org.apache.beam.sdk.io.gcp.bigtable

Class BigtableIO

java.lang.Object

org.apache.beam.sdk.io.gcp.bigtable.BigtableIO

@Experimental(value=SOURCE_SINK)
public class BigtableIO
extends java.lang.Object

Transforms for reading from and writing to Google Cloud Bigtable.

For more information about Cloud Bigtable, see the online documentation at Google Cloud Bigtable.

Reading from Cloud Bigtable

The Bigtable source returns a set of rows from a single table, returning a PCollection<Row>.

To configure a Cloud Bigtable source, you must supply a table id, a project id, an instance id and optionally a BigtableOptions to provide more specific connection configuration. By default, BigtableIO.Read will read all rows in the table. The row ranges to be read can optionally be restricted using BigtableIO.Read.withKeyRanges(java.util.List<org.apache.beam.sdk.io.range.ByteKeyRange>), and a RowFilter can be specified using BigtableIO.Read.withRowFilter(com.google.bigtable.v2.RowFilter). For example:

 Pipeline p = ...;

 // Scan the entire table.
 p.apply("read",
     BigtableIO.read()
         .withProjectId(projectId)
         .withInstanceId(instanceId)
         .withTableId("table"));

 // Scan a prefix of the table.
 ByteKeyRange keyRange = ...;
 p.apply("read",
     BigtableIO.read()
         .withProjectId(projectId)
         .withInstanceId(instanceId)
         .withTableId("table")
         .withKeyRange(keyRange));

 // Scan a subset of rows that match the specified row filter.
 p.apply("filtered read",
     BigtableIO.read()
         .withProjectId(projectId)
         .withInstanceId(instanceId)
         .withTableId("table")
         .withRowFilter(filter));
 

Writing to Cloud Bigtable

The Bigtable sink executes a set of row mutations on a single table. It takes as input a PCollection<KV<ByteString, Iterable<Mutation>>>, where the ByteString is the key of the row being mutated, and each Mutation represents an idempotent transformation to that row.

To configure a Cloud Bigtable sink, you must supply a table id, a project id, an instance id and optionally a configuration function for BigtableOptions to provide more specific connection configuration, for example:

 PCollection<KV<ByteString, Iterable<Mutation>>> data = ...;

 data.apply("write",
     BigtableIO.write()
         .withProjectId("project")
         .withInstanceId("instance")
         .withTableId("table"));
 

Optionally, BigtableIO.write() may be configured to emit BigtableWriteResult elements after each group of inputs is written to Bigtable. These can be used to then trigger user code after writes have completed. See Wait for details on the windowing requirements of the signal and input PCollections.

 // See Wait.on
 PCollection<KV<ByteString, Iterable<Mutation>>> data = ...;

 PCollection<BigtableWriteResult> writeResults =
     data.apply("write",
         BigtableIO.write()
             .withProjectId("project")
             .withInstanceId("instance")
             .withTableId("table"))
             .withWriteResults();

 // The windowing of `moreData` must be compatible with `data`, see {@link org.apache.beam.sdk.transforms.Wait#on}
 // for details.
 PCollection<...> moreData = ...;

 moreData
     .apply("wait for writes", Wait.on(writeResults))
     .apply("do something", ParDo.of(...))

 

Experimental

This connector for Cloud Bigtable is considered experimental and may break or receive backwards-incompatible changes in future versions of the Apache Beam SDK. Cloud Bigtable is in Beta, and thus it may introduce breaking changes in future revisions of its service or APIs.

Permissions

Permission requirements depend on the PipelineRunner that is used to execute the pipeline. Please refer to the documentation of corresponding PipelineRunners for more details.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	BigtableIO.Read A PTransform that reads from Google Cloud Bigtable.
static class	BigtableIO.Write A PTransform that writes to Google Cloud Bigtable.
static class	BigtableIO.WriteWithResults A PTransform that writes to Google Cloud Bigtable and emits a BigtableWriteResult for each batch written.

Method Summary

Modifier and Type	Method and Description
static BigtableIO.Read	read() Creates an uninitialized BigtableIO.Read.
static BigtableIO.Write	write() Creates an uninitialized BigtableIO.Write.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

read

@Experimental
public static BigtableIO.Read read()

Creates an uninitialized BigtableIO.Read. Before use, the Read must be initialized with a BigtableIO.Read.withInstanceId(org.apache.beam.sdk.options.ValueProvider<java.lang.String>) and BigtableIO.Read.withProjectId(org.apache.beam.sdk.options.ValueProvider<java.lang.String>) that specifies the source Cloud Bigtable instance, and a BigtableIO.Read.withTableId(org.apache.beam.sdk.options.ValueProvider<java.lang.String>) that specifies which table to read. A RowFilter may also optionally be specified using BigtableIO.Read.withRowFilter(RowFilter).

write

@Experimental
public static BigtableIO.Write write()

Creates an uninitialized BigtableIO.Write. Before use, the Write must be initialized with a BigtableIO.Write.withProjectId(org.apache.beam.sdk.options.ValueProvider<java.lang.String>) and BigtableIO.Write.withInstanceId(org.apache.beam.sdk.options.ValueProvider<java.lang.String>) that specifies the destination Cloud Bigtable instance, and a BigtableIO.Write.withTableId(org.apache.beam.sdk.options.ValueProvider<java.lang.String>) that specifies which table to write.