Package com.cognite.client

Class RawRows

    • Field Detail

      • LOG

        protected static final org.slf4j.Logger LOG

    • Constructor Detail

      • RawRows

        public RawRows()

    • Method Detail

      • of

        public static RawRows of​(CogniteClient client)
        Constructs a new RawRows 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 assets api object.

      • list

        public Iterator<List<RawRow>> list​(String dbName,
                                   String tableName,
                                   Request requestParameters,
                                   String... cursors)
                            throws Exception
        Returns a set of rows from a table. The rows are returned 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:

         
     int noCursors = getClient().getClientConfig().getNoListPartitions();
     List<String> cursors = retrieveCursors(dbName, tableName, noCursors, requestParameters);
     List<RawRow> listResults = new ArrayList<>();
     client.raw()
           .rows()
           .list("dbName", "tableName",
                      Request.create().withRootParameter("columns", List.of("columnName")),
                      cursors.toArray(new String[cursors.size()]))
           .forEachRemaining(listResults::addAll);
        API Reference - Retrieve rows from a table
        Parameters:
        dbName - the database to list rows from.
        tableName - the table to list rows from.
        requestParameters - the column and filter specification for the rows.
        Returns:
        an Iterator to page through the rows.
        Throws:
        Exception
        See Also:
        ClientConfig.getNoListPartitions(), retrieveCursors(String, String, int, Request), list(String, String, Request, String...), CogniteClient, CogniteClient.raw(), Raw.rows()

      • stream

        public RawPublisher stream​(String dbName,
                           String tableName)
        Returns a RawPublisher that can stream RawRow from a raw table.

        Example:

         
     AtomicInteger receiveRowsCount = new AtomicInteger(0);
     List<RawRow> rowList = new CopyOnWriteArrayList<>();

     RawPublisher publisher = client.raw().rows().stream("dbName", "tableName")
             .withStartTime(Instant.now())
             .withEndTime(Instant.now().plusSeconds(20))
             .withPollingInterval(Duration.ofSeconds(2))
             .withConsumer(batch -> {
                  receiveRowsCount.addAndGet(batch.size());
                  rowList.addAll(batch);
             });

     Future<Boolean> streamer = publisher.start();
        Parameters:
        dbName - The database to read rows from.
        tableName - The table to read rows from.
        Returns:
        The publisher producing the stream of objects. Call start() to start the stream.
        See Also:
        AtomicInteger, CopyOnWriteArrayList, RawPublisher, CogniteClient, CogniteClient.raw(), Raw.rows()

      • retrieveCursors

        public List<String> retrieveCursors​(String dbName,
                                    String tableName,
                                    Request requestParameters)
                             throws Exception
        Retrieves cursors for parallel retrieval of rows from Raw. This is intended for advanced use cases where you need granular control of the parallel retrieval from Raw--for example in distributed processing frameworks. Most scenarios should just use list directly as that will automatically handle parallelization for you.

        Example:

         
     List<RawRow> rowsRetrieved =
         client.raw()
         .rows()
         .retrieveCursors("dbName", "tableName", Request.create());
        API Reference - Retrieve cursors for parallel reads
        Parameters:
        dbName - The database to retrieve row cursors from.
        tableName - The table to retrieve row cursors from.
        requestParameters - Hosts query parameters like max and min time stamps and number of cursors to request.
        Returns:
        A list of cursors.
        Throws:
        Exception
        See Also:
        retrieveCursors(String, String, int, Request), CogniteClient, CogniteClient.raw(), Raw.rows()

      • retrieveCursors

        public List<String> retrieveCursors​(String dbName,
                                    String tableName,
                                    int noCursors,
                                    Request requestParameters)
                             throws Exception
        Retrieves cursors for parallel retrieval of rows from Raw. This is intended for advanced use cases where you need granular control of the parallel retrieval from Raw--for example in distributed processing frameworks. Most scenarios should just use list directly as that will automatically handle parallelization for you.

        Example:

         
     int noCursors = getClient().getClientConfig().getNoListPartitions();
     List<RawRow> rowsRetrieved =
         client.raw()
         .rows()
         .retrieveCursors("dbName", "tableName", noCursors, Request.create());
        API Reference - Retrieve cursors for parallel reads
        Parameters:
        dbName - The database to retrieve row cursors from.
        tableName - The table to retrieve row cursors from.
        noCursors - The number of cursors.
        requestParameters - Hosts query parameters like max and min time stamps and number of cursors to request.
        Returns:
        A list of cursors.
        Throws:
        Exception
        See Also:
        ClientConfig.getNoListPartitions(), CogniteClient, CogniteClient.raw(), Raw.rows()

      • uploadQueue

        public UploadQueue<RawRow,​RawRow> 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.

      • 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