U.S. Census Bureau TIGER/GML Reader Parameters

A GML instance document specifies the namespace and the location of its application schema through its root element xsi:schemaLocation attribute. This field allows the GML reader to use a different GML schema document from the one specified in the xsi:schemaLocation attribute.

The XML Schema specification states that the xsi:schemaLocation attribute value consists of a set of pairs: The first member of each pair is the namespace for which the second member is the hint describing where to find an appropriate schema document. The presence of this hint does not require the processor to obtain or use the cited schema document, however, the processor is free to use other schemas obtained by other suitable means.

Note: This only takes effect if the target namespace of the dataset is not in the Safe fixed schema namespace http://www.safe.com/xml/schemas/FMEFeatures. The GML2 writer in Fixed Schema Mode writes out documents that belong to that namespace.

Determines whether the reader should validate the specified dataset file.

Specifies how the reader obtains feature types:

• XSD Schema: FME reads feature types from the XSD.
• Dataset Only: FME reads feature types from the dataset.
• Dataset Only with Attributes Merged from XSD: FME reads feature types from the dataset, and includes any attributes in the XSD that are associated with a particular feature type.

This parameter can be used to tell the reader to ignore the schema files that are specified in the xsi:schemaLocation attribute of the root element in the dataset. This is particularly useful if the file locations specified in xsi:schemaLocation are not valid file paths.

Overrides the axis order when reading a coordinate tuple in a GML element.

Valid values:

1,2

2,1

1,2,3

2,1,3

(There is no default value for most GML formats; however, for IndoorGML, there is a default blank value (which is the same as 1,2,3.)

For example, if the srsName in the GML document is set to urn:ogc:def:crs:EPSG:6.6.4326, and you are sure that the coordinate order in the GML document is lon-lat and not lat-lon order, set this parameter to 1,2 so that the reader reads the data in lon-lat order.

This parameter affects the interpretation of the start and end angles for gml:ArcByCenterPoint.

The parameter overrides the default interpretation for the 0 axis location and angle direction regardless of the dataset SRS.

By default, if the SRS axis order is 1,2 or 1,2,3, then the angle direction is assumed to run counterclockwise starting from the horizontal axis. Otherwise, when the x and y axes are flipped, the angles run clockwise starting from the vertical axis.

This parameter controls how segments in a path are joined together when the segments' end points are not connected:

• Inserting New Segment connects the path by inserting a new connecting segment between the original segments.
• Snapping End Points forces the first point of each segment to equal the last point of the previous segment.

Note: For backwards compatibility, Inserting New Segment is assumed when the Enforce Path Continuity By parameter is not present.

This parameter specifies how embedded GML objects (those containing a gml:id), that are not geometries should be mapped.

By default, these embedded objects are mapped into FME attributes.

If the parameter is set to Geometries, the embedded objects are mapped into FME Geometries, and the embedded object properties are loaded into geometric traits. In turn, nested embedded objects are mapped into nested aggregate geometries.

If the parameter is set to Feature Types, the embedded objects will be mapped into separate FME feature types, and these feature types will have an additional gml_parent_id attribute whose value refers back to its parent feature.

Specifies whether the default and optional GML feature properties, name and description, should be read.

This parameter specifies whether the GML geometric properties should be represented as individual, and possibly multiple, geometry columns in FME feature type definitions.

A geometric column in an FME data feature is represented either as a single named geometry, or, if multiple geometry columns are present, as an aggregate geometry with multiple named geometry components. This aggregate geometry will also have its Contains Individual Geometries interpretation flag set.

A new attribute type has also been introduced for specifying the order and/or position of a geometric column in the feature type definition. If an attribute X has its type set to xml_geometry, this attribute X becomes a placeholder in the feature type definition. It is a placeholder because actual data features for the feature type definitions will not have this attribute; instead, the data features will have a geometry named “X”.

The list of whitespace-separated QNames specified in this parameter defines properties that the reader should ignore while processing the GML application schemas.

To ignore property regardless of namespace, simply specify the local-part of the name. For example:

boundedBy name

will ignore all properties whose local name are boundedBy or name, regardless of their namespace.

A prefix in a QName should be present in the parsed XML schemas. If no corresponding URI namespace can be found for a prefix, then the prefix will be discarded. The QName will (as in the unprefixed case) apply to all properties with the same local-part, regardless of namespace.

For example:

gml:boundedBy identifier wrong-prefix:description

If a binding for the gml prefix can be found in the parsed schema, then only boundedBy properties with the same namespace URI as gml will be ignored; otherwise, every boundedBy property regardless of namespace will be ignored.

Every identifier property, regardless of namespace, will be ignored. Every description property regardless of namespace will also be ignored, since the parsed schema will not have a binding for the "wrong-prefix" prefix.

Specifies whether GML properties that are defined as a complex type with complex content (that is, those that have embedded children elements) should be mapped as nested list attributes within FME features.

If the value is set to XML Fragments, then the complex properties with complex content are mapped as XML fragments.

Some complex properties, such as those that are recursively defined, cannot be mapped as nested lists. These complex properties will always be mapped as XML fragments, regardless of the setting for this parameter.

This optional parameter can control the depth of nested list attributes.

When this parameter is selected, the reader, in addition to mapping the GML geometry XML elements into FME geometries, will include these elements in FME attributes as XML fragments in the feature.

The FME geometry attributes are typed as xml_geometry in the feature type definition. In the group Version and XML Namespace Processing below, see the parameter Use Old Reader for GML v3.1.1 and v2.1.2 Documents.

This parameter is useful in the case of a GML geometry reading error, since the XML fragment representing the GML geometry will also be carried along in the same feature as an attribute.

Specifies whether GML properties that are mapped as XML fragments should be converted into XML documents.

The conversion will add missing namespace declarations to the fragments, it will maintain CDATA sections, and it will also prefix an XML header declaration to the fragment. Converting the XML fragments into XML documents allows XML-based parsers, e.g., XSLT and XQuery based processors, to further process the fragments.

This parameter specifies whether GML properties that are mapped as XML fragments should be flattened into nested attributes.

The flattening will only be applied to the data features carrying the XML fragments, hence the new flattened nested attributes will not be reflected in the FME feature type schema definitions.

These options are available for the flattened list attributes:

• Substitute Open List Brace: This directive specifies the character to use as the open brace for the flattened list attributes. The open brace defaults to a curly brace { but any single character is accepted.
• Substitute Close List Brace: This directive specifies the character to use as the close brace for the flattened list attributes. The close brace defaults to a curly brace } but any single character is accepted.
• Substitute Element List Separator: This directive specifies the string to use as the separator for components within the nested attributes. The nested attribute component separator defaults to a period (.) but any single character is accepted.

When selected, this parameter instructs the GML reader to use the older GML v3.1.1 code base to read GML v3.1.1 and v2.1.2 documents.

Note: This parameter is enabled only for GML and WFS readers.

When selected, this parameter disables automatic reader selection/switching.

When the GML reader is reading OS MasterMap or CityGML data, FME analyzes the namespace header for URIs that indicate format, and then passes the data on to that reader. The reader then automatically switches to the OS(GB) MasterMap or CityGML reader.

When selected, this parameter disables XML Namespace processing for the underlying XML parser.

Note that this may cause reading errors if the GML schema and the GML data use different prefixes for the same namespace URI. This parameter may be useful for datasets that are not XML-Namespace-valid.

Use this parameter to expose Format Attributes in Workbench when you create a workspace:

• In a dynamic scenario, it means these attributes can be passed to the output dataset at runtime.
• In a non-dynamic scenario where you have multiple feature types, it is convenient to expose additional attributes using this one parameter. For example, if you have ten feature types and want to expose the same attribute in each one, it is easier to define it once than it is to set each feature type individually in the workspace.

Using the minimum and maximum x and y parameters, define a bounding box that will be used to filter the input features. Only features that intersect with the bounding box are returned.

If all four coordinates of the search envelope are specified as 0, the search envelope will be disabled.

Select this parameter to remove any portions of imported features being read that are outside the Search Envelope.

The illustration below shows the results of the Search Envelope when Clip to Search Envelope is set to No on the left side and Yes on the right side.

• No: Any features that cross the search envelope boundary will be read, including the portion that lies outside of the boundary.
• Yes: Any features that cross the search envelope boundary will be clipped at the boundary, and only the portion that lies inside the boundary will be read. The underlying function for the Clip to Search Envelope function is an intersection; however, when Clip to Search Envelope is set to Yes, a clipping operation is also performed in addition to the intersection.

Specify the authentication method to use when accessing a password-protected server.

• Basic: (default) Basic access authentication is designed to allow a client to provide credentials to a server on the assumption that the connection between them is trusted and secure. Note that any credentials passed from client to server can be easily intercepted through an insecure connection.
• Digest: Digest authentication is one of the agreed-upon methods a web server can use to negotiate credentials, such as username or password, with a user's web browser.
• NTLM: A challenge-response protocol that is used to provide compatibility with versions of Windows earlier than the Windows 2000 operating systems.
• Web Connection: Web connections provide a convenient and secure way to store and reuse previously established connection parameters. See Web Connection below.
• Single Sign-on: FME will use the credentials of the current user to authenticate the HTTP request. This authentication method currently works only on the Windows operating system.

Note: To access datasets using a proxy server, use the Network tools in FME Options. From the Workbench menu, select Tools > FME Options > Network. For more information, see "Network Proxy" in the FME Workbench Help.

Using Web Connections

FME Options: Web Connections