Add @SchemaFieldDescription annotations and description to Bigtable config (#36344)

* Add @SchemaFieldDescription annotations and description to Bigtable config fields

* Fix formatting using spotless

Author: namest504

sdks/java/io/google-cloud-platform/src/main/java/org/apache/beam/sdk/io/gcp/bigtable/BigtableReadSchemaTransformProvider.java

@@ -35,6 +35,7 @@
 import org.apache.beam.sdk.schemas.AutoValueSchema;
 import org.apache.beam.sdk.schemas.Schema;
 import org.apache.beam.sdk.schemas.annotations.DefaultSchema;
+import org.apache.beam.sdk.schemas.annotations.SchemaFieldDescription;
 import org.apache.beam.sdk.schemas.transforms.SchemaTransform;
 import org.apache.beam.sdk.schemas.transforms.SchemaTransformProvider;
 import org.apache.beam.sdk.schemas.transforms.TypedSchemaTransformProvider;
@@ -89,6 +90,19 @@ public String identifier() {
     return "beam:schematransform:org.apache.beam:bigtable_read:v1";
   }
 
+  @Override
+  public String description() {
+    return "Reads data from a Google Cloud Bigtable table.\n"
+        + "The transform requires the project ID, instance ID, and table ID parameters.\n"
+        + "Optionally, the output can be flattened or nested rows.\n"
+        + "Example usage:\n"
+        + "  - type: ReadFromBigTable\n"
+        + "    config:\n"
+        + "      project: \"my-gcp-project\"\n"
+        + "      instance: \"my-bigtable-instance\"\n"
+        + "      table: \"my-table\"\n";
+  }
+
   @Override
   public List<String> outputCollectionNames() {
     return Collections.singletonList(OUTPUT_TAG);
@@ -113,12 +127,17 @@ public static Builder builder() {
           .setFlatten(true);
     }
 
+    @SchemaFieldDescription("Bigtable table ID to read from.")
     public abstract String getTableId();
 
+    @SchemaFieldDescription("Bigtable instance ID to connect to.")
     public abstract String getInstanceId();
 
+    @SchemaFieldDescription("Google Cloud project ID containing the Bigtable instance.")
     public abstract String getProjectId();
 
+    @SchemaFieldDescription(
+        "If set to false, output rows are nested; if true or omitted, output rows are flattened.")
     public abstract @Nullable Boolean getFlatten();
 
     /** Builder for the {@link BigtableReadSchemaTransformConfiguration}. */

sdks/java/io/google-cloud-platform/src/main/java/org/apache/beam/sdk/io/gcp/bigtable/BigtableWriteSchemaTransformProvider.java

@@ -37,6 +37,7 @@
 import org.apache.beam.sdk.schemas.AutoValueSchema;
 import org.apache.beam.sdk.schemas.Schema;
 import org.apache.beam.sdk.schemas.annotations.DefaultSchema;
+import org.apache.beam.sdk.schemas.annotations.SchemaFieldDescription;
 import org.apache.beam.sdk.schemas.transforms.SchemaTransform;
 import org.apache.beam.sdk.schemas.transforms.SchemaTransformProvider;
 import org.apache.beam.sdk.schemas.transforms.TypedSchemaTransformProvider;
@@ -83,6 +84,20 @@ public String identifier() {
     return "beam:schematransform:org.apache.beam:bigtable_write:v1";
   }
 
+  @Override
+  public String description() {
+    return "Writes data to a Google Cloud Bigtable table.\n"
+        + "This transform requires the Google Cloud project ID, Bigtable instance ID, and table ID.\n"
+        + "The input PCollection should be schema-compliant mutations or keyed rows.\n"
+        + "Example usage:\n"
+        + "  - type: WriteToBigTable\n"
+        + "    input: input\n"
+        + "    config:\n"
+        + "      project: \"my-gcp-project\"\n"
+        + "      instance: \"my-bigtable-instance\"\n"
+        + "      table: \"my-table\"\n";
+  }
+
   @Override
   public List<String> inputCollectionNames() {
     return Collections.singletonList(INPUT_TAG);
@@ -108,10 +123,13 @@ public void validate() {
       checkArgument(!this.getProjectId().isEmpty(), String.format(invalidConfigMessage, "project"));
     }
 
+    @SchemaFieldDescription("Bigtable table ID to write data into.")
     public abstract String getTableId();
 
+    @SchemaFieldDescription("Bigtable instance ID where the table is located.")
     public abstract String getInstanceId();
 
+    @SchemaFieldDescription("Google Cloud project ID containing the Bigtable instance.")
     public abstract String getProjectId();
 
     /** Builder for the {@link BigtableWriteSchemaTransformConfiguration}. */