cognitedata / cdp-spark-datasource   3.15.1105

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Spark data source for Cognite Data Fusion

Scala versions: 2.13 2.12 2.11

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Spark Data Source

The Cognite Spark Data Source lets you use Spark to read and write data from and to Cognite Data Fusion (CDF).

Reads and writes are done in parallel using asynchronous calls.

The instructions below explain how to read from, and write to, the different resource types in CDF.

In this article

Quickstart

Add the Spark data source to your cluster. We recommend using the latest version. If using spark-submit or spark-shell or pyspark, you can use --packages com.cognite.spark.datasource:cdf-spark-datasource_2.12:<latest-release> (change to 2.13 if you're using Scala 2.13). If you're using Databricks, add the Maven coordinate com.cognite.spark.datasource:cdf-spark-datasource_2.12:<latest-release> as a library to your cluster.

You can also use spark.jars.packages to include this data source using the same coordinate. See the official documentation for more information. Note that you should not use --jars or spark.jars, as those options will not download and add the dependencies of our Spark data source.

Then, try it out!

df = spark.read.format("cognite.spark.v1")
  .option("type", "assets")
  # add .options to configure access like OIDC tokens options
  .load()
df.count

Read and write to CDF

The Cognite Spark Data Source lets you read data from and write data to these resource types: assets, time series, data points, events, and RAW tables. For files and 3D models, you can read metadata .

Common options

Some options are common to all resource types. To set the options, use spark.read.format("cognite.spark.v1").option("nameOfOption", "value").

The common options are:

Option Description Required
bearerToken The CDF token for authorization. Yes, if you don't specify options for the native tokens.
project The CDF project.
type The Cognite Data Fusion resource type. See below for more resource type examples. Yes
maxRetries The maximum number of retries to be made when a request fails. Default: 10
maxRetryDelay The maximum number of seconds to wait between retrying requests. Default: 30
limitPerPartition The number of items to fetch for this resource type to create the DataFrame. Note that this is different from the SQL SELECT * FROM ... LIMIT 1000 limit. This option specifies the limit for items to fetch from CDF per partition, before filtering and other transformations are applied to limit the number of results. Not supported by data points.
batchSize The maximum number of items to read/write per API call.
baseUrl Address of the CDF API. For example might be changed to https://greenfield.cognitedata.com. By default it is set to https://api.cognitedata.com
collectMetrics true or false - if Spark metrics should be collected about number of reads, inserts, updates and deletes
metricsPrefix Common prefix for all collected metrics. Might be useful when working with multiple connections.
partitions Number of CDF partitions to use. By default it's 200.
parallelismPerPartition How many parallel request should run for one Spark partition. Number of Spark partitions = partitions / parallelismPerPartition
applicationName Identifies the application making requests by including a X-CDP-App header. Defaults to com.cognite.spark.datasource-(version)
clientTag If set, will be included as a X-CDP-ClientTag header in requests. This is typically used to group sets of requests as belonging to some definition of a job or workload for debugging.

To autenticate using OIDC tokens set all of these options:

Option Description Required
tokenUri Token uri to request a token from. (Example: https://login.microsoftonline.com/<Directory (tenant) ID>/oauth2/v2.0/token) Yes
clientId Application (client) ID associated with the target CDF project. Yes
clientSecret Client secret for the application. Yes
project The CDF project. Yes
scopes The scopes needed for the user. Required for AAD setup. No
baseUrl Address of the CDF API. For example might be changed to https://greenfield.cognitedata.com. By default it is set to https://api.cognitedata.com Yes
audience The audience needed for token retrieval, supported for the custom Aize and AKSO OAuth2 setup. No

Read data

To read from CDF resource types, you need to specify: a bearertoken and the resource type you want to read from. To read from a table you also need to specify the database and table names.

Filter pushdown

For some fields, filters are pushed down to the API. For example, if you read events with a filter on asset IDs, only the IDs that satisfy the filter are read from CDF, as opposed to reading all events and then applying the filter. This happens automatically, but note that filters are only pushed down when Spark reads data from CDF, and not when working on a DataFrame that is already in memory.

externalId and id always support this filter, for most resources it's also possible to filter by externalId prefix. For example query where externalId LIKE 'my-id-prefix-%' will only fetch items with the matching id. Note that the filter only works on prefix, not any substring, so querying where externalId LIKE '%-something-%' will download all items from CDF.

Generally, filtering works on anything that CDF API can filter on. If it does not work for something you'd expect to work, feel free to report it to Cognite. However, due to limitations in Spark we cannot filter on metadata field. See Schema section for more details on which filters are supported.

  • equality means that column = 'x', column IN ('x', 'y') and similar are supported
  • comparison means that column <= 10, column > 10 and similar are supported

In practice, it's often useful to filter on datasetId. Usually, one query only needs items from a single dataset, so it's an easy way to improve run-time.

Note that filter pushdown works even with more complex predicates with AND and OR operators.

Write data

You can write to CDF with:

  • insertInto - checks that all fields are present and in the correct order. Can be more convenient when you're working with Spark SQL tables.

  • save - gives you control over how to handle potential collisions with existing data, and allows you to update a subset of fields in a row.

.insertInto()

To write to a resource using the insert into pattern, you'll need to register a DataFrame that was read from the resource, as a temporary view. You also need write access to the project and resources. In the examples below, also add access options.

Your schema must match that of the target exactly. To ensure this, copy the schema from the DataFrame you read into with sourceDf.select(destinationDf.columns.map(col):_*). See the time series example below.

.insertInto() does upserts (updates existing rows and inserts new rows) for events, assets, and time series. .insertInto() upserts use externalId (ignoring id), attempting to create a row with externalId if set, and if a row with the given externalId already exists it will be updated.

Data points also have upsert behavior, but based on the timestamp.

For RAW tables, .insertInto() does inserts and throws an error if one or more rows already exist. For files, insertInto() only supports updating existing files.

.save()

We currently support writing with .save() for assets, events, and time series. You can also use .option("onconflict", value) to specify the desired behavior when rows in your Dataframe are present in CDF.

The valid options for onconflict are:

  • abort - tries to insert all rows in the Dataframe. Throws an error if the resource item already exists, and no more rows will be written.

  • update - looks for all rows in the Dataframe in CDF and tries to update them. If one or more rows do not exist, no more rows are updated and an error is thrown. Supports partial updates.

  • upsert - updates rows that already exist, and inserts new rows. In this mode inserted rows with id set will always attempt to update the target row with such an id. If id is null, or not present, and externalId is not null, it will attempt to create a row with the given externalId. If such a row already exists, that row will be updated to the values present in the row being inserted.

Multiple rows with the same id and externalId are allowed for upserts, but the order in which they are applied is undefined and we currently only guarantee that at least one upsert will be made for each externalId, and at least one update will be made for each id set.

This is based on the assumption that upserts for the same id or externalId will have the same values. If you have a use case where this is not the case, please let us know.

Handling NULLs and empty fields

By default, the Spark Datasource ignores NULLs when updating: nothing is written to CDF when there is a NULL in the field. This can be controlled by setting the ignoreNullFields option which defaults to "true" when using .save() writes. This is usually useful for ignoring the columns which are irrelevant for a task, however it makes it impossible to null a field in CDF. When the ignoreNullFields option is set to false, NULLs are written to CDF (when possible). Fields which are not specified are still ignored. See an example of using .save() under Events below.

Delete data

We currently support deleting with .save() for assets, events and time series.

You need to specify the resource type, and then specify delete as the onconflict option like this: .option("onconflict", "delete").

See an example for using .save() to delete under Time Series below.

Assets and events will ignore existing ids on deletes. If you prefer to abort the job when attempting to delete an unknown id, use .option("ignoreUnknownIds", "false") for those resources types.

Expected schema for delete of Time series, Assets, Events or Files is:

Column name Type Nullable
id long No

Expected schema for delete of Datapoints or String Datapoints is:

Column name Type Nullable
id long Yes
externalId string Yes
inclusiveBegin timestamp Yes
exclusiveBegin timestamp Yes
inclusiveEnd timestamp Yes
exclusiveEnd timestamp Yes

One of id & externalId, inclusiveBegin & exclusiveBegin and inclusiveEnd & exclusiveEnd must be specified. Data points are deleted by a range and both bound must be specified. To delete a single data point, set inclusiveBegin and inclusiveEnd to the same value. To delete a range between two points, set exclusiveBegin to the first point and exclusiveEnd to the second one; this will not delete the boundaries, but everything between them.

Asset hierarchy builder (beta)

Note: The asset hierarchy builder is currently in beta, and has not been sufficiently tested to be used on production data.

The .option("type", "assethierarchy") lets you write new asset hierarchies, or update existing ones, using the Spark Data Source. The asset hierarchy builder can ingest entire hierarchies of nodes connected through the externalId/parentExternalId relationship. If input contains an update to data that already exists, i.e there's a match on externalId and there's a change to one of the other fields, the asset will be updated. There's also an option to delete assets from CDF that are not referenced in the input data.

Requirements

  • Root assets are denoted by setting their parentExternalId to the empty string "".
  • The input data must not have loops, to ensure all asset hierarchies are fully connected.
  • externalId can not be the empty string "".

Options

Option Default Description
deleteMissingAssets false Whether or not you would like assets under the root to be deleted if they're not present in the input data.
subtrees ingest Controls what should happen with subtrees without a root node in the input data. ingest says they will be processed and loaded into CDF, ignore will ignore all of them and error will stop the execution and raise an error (nothing will be ingested).
batchSize 1000 The number of assets to write per API call.

Setup for Python

You may want to set up a Jupyter notebook with pySpark running.

  • Download spark version 2.4.5 here

  • Follow the instructions given here, except that your Spark version will be 2.4.5.

  • Start your Jupyter notebook with the following command (instead of pyspark as in the link above):

pyspark --packages com.cognite.spark.datasource:cdf-spark-datasource_2.11:1.2.18

Example (Scala)

val assetHierarchySchema = Seq("externalId", "parentExternalId", "source", "description", "name", "metadata")

// Manually create some assets that satisfy the requirements of the asset hierarchy builder
val assetHierarchy = Seq(
  ("root_asset", "", "manual_input", "root_asset", Some("This is the root asset"), Map("asset_depth" -> "0")),
  ("first_child", "root_asset", "manual_input", "first_child", Some("This is the first_child"), Map("asset_depth" -> "1")),
  ("second_child", "root_asset", "manual_input", "second_child", Some("This is the second_child"), Map("asset_depth" -> "1")),
  ("grandchild", "first_child", "manual_input", "grandchild", Some("This is the child of first_child"), Map("asset_depth" -> "2"))
)

val assetHierarchyDataFrame = spark
  .sparkContext
  .parallelize(assetHierarchy)
  .toDF(assetHierarchySchema:_*)

// Validate that the schema is as expected
assetHierarchyDataFrame.printSchema()

// Insert the assets with the asset hierarchy builder
assetHierarchyDataFrame.write
  .format("cognite.spark.v1")
  .option("type", "assethierarchy")
  .save()

// Have a look at your new asset hierarchy
spark.read
  .format("cognite.spark.v1")
  .option("type", "assets")
  .load()
  .where("source = 'manual_input'")
  .show()

// Delete everything but the root using the deleteMissingAssets flag
spark
  .sparkContext
  .parallelize(Seq(Seq("root_asset", "", "manual_input", "root_asset", Some("This is the root asset"), None)))
  .toDF(assetHierarchySchema)
  .format("cognite.spark.v1")
  .option("type", "assethierarchy")
  .option("deleteMissingAssets", "true")
  .save()

Example (Python)

assetHierarchySchema = ["externalId", "parentExternalId", "source", "description", "name", "metadata"]

# Manually create some assets that satisfy the requirements of the asset hierarchy builder
assetHierarchy = [
  ["root_asset", "", "manual_input", "root_asset", "This is the root asset", {"asset_depth" : "0"}],
  ["first_child", "root_asset", "manual_input", "first_child", "This is the first_child", {"asset_depth" : "1"}],
  ["second_child", "root_asset", "manual_input", "second_child", "This is the second_child", {"asset_depth" : "1"}],
  ["grandchild", "first_child", "manual_input", "grandchild", "This is the child of first_child", {"asset_depth" : "2"}]
]

assetHierarchyDataFrame = spark.sparkContext.parallelize(assetHierarchy).toDF(assetHierarchySchema)

# Validate that the schema is as expected
assetHierarchyDataFrame.printSchema()

# Insert the assets with the asset hierarchy builder
assetHierarchyDataFrame.write \
    .format("cognite.spark.v1") \
    .option("type", "assethierarchy") \
    .save()

# Have a look at your new asset hierarchy
spark.read \
  .format("cognite.spark.v1") \
  .option("type", "assets") \
  .load() \
  .where("source = 'manual_input'") \
  .show()

# Delete everything but the root using the deleteMissingAssets flag
spark \
    .sparkContext \
    .parallelize([["root_asset", "", "manual_input", "root_asset", "This is the root asset", {"":""}]]) \
    .toDF(assetHierarchySchema) \
    .write \
    .format("cognite.spark.v1") \
    .option("type", "assethierarchy") \
    .option("deleteMissingAssets", "true") \
    .save()

Schemas

Spark DataFrames have schemas, with typing and names for columns. When writing to a resource in CDF using the insertInto-pattern you have to match the schema exactly (see .insertInto() for a tip about this).

The schemas mirror the CDF API as closely as possible.

Assets schema

Column name Type Nullable Filter pushdown ?
externalId string Yes equality, prefix (LIKE 'xyz%')
name string No equality
parentId long Yes -
description string Yes -
metadata map(string, string) Yes -
source long Yes equality
id long No equality
createdTime timestamp No comparison
lastUpdatedTime timestamp No comparison
rootId long Yes -
aggregates map(string, long) Yes -
dataSetId long Yes equality

Events schema

Column name Type Nullable Filter pushdown ?
id long No equality
startTime timestamp Yes comparison, equality
endTime timestamp Yes comparison, equality
description string Yes -
type string Yes equality
subtype string Yes equality
metadata map(string, string) Yes -
assetIds array(long) Yes equality
source string Yes equality
externalId string Yes equality, prefix (LIKE 'xyz%')
createdTime timestamp No comparison
lastUpdatedTime timestamp No comparison
dataSetId long Yes equality

Files schema

Column name Type Nullable Filter pushdown ?
id long No equality
name string No equality
source long Yes equality
externalId string Yes equality, prefix (LIKE 'xyz%')
mimeType string Yes equality
metadata map(string, string) Yes -
assetIds array(long) Yes equality
uploaded boolean No equality
uploadedTime timestamp Yes comparison
createdTime timestamp No comparison
lastUpdatedTime timestamp No comparison
sourceCreatedTime timestamp Yes comparison
sourceModifiedTime timestamp Yes comparison
securityCategories array(long) Yes -
uploadUrl string Yes -
dataSetId long Yes equality

Data points schema

Column name Type Nullable Filter pushdown ?
id long Yes equality
externalId string Yes equality
timestamp timestamp No comparison, equality
value double No -
aggregation string Yes equality
granularity string Yes equality

String data points schema

Column name Type Nullable Filter pushdown ?
id long Yes equality
externalId string Yes equality
timestamp timestamp No comparison, equality
value string No -

Time series schema

Column name Type Nullable Filter pushdown ?
name string Yes equality
isString boolean No equality
metadata map(string, string) Yes -
unit string Yes equality
assetId long Yes equality
isStep boolean No equality
description string Yes -
securityCategories array(long) Yes -
id long No equality
externalId string Yes equality, prefix (LIKE 'xyz%')
createdTime timestamp No comparison
lastUpdatedTime timestamp No comparison
dataSetId long Yes equality

Asset Hierarchy schema

Column name Type Nullable
externalId string No
parentExternalId string No
source string Yes
name string No
description string Yes
metadata map(string, string) Yes
dataSetId long Yes

Sequences schema

Column name Type Nullable
externalId string Yes
name string Yes
description string Yes
assetId long Yes
metadata map(string, string) Yes
dataSetId long Yes
columns array(SequenceColumn) No

The columns field is an array of SequenceColumns, which are rows with the following fields:

Column name Type Nullable
name string Yes
externalId string No
description string Yes
valueType string No
metadata map(string, string) Yes

Sequence rows schema

The schema of the sequencerows relation matches the sequence that is specified in the id or externalId option. Apart from the sequence columns, you need a non-nullable rowNumber column of type long. You also need the externalId column, which allows you to write to multiple sequences as long as they have the same schema as the externalId or id passed with the .option().

Labels schema

Column name Type Nullable
externalId string No
name string No
description string Yes

Relationships schema

Column name Type Nullable Filter pushdown ?
externalId string No equality
sourceExternalId string No equality
sourceType string No equality
targetExternalId string No equality
targetType string No equality
startTime timestamp Yes comparison, equality
endTime timestamp Yes comparison, equality
confidence double Yes comparison
labels array(string) Yes equality
dataSetId long Yes equality
lastUpdatedTime timestamp No comparison, equality

Data sets schema

Column name Type Nullable Filter pushdown ?
externalId string Yes equality, prefix (LIKE 'xyz%')
name string Yes equality
description string Yes -
metadata map(string, string) Yes -
writeProtected string No equality
lastUpdatedTime timestamp No comparison, equality

View centric

Nodes schema with view

Column name Type Nullable Filter pushdown ?
space string No equality
externalId string No equality
Mandatory properties of the view No

Nodes schema without view

Column name Type Nullable Filter pushdown ?
space string No equality
externalId string No equality

Edges schema with view

Column name Type Nullable Filter pushdown ?
space string No equality
externalId string No equality
type struct No equality
startNode struct No equality
endNode struct No equality
Mandatory properties of the view No

Edges schema without view (aka connection definition)

Column name Type Nullable Filter pushdown ?
space string No equality
externalId string No equality
startNode struct No equality
endNode struct No equality

Model centric

Instances schema of type

Column name Type Nullable Filter pushdown ?
space string No equality
externalId string No equality
type struct No equality
startNode struct No equality
endNode struct No equality
Mandatory properties of the type No

Instances schema of relationship

Column name Type Nullable Filter pushdown ?
space string No equality
externalId string No equality
startNode struct No equality
endNode struct No equality

Examples by resource types

Assets

Learn more about assets here.

// Scala Example. See Python example below.

// Read assets from your project into a DataFrame
val df = spark.read.format("cognite.spark.v1")
 .option("type", "assets")
 .load()

// Register your assets in a temporary view
df.createTempView("assets")

// Create a new asset and write to CDF
// Note that parentId, asset type IDs, and asset type field IDs have to exist.
val assetColumns = Seq("externalId", "name", "parentId", "description", "metadata", "source",
"id", "createdTime", "lastupdatedTime")
val someAsset = Seq(
("Some external ID", "asset name", "This is another asset", Map("sourceSystem"->"MySparkJob"), "some source",
99L, 0L, 0L))

val someAssetDf = spark
  .sparkContext
  .parallelize(someAsset)
  .toDF(assetColumns:_*)

// Write the new asset to CDF, ensuring correct schema by borrowing the schema of the df from CDF
spark
  .sqlContext
  .createDataFrame(someAssetDf.rdd, df.schema)
  .write
  .insertInto("assets")
# Python Example

# Read assets from your project into a DataFrame
df = spark.read.format("cognite.spark.v1") \
    .option("type", "assets") \
    .load()

# Register your assets in a temporary view
df.createTempView("assets")

# Create a new asset and write to CDF
# Note that parentId, asset type IDs, and asset type field IDs have to exist. You might want to change the columns here as per your requirements
assetColumns = ["externalId", "name", "parentId", "description", "metadata", "source", "id", "createdTime", "lastupdatedTime", "rootId", "aggregates", "dataSetId", "parentExternalId"]

someAsset = [["Some external ID", "asset name", 0, "This is another asset", {"sourceSystem": "MySparkJob"}, "some source", 99, 0, 0, "", "", "", ""]]

someAssetDf = spark.sparkContext \
    .parallelize(someAsset) \
    .toDF(assetColumns)


# Write the new asset to CDF, ensuring correct schema by borrowing the schema of the df from CDF
spark.createDataFrame(someAssetDf.rdd, df.schema) \
    .write \
    .insertInto("assets")

Time series

Learn more about time series here.

// Scala Example. See Python example below.

// Get all the time series from your project
val df = spark.read.format("cognite.spark.v1")
  .option("type", "timeseries")
  .load()
df.createTempView("timeseries")

// Read some new time series data from a csv file
val timeSeriesDf = spark.read.format("csv")
  .option("header", "true")
  .load("timeseries.csv")

// Ensure correct schema by copying the columns in the DataFrame read from the project.
// Note that the time series must already exist in the project before data can be written to it, based on the ´name´ column.
timeSeriesDf.select(df.columns.map(col):_*)
  .write
  .insertInto("timeseries")

// Delete all time series you just created
timeSeriesDf
  .write
  .format("cognite.spark.v1")
  .option("type", "timeseries")
  .option("onconflict", "delete")
  .save()
# Python Example

# Get all the time series from your project
df = spark.read.format("cognite.spark.v1") \
    .option("type", "timeseries") \
    .load()

df.createTempView("timeseries")

# Read some new time series data from a csv file
timeSeriesDf = spark.read.format("csv") \
    .option("header", "true") \
    .load("timeseries.csv")

# Ensure correct schema by copying the columns in the DataFrame read from the project.
# Note that the time series must already exist in the project before data can be written to it, based on the ´name´ column.
timeSeriesDf.select(df.columns.map(col)) \
    .write \
    .insertInto("timeseries")

# Delete all time series you just created
timeSeriesDf \
    .write \
    .format("cognite.spark.v1") \
    .option("type", "timeseries") \
    .option("onconflict", "delete") \
    .save()

Data points

Data points are always related to a time series. To read data points you need to filter by a valid time series id, otherwise an empty DataFrame is returned. Important: Be careful when using caching with this resource type. If you cache the result of a filter and then apply another filter, you do not trigger more data to be read from CDF and end up with an empty DataFrame.

Numerical data points

To read numerical data points from CDF, use the .option("type", "datapoints") option. For numerical data points you can also request aggregated data by filtering by aggregation and granularity.

  • aggregation: Numerical data points can be aggregated to reduce the amount of data transferred in query responses and improve performance. You can specify one or more aggregates (for example average, minimum and maximum) and also the time granularity for the aggregates (for example 1h for one hour). If the aggregate option is NULL, or not set, data points return the raw time series data.

  • granularity: Aggregates are aligned to the start time modulo of the granularity unit. For example, if you ask for daily average temperatures since Monday afternoon last week, the first aggregated data point contains averages for the whole of Monday, the second for Tuesday, etc.

// Scala Example. See Python example below.

// Get the datapoints from publicdata
val df = spark.read.format("cognite.spark.v1")
  .option("type", "datapoints")
  .load()

// Create the view to enable SQL syntax
df.createTempView("datapoints")

// Read the raw datapoints from the VAL_23-FT-92537-04:X.Value time series.
val timeseriesId = 3385857257491234L
val timeseries = spark.sql(s"select * from datapoints where id = $timeseriesId")

// Read aggregate data from the same time series
val timeseriesAggregated = spark.sql(s"select * from datapoints where id = $timeseriesId" +
s"and aggregation = 'min' and granularity = '1d'")
# Get the datapoints from publicdata
df = spark.read.format("cognite.spark.v1") \
    .option("type", "datapoints") \
    .load()

# Create the view to enable SQL syntax
df.createTempView("datapoints")

# Read the raw datapoints from the VAL_23-FT-92537-04:X.Value time series.
timeseriesId = 3385857257491234


query = "select * from datapoints where id = %d" % timeseriesId
timeseries = spark.sql(query)

# Read aggregate data from the same time series
timeseriesAggregated = spark.sql("select * from datapoints where id = %d" %timeseriesId  +
" and aggregation = 'min' and granularity = '1d'")

String data points

To read string data points from CDF, provide the .option("type", "stringdatapoints") option.

// Scala Example. See Python example below.

// Get the datapoints from publicdata
val df = spark.read.format("cognite.spark.v1")
  .option("type", "stringdatapoints")
  .load()

// Create the view to enable SQL syntax
df.createTempView("stringdatapoints")

// Read the raw datapoints from the VAL_23-PIC-96153:MODE time series.
val timeseriesId = 6536948395539605L
val timeseries = spark.sql(s"select * from stringdatapoints where id = $timeseriesId")
# Python Example

# Get the datapoints from publicdata
df = spark.read.format("cognite.spark.v1") \
    .option("type", "stringdatapoints") \
    .load()

# Create the view to enable SQL syntax
df.createTempView("stringdatapoints")

# Read the raw datapoints from the VAL_23-PIC-96153:MODE time series.
timeseriesId = 6536948395539605
timeseries = spark.sql("select * from stringdatapoints where id = %d" % timeseriesId)

Events

Learn more about events here

// Scala Example. See Python example below.

// Read events from `publicdata`
val df = spark.read.format("cognite.spark.v1")
  .option("type", "events")
  .load()

// Insert the events in your own project using .save()
import org.apache.spark.sql.functions._
df.withColumn("source", lit("publicdata"))
  .write.format("cognite.spark.v1")
  .option("onconflict", "abort")
  .save()

// Get a reference to the events in your project
val myProjectDf = spark.read.format("cognite.spark.v1")
  .option("type", "events")
  .load()
myProjectDf.createTempView("events")

// Update the description of all events from Open Industrial Data
spark.sql("""
 |select 'Manually copied data from publicdata' as description,
 |id,
 |from events
 |where source = 'publicdata'
""".stripMargin)
.write.format("cognite.spark.v1")
.option("onconflict", "update")
.save()
# Python Example

# Read events from `publicdata`
df = spark.read.format("cognite.spark.v1") \
    .option("type", "events") \
    .load()

# Insert the events in your own project using .save()
from pyspark.sql.functions import lit
df.withColumn("source", lit("publicdata")) \
    .write.format("cognite.spark.v1") \
    .option("type", "events") \
    .option("onconflict", "abort") \
    .save()

# Get a reference to the events in your project
myProjectDf = spark.read.format("cognite.spark.v1") \
    .option("type", "events") \
    .load()
myProjectDf.createTempView("events")

# Update the description of all events from Open Industrial Data
spark.sql(
    "select 'Manually copied data from publicdata' as description," \
    " id," \
    " from events" \
    " where source = 'publicdata'") \
    .write.format("cognite.spark.v1") \
    .option("onconflict", "update") \
    .save()

Files metadata

Learn more about files here

// Read files metadata from publicdata
val df = spark.read.format("cognite.spark.v1")
  .option("type", "files")
  .load()

df.groupBy("fileType").count().show()

// Register your files in a temporary view
df.createTempView("files")


// Insert the files in your own project using .save()
spark.sql(s"""
      |select 'example-externalId' as externalId,
      |'example-name' as name,
      |'text' as source""")
  .write.format("cognite.spark.v1")
  .option("type", "files")
  .option("onconflict", "abort")
  .save()

//You can also insert using insertInto(). But you need to make sure the the schema is matched correctly.
 spark.sql(s"""
                |select "name-using-insertInto()" as name,
                |null as id,
                |'text' as source,
                |'externalId-using-insertInto()' as externalId,
                |null as mimeType,
                |null as metadata,
                |null as assetIds,
                |null as datasetId,
                |null as sourceCreatedTime,
                |null as sourceModifiedTime,
                |null as securityCategories,
                |null as uploaded,
                |null as createdTime,
                |null as lastUpdatedTime,
                |null as uploadedTime,
                |null as uploadUrl
     """.stripMargin)
      .select(df.columns.map(col):_*)
      .write
      .insertInto("files")
# Python Example

# Read files metadata from publicdata
df = spark.read.format("cognite.spark.v1") \
  .option("type", "files") \
  .load()

df.groupBy("fileType").count().show()

# Register your files in a temporary view
df.createTempView("files")

# Insert the files in your own project using .save()
spark.sql(
    "select 'example-externalId' as externalId," \
    " 'example-name' as name," \
    " 'text' as source") \
  .write.format("cognite.spark.v1") \
  .option("type", "files") \
  .option("onconflict", "abort") \
  .save()

# You can also insert data using insertInto(). But you need to make sure the the schema is matched correctly.
# The example using insertInto() is given above in Scala example.

3D models and revisions metadata

Learn more about 3D models and revisions here

Note that the Open Industrial Data project does not have any 3D models. To test this example, you need a project with existing 3D models. There are four options for listing metadata about 3D models: 3dmodels, 3dmodelrevisions, 3dmodelrevisionmappings and 3dmodelrevisionnodes.

// Read 3D models metadata from a project with 3D models and revisions
val df = spark.read.format("cognite.spark.v1")
  .option("type", "3dmodels")
  .load()

df.show()
# Python Example

# Read 3D models metadata from a project with 3D models and revisions
df = spark.read.format("cognite.spark.v1") \
    .option("type", "3dmodels") \
    .load()

df.show()

Sequences

Learn more about sequences here

// Scala Example. See Python example below.

// List all sequences
val df = spark.read.format("cognite.spark.v1")
  .option("type", "sequences")
  .load()

// Create new sequence using Spark SQL
spark.sql("""
 |select 'c|$key' as externalId,
 |'c seq' as name,
 |'Sequence C detailed description' as description,
 |array(
 |  named_struct(
 |    'metadata', map('foo', 'bar', 'nothing', NULL),
 |    'name', 'column 1',
 |    'externalId', 'c_col1',
 |    'valueType', 'STRING'
 |  )
 |) as columns
""".stripMargin)
.write.format("cognite.spark.v1")
.option("type", "sequences")
.option("onconflict", "abort")
.save()
# Python Example

# List all sequences
df = spark.read.format("cognite.spark.v1") \
    .option("type", "sequences") \
    .load()

# Create new sequence using Spark SQL
spark.sql(
    "select 'c|$key' as externalId," \
    " 'c seq' as name," \
    " 'Sequence C detailed description' as description," \
    " array(" \
    "   named_struct(" \
    "     'metadata', map('foo', 'bar', 'nothing', NULL)," \
    "     'name', 'column 1'," \
    "     'externalId', 'c_col1'," \
    "     'valueType', 'STRING'" \
    "   )" \
    " ) as columns") \
    .write.format("cognite.spark.v1") \
    .option("type", "sequences") \
    .option("onconflict", "abort") \
    .save()

Sequence Rows

Learn more about sequences here

One of two additional options must be specified:

  • id: Cognite internal id of the sequence that is read or written to
  • externalId: the external Id of the sequence that is read or written to
// Scala Example. See Python example below.

// Read sequence rows
val df = spark.read.format("cognite.spark.v1")
  .option("type", "sequencerows")
  .option("id", sequenceId) // or you can use the "externalId" option
  .load()

// Insert the rows into another sequence using .save()
import org.apache.spark.sql.functions._
import org.apache.spark.sql.functions.lit

df
  .withColumn("externalId", lit("my-sequence")) // Required when writing to support writing to multiple sequences
  .write.format("cognite.spark.v1")
  .option("type", "sequencerows")
  .option("onconflict", "upsert")
  .option("externalId", "my-sequence")
  .save()
# Python Example

# Read sequence rows
df = spark.read.format("cognite.spark.v1") \
    .option("type", "sequencerows") \
    .option("id", sequenceId) \
    .load()

# Insert the rows into another sequence using .save()
from pyspark.sql.functions import lit
df \
    .withColumn("externalId", "my-sequence") \  # Required when writing to support writing to multiple sequences
    .write.format("cognite.spark.v1") \
    .option("type", "sequencerows") \
    .option("onconflict", "upsert") \
    .option("externalId", "my-sequence") \
    .save()

Labels

Learn more about labels here

Note that labels can not be updated, but can only be read, created, or deleted. If you want to change a label, you can first delete it, and then recreate it with the same external id, but the new label will have a different Cognite internal id.

# Python Example

# Read labels
df = spark.read.format("cognite.spark.v1") \
    .option("type", "labels") \
    .load()

df.show()


# Write labels
spark.sql(
    "select 'label-externalId' as externalId," \
    " 'new-label' as name," \
    " 'text' as description") \
  .write.format("cognite.spark.v1") \
  .option("type", "labels") \
  .save()

Relationships

Learn more about relationships here

Note that relationships can't be updated, but can only be read, created, or deleted. If you want to change a relationship, you can first delete it, and then recreate it with the same external id. externalId, sourceExternalId, sourceType, targetExternalId, targetType can't be null.

// Scala Example

// Read relationships
df = spark.read
  .format("cognite.spark.v1")
  .option("type", "relationships")
  .load()

df.show()


// Write relationships
spark
  .sql(
    s"""select 'relationships_external_id' as externalId,
       |'my_asset1' as sourceExternalId,
       |'asset' as sourceType,
       |'my_asset2' as targetExternalId,
       |'asset' as targetType,
       | array('scala-sdk-relationships-test-label1') as labels,
       | 0.7 as confidence,
       | cast(from_unixtime(0) as timestamp) as startTime,
       | cast(from_unixtime(1) as timestamp) as endTime""".stripMargin)
  .write
  .format("cognite.spark.v1")
  .option("type", "relationships")
  .save() 
# Python Example

df = spark.read.format("cognite.spark.v1") \
    .option("type", "relationships") \
    .load()

df.show()


# Get a reference to the relationships in your project
myProjectDf = spark.read.format("cognite.spark.v1") \
    .option("type", "relationships") \
    .load()
myProjectDf.createTempView("relationships")


# Insert the relationships in your own project using .save()
spark.sql(
    "select 'relationships_external_id' as externalId, \
      'my_asset1' as sourceExternalId, \
      'asset' as sourceType, \
      'my_asset2' as targetExternalId, \
      'asset' as targetType, \
      array('scala-sdk-relationships-test-label1') as labels, \
      0.7 as confidence, \
      cast(from_unixtime(0) as timestamp) as startTime, \
      cast(from_unixtime(1) as timestamp) as endTime") \
  .write.format("cognite.spark.v1") \
  .option("type", "relationships") \
  .option("onconflict", "abort") \
  .save()

Data sets

Learn more about labels here

Note that data sets can be read, created and updated, but not deleted.

# Python Example

# Read data sets
df = spark.read.format("cognite.spark.v1") \
    .option("type", "datasets") \
    .load()

df.show()


# Write labels
spark.sql(
    "select 'new-datasets' as externalId," \
    " 'New Dataset' as name," \
    " 'text' as description") \
    " null as metadata") \
    " true as writeProtected") \
  .write.format("cognite.spark.v1") \
  .option("type", "datasets") \
  .save()

Nodes

Learn more about labels here

Note that nodes can be read, created, updated and deleted. Note view is optional, not needed for writing nodes without a view

# Python Example

# Read nodes
df = spark.read.format("cognite.spark.v1") \
    .option("tokenUri", https://login.microsoftonline.com/<Directory (tenant) ID>/oauth2/v2.0/token) \
    .option("clientId", client_ID) \
    .option("clientSecret", client_secret) \
    .option("project", project) \
    .option("scopes", scope) \
    .option("baseUrl", baseUrl) \
    .option("instanceType","node")
    .option("type", "instances")
    .option("space", ViewSpace")
    .option("externalId", ViewExternalId)
    .option("version", ViewVersion)
    .option("instanceSpace", instanceSpace)
    .load()

df.show()


# Write nodes
spark.sql(
    "select 'space' as space, 'ViewExternaldId' as externalId") \
    .write.format("cognite.spark.v1") \
    .option("tokenUri", https://login.microsoftonline.com/<Directory (tenant) ID>/oauth2/v2.0/token) \
    .option("clientId", client_ID) \
    .option("clientSecret", client_secret) \
    .option("project", project) \
    .option("scopes", scope) \
    .option("baseUrl", baseUrl) \
    .option("instanceType","node") \
    .option("type", "instances") \
    .option("space", ViewSpace) \
    .option("externalId", ViewExternalId) \
    .option("version", ViewVersion) \
    .option("onConflict", "upsert") \
    .save()

Edges

Learn more about labels here

Note that Edges can be read, created, updated and deleted.

# Python Example

# Read edges with view in your data model
df = spark.read
  .format("cognite.spark.v1")
  .option("tokenUri", https://login.microsoftonline.com/<Directory (tenant) ID>/oauth2/v2.0/token)
  .option("clientId", client_ID)
  .option("clientSecret", client_secret)
  .option("project", project)
  .option("scopes", scope)
  .option("baseUrl", baseUrl)
  .option("instanceType","edge")
  .option("type", "instances")
  .option("space", ViewSpace)
  .option("externalId", ViewExternalId)
  .option("version", ViewVersion)
  .option("instanceSpace", instanceSpace)
  .load()

df.show()

# Write edges with view in your data model
spark.sql(
    "select 'ViewSpace' as space, 'ViewExternaldId' as externalId,  named_struct('spaceExternalId', 'ViewSpace', 'externalId', 'ViewExternaldId') as type, named_struct('spaceExternalId', 'spaceExternalId', 'externalId', 'startNodeExtId') as  startNode, named_struct('spaceExternalId', 'spaceExternalId', 'externalId', 'endNodeExtId') as endNode") \
    .write.format("cognite.spark.v1") \
    .option("tokenUri", https://login.microsoftonline.com/<Directory (tenant) ID>/oauth2/v2.0/token) \
    .option("clientId", client_ID) \
    .option("clientSecret", client_secret) \
    .option("project", project) \
    .option("scopes", scope) \
    .option("baseUrl", baseUrl) \
    .option("instanceType","node") \
    .option("type", "instances") \
    .option("space", ViewSpace) \
    .option("externalId", ViewExternalId) \
    .option("existingVersion", existingVersion) \
    .option("onConflict", "upsert") \
    .save() \

# Read edges without view (aka connection definition) in your data model
df = spark.read
  .format("cognite.spark.v1")
  .option("tokenUri",  https://login.microsoftonline.com/<Directory (tenant) ID>/oauth2/v2.0/token)
  .option("clientId", client_ID)
  .option("clientSecret", client_secret)
  .option("project", project)
  .option("scopes", scope)
  .option("baseUrl", baseUrl)
  .option("instanceType","edge")
  .option("type", "instances")
  .option("edgeTypeSpace", edgeTypeSpace)
  .option("edgeTypeExternalId", edgeTypeExternalId)
  .option("collectMetrics", true)
  .load()

df.show()

# Write edges without view (aka connection definition) in your data model
spark.sql(
 "select 'edgeTypeSpace' as space, 'edgeTypeExternalId' as externalId,  named_struct('spaceExternalId', 'edgeTypeSpace', 'externalId', 'edgeTypeExternalId') as type, named_struct('spaceExternalId', 'authors', 'externalId', 'externalIdAuthors1') as  startNode, named_struct('spaceExternalId', 'books', 'externalId', 'externalIdBooks1') as endNode") \
  .write.format("cognite.spark.v1") \
  .option("tokenUri",  https://login.microsoftonline.com/<Directory (tenant) ID>/oauth2/v2.0/token)\
  .option("clientId", client_ID)\
  .option("clientSecret", client_secret)\
  .option("project", project)\
  .option("scopes", scope)\
  .option("baseUrl", baseUrl)\
  .option("instanceType","edge")\
  .option("type", "instances")\
  .option("edgeTypeSpace", edgeTypeSpace)\
  .option("edgeTypeExternalId", edgeTypeExternalId)\
  .option("onConflict", "upsert") \
  .save()

Instances

  • Instances to a type
# Python Example

# Reading instances from type
df = spark.read
  .format("cognite.spark.v1")
  .option("baseUrl", baseUrl)
  .option("tokenUri", "https://login.microsoftonline.com/<Directory (tenant) ID>/oauth2/v2.0/token")
  .option("clientId", clientId)
  .option("clientSecret", clientSecret)
  .option("project", project)
  .option("scopes", scope)
  .option("instanceType","instances")
  .option("type", "instances")
  .option("modelSpace", modelSpace)
  .option("modelExternalId", modelExternalId)
  .option("modelVersion", modelVersion)
  .option("viewExternalId", viewExternalId)
  .load()

df.show()


# Writing instances to a type
spark.sql("select 'instanceSpace' as space, 'instanceExternalId' as externalId, 'throughModelProp1' as stringProp1, 'throughModelProp2' as stringProp2" )
  .write.format("cognite.spark.v1") 
  .option("baseUrl", baseUrl)
  .option("tokenUri", "https://login.microsoftonline.com/<Directory (tenant) ID>/oauth2/v2.0/token")
  .option("clientId", clientId)
  .option("clientSecret", clientSecret)
  .option("project", project)
  .option("scopes", scope)
  .option("instanceType","instances")
  .option("type", "instances")
  .option("modelSpace", modelSpace)
  .option("modelExternalId", modelExternalId)
  .option("modelVersion", modelVersion)
  .option("viewExternalId", viewExternalId)
  .option("onconflict",  "upsert")
  .save()
  • Instances to a relationship
# Python Example

# Read instances from a relationship
df = spark.read
  .format("cognite.spark.v1")
  .option("baseUrl",baseUrl)
  .option("tokenUri", "https://login.microsoftonline.com/<Directory (tenant) ID>/oauth2/v2.0/token")
  .option("clientId", clientId)
  .option("clientSecret", clientSecret)
  .option("project", project)
  .option("scopes", scope)
  .option("instanceType","instances")
  .option("type", "instances")
  .option("modelSpace", modelSpace)
  .option("modelExternalId", modelExternalId)
  .option("modelVersion", modelVersion)
  .option("viewExternalId", viewExternalId)
  .option("connectionPropertyName", connectionPropertyName)
  .load()

df.show()



# Write instances to a relationship
spark.sql("select 'instanceSpace' as space, 'instanceExternalId' as externalId,  node_reference('spaceExternalId of type', 'externalId of type') as startNode ,node_reference('spaceExternalId of type', 'externalId of type') as endNode" )
  .write.format("cognite.spark.v1") 
  .option("baseUrl", baseUrl)
  .option("tokenUri", "https://login.microsoftonline.com/<Directory (tenant) ID>/oauth2/v2.0/token")
  .option("clientId", clientId)
  .option("clientSecret", clientSecret)
  .option("project", project)
  .option("scopes", scope)
  .option("instanceType","instances")
  .option("type", "instances")
  .option("modelSpace", modelSpace)
  .option("modelExternalId", modelExternalId)
  .option("modelVersion", modelVersion)
  .option("viewExternalId", viewExternalId)
  .option("connectionPropertyName", connectionPropertyName)
  .option("onconflict",  "upsert")
  .save()

RAW tables

Learn more about RAW tables here.

RAW tables are organized in databases and tables that you need to provide as options to the DataFrameReader. publicdata does not contain any RAW tables so you'll need access to a project with raw table data.

Two additional options are required:

  • database: The name of the database in Cognite Data Fusion's RAW storage to use. The database must exist, and will not be created if it does not.

  • table: The name of the table in Cognite Data Fusion's RAW storage to use. The table must exist in the database specified in the database option, and will not be created if it does not.

Optionally, you can have Spark infer the DataFrame schema with the following options:

  • inferSchema: Set this to "true" to enable schema inference. You can also use the inferred schema can also be used for inserting new rows.

  • inferSchemaLimit: The number of rows to use for inferring the schema of the table. The default is to read all rows.

  • collectSchemaInferenceMetrics: Whether metrics should be collected about the read operations for schema inference.

  • rawEnsureParent: When set to true, the parent database and table will be creates if it does not exists already.

val df = spark.read.format("cognite.spark.v1")
  .option("type", "raw")
  .option("database", "database-name") // a RAW database from your project
  .option("table", "table-name") // name of a table in "database-name"
  .load()
df.createTempView("tablename")

// Insert some new values
spark.sql("""insert into tablename values ("key", "values")""")
# Python Example

# database-name -> a RAW database from your project
# table-name -> name of a table in "database-name"
df = spark.read.format("cognite.spark.v1") \
  .option("type", "raw") \
  .option("database", "database-name") \
  .option("table", "table-name") \
  .load()

df.createTempView("tablename")

# Insert some new values
spark.sql("insert into tablename values ('key', 'values')")

For more details on how to insert a dataframe into a RAW table, see the example, where we show how to backup assets to a RAW table

Comprehensive examples

Build the project with sbt

The project runs read-only integration tests against the Open Industrial Data project. Navigate to https://hub.cognite.com/open-industrial-data-211 to get a Client Secret and store it in the TEST_OIDC_READ_CLIENT_SECRET environment variable along with TEST_OIDC_READ_CLIENT_ID and TEST_OIDC_READ_TENANT. The value of Client ID and Tenant ID can be found here

If you are using the SBT shell in IntelliJ or similar and want to get it to pick up environment variables from a file, you can create a file in this directory named .env containing environment variables, one per line, of the format ENVIRONMENT_VARIABLE_NAME=value. See sbt-dotenv for more information.

Set up

  1. First run sbt compile to generate Scala sources for protobuf.

  2. Run the Python files scripts/createThreeDData.py and scripts/createFilesMetaData.py (You need to install the cognite-sdk-python and set the PROJECT environment variables).

This uploads a 3D model to your project that you can use for testing.

Run the tests

To run all tests, run sbt test.

To run groups of tests, enter sbt shell mode sbt>

To run only the read-only tests, run sbt> testOnly -- -n ReadTest

To run only the write tests, run sbt> testOnly -- -n WriteTest

To run all tests except the write tests, run sbt> testOnly -- -l WriteTest

To skip the read/write tests in assembly, add test in assembly := {} to build.sbt, or run:

  • Windows: sbt "set test in assembly := {}" assembly

  • Linux/macos: sbt 'set test in assembly := {}' assembly

Run the project locally with spark-shell

To download the spark data source, simply add the Maven coordinates for the package using the --packages flag.

Get access for the Open Industrial Data project at https://openindustrialdata.com and run the following commands (replace <release> with the release you'd like, for example 1.2.0). See also https://hub.cognite.com/open-industrial-data-211/openid-connect-on-open-industrial-data-993 for OIDC access setup

$> spark-shell --packages com.cognite.spark.datasource:cdf-spark-datasource_2.11:<latest-release>
scala> val df = spark.read.format("cognite.spark.v1")
  .option("batchSize", "1000")
  .option("limitPerPartition", "1000")
  .option("type", "assets")
  .load()

df: org.apache.spark.sql.DataFrame = [name: string, parentId: bigint ... 3 more fields]

scala> df.count
res0: Long = 1000

Note that if you're on an older version than 1.1.0 you'll need to use the old name, cdp-spark-datasource.

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