GetFeatureInfo

GetFeatureInfo provides feature information by identifying a point on a map based on its pixel location. The GetFeatureInfo request embeds many of the parameters required in the GetMap request along with parameters specific to querying layers.

In the OGC WMS specification, GetFeatureInfo is optional. The specification leaves the response format open, and there is no standard. ESRI uses stylesheets that are described in the section Output formats.

The following parameters can be appended to the GetFeatureInfo request. See the WMS Specification documentation for detailed descriptions of each parameter. The parameters listed with an asterix (*) are also required in a GetMap request.

Request Parameter Required/Optional Description
REQUEST=GetFeatureInfo R Request name.
VERSION=version* R Request version. Valid values are 1.0.0, 1.1.0, or 1.1.1.
SRS=EPSG:id_code* R Spatial Reference System (SRS) identifier the map is returned in. Identifiers correspond to coordinate system ID codes found in the ArcXML Programmerís Reference Guide.
BBOX=minx,miny,maxx,maxy* R Bounding box corners (lower left, upper right). Values must be in the units of the specified SRS.
WIDTH=output_width* R Width in pixels of resulting map image.
HEIGHT=output_height* R Height in pixels of resulting map image.
QUERY_LAYERS=layer_list R Comma-separated list of one or more map layers to be queried. Values in the list correspond to the layer <name> values in the Capabilities file. This name corresponds to the layer id in ArcXML.
X=pixel_column R X coordinate in pixels of feature measured from upper left corner of the map.
Y=pixel_row R Y coordinate in pixels of feature measured from upper left corner of the map.
INFO_FORMAT=output_format O Return format of feature information. The default value is application/vnd.ogc.wms_xml. Other options are text/xml, text/html, and text/plain.
FEATURE_COUNT=number O Number of features per layer allowed. The default is 1.
EXCEPTIONS=exception_format O The format in which exceptions are reported. The default and only supported value is application/vnd.ogc.se_xml.
SERVICENAME=service_name
(vendor specific)
O By default, the capabilities of the default WMS service is queried. If you want to use a non-default service, the service name must be included in the URL.

Examples

Example 1: Using the minimum amount of parameters

This example shows the minimum number of parameters needed to make a successful GetFeatureInfo request. This example uses the default WMS service, which is the service name you selected in the WMS Connector Administrator. For more information about the Administrator page, see Using the WMS Connector Administrator.

http://<hostname>/<deploy_name>/com.esri.wms.Esrimap?SERVICE=WMS&VERSION=1.1.1&REQUEST=GetFeatureInfo&SRS=EPSG:4326&BBOX=-117,38,-90,49&WIDTH=600&HEIGHT=400&QUERY_LAYERS=States&X=200&Y=150&

where


Example 2: Specifying a nondefault WMS service

In this next example, a non-default WMS service is specified.

http://<hostname>/<deploy_name>/com.esri.wms.Esrimap?VERSION=1.1.1&REQUEST=GetFeatureInfo&SRS=EPSG:4326&BBOX=-117,38,-90,49&WIDTH=600&HEIGHT=400&QUERY_LAYERS=States&X=200&Y=150&SERVICENAME=myService&

where

A second way to specify a non-default WMS service does not use the SERVICENAME parameter.

http://<hostname>/<deploy_name>/com.esri.wms.Esrimap/myService?VERSION=1.1.1&REQUEST=GetFeatureInfo&SRS=EPSG:4326&BBOX=-117,38,-90,49&WIDTH=600&HEIGHT=400&QUERY_LAYERS=States&X=200&Y=150&

where


Example 3: Using optional parameters

In the following example, optional parameters are specified. This URL should be all on one line.

http://<hostname>/<deploy_name>/com.esri.wms.Esrimap?SERVICE=WMS&VERSION=1.1.1&REQUEST=GetFeatureInfo&SRS=EPSG:4326&BBOX=-117,38,-90,49&WIDTH=600&HEIGHT=400&QUERY_LAYERS=States&X=200&Y=150&SERVICENAME=myService&
INFO_FORMAT=text/html&EXCEPTIONS=application/vnd.ogc.se_xml&FEATURE_COUNT=5&

where

Note: Hard returns added to URLs for readability

Output formats

The WMS specification does not specify an output format for a response. ESRI has provided four XSL stylesheets located in the expanded WAR file's WEB-INF directory.

The location of the expanded WAR file directory varies depending on the servlet engine you are using. However, the structure of the expanded WAR file is the always the same.

<Application Name>
      |__WAR
         |__WEB_INF
            |__classes
               |__wms
                  |__stylesheets
                     |__wms_featureinfo.xsl
                     |__wms_featureinfo_html.xsl
                     |__wms_featureinfo_plain.xsl
                     |__wms_featureinfo_xml.xsl

where

Each of the stylesheets provides a different output format.

Application/vnd.ogc.wms_xml output format

The application/vnd.ogc.wms_xml format is an XML format, and the referenced XSL stylesheet is wms_featureinfo.xsl. A typical response looks like the following. The fields are listed alphabetically inside a FeatureInfoResponse tag. A separate FIELDS tag exists for each returned feature for each layer.

<?xml version="1.0" encoding="UTF-8"?>
<FeatureInfoResponse>
<FIELDS FEMALES="226581" MALES="227007" POP1999="482025" STATE_NAME="Wyoming" _ID_="6" _SHAPE_="[Geometry]" _LAYERID_="0"/>
</FeatureInfoResponse>

Text/xml output format

The text/xml format is the same XML format as vnd.ogc.wms_xml. However, this format displays correctly in Internet Explorer and Netscape. The referenced XSL stylesheet is wsm_featureinfo_xml.xsl.

Text/html output format

The text/html format displays the data in an HTML table.

FEMALES MALES POP1999 STATE_NAME _ID_ _SHAPE_ _LAYERID_
226581 227007 482025 Wyoming 6 [Geometry] 0

The look and feel can be changed by modifying the XSL stylesheet wms_featureinfo_html.xsl. Some common changes are to modify the table color or format.

  1. Open wms_featureinfo_html.xsl in a text or XML editor.
  2. To change the colors, search for the following
    • th bgcolor="#006699" for the table header background color. Change "#006699" to the new color of your choice.
    • font color="#FFFFFF" for the font color. Change "#FFFFFF" to the new color of your choice.
    • td bgcolor="#99CCFF" for the table row background color. Change "#99CCFF" to the new color of your choice.
  3. To change the HTML table format, search for <table. You can add additional HTML table attributes as desired.

Text/plain output format

The text/plain format returns data in a text string. Each field is delimited by a space by default. If a field value contains a space and is surrounded by double quotes (").

"FEMALES" "MALES" "POP1999" "STATE_NAME" "_ID_" " _SHAPE_" "_LAYERID_"
"226581" "227007" "482025" "Wyoming" "6" "[Geometry]" "0"

The attribute delimiter can be changed in the XSL stylesheet named wms_featureinfo_plain.xsl.

  1. Open wms_featureinfo_plain.xsl in a text or XML editor.
  2. Search for the following string:
    <xsl:value-of select="x"/>
  3. The value immediately following this string is the delimiter. Change this to the delimiter of your choice.

Errors

The GetFeatureInfo response returns an XML structure containing error information if the WMS service detected an error.

<?xml version="1.0" encoding="UTF-8" standalone="yes" ?>
<ServiceExceptionReport version="1.1.1">
<ServiceException>
Invalid query_layers value
</ServiceException>
</ServiceExceptionReport>

You will always receive an error if the HTTP request is improperly formatted or a required parameter is missing. Common error messages are:

Problem Error message
REQUEST missing Missing mandatory REQUEST parameter. Possibilities are {capabilities|GetCapabilities|map|GetMap|feature_info|GetFeatureInfo}
VERSION missing Missing VERSION | WMTVER parameter
SRS missing Missing SRS parameter or value
BBOX missing or one of the values is missing Invalid BBOX value
Invalid BBOX value Invalid BBOX NumberFormatException: For input string: "<value>"
WIDTH missing Invalid WIDTH NumberFormatException : null
Invalid WIDTH value Invalid WIDTH NumberFormatException : For input string: <value>
HEIGHT missing Invalid HEIGHT NumberFormatException : null
Invalid HEIGHT value Invalid HEIGHT NumberFormatException : For input string: <value>
QUERY_LAYERS missing Missing QUERY_LAYERS parameter or value
Invalid query layer name GetFeatureInfo Error: [ERR0706] Layer with ID {id} not found.
X (pixel_column) missing Invalid 'X' value, NumberFormatException : null
Invalid X (pixel_column) value Invalid 'X' value, NumberFormatException : For input string: <value>
Y (pixel_column) missing Invalid 'Y' value, NumberFormatException : null
Invalid Y (pixel_column) value Invalid 'Y' value, NumberFormatException : For input string: <value>
Requested service name is not valid Access to the specified service <service_name> is not available

In some cases, an ArcIMS error message is returned. More information on these error messages is available in the Error messages portion of this help system.

Problem ArcIMS Error message
Requested service is not available. The ArcIMS Service may be stopped or busy. Error sending FeatureInfo response. Exception in FeatureInfo reply
Error: [ERR0134] Requested service is not available.