io.cdap.wrangler.service.common

Class AbstractWranglerHandler

java.lang.Object

io.cdap.cdap.internal.api.AbstractProgramDatasetConfigurable<T>

io.cdap.cdap.internal.api.AbstractPluginConfigurable<V>

io.cdap.cdap.api.service.http.AbstractHttpServiceHandler<io.cdap.cdap.api.service.http.SystemHttpServiceContext,io.cdap.cdap.api.service.http.SystemHttpServiceConfigurer>

io.cdap.cdap.api.service.http.AbstractSystemHttpServiceHandler

io.cdap.wrangler.service.common.AbstractWranglerHandler

All Implemented Interfaces:

io.cdap.cdap.api.ProgramLifecycle<io.cdap.cdap.api.service.http.SystemHttpServiceContext>, io.cdap.cdap.api.service.http.HttpServiceHandler<io.cdap.cdap.api.service.http.SystemHttpServiceContext,io.cdap.cdap.api.service.http.SystemHttpServiceConfigurer>

Direct Known Subclasses:

ADLSHandler, BigQueryHandler, ConnectionHandler, DatabaseHandler, DirectivesHandler, FilesystemExplorer, GCSHandler, KafkaHandler, S3Handler, SchemaRegistryHandler, SpannerHandler

public class AbstractWranglerHandler
extends io.cdap.cdap.api.service.http.AbstractSystemHttpServiceHandler

Common functionality for wrangler services.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected static interface	AbstractWranglerHandler.NamespacedResponder<T> Responds to a request within a namespace.

Constructor Summary

Constructors

Constructor and Description
AbstractWranglerHandler()

Method Summary

Modifier and Type	Method and Description
protected Connection	getConnection(NamespacedId connectionId)
protected Connection	getValidatedConnection(ConnectionStore store, NamespacedId connectionId, ConnectionType expectedType) Validates that the specified connection exists and is of the expected type.
protected Connection	getValidatedConnection(NamespacedId connectionId, ConnectionType expectedType)
protected Workspace	getWorkspace(NamespacedId workspaceId)
protected <T> void	respond(io.cdap.cdap.api.service.http.HttpServiceRequest request, io.cdap.cdap.api.service.http.HttpServiceResponder responder, Callable<T> callable) Utility method for executing an endpoint with common error handling built in.
protected <T> void	respond(io.cdap.cdap.api.service.http.HttpServiceRequest request, io.cdap.cdap.api.service.http.HttpServiceResponder responder, String namespace, AbstractWranglerHandler.NamespacedResponder<T> callable) Utility method for executing an endpoint with common error handling and namespace checks built in.
protected boolean	shouldCopyHeader(WorkspaceDataset ws, NamespacedId workspaceId) Return whether the header needs to be copied when creating the pipeline source for the specified workspace.

Methods inherited from class io.cdap.cdap.api.service.http.AbstractSystemHttpServiceHandler

createTable

Methods inherited from class io.cdap.cdap.api.service.http.AbstractHttpServiceHandler

configure, configure, destroy, getConfigurer, getContext, initialize, setProperties

Methods inherited from class io.cdap.cdap.internal.api.AbstractPluginConfigurable

usePlugin, usePlugin, usePluginClass, usePluginClass

Methods inherited from class io.cdap.cdap.internal.api.AbstractProgramDatasetConfigurable

addDatasetModule, addDatasetType, createDataset, createDataset, createDataset, createDataset

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

AbstractWranglerHandler

public AbstractWranglerHandler()

Method Detail

getWorkspace

protected Workspace getWorkspace(NamespacedId workspaceId)

shouldCopyHeader

protected boolean shouldCopyHeader(WorkspaceDataset ws,
                                   @Nullable
                                   NamespacedId workspaceId)
                            throws IOException

Return whether the header needs to be copied when creating the pipeline source for the specified workspace. This just amounts to checking whether parse-as-csv with the first line as a header is used as a directive.

Throws:

IOException

getConnection

protected Connection getConnection(NamespacedId connectionId)

getValidatedConnection

protected Connection getValidatedConnection(NamespacedId connectionId,
                                            ConnectionType expectedType)

getValidatedConnection

@Nullable
protected Connection getValidatedConnection(ConnectionStore store,
                                                      NamespacedId connectionId,
                                                      ConnectionType expectedType)
                                               throws IOException

Validates that the specified connection exists and is of the expected type. Returns null if the connection does not exist or is invalid. Callers should return immediately if a null is returned, as a response has already been sent. This method should only be called from endpoints that use explicit transaction control.

Parameters:

store - the connection store to read from

connectionId - the id of the connection

expectedType - the expected type of the connection

Returns:

the validated connection

Throws:

ConnectionNotFoundException - if the connection does not exist

IOException - if there was an error reading from the store

respond

protected <T> void respond(io.cdap.cdap.api.service.http.HttpServiceRequest request,
                           io.cdap.cdap.api.service.http.HttpServiceResponder responder,
                           Callable<T> callable)

Utility method for executing an endpoint with common error handling built in. A response will always be sent after this method is called so the http responder should not be used after this. The endpoint logic should also not use the responder in any way. If the callable throws a StatusCodeException, the exception's status code and message will be used to create the response. If a JsonSyntaxException is thrown, a 400 response will be sent. If anything else if thrown, a 500 response will be sent. If nothing is thrown, the result of the callable will be sent as json.

Parameters:

request - the http request

responder - the http responder

callable - the endpoint logic to run

respond

protected <T> void respond(io.cdap.cdap.api.service.http.HttpServiceRequest request,
                           io.cdap.cdap.api.service.http.HttpServiceResponder responder,
                           String namespace,
                           AbstractWranglerHandler.NamespacedResponder<T> callable)

Utility method for executing an endpoint with common error handling and namespace checks built in. A response will always be sent after this method is called so the http responder should not be used after this. The endpoint logic should also not use the responder in any way. If the callable throws a StatusCodeException, the exception's status code and message will be used to create the response. If a JsonSyntaxException is thrown, a 400 response will be sent. If anything else if thrown, a 500 response will be sent. If nothing is thrown, the result of the callable will be sent as json.

Parameters:

request - the http request

responder - the http responder

namespace - the namespace to check for

callable - the endpoint logic to run