Examples with KeyValue com.yahoo.pulsar.common.api.proto.PulsarApi.KeyValue used on opensource projects

Example 1 with KeyValue

use of com.yahoo.pulsar.common.api.proto.PulsarApi.KeyValue in project pulsar by yahoo.

the class PersistentTopics method peekNthMessage.

@GET
@Path("/{property}/{cluster}/{namespace}/{destination}/subscription/{subName}/position/{messagePosition}")
@ApiOperation(value = "Peek nth message on a topic subscription.")
@ApiResponses(value = { @ApiResponse(code = 403, message = "Don't have admin permission"), @ApiResponse(code = 404, message = "Topic, subscription or the message position does not exist") })
public Response peekNthMessage(@PathParam("property") String property, @PathParam("cluster") String cluster, @PathParam("namespace") String namespace, @PathParam("destination") @Encoded String destination, @PathParam("subName") String subName, @PathParam("messagePosition") int messagePosition, @QueryParam("authoritative") @DefaultValue("false") boolean authoritative) {
    destination = decode(destination);
    DestinationName dn = DestinationName.get(domain(), property, cluster, namespace, destination);
    PartitionedTopicMetadata partitionMetadata = getPartitionedTopicMetadata(property, cluster, namespace, destination, authoritative);
    if (partitionMetadata.partitions > 0) {
        throw new RestException(Status.METHOD_NOT_ALLOWED, "Peek messages on a partitioned topic is not allowed");
    }
    validateAdminOperationOnDestination(dn, authoritative);
    PersistentTopic topic = getTopicReference(dn);
    PersistentReplicator repl = null;
    PersistentSubscription sub = null;
    Entry entry = null;
    if (subName.startsWith(topic.replicatorPrefix)) {
        repl = getReplicatorReference(subName, topic);
    } else {
        sub = getSubscriptionReference(subName, topic);
    }
    try {
        if (subName.startsWith(topic.replicatorPrefix)) {
            entry = repl.peekNthMessage(messagePosition).get();
        } else {
            entry = sub.peekNthMessage(messagePosition).get();
        }
        checkNotNull(entry);
        PositionImpl pos = (PositionImpl) entry.getPosition();
        ByteBuf metadataAndPayload = entry.getDataBuffer();
        // moves the readerIndex to the payload
        MessageMetadata metadata = Commands.parseMessageMetadata(metadataAndPayload);
        ResponseBuilder responseBuilder = Response.ok();
        responseBuilder.header("X-Pulsar-Message-ID", pos.toString());
        for (KeyValue keyValue : metadata.getPropertiesList()) {
            responseBuilder.header("X-Pulsar-PROPERTY-" + keyValue.getKey(), keyValue.getValue());
        }
        if (metadata.hasPublishTime()) {
            responseBuilder.header("X-Pulsar-publish-time", DATE_FORMAT.format(Instant.ofEpochMilli(metadata.getPublishTime())));
        }
        // Decode if needed
        CompressionCodec codec = CompressionCodecProvider.getCompressionCodec(metadata.getCompression());
        ByteBuf uncompressedPayload = codec.decode(metadataAndPayload, metadata.getUncompressedSize());
        // Copy into a heap buffer for output stream compatibility
        ByteBuf data = PooledByteBufAllocator.DEFAULT.heapBuffer(uncompressedPayload.readableBytes(), uncompressedPayload.readableBytes());
        data.writeBytes(uncompressedPayload);
        uncompressedPayload.release();
        StreamingOutput stream = new StreamingOutput() {

            @Override
            public void write(OutputStream output) throws IOException, WebApplicationException {
                output.write(data.array(), data.arrayOffset(), data.readableBytes());
                data.release();
            }
        };
        return responseBuilder.entity(stream).build();
    } catch (NullPointerException npe) {
        throw new RestException(Status.NOT_FOUND, "Message not found");
    } catch (Exception exception) {
        log.error("[{}] Failed to get message at position {} from {} {}", clientAppId(), messagePosition, dn, subName, exception);
        throw new RestException(exception);
    } finally {
        if (entry != null) {
            entry.release();
        }
    }
}