Map Engine WMS

The minimum setup required for a WMS map engine is the capabilities URL for the service.

Optionally you can specify the format of the image generated (gif, jpeg, png, etc.) if the background of the image should be transparent or not, and if not, the colour of the background.
You are also able to change the colours or styling Weave uses to colour selections.

A WMS Tester tool is available from here. It can help resolve issues with WMS servers.

Namespace

urn:com.cohga.server.map.wms#1.0

Tags

mapengine

Properties

Name

Type

Required

Default

Description

Name

Type

Required

Default

Description

id

string

yes



Unique identifier

url

string

yes



The capabilities URL for the WMS service. You should not include the SERVICE, REQUEST or VERSION parameters in the URL, just use the base URL, these parameters will be added automatically based on the type of request that is being made.

Note: WMS version 1.3.0 may be forced on by including the URL VERSION parameter, however, this is not recommended and Weave will use WMS version 1.1.1 by default.

format

string

no

first format reported by map engine

Default format that the map engine will request from the WMS server if one is not specified.

transparent

boolean

no

false

Determines if the areas of the image not covered by spatial data are rendered as transparent or as a solid colour (as set by the background property). Enabling transparency requires an image format that supports it (jpeg and png24 do not).

background

integer

no

white

The RGB value for the image background if transparency is not enabled

username

string

no



A username for connecting to the server.

password

string

no



A password for connecting to the server. This should be encrypted using 'encrypt' at the osgi prompt.

qgis

boolean

no



Force the map engine to be treated as though it were QGIS. Weave will try to determine if the underlying WMS service is provided by QGIS and perform additional optimisations and expose additional capabilities if it is.

Sometimes Weave might not be able to determine this correctly, in which case you can set this property to true in the configuration and the map engine will be treated as though it were being served from QGIS.

If Weave incorrectly determines that the WMS service is QGIS when it is not, then you can set this property to false to disable the additional functionality. (Note: Weave does not automatically identify QGIS 3.4 hence the need to set qgis=true.)

geoserver

boolean

no



Force the map engine to be treated as though it were GeoServer. Weave will try and determine if the underlying WMS service is provided by GeoServer and perform additional optimisations and expose additional capabilities if it is.

Sometimes Weave might not be able to determine this correctly, in which case you can set this property to true in the configuration and the map engine will be treated as though it were being served from GeoServer.

If Weave incorrectly determines that the WMS service is GeoServer when it is not, then you can set this property to false to disable the additional functionality.

arcgis

boolean

no



Force the map engine to be treated as though it were ArcGIS. Weave will try and determine if the underlying WMS service is provided by ArcGIS and perform additional optimisations and expose additional capabilities if it is.

Sometimes Weave might not be able to determine this correctly, in which case you can set this property to true in the configuration and the map engine will be treated as though it were being served from ArcGIS.

If Weave incorrectly determines that the WMS service is ArcGIS when it is not, then you can set this property to false to disable the additional functionality.

arcims

boolean

no



For those still using ArcIMS I'm sure you can figure out what this property does by reading the three properties before this one

disableTests

boolean

no

false

Set to true to disable the background checks to validate WMS connections

testInterval

integer

no

60,000

Milliseconds between tests when the WMS connection is working (minimum 15,000)

testIntervalWhileFailing

integer

no

15,000

Milliseconds between tests when the WMS connection is failing (minimum 5,000)

testFailingDuration

integer

no

300,000

How long before a failing WMS connection is determined to have failed (minimum 60,000)

testIntervalWhenFailed

integer

no

600,000

Milliseconds between tests when the WMS connection has failed (minimum 120,000)

cql

boolean

no

false

Set to true if the map engine supports filtering using CQL. If the map engine is one that is not directly supported by Weave but does support using CQL to filter layers then setting this to true will enable the support for layer filtering using CQL.

cqlparamname

string

no

cql_filter

The name of the parameter to add to the request URL if CQL filtering support was enabled by setting cql to true

cqlseparator

string

no

;

The filter separator to add to the request if CQL filtering support was enabled by setting cql to true

Sub-tags

Name

Type

Cardinality

Description

Name

Type

Cardinality

Description

layers

#layers

0..1

Refine what layers are included in the map description.

sort

#sort

0..1



styles

#style

0..1



crs

#crs

0..n

Refine what CRSs the map engine lists as being supported, as opposed to including all of them (as there might be thousands of CRSs that the WMS server says that it supports).

Without any crs tags a map engine will report all the projections the WMS server says it supports. By adding one or more crs tag you can refine this list so that the map engine only includes those projections that you're actually interested in using (which helps to improve performance). 

tokens

#tokens

0..1

Additional tokens to add to the request. The tokens available are dependent on the WMS server implementation and are generally used to support implementation specific extensions to the WMS specification.

legend

#legend

0..1

Modify the legend. Available from 2.6.9.

layers

Sub-tags

Name

Type

Cardinality

Name

Type

Cardinality

layer

#layer

0..n

remove

#remove

0..1



You should include one remove tag or one or more layer tags, not both.

remove

Sub-tags

Name

Type

Cardinality

Name

Type

Cardinality

layer

#layer

1..n

sort

Properties

Name

Type

Required

Description

Name

Type

Required

Description

method

"firsttolast" or "lasttofirst"

no

Default is firsttolast. It specifies if the layer list specifies layers to be sorted from top to bottom or from bottom to top.

Sub-tags

Name

Type

Cardinality

Name

Type

Cardinality

layer

#layer

2..n

layer

Content

The id of the layer

You do not need to include all layers in the layer list, only those you want moved, which is where the method property comes in. If you want to list a handful of layers to draw on top then just list them and use firsttolast (or don't set the method). If you only want to list a handful of layers to move to the bottom on the map then just list them and use lasttofirst.

styles

Properties

None.

Sub-tags

Name

Type

Cardinality

Name

Type

Cardinality

style

#style

1..n

style

Properties

Name

Type

Required

Description

Name

Type

Required

Description

layer

string

yes

The id of the layer, from the map engine, to override the style for

name

string

yes

The name of the style to use

crs

Properties

Name

Type

Required

Description

Name

Type

Required

Description

force

boolean

no

Ensure the CRS is added to the list of available CRSs even if the underlying server doesn't indicate that it supports the EPSG code

Content

The EPSG code of the coordinate reference system to add

tokens

Tokens provide a way for the administrator to include additional parameters in the URL sent to the WMS server

Properties

Name

Type

Required

Default

Description

Name

Type

Required

Default

Description

tokenJoinDelimiter

string

no

;

value to use to join multiple tokens with the same name, since 2.6.7

Sub-tags

Name

Type

Cardinality

Name

Type

Cardinality

token

#token

1..n

token

Properties

Name

Type

Required

Default

Description

Name

Type

Required

Default

Description

name

string

yes



The name of the token

value

string

yes



The value of the token

legendOnly

boolean

no

false if layer is empty

true if layer is not empty

Should this token only be applied to requests that are generating a legend

layer

string

no



Comma separated list of layer id's for which this token should be included, can be used to further restrict when the token is sent, and allows for different tokens to be sent for different layers. Only applies if legendOnly is true

prefix

string

no



Value to be prepended to the token value, since 2.6.7

infix

string

no

or

Value to be used to join multiple user attributes, since 2.6.7

suffix

string

no



Value to be appended to the token value, since 2.6.7

default

string

no



Value to be used if user attribute substitution does not provide a value, since 2.6.7

legend

Properties

Sub-tags

Name

Type

Cardinality

Name

Type

Cardinality

remove

#remove

0..1

aliases

#aliases

0..1

aliases

List the new labels to be displayed for a layer

Properties

None

Sub-tags



Name

Type

Cardinality

alias

#alias

1..n



Content

None

alias

A single label change for a layer

Properties



Name

Type

Required

Description

id

string

yes

The id of the layer to change. Note if a match is not found for the id the label of the layer will be then be searched for.

label

string

yes

The new label to display



Sub-tags

None

Content

None

Examples

Filtering layers to only include specific layers
<wms:mapengine id="test"> <url>http://server/wms/test</url> <layers> <layer>point1</layer> <layer>point2</layer> <layer>line1</layer> <layer>line2</layer> <layer>polygon1</layer> <layer>polygon2</layer> </layers> </wms:mapengine>



Filtering layers to remove specific layers
<wms:mapengine id="test"> <url>http://server/wms/test</url> <layers> <remove> <layer>point2</layer> <layer>line2</layer> <layer>polygon2</layer> </remove> </layers> </wms:mapengine>



Sorting layers
<wms:mapengine id="test"> <url>http://server/wms/test</url> <sort> <layer>point1</layer> <layer>point2</layer> <layer>line1</layer> <layer>line2</layer> <layer>polygon1</layer> <layer>polygon2</layer> </sort> </wms:mapengine>



Sorting layers by moving one layer to the bottom



Applying styles



Adding authentication



Refine the list of supported CRS's for the map engine



Adding tokens



Editing legend content



As of version 1.3.7 of the WMS bundle, the password can be encrypted using the OSGi encrypt command.

WMS 1.3.0

Don't "upgrade" to WMS 1.3.0 unless you really have to.

Version 2.15.16 of the com.cohga.server.map.wms bundle (released as part of Weave 2.5.21) improves support for WMS 1.3.0 by supporting map services that require their axis order to be swapped.

Weave disables the use of WMS 1.3.0 when communicating with a WMS server unless it's specifically asked to, which can be done by including a VERSION parameters in the map engine url attribute, e.g.

Enabling support for WMS 1.3.0

This is typically all you need to do to enable support for WMS 1.3.0. It is possible that you may be using a coordinate reference system that requires requests sent to the server to reverse the order of x, y coordinates. It is updated 2.14.16 of the Weave WMS map engine bundle that allows you to tell Weave to change the order of the coordinates when sending requests to the server