvents from Bigquery",
+            BigQueryIO.read(BillingEvent::parseFromRecord)
+                .fromQuery(InvoicingUtils.makeQueryProvider(options.getYearMonth(), projectId))
+                .withCoder(SerializableCoder.of(BillingEvent.class))
+                .usingStandardSql()
+                .withoutValidation());
+
+    billingEvents.apply(
+        "Write events to separate CSVs keyed by registrarId_tld pair",
+        TextIO.<BillingEvent>writeCustomType()
+            .to(
+                InvoicingUtils.makeDestinationFunction(beamBucket + "/results"),
+                InvoicingUtils.makeEmptyDestinationParams(beamBucket + "/results"))
+            .withFormatFunction(BillingEvent::toCsv)
+            .withoutSharding()
+            .withTempDirectory(
+                FileBasedSink.convertToFileResourceIfPossible(beamBucket + "/temporary"))
+            .withHeader(BillingEvent.getHeader()));
+
+    billingEvents
+        .apply("Generate overall invoice rows", new GenerateInvoiceRows())
+        .apply(
+            "Write overall invoice to CSV",
+            TextIO.write()
+                .to(beamBucket + "/results/overall_invoice")
+                .withHeader(InvoiceGroupingKey.invoiceHeader())
+                .withoutSharding()
+                .withSuffix(".csv"));
+
+    p.run();
+  }
+
+  /** Transform that converts a {@code BillingEvent} into an invoice CSV row. */
+  static class GenerateInvoiceRows
+      extends PTransform<PCollection<BillingEvent>, PCollection<String>> {
+    @Override
+    public PCollection<String> expand(PCollection<BillingEvent> input) {
+      return input
+          .apply(
+              "Map to invoicing key",
+              MapElements.into(TypeDescriptor.of(InvoiceGroupingKey.class))
+                  .via(BillingEvent::getInvoiceGroupingKey))
+          .setCoder(new InvoiceGroupingKeyCoder())
+          .apply("Count occurrences", Count.perElement())
+          .apply(
+              "Format as CSVs",
+              MapElements.into(TypeDescriptors.strings())
+                  .via((KV<InvoiceGroupingKey, Long> kv) -> kv.getKey().toCsv(kv.getValue())));
+    }
+  }
+}