[[aws2-ddbstream-component]]
= AWS DynamoDB Streams Component
//THIS FILE IS COPIED: EDIT THE SOURCE FILE:
:page-source: components/camel-aws/camel-aws2-ddb/src/main/docs/aws2-ddbstream-component.adoc
:docTitle: AWS DynamoDB Streams
:artifactId: camel-aws2-ddb
:description: Receive messages from AWS DynamoDB Stream service using AWS SDK version 2.x.
:since: 3.1
:supportLevel: Stable
:component-header: Only consumer is supported
include::{cq-version}@camel-quarkus:ROOT:partial$reference/components/aws2-ddbstream.adoc[opts=optional]
//Manually maintained attributes
:group: AWS

*Since Camel {since}*

*{component-header}*

The AWS2 DynamoDB Stream component supports receiving messages from
Amazon DynamoDB Stream service.

Prerequisites

You must have a valid Amazon Web Services developer account, and be
signed up to use Amazon DynamoDB Streams. More information are available
at https://aws.amazon.com/dynamodb/[AWS DynamoDB]

[NOTE]
====
The AWS2 DynamoDB Streams component is not supported in OSGI
====

== URI Format

[source,java]
------------------------------------
aws2-ddbstream://table-name[?options]
------------------------------------

The stream needs to be created prior to it being used. +
 You can append query options to the URI in the following format,
?options=value&option2=value&...

== URI Options


// component options: START
The AWS DynamoDB Streams component supports 17 options, which are listed below.



[width="100%",cols="2,5,^1,2",options="header"]
|===
| Name | Description | Default | Type
| *amazonDynamoDbStreamsClient* (consumer) | *Autowired* Amazon DynamoDB client to use for all requests for this endpoint |  | DynamoDbStreamsClient
| *bridgeErrorHandler* (consumer) | Allows for bridging the consumer to the Camel routing Error Handler, which mean any exceptions occurred while the consumer is trying to pickup incoming messages, or the likes, will now be processed as a message and handled by the routing Error Handler. By default the consumer will use the org.apache.camel.spi.ExceptionHandler to deal with exceptions, that will be logged at WARN or ERROR level and ignored. | false | boolean
| *configuration* (consumer) | The component configuration |  | Ddb2StreamConfiguration
| *iteratorType* (consumer) | Defines where in the DynaboDB stream to start getting records. Note that using TRIM_HORIZON can cause a significant delay before the stream has caught up to real-time. if {AT,AFTER}_SEQUENCE_NUMBER are used, then a sequenceNumberProvider MUST be supplied. There are 5 enums and the value can be one of: TRIM_HORIZON, LATEST, AT_SEQUENCE_NUMBER, AFTER_SEQUENCE_NUMBER, null | LATEST | ShardIteratorType
| *maxResultsPerRequest* (consumer) | Maximum number of records that will be fetched in each poll |  | int
| *overrideEndpoint* (consumer) | Set the need for overidding the endpoint. This option needs to be used in combination with uriEndpointOverride option | false | boolean
| *proxyHost* (consumer) | To define a proxy host when instantiating the DDBStreams client |  | String
| *proxyPort* (consumer) | To define a proxy port when instantiating the DDBStreams client |  | Integer
| *proxyProtocol* (consumer) | To define a proxy protocol when instantiating the DDBStreams client. There are 2 enums and the value can be one of: HTTP, HTTPS | HTTPS | Protocol
| *region* (consumer) | The region in which DDBStreams client needs to work |  | String
| *sequenceNumberProvider* (consumer) | Provider for the sequence number when using one of the two ShardIteratorType.{AT,AFTER}_SEQUENCE_NUMBER iterator types. Can be a registry reference or a literal sequence number. |  | SequenceNumberProvider
| *trustAllCertificates* (consumer) | If we want to trust all certificates in case of overriding the endpoint | false | boolean
| *uriEndpointOverride* (consumer) | Set the overriding uri endpoint. This option needs to be used in combination with overrideEndpoint option |  | String
| *useDefaultCredentialsProvider* (consumer) | Set whether the DynamoDB Streams client should expect to load credentials through a default credentials provider or to expect static credentials to be passed in. | false | boolean
| *autowiredEnabled* (advanced) | Whether autowiring is enabled. This is used for automatic autowiring options (the option must be marked as autowired) by looking up in the registry to find if there is a single instance of matching type, which then gets configured on the component. This can be used for automatic configuring JDBC data sources, JMS connection factories, AWS Clients, etc. | true | boolean
| *accessKey* (security) | Amazon AWS Access Key |  | String
| *secretKey* (security) | Amazon AWS Secret Key |  | String
|===
// component options: END






// endpoint options: START
The AWS DynamoDB Streams endpoint is configured using URI syntax:

----
aws2-ddbstream:tableName
----

with the following path and query parameters:

=== Path Parameters (1 parameters):


[width="100%",cols="2,5,^1,2",options="header"]
|===
| Name | Description | Default | Type
| *tableName* | *Required* Name of the dynamodb table |  | String
|===


=== Query Parameters (33 parameters):


[width="100%",cols="2,5,^1,2",options="header"]
|===
| Name | Description | Default | Type
| *amazonDynamoDbStreamsClient* (consumer) | *Autowired* Amazon DynamoDB client to use for all requests for this endpoint |  | DynamoDbStreamsClient
| *bridgeErrorHandler* (consumer) | Allows for bridging the consumer to the Camel routing Error Handler, which mean any exceptions occurred while the consumer is trying to pickup incoming messages, or the likes, will now be processed as a message and handled by the routing Error Handler. By default the consumer will use the org.apache.camel.spi.ExceptionHandler to deal with exceptions, that will be logged at WARN or ERROR level and ignored. | false | boolean
| *iteratorType* (consumer) | Defines where in the DynaboDB stream to start getting records. Note that using TRIM_HORIZON can cause a significant delay before the stream has caught up to real-time. if {AT,AFTER}_SEQUENCE_NUMBER are used, then a sequenceNumberProvider MUST be supplied. There are 5 enums and the value can be one of: TRIM_HORIZON, LATEST, AT_SEQUENCE_NUMBER, AFTER_SEQUENCE_NUMBER, null | LATEST | ShardIteratorType
| *maxResultsPerRequest* (consumer) | Maximum number of records that will be fetched in each poll |  | int
| *overrideEndpoint* (consumer) | Set the need for overidding the endpoint. This option needs to be used in combination with uriEndpointOverride option | false | boolean
| *proxyHost* (consumer) | To define a proxy host when instantiating the DDBStreams client |  | String
| *proxyPort* (consumer) | To define a proxy port when instantiating the DDBStreams client |  | Integer
| *proxyProtocol* (consumer) | To define a proxy protocol when instantiating the DDBStreams client. There are 2 enums and the value can be one of: HTTP, HTTPS | HTTPS | Protocol
| *region* (consumer) | The region in which DDBStreams client needs to work |  | String
| *sendEmptyMessageWhenIdle* (consumer) | If the polling consumer did not poll any files, you can enable this option to send an empty message (no body) instead. | false | boolean
| *sequenceNumberProvider* (consumer) | Provider for the sequence number when using one of the two ShardIteratorType.{AT,AFTER}_SEQUENCE_NUMBER iterator types. Can be a registry reference or a literal sequence number. |  | SequenceNumberProvider
| *trustAllCertificates* (consumer) | If we want to trust all certificates in case of overriding the endpoint | false | boolean
| *uriEndpointOverride* (consumer) | Set the overriding uri endpoint. This option needs to be used in combination with overrideEndpoint option |  | String
| *useDefaultCredentialsProvider* (consumer) | Set whether the DynamoDB Streams client should expect to load credentials through a default credentials provider or to expect static credentials to be passed in. | false | boolean
| *exceptionHandler* (consumer) | To let the consumer use a custom ExceptionHandler. Notice if the option bridgeErrorHandler is enabled then this option is not in use. By default the consumer will deal with exceptions, that will be logged at WARN or ERROR level and ignored. |  | ExceptionHandler
| *exchangePattern* (consumer) | Sets the exchange pattern when the consumer creates an exchange. There are 3 enums and the value can be one of: InOnly, InOut, InOptionalOut |  | ExchangePattern
| *pollStrategy* (consumer) | A pluggable org.apache.camel.PollingConsumerPollingStrategy allowing you to provide your custom implementation to control error handling usually occurred during the poll operation before an Exchange have been created and being routed in Camel. |  | PollingConsumerPollStrategy
| *backoffErrorThreshold* (scheduler) | The number of subsequent error polls (failed due some error) that should happen before the backoffMultipler should kick-in. |  | int
| *backoffIdleThreshold* (scheduler) | The number of subsequent idle polls that should happen before the backoffMultipler should kick-in. |  | int
| *backoffMultiplier* (scheduler) | To let the scheduled polling consumer backoff if there has been a number of subsequent idles/errors in a row. The multiplier is then the number of polls that will be skipped before the next actual attempt is happening again. When this option is in use then backoffIdleThreshold and/or backoffErrorThreshold must also be configured. |  | int
| *delay* (scheduler) | Milliseconds before the next poll. | 500 | long
| *greedy* (scheduler) | If greedy is enabled, then the ScheduledPollConsumer will run immediately again, if the previous run polled 1 or more messages. | false | boolean
| *initialDelay* (scheduler) | Milliseconds before the first poll starts. | 1000 | long
| *repeatCount* (scheduler) | Specifies a maximum limit of number of fires. So if you set it to 1, the scheduler will only fire once. If you set it to 5, it will only fire five times. A value of zero or negative means fire forever. | 0 | long
| *runLoggingLevel* (scheduler) | The consumer logs a start/complete log line when it polls. This option allows you to configure the logging level for that. There are 6 enums and the value can be one of: TRACE, DEBUG, INFO, WARN, ERROR, OFF | TRACE | LoggingLevel
| *scheduledExecutorService* (scheduler) | Allows for configuring a custom/shared thread pool to use for the consumer. By default each consumer has its own single threaded thread pool. |  | ScheduledExecutorService
| *scheduler* (scheduler) | To use a cron scheduler from either camel-spring or camel-quartz component. Use value spring or quartz for built in scheduler | none | Object
| *schedulerProperties* (scheduler) | To configure additional properties when using a custom scheduler or any of the Quartz, Spring based scheduler. |  | Map
| *startScheduler* (scheduler) | Whether the scheduler should be auto started. | true | boolean
| *timeUnit* (scheduler) | Time unit for initialDelay and delay options. There are 7 enums and the value can be one of: NANOSECONDS, MICROSECONDS, MILLISECONDS, SECONDS, MINUTES, HOURS, DAYS | MILLISECONDS | TimeUnit
| *useFixedDelay* (scheduler) | Controls if fixed delay or fixed rate is used. See ScheduledExecutorService in JDK for details. | true | boolean
| *accessKey* (security) | Amazon AWS Access Key |  | String
| *secretKey* (security) | Amazon AWS Secret Key |  | String
|===
// endpoint options: END
// spring-boot-auto-configure options: START
// spring-boot-auto-configure options: END


Required DynamoDBStream component options

You have to provide the DynamoDbStreamsClient in the
Registry with proxies and relevant credentials
configured.

== Sequence Numbers

You can provide a literal string as the sequence number or provide a
bean in the registry. An example of using the bean would be to save your
current position in the change feed and restore it on Camel startup.

It is an error to provide a sequence number that is greater than the
largest sequence number in the describe-streams result, as this will
lead to the AWS call returning an HTTP 400.

== Usage

=== Static credentials vs Default Credential Provider

You have the possibility of avoiding the usage of explicit static credentials, by specifying the useDefaultCredentialsProvider option and set it to true.

 - Java system properties - aws.accessKeyId and aws.secretKey
 - Environment variables - AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY.
 - Web Identity Token from AWS STS.
 - The shared credentials and config files.
 - Amazon ECS container credentials - loaded from the Amazon ECS if the environment variable AWS_CONTAINER_CREDENTIALS_RELATIVE_URI is set.
 - Amazon EC2 Instance profile credentials. 

For more information about this you can look at https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/credentials.html[AWS credentials documentation]

== Coping with Downtime

=== AWS DynamoDB Streams outage of less than 24 hours

The consumer will resume from the last seen sequence number (as
implemented
for https://issues.apache.org/jira/browse/CAMEL-9515[CAMEL-9515]), so
you should receive a flood of events in quick succession, as long as the
outage did not also include DynamoDB itself.

=== AWS DynamoDB Streams outage of more than 24 hours

Given that AWS only retain 24 hours worth of changes, you will have
missed change events no matter what mitigations are in place.

=== Message Body

The Message body is istance of "software.amazon.awssdk.services.dynamodb.model.Record", for more information about it, have a look at the https://sdk.amazonaws.com/java/api/latest/software/amazon/awssdk/services/dynamodb/model/Record.html[related javadoc]

== Dependencies

Maven users will need to add the following dependency to their pom.xml.

*pom.xml*

[source,xml]
---------------------------------------
<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-aws2-ddb</artifactId>
    <version>${camel-version}</version>
</dependency>
---------------------------------------

where `$\{camel-version}` must be replaced by the actual version of Camel.

include::{page-component-version}@camel-spring-boot::page$aws2-ddb-starter.adoc[]
