AttributeExposer

Exposes attributes so they can be accessed by downstream transformers and writers.

Typical Uses

Exposing attributes that a workspace is not aware of, such as those created by a SchemaMapper
Exposing normally unexposed fme_ and format-specific attributes for use in the workspace
Exposing attributes in a dynamic translation where source attributes may vary

How does it work?

The AttributeExposer makes unexposed attributes visible in FME Workbench so they can be used elsewhere in the workspace. This transformer is useful if you know features have an attribute, but that attribute is not currently showing as available in your workspace. For example:

FME Attributes (fme_) and more obscure format-specific attributes that are not automatically shown in FME Workbench.
Transformers, such as the SchemaMapper, that dynamically add attributes onto features which FME Workbench is not aware of.

You may enter the attribute names manually, import attributes from any supported source dataset, or import from upstream feature caches. Known attributes (including fme_ and format-specific attributes that are not currently exposed) can be selected from the drop-down menu.

This transformer only exposes the attribute in FME Workbench - it does not ensure that valid attribute names are being exposed. The input features are not modified in any way.

Once the attributes are exposed, they can be accessed elsewhere in the workspace.

Data Type may be optionally set or changed.

Cached Values, Data-Aware Attribute Names and Data Types

If Feature Caching is enabled, valid attribute names from upstream features are shown for attribute selection.

Names and data types may be imported from upstream caches (Import > From Feature Cache...).

Data types may be updated by importing Type only (Import > Types from Feature Cache...).

Examples

Usage Notes

Expose attributes fme_basename and fme_dataset in the reader feature type or the FeatureReader transformer. These attributes are not read unless they are exposed in this manner.

Configuration

Input Ports

Output Ports

Parameters

Attributes to Expose

Attributes

Enter attribute names or choose them from the drop-down list (which provides access to fme_ and format-specific attributes).

The order in which they appear in the list is the order in which they will appear in the Output port of the transformer. Import: Use this to import attribute names from any supported source dataset or upstream feature cache.

Type

(Optional) Specify the attribute's data type. The ellipses button will open an Attribute Type Definition dialog, which can assist with setting Type, Width, and Precision (where necessary).

Type will be populated if Import is used to read a dataset or upstream feature cache.

The attribute is tagged with the specified Type information, but type limitations are not enforced on values at this point, and so mismatches between type and value are possible. Type may be enforced elsewhere in the workspace, such as in writers or by using an AttributeValidator or Tester to check values against type.

Available data types include:

Type	Description	Range (if applicable)	fme_data_type
binary(width)	Binary stores fixed-length binary data. Width defines the size, in bytes.		fme_binary(width)
binarybuffer	Binary buffer stores unbounded (of any size) binary data.		fme_binarybuffer
buffer	Buffer stores unbounded (of any length) character strings.		fme_buffer
char(width)	Character stores fixed-length string data. Width defines the maximum number of characters that can be stored. No padding is required for strings shorter than this width - they may be of any length up to the defined width.		fme_char(width)
date	Date store dates as character strings with the format YYYYMMDD. See Standard FME Date/Time Format.		fme_date
datetime	Date/Time stores dates as character strings with the format [Date][Time], as in: YYYYMMDDHHMMSS.FFF The [Time] component may be formatted with or without fractional seconds, and with or without a UTC offset. See Standard FME Date/Time Format.		fme_datetime
int16	Integer, 16-bit stores signed integers in 2 bytes (16 bits) of space.	-32768 to 32767	fme_int16
int32	Integer, 32-bit stores signed integers in 4 bytes (32 bits) of space.	-2147483648 to 2147483647	fme_int32
int64	Integer, 64-bit stores signed integers in 8 bytes (64 bits) of space.	-9,223,372,036,854,775,808 to 9,223,372,036,854,775,807	fme_int64
int8	Integer, 8-bit stores signed integers in 1 byte (8 bits) of space.	-128 to 127	fme_int8
json	JSON stores unbounded strings formatted in JSON (JavaScript Object Notation).		fme_json
logical	Logical stores TRUE/FALSE data, which may be any of: An integer value of 1 (true) or 0 (false) Any string that begins with "t" or "y" (true), or "f" or "n" (false), or NULL.		fme_boolean
number(width, precision)	Number stores single and double precision floating point values. Width is the total number of characters allocated to the field, including the decimal point. Precision controls the precision of the data and is the number of digits to the right of the decimal.		fme_decimal(width,decimal)
real32	Real32 stores floating-point numeric data that occupies 4 bytes (32 bits) in standard IEEE floating-point format. There is no ability to specify the precision and width of the field.	3.4E +/- 38 (7 digits)	fme_real32
real64	Real64 stores floating-point numeric data that occupies 8 bytes (64 bits) in standard IEEE floating-point format. There is no ability to specify the precision and width of the field.	1.7E +/- 308 (15 digits)	fme_real64
time	Time store times as character strings with the basic format YYYYMMDDHHMMSS.FFF They may be formatted with or without fractional seconds, and with or without a UTC offset. See Standard FME Date/Time Format.		fme_time
uint16	Unsigned integer, 16-bit stores integers greater than or equal to 0 in 2 bytes (16 bits) of space.	0 to 65535	fme_uint16
uint32	Unsigned integer, 32-bit stores integers greater than or equal to 0 in 4 bytes (32 bits) of space.	0 to 4294967295	fme_uint32
uint64	Unsigned integer, 64-bit stores integers greater than or equal to 0 in 8 bytes (64 bits) of space.	0 to 18,446,744,073,709,551,616	fme_uint64
uint8	Unsigned integer, 8-bit stores integers greater than or equal to 0 in 1 byte (8 bits) of space.	0 to 255	fme_uint8
varbinary(width)	Variable-length binary data. Width defines the maximum size, in bytes.		fme_varbinary(width)
varchar(width)	Variable character fields store variable length strings. Width controls the maximum number of characters that can be stored by the field. These are often used to optimize storage.		fme_varchar(width)
xml	XML stores unbounded strings formatted as XML(Extensible Markup Language).		fme_xml

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
History

FME Community

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Search for all results about the AttributeExposer on the FME Community.

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