Package org.camunda.bpm.client

Interface ExternalTaskClientBuilder

All Known Implementing Classes:
ExternalTaskClientBuilderImpl
public interface ExternalTaskClientBuilder

A fluent builder to configure the Camunda client

Author:
Tassilo Weidner

  • Method Details

    • baseUrl

      ExternalTaskClientBuilder baseUrl(String baseUrl)
      Base url of the Camunda BPM Platform REST API. This information is mandatory.
      Parameters:
      baseUrl - of the Camunda BPM Platform REST API
      Returns:
      the builder

    • workerId

      ExternalTaskClientBuilder workerId(String workerId)
      A custom worker id the Workflow Engine is aware of. This information is optional. Note: make sure to choose a unique worker id

      If not given or null, a worker id is generated automatically which consists of the hostname as well as a random and unique 128 bit string (UUID).

      Parameters:
      workerId - the Workflow Engine is aware of
      Returns:
      the builder

    • addInterceptor

      ExternalTaskClientBuilder addInterceptor(ClientRequestInterceptor interceptor)
      Adds an interceptor to change a request before it is sent to the http server. This information is optional.
      Parameters:
      interceptor - which changes the request
      Returns:
      the builder

    • maxTasks

      ExternalTaskClientBuilder maxTasks(int maxTasks)
      Specifies the maximum amount of tasks that can be fetched within one request. This information is optional. Default is 10.
      Parameters:
      maxTasks - which are supposed to be fetched within one request
      Returns:
      the builder

    • usePriority

      ExternalTaskClientBuilder usePriority(boolean usePriority)
      Specifies whether tasks should be fetched based on their priority or arbitrarily. This information is optional. Default is true.
      Parameters:
      usePriority - when fetching and locking tasks
      Returns:
      the builder

    • useCreateTime

      ExternalTaskClientBuilder useCreateTime(boolean useCreateTime)
      Specifies whether tasks should be fetched based on their create time. If useCreateTime is passed using true, the tasks are going to be fetched in Descending order, otherwise false will not consider create time.
      Parameters:
      useCreateTime - the flag to control whether create time should be considered as a desc sorting criterion (newer tasks will be returned first)
      Returns:
      the builder

    • orderByCreateTime

      ExternalTaskClientBuilder orderByCreateTime()
      Fluent API method for configuring createTime as a sorting criterion for fetching of the tasks. Can be used in conjunction with asc or desc methods to configure the respective order for createTime. The method needs to be called first before specifying the order.
      Returns:
      the builder

    • asc

      ExternalTaskClientBuilder asc()
      Fluent API method to configure Ascending order on the associated field. Used in conjunction with an orderBy method such as orderByCreateTime.
      Returns:
      the builder

    • desc

      ExternalTaskClientBuilder desc()
      Fluent API method to configure Descending order on the associated field. Used in conjunction with an orderBy method such as orderByCreateTime.
      Returns:
      the builder

    • defaultSerializationFormat

      ExternalTaskClientBuilder defaultSerializationFormat(String defaultSerializationFormat)
      Specifies the serialization format that is used to serialize objects when no specific format is requested. This option defaults to application/json.
      Parameters:
      defaultSerializationFormat - serialization format to be used
      Returns:
      the builder

    • dateFormat

      ExternalTaskClientBuilder dateFormat(String dateFormat)
      Specifies the date format to de-/serialize date variables.
      Parameters:
      dateFormat - date format to be used
      Returns:
      the builder

    • asyncResponseTimeout

      ExternalTaskClientBuilder asyncResponseTimeout(long asyncResponseTimeout)
      Asynchronous response (long polling) is enabled if a timeout is given. Specifies the maximum waiting time for the response of fetched and locked external tasks. The response is performed immediately, if external tasks are available in the moment of the request. This information is optional. Unless a timeout is given, fetch and lock responses are synchronous.
      Parameters:
      asyncResponseTimeout - of fetched and locked external tasks in milliseconds
      Returns:
      the builder

    • lockDuration

      ExternalTaskClientBuilder lockDuration(long lockDuration)
      Parameters:
      lockDuration -
      • in milliseconds to lock the external tasks
      • must be greater than zero
      • the default lock duration is 20 seconds (20,000 milliseconds)
      • is overridden by the lock duration configured on a topic subscription
      Returns:
      the builder

    • disableAutoFetching

      ExternalTaskClientBuilder disableAutoFetching()
      Disables immediate fetching for external tasks after calling build() to bootstrap the client. To start fetching ExternalTaskClient.start() must be called.
      Returns:
      the builder

    • backoffStrategy

      ExternalTaskClientBuilder backoffStrategy(BackoffStrategy backoffStrategy)
      Adds a custom strategy to the client for defining the org.camunda.bpm.client.backoff between two requests. This information is optional. By default ExponentialBackoffStrategy is applied.
      Parameters:
      backoffStrategy - which realizes a custom org.camunda.bpm.client.backoff strategy
      Returns:
      the builder

    • disableBackoffStrategy

      ExternalTaskClientBuilder disableBackoffStrategy()
      Disables the client-side backoff strategy. On invocation, the configuration option backoffStrategy(org.camunda.bpm.client.backoff.BackoffStrategy) is ignored.

      NOTE: Please bear in mind that disabling the client-side backoff can lead to heavy load situations on engine side. To avoid this, please specify an appropriate asyncResponseTimeout(long).

      Returns:
      the builder

    • customizeHttpClient

      ExternalTaskClientBuilder customizeHttpClient(Consumer<org.apache.hc.client5.http.impl.classic.HttpClientBuilder> httpClientConsumer)
      Exposes the internal Apache HttpClientBuilder for custom client configurations.

      Interceptors added via addInterceptor(ClientRequestInterceptor) are added as last in the build() method.

      Parameters:
      httpClientConsumer - the parameter that accepts the HttpClientBuilder
      Returns:
      the builder

    • build

      ExternalTaskClient build()
      Bootstraps the Camunda client
      Returns:
      the builder
      Throws:
      ExternalTaskClientException -
      • if base url is null or string is empty
      • if hostname cannot be retrieved
      • if maximum amount of tasks is not greater than zero
      • if maximum asynchronous response timeout is not greater than zero
      • if lock duration is not greater than zero