org.apache.nifi.processors.standard

Class EvaluateJsonPath

java.lang.Object

org.apache.nifi.components.AbstractConfigurableComponent

org.apache.nifi.processor.AbstractSessionFactoryProcessor

org.apache.nifi.processor.AbstractProcessor

org.apache.nifi.processors.standard.AbstractJsonPathProcessor

org.apache.nifi.processors.standard.EvaluateJsonPath

All Implemented Interfaces:

ConfigurableComponent, Processor

@EventDriven
 @SideEffectFree
 @SupportsBatching
 @Tags(value={"JSON","evaluate","JsonPath"})
 @InputRequirement(value=INPUT_REQUIRED)
 @CapabilityDescription(value="Evaluates one or more JsonPath expressions against the content of a FlowFile. The results of those expressions are assigned to FlowFile Attributes or are written to the content of the FlowFile itself, depending on configuration of the Processor. JsonPaths are entered by adding user-defined properties; the name of the property maps to the Attribute Name into which the result will be placed (if the Destination is flowfile-attribute; otherwise, the property name is ignored). The value of the property must be a valid JsonPath expression. A Return Type of \'auto-detect\' will make a determination based off the configured destination. When \'Destination\' is set to \'flowfile-attribute,\' a return type of \'scalar\' will be used. When \'Destination\' is set to \'flowfile-content,\' a return type of \'JSON\' will be used.If the JsonPath evaluates to a JSON array or JSON object and the Return Type is set to \'scalar\' the FlowFile will be unmodified and will be routed to failure. A Return Type of JSON can return scalar values if the provided JsonPath evaluates to the specified value and will be routed as a match.If Destination is \'flowfile-content\' and the JsonPath does not evaluate to a defined path, the FlowFile will be routed to \'unmatched\' without having its contents modified. If Destination is flowfile-attribute and the expression matches nothing, attributes will be created with empty strings as the value, and the FlowFile will always be routed to \'matched.\'")
 @DynamicProperty(name="A FlowFile attribute(if <Destination> is set to \'flowfile-attribute\')",
                 value="A JsonPath expression",
                 description="If <Destination>=\'flowfile-attribute\' then that FlowFile attribute will be set to any JSON objects that match the JsonPath.  If <Destination>=\'flowfile-content\' then the FlowFile content will be updated to any JSON objects that match the JsonPath.")
public class EvaluateJsonPath
extends AbstractJsonPathProcessor

Field Summary

Fields

Modifier and Type	Field and Description
static PropertyDescriptor	DESTINATION
static java.lang.String	DESTINATION_ATTRIBUTE
static java.lang.String	DESTINATION_CONTENT
static PropertyDescriptor	PATH_NOT_FOUND
static java.lang.String	PATH_NOT_FOUND_IGNORE
static java.lang.String	PATH_NOT_FOUND_WARN
static Relationship	REL_FAILURE
static Relationship	REL_MATCH
static Relationship	REL_NO_MATCH
static PropertyDescriptor	RETURN_TYPE
static java.lang.String	RETURN_TYPE_AUTO
static java.lang.String	RETURN_TYPE_JSON
static java.lang.String	RETURN_TYPE_SCALAR

Fields inherited from class org.apache.nifi.processors.standard.AbstractJsonPathProcessor

NULL_VALUE_DEFAULT_REPRESENTATION

Constructor Summary

Constructors

Constructor and Description
EvaluateJsonPath()

Method Summary

Modifier and Type	Method and Description
protected java.util.Collection<ValidationResult>	customValidate(ValidationContext context) Allows subclasses to perform their own validation on the already set properties.
java.util.Set<Relationship>	getRelationships()
protected PropertyDescriptor	getSupportedDynamicPropertyDescriptor(java.lang.String propertyDescriptorName) Used to allow subclasses to determine what PropertyDescriptor if any to use when a property is requested for which a descriptor is not already registered.
protected java.util.List<PropertyDescriptor>	getSupportedPropertyDescriptors() Allows subclasses to register which property descriptor objects are supported.
protected void	init(ProcessorInitializationContext context) Provides subclasses the ability to perform initialization logic
void	onPropertyModified(PropertyDescriptor descriptor, java.lang.String oldValue, java.lang.String newValue) Hook method allowing subclasses to eagerly react to a configuration change for the given property descriptor.
void	onRemoved(ProcessContext processContext) Provides cleanup of the map for any JsonPath values that may have been created.
void	onScheduled(ProcessContext processContext)
void	onTrigger(ProcessContext processContext, ProcessSession processSession)
void	onUnscheduled()

Methods inherited from class org.apache.nifi.processor.AbstractProcessor

onTrigger

Methods inherited from class org.apache.nifi.processor.AbstractSessionFactoryProcessor

getControllerServiceLookup, getIdentifier, getLogger, getNodeTypeProvider, initialize, isConfigurationRestored, isScheduled, toString, updateConfiguredRestoredTrue, updateScheduledFalse, updateScheduledTrue

Methods inherited from class org.apache.nifi.components.AbstractConfigurableComponent

equals, getPropertyDescriptor, getPropertyDescriptors, hashCode, validate

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.apache.nifi.components.ConfigurableComponent

getPropertyDescriptor, getPropertyDescriptors, validate

Field Detail

DESTINATION_ATTRIBUTE

public static final java.lang.String DESTINATION_ATTRIBUTE

See Also:

Constant Field Values

DESTINATION_CONTENT

public static final java.lang.String DESTINATION_CONTENT

See Also:

Constant Field Values

RETURN_TYPE_AUTO

public static final java.lang.String RETURN_TYPE_AUTO

See Also:

Constant Field Values

RETURN_TYPE_JSON

public static final java.lang.String RETURN_TYPE_JSON

See Also:

Constant Field Values

RETURN_TYPE_SCALAR

public static final java.lang.String RETURN_TYPE_SCALAR

See Also:

Constant Field Values

PATH_NOT_FOUND_IGNORE

public static final java.lang.String PATH_NOT_FOUND_IGNORE

See Also:

Constant Field Values

PATH_NOT_FOUND_WARN

public static final java.lang.String PATH_NOT_FOUND_WARN

See Also:

Constant Field Values

DESTINATION

public static final PropertyDescriptor DESTINATION

RETURN_TYPE

public static final PropertyDescriptor RETURN_TYPE

PATH_NOT_FOUND

public static final PropertyDescriptor PATH_NOT_FOUND

REL_MATCH

public static final Relationship REL_MATCH

REL_NO_MATCH

public static final Relationship REL_NO_MATCH

REL_FAILURE

public static final Relationship REL_FAILURE

Constructor Detail

EvaluateJsonPath

public EvaluateJsonPath()

Method Detail

init

protected void init(ProcessorInitializationContext context)

Description copied from class: AbstractSessionFactoryProcessor

Provides subclasses the ability to perform initialization logic

Overrides:

init in class AbstractSessionFactoryProcessor

Parameters:

context - in which to perform initialization

customValidate

protected java.util.Collection<ValidationResult> customValidate(ValidationContext context)

Description copied from class: AbstractConfigurableComponent

Allows subclasses to perform their own validation on the already set properties. Since each property is validated as it is set this allows validation of groups of properties together. Default return is an empty set. This method will be called only when it has been determined that all property values are valid according to their corresponding PropertyDescriptor's validators.

Overrides:

customValidate in class AbstractConfigurableComponent

Parameters:

context - provides a mechanism for obtaining externally managed values, such as property values and supplies convenience methods for operating on those values

Returns:

Collection of ValidationResult objects that will be added to any other validation findings - may be null

getRelationships

public java.util.Set<Relationship> getRelationships()

Specified by:

getRelationships in interface Processor

Overrides:

getRelationships in class AbstractSessionFactoryProcessor

Returns:

Set of all relationships this processor expects to transfer a flow file to. An empty set indicates this processor does not have any destination relationships. Guaranteed non null.

getSupportedPropertyDescriptors

protected java.util.List<PropertyDescriptor> getSupportedPropertyDescriptors()

Description copied from class: AbstractConfigurableComponent

Allows subclasses to register which property descriptor objects are supported. Default return is an empty set.

Overrides:

getSupportedPropertyDescriptors in class AbstractConfigurableComponent

Returns:

PropertyDescriptor objects this processor currently supports

getSupportedDynamicPropertyDescriptor

protected PropertyDescriptor getSupportedDynamicPropertyDescriptor(java.lang.String propertyDescriptorName)

Description copied from class: AbstractConfigurableComponent

Used to allow subclasses to determine what PropertyDescriptor if any to use when a property is requested for which a descriptor is not already registered. By default this method simply returns a null descriptor. By overriding this method processor implementations can support dynamic properties since this allows them to register properties on demand. It is acceptable for a dynamically generated property to indicate it is required so long as it is understood it is only required once set. Dynamic properties by definition cannot be required until used.

This method should be side effect free in the subclasses in terms of how often it is called for a given property name because there is guarantees how often it will be called for a given property name.

Default is null.

Overrides:

getSupportedDynamicPropertyDescriptor in class AbstractConfigurableComponent

Parameters:

propertyDescriptorName - used to lookup if any property descriptors exist for that name

Returns:

new property descriptor if supported

onPropertyModified

public void onPropertyModified(PropertyDescriptor descriptor,
                               java.lang.String oldValue,
                               java.lang.String newValue)

Description copied from class: AbstractConfigurableComponent

Hook method allowing subclasses to eagerly react to a configuration change for the given property descriptor. As an alternative to using this method a processor may simply get the latest value whenever it needs it and if necessary lazily evaluate it.

Specified by:

onPropertyModified in interface ConfigurableComponent

Overrides:

onPropertyModified in class AbstractConfigurableComponent

Parameters:

descriptor - of the modified property

oldValue - non-null property value (previous)

newValue - the new property value or if null indicates the property was removed

onRemoved

@OnRemoved
public void onRemoved(ProcessContext processContext)

Provides cleanup of the map for any JsonPath values that may have been created. This will remove common values shared between multiple instances, but will be regenerated when the next validation cycle occurs as a result of isStale()

Parameters:

processContext - context

onScheduled

@OnScheduled
public void onScheduled(ProcessContext processContext)

onUnscheduled

@OnUnscheduled
public void onUnscheduled()

onTrigger

public void onTrigger(ProcessContext processContext,
                      ProcessSession processSession)
               throws ProcessException

Specified by:

onTrigger in class AbstractProcessor

Throws:

ProcessException