Package com.cognite.client

Class Events

    • Field Detail

      • LOG

        protected static final org.slf4j.Logger LOG

    • Constructor Detail

      • Events

        public Events()

    • Method Detail

      • of

        public static Events of​(CogniteClient client)
        Constructs a new Events object using the provided client configuration.

        This method is intended for internal use--SDK clients should always use CogniteClient as the entry point to this class.

        Parameters:
        client - The CogniteClient to use for configuration settings.
        Returns:
        the events api object.

      • list

        public Iterator<List<Event>> list​(Request requestParameters)
                           throws Exception
        Returns all Event objects that matches the filters set in the Request.

        The results are paged through / iterated over via an Iterator--the entire results set is not buffered in memory, but streamed in "pages" from the Cognite api. If you need to buffer the entire results set, then you have to stream these results into your own data structure.

        The events are retrieved using multiple, parallel request streams towards the Cognite api. The number of parallel streams are set in the ClientConfig.

        Example:

         
      List<Event> listResults = new ArrayList<>();
      client.events()
              .list(Request.create()
                             .withFilterParameter("source", "source"))
              .forEachRemaining(listResults::addAll);
        API Reference - Filter all events
        Specified by:
        list in interface ListSource<Event>
        Parameters:
        requestParameters - the filters to use for retrieving the events.
        Returns:
        an Iterator to page through the results set.
        Throws:
        Exception
        See Also:
        list(Request,String...), CogniteClient, CogniteClient.events()

      • list

        public Iterator<List<Event>> list​(Request requestParameters,
                                  String... partitions)
                           throws Exception
        Returns all Event objects that matches the filters set in the Request for the specified partitions. This is method is intended for advanced use cases where you need direct control over the individual partitions. For example, when using the SDK in a distributed computing environment.

        The results are paged through / iterated over via an Iterator--the entire results set is not buffered in memory, but streamed in "pages" from the Cognite api. If you need to buffer the entire results set, then you have to stream these results into your own data structure.

        Example:

         
      List<Event> listResults = new ArrayList<>();
      client.events()
              .list(Request.create()
                             .withFilterParameter("source", "source"),
                                  "1/8","2/8","3/8","4/8","5/8","6/8","7/8","8/8")
              .forEachRemaining(listResults::addAll);
        API Reference - Filter all events
        Parameters:
        requestParameters - the filters to use for retrieving the events.
        partitions - the partitions to include.
        Returns:
        an Iterator to page through the results set.
        Throws:
        Exception
        See Also:
        listJson(ResourceType,Request,String...), CogniteClient, CogniteClient.events()

      • stream

        public Publisher<Event> stream()
        Returns a Publisher that can stream Event from Cognite Data Fusion. When an Event is created or updated, it will be captured by the publisher and emitted to the registered consumer.

        Example:

         
      List<Event> eventList = new CopyOnWriteArrayList<>();
      Publisher<Event> publisher = client.events().stream()
                     .withRequest(Request.create()
                             .withFilterMetadataParameter("source", "source"))
                     .withStartTime(Instant.now())
                     .withEndTime(Instant.now().plusSeconds(25))
                     .withPollingInterval(Duration.ofSeconds(2))
                     .withPollingOffset(Duration.ofSeconds(15L))
                     .withConsumer(batch -> {
                         eventList.addAll(batch);
                     });
      Future<Boolean> streamer = publisher.start();
      Boolean result = streamer.get();
        Returns:
        The publisher producing the stream of events. Call start() to start the stream.
        See Also:
        CogniteClient, CogniteClient.events(), CopyOnWriteArrayList

      • uploadQueue

        public UploadQueue<Event,​Event> uploadQueue()
        Returns an upload queue. The upload queue helps improve performance by batching items together before uploading them to Cognite Data Fusion.
        Returns:
        The upload queue.

      • delete

        public List<Item> delete​(List<Item> events)
                  throws Exception
        Deletes a set of Events.

        The events to delete are identified via their externalId / id by submitting a list of Item.

        Example:

         
     List<Item> events = List.of(Item.newBuilder().setExternalId("1").build());
     List<Item> deletedItemsResults = client.events().delete(events);
        API Reference - Delete multiple events
        Parameters:
        events - a list of Item representing the events (externalId / id) to be deleted
        Returns:
        The deleted events via Item
        Throws:
        Exception
        See Also:
        ApiBase.DeleteItems.deleteItems(List), CogniteClient, CogniteClient.events()

      • buildPartitionsList

        protected List<String> buildPartitionsList​(int noPartitions)
        Builds an array of partition specifications for parallel retrieval from the Cognite api. This specification is used as a parameter together with the filter / list endpoints. The number of partitions indicate the number of parallel read streams. Employ one partition specification per read stream.

        Example:

         
      List<String> partitions = buildPartitionsList(getClient().getClientConfig().getNoListPartitions());
        Parameters:
        noPartitions - The total number of partitions
        Returns:
        a List of partition specifications

      • listJson

        protected Iterator<List<String>> listJson​(ResourceType resourceType,
                                          Request requestParameters,
                                          String... partitions)
                                   throws Exception
        Will return the results from a list / filter api endpoint. For example, the filter assets endpoint. The results are paged through / iterated over via an Iterator--the entire results set is not buffered in memory, but streamed in "pages" from the Cognite api. If you need to buffer the entire results set, then you have to stream these results into your own data structure. This method support parallel retrieval via a set of partition specifications. The specified partitions will be collected and merged together before being returned via the Iterator.

        Example:

         
      Iterator<List<String>> result = listJson(resourceType, requestParameters, partitions);
        Parameters:
        resourceType - The resource type to query / filter / list. Ex. event, asset, time series.
        requestParameters - The query / filter specification. Follows the Cognite api request parameters.
        partitions - An optional set of partitions to read via.
        Returns:
        an Iterator over the results set.
        Throws:
        Exception
        See Also:
        listJson(ResourceType,Request,String,String...)

      • listJson

        protected Iterator<List<String>> listJson​(ResourceType resourceType,
                                          Request requestParameters,
                                          String partitionKey,
                                          String... partitions)
                                   throws Exception
        Will return the results from a list / filter api endpoint. For example, the filter assets endpoint. The results are paged through / iterated over via an Iterator--the entire results set is not buffered in memory, but streamed in "pages" from the Cognite api. If you need to buffer the entire results set, then you have to stream these results into your own data structure. This method support parallel retrieval via a set of partition specifications. The specified partitions will be collected and merged together before being returned via the Iterator.

        Example:

         
      Iterator<List<String>> result = listJson(resourceType, requestParameters, partitionKey, partitions);
        Parameters:
        resourceType - The resource type to query / filter / list. Ex. event, asset, time series.
        requestParameters - The query / filter specification. Follows the Cognite api request parameters.
        partitionKey - The key to use for the partitions in the read request. For example partition or cursor.
        partitions - An optional set of partitions to read via.
        Returns:
        an Iterator over the results set.
        Throws:
        Exception

      • retrieveJson

        protected List<String> retrieveJson​(ResourceType resourceType,
                                    Collection<Item> items)
                             throws Exception
        Retrieve items by id. Will ignore unknown ids by default.

        Example:

         
      Collection<Item> items = //Collection of items with ids;
      List<String> result = retrieveJson(resourceType, items);
        Parameters:
        resourceType - The item resource type (Event, Asset, etc.) to retrieve.
        items - The item(s) externalId / id to retrieve.
        Returns:
        The items in Json representation.
        Throws:
        Exception
        See Also:
        retrieveJson(ResourceType,Collection,Map)

      • retrieveJson

        protected List<String> retrieveJson​(ResourceType resourceType,
                                    Collection<Item> items,
                                    Map<String,​Object> parameters)
                             throws Exception
        Retrieve items by id. This version allows you to explicitly set additional parameters for the retrieve request. For example: <"ignoreUnknownIds", true> and <"fetchResources", true>.

        Example:

         
      Collection<Item> items = //Collection of items with ids;
      Map<String, Object> parameters = //Parameters;
      List<String> result = retrieveJson(resourceType, items, parameters);
        Parameters:
        resourceType - The item resource type (Event, Asset, etc.) to retrieve.
        items - The item(s) externalId / id to retrieve.
        parameters - Additional parameters for the request. For example <"ignoreUnknownIds", true>
        Returns:
        The items in Json representation.
        Throws:
        Exception

      • aggregate

        protected Aggregate aggregate​(ResourceType resourceType,
                              Request requestParameters)
                       throws Exception
        Performs an item aggregation request to Cognite Data Fusion. The default aggregation is a total item count based on the (optional) filters in the request. Some resource types, for example Event, supports multiple types of aggregation.

        Example:

         
      Aggregate aggregateResult = aggregate(resourceType,requestParameters);
        Parameters:
        resourceType - The resource type to perform aggregation of.
        requestParameters - The request containing filters.
        Returns:
        The aggregation result.
        Throws:
        Exception
        See Also:
        Cognite API v1 specification

      • addAuthInfo

        protected Request addAuthInfo​(Request request)
                       throws Exception
        Adds the required authentication information into the request object. If the request object already have complete auth info nothing will be added. The following authentication schemes are supported: 1) API key. When using an api key, this service will look up the corresponding project/tenant to issue requests to.

        Example:

         
      Request requestParams = addAuthInfo(request);
        Parameters:
        request - The request to enrich with auth information.
        Returns:
        The request parameters with auth info added to it.
        Throws:
        Exception

      • parseItems

        protected List<Item> parseItems​(List<String> input)
                         throws Exception
        Parses a list of item object in json representation to typed objects.

        Example:

         
      List<String> input = //List of json;
      List<Item> resultList = parseItems(input);
        Parameters:
        input - the item list in Json string representation
        Returns:
        the parsed item objects
        Throws:
        Exception

      • toRequestItems

        protected List<Map<String,​Object>> toRequestItems​(Collection<Item> itemList)
        Converts a list of Item to a request object structure (that can later be parsed to Json).

        Example:

         
      Collection<Item> itemList = //Collection of items;
      List<Map<String, Object>> result = toRequestItems(itemList);
        Parameters:
        itemList - The items to parse.
        Returns:
        The items in request item object form.

      • deDuplicate

        protected List<Item> deDuplicate​(Collection<Item> itemList)
        De-duplicates a collection of Item.

        Example:

         
      Collection<Item> itemList = //Collection of items;
      List<Item> result = deDuplicate(itemList);
        Parameters:
        itemList -
        Returns:

      • itemsHaveId

        protected boolean itemsHaveId​(Collection<Item> items)
        Returns true if all items contain either an externalId or id.

        Example:

         
      Collection<Item> items = //Collection of items;
      boolean result = itemsHaveId(items);
        Parameters:
        items -
        Returns:

      • mapItemToId

        protected Map<String,​Item> mapItemToId​(Collection<Item> items)
        Maps all items to their externalId (primary) or id (secondary). If the id function does not return any identity, the item will be mapped to the empty string. Via the identity mapping, this function will also perform deduplication of the input items.

        Example:

         
      Collection<Item> items = //Collection of items;
      Map<String, Item> result = mapItemToId(items);
        Parameters:
        items - the items to map to externalId / id.
        Returns:
        the Map with all items mapped to externalId / id.

      • parseString

        protected String parseString​(String itemJson,
                             String fieldName)
        Try parsing the specified Json path as a String.

        Example:

         
      String json = //String of json object
      String result = parseString(json, "name");
        Parameters:
        itemJson - The Json string
        fieldName - The Json path to parse
        Returns:
        The Json path as a String.

      • parseName

        protected String parseName​(String json)
        Returns the name attribute value from a json input.

        Example:

         
      String json = //String of json object
      String result = parseName(json);
        Parameters:
        json - the json to parse
        Returns:
        The name value