AttributeValidator

Validates any number of attributes against user-defined test conditions, routing the feature according to the outcome of the test(s) and identifying any tests it has failed.

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Typical Uses

Performing data quality testing
Enforcing data integrity by testing attributes against a set of acceptable conditions
Ensuring attributes meet the requirements of constraints and domains in output databases

How does it work?

The AttributeValidator receives features with attributes to be tested against user-defined Validation Rules.

A wide variety of Validation Rule types are available. The rules are created in a table, and each row consists of the attribute(s) to be validated, the type of test to be done, and any configuration required. An attribute may be tested against any number of rules, and a rule may be applied to any number of attributes.

There are two output ports - Passed and Failed.

Passed features are those whose attributes have passed all Validation Rule tests that have been defined.

If any tests are failed, the features will be output via the Failed port, with descriptions of the failures:

The first test failed will be documented in the new attribute _fme_validation_message.
The first test and any further tests failed will all be documented in the new list attribute _fme_validation_message_list{}.

Tests are evaluated in the order they are listed in the Validation Rules table in the parameters dialog.

Creating Validation Rules

Each rule consists of the attributes to be tested and the test to be performed. The following tests are available.

Validation Rules

Validation Rule

Description

Configuration

Type

Tests if the value is compatible with the chosen Type.

You may test for multiple types by adding additional Validation Rules.

Select the Type to test for.

Boolean	Valid Boolean values are the strings: TRUE, True, true, 1, YES, Yes, yes FALSE, False, false, 0, NO, No, no
Double	Floating-point number
Integer	Integer
Numeric	A number (same behavior as Double)
Alphanumeric	All characters are either a digit (0-9) or a letter (a-z, A-Z). White space, nulls, control codes, punctuation, and accented or extended characters are not included.
String	A sequence of characters. The value is not null or missing, and does not contain any null characters.
XML	Checks for valid XML syntax.
JSON	Checks for valid JSON syntax.
Date	Date in the form yyyymmdd , as in: 20170206
Datetime	Date and time in the form [Date][Time] as in: 20170206111730.135
Datetime With Offset	Date and time with UTC offset in the form [Datetime][UTC offset] as in: 20170206111730.135-08:00
Time	Time in the form hhmmss or hhmmss.123456789, as in: 111730 111730.135
Time With Offset	Time with UTC offset in the form [Time][UTC offset], as in: 111730.135-08:00

In Range

Tests if the value falls within the numeric range specified in set notation.

Open-ended ranges may be defined by leaving either the lower or upper limit blank.

Range values are separated by a comma and enclosed by brackets.

Square brackets - [ ] - indicate inclusive limits (greater than or equal to, less than or equal to).

Round brackets - ( ) - indicate exclusive limits (greater than, less than).

Valid range examples:

(1,9) Greater than 1 and less than 9

[1,9] Greater than or equal to 1 and less than or equal to 9

(1,9] Greater than 1 and less than or equal to 9

(1,) Greater than 1

[,9] Less than or equal to 9

Case

Tests if the value complies with the selected case pattern.

Select a case pattern.

	Valid (Passed) Example
UPPER CASE	ARBUTUS VILLAGE PARK
lower case	arbutus village park
Title case	Arbutus village park
Full Title Case	Arbutus Village Park

Minimum Length

Tests if the number of characters in the value is greater than or equal to the Minimum Length.

All values are evaluated as strings.

Enter an integer.

Example:

If Minimum Length = 4

Bvd: Failed

Blvd: Passed

Boulevard: Passed

Maximum Length

Tests if the number of characters in the value is less than or equal to the Maximum Length.

All values are evaluated as strings.

Enter an integer.

Example:

If Maximum Length = 4

123: Passed

1234: Passed

999999: Failed

Tests if the value may be found in provided list of possible values and ranges.

Enter any combination of comma-separated strings, numeric values, and/or ranges (in the form of x-y).

Valid configuration examples:

1,10,100

1-99

cat

cat,dog,cats and dogs

dogs,1-9,7

String ranges (for example, a-d) can be specified. To test for values that contain a hyphen, enclose the value in quotation marks: "LL-27","LL-83".

To test for values that contain either single (') or double (") quotes, enclose the value in the opposing quotes: "Duncan's Lake" or 'Say "Hello"'.

Encodable In

Tests if the value is encodable in the specified encoding without data loss.

Select from a list of standard encodings.

Sample encodings:

Unicode 32-bit(utf-32)
Windows Cyrillic (windows-12510
EBCDIC US (ibm037)

Not Null

Tests that the attribute exists on the feature, and is not null.

Unique

Tests if a value is unique (only used once) within the set of features.

The first occurrence of a value will Pass, and any subsequent occurrences of that value will fail.

Has a Value

Tests that the attribute has a value, and is not null, missing, or empty.

Contains Regex

Tests that the value contains a string that matches a pattern described by a Regular Expression.

Enter a Regular Expression.

The Regular Expression Editor is available via the ellipsis (...) button, and may be used to construct and test expressions.

The regex to test may represent a string to be found anywhere within the value, or may represent the entire value (by creating a regex long enough to represent the extent of the desired value).

Example:

If regex is \d

cats: Failed

9: Passed

cats82: Passed

Examples

Example: Validating attributes

In this example, we have a spreadsheet of food cart vendors to test for data quality.

The features are routed into an AttributeValidator.

In the parameters dialog, we construct three tests to perform:

Has a Value: All attributes are tested for the existence of any value, which will identify any missing data.
In: The DESCRIPTION attribute is tested to see if its values are in a list of valid options. The list is typed in, with items separated by commas. Items that fail this test may have the wrong information, or data entry errors such as the wrong case or spelling.
Type: The LAT and LON attributes are tested to see if they contain floating-point numbers. As these contain the location of the vendors, items that fail this test may have invalid coordinates.

Features that fail any of the tests are output via the Failed port. A new attribute - _fme_validation_message - has been added, and contains details of the first test failed for each feature. Note that the tests are applied in the order they appear in the Validation Rule table.

A new list attribute has also been added (which is not visible in the Table view) - _fme_validation_message_list{}. All tests failed are added to the list attribute.

Usage Notes

Output feature order may be controlled with the Advanced > Preserve Feature Order parameter.

Configuration

Input Ports

Output Ports

Parameters

Validation Rules

See Creating Validation Rules above for further detail.

Attributes to Validate

Select the attribute(s) to be tested.

Validation Rule

Select the type of test to be performed. Options include:

Type	Boolean Double Integer Numeric Alphanumeric String XML JSON Date Datetime Datetime with Offset Time Time with Offset
In Range
Case	UPPER CASE lower case Title case Full Title Case
Minimum Length
Maximum Length
In
Encodable In
Not Null
Unique
Has a Value
Contains Regex

Rule Configuration

Enter any supplementary configuration information for the test selected.

Advanced

Preserve Feature Order

This parameter controls the order in which features exit a transformer.

When a transformer has more than one output port, features usually exit one port at a time. At times, it may be useful to keep the order that features arrived in, switching from port to port as necessary. This allows feature order to be preserved, though at a potential cost in processing efficiency.

Select a method for feature ordering.

Per Output Port (Default)

Only preserve the input order of features as they occur within the group of features exiting a given output port.

All features exiting an output port retain their ordering relative to each other (within the group), but not relative to features exiting other output ports.

This option is generally the most efficient, where large chunks of features will exit an output port together (taking advantage of bulk mode).

As features exiting different output ports may not be strictly output in the order they arrived, output ordering may be unpredictable.

Across Output Ports

Strictly preserve the input order of features, regardless of which output port they exit. Features will be output singly in the same order they arrived, switching from port to port as necessary. This option is generally less efficient as the processing gains of bulk mode are less likely to apply - however, feature order is predictable.

Editing Transformer Parameters

Transformer parameters can be set by directly entering values, using expressions, or referencing other elements in the workspace such as attribute values or user parameters. Various editors and context menus are available to assist. To see what is available, click beside the applicable parameter.

How to Set Parameter Values

Defining Values

There are several ways to define a value for use in a Transformer. The simplest is to simply type in a value or string, which can include functions of various types such as attribute references, math and string functions, and workspace parameters.

Using the Text Editor

The Text Editor provides a convenient way to construct text strings (including regular expressions) from various data sources, such as attributes, parameters, and constants, where the result is used directly inside a parameter.

Text Editor

Using the Arithmetic Editor

The Arithmetic Editor provides a convenient way to construct math expressions from various data sources, such as attributes, parameters, and feature functions, where the result is used directly inside a parameter.

Arithmetic Editor

Conditional Values

Set values depending on one or more test conditions that either pass or fail.

Parameter Condition Definition Dialog

Content

Expressions and strings can include a number of functions, characters, parameters, and more.

When setting values - whether entered directly in a parameter or constructed using one of the editors - strings and expressions containing String, Math, Date/Time or FME Feature Functions will have those functions evaluated. Therefore, the names of these functions (in the form @<function_name>) should not be used as literal string values.

Content Types

String Functions	These functions manipulate and format strings.
Special Characters	A set of control characters is available in the Text Editor.
Math Functions	Math functions are available in both editors.
Date/Time Functions	Date and time functions are available in the Text Editor.
Math Operators	These operators are available in the Arithmetic Editor.
FME Feature Functions	These return primarily feature-specific values.
FME Parameters	FME and workspace-specific parameters may be used.
Creating and Modifying User Parameters	Create your own editable parameters.

Dialog Options - Tables

Table Tools

Transformers with table-style parameters have additional tools for populating and manipulating values.

Row Reordering

Enabled once you have clicked on a row item. Choices include:

Add a row
Remove a row
Move current row up one
Move current row down one
Move current row to top
Move current row to bottom

Cut, Copy, and Paste

Enabled once you have clicked on a row item. Choices include:

Cut a row - delete and copy to clipboard
Copy a row to the clipboard
Paste a row from the clipboard

Cut, copy, and paste may be used within a transformer, or between transformers.

Filter

Start typing a string, and the matrix will only display rows matching those characters. Searches all columns. This only affects the display of attributes within the transformer - it does not alter which attributes are output.

Import

Import populates the table with a set of new attributes read from a dataset. Specific application varies between transformers.

Reset/Refresh

Generally resets the table to its initial state, and may provide additional options to remove invalid entries. Behavior varies between transformers.

Note: Not all tools are available in all transformers.

For more information, see Transformer Parameter Menu Options.

Reference

Processing Behavior	Feature-Based
Feature Holding	No
Dependencies	None
Aliases	AttributeClassifier, StringClassifier
History	This transformer replaced the AttributeClassifier transformer.

FME Community

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Examples may contain information licensed under the Open Government Licence – Vancouver, Open Government Licence - British Columbia, and/or Open Government Licence – Canada.