Spatial filter error (via KVP or JSON binding) #793
Description
Hi,
We're attempting to use the 52deg North Sensor Observation Service APIs provided by DEFRA UK-AIR (i.e. UK government air quality data service).
We're struggling to use the spatial filter feature of the GetObservation endpoint. It's throwing errors that I don't understand. I don't know whether this is user error, a problem with the 52deg North software, or a problem at caused by misconfiguration of the DEFRA system.
I don't know where the best place is to discuss problems with this system so I'll ask here. Please refer me to a more appropriate contact if you can.
I'm calling the API using HTTP requests in Python. I'm happy to share the code, but I'll summarise what I'm doing below.
These are the parameters I'm requesting (shown in JSON format for simplicity of presentation). This is send using the Key-value pair (KVP) binding.
{
"service": "SOS",
"namespaces": "xmlns(om,http://www.opengis.net/om/2.0)",
"spatialFilter": "om:featureOfInterest/*/sams:shape,-1.24,53.46,-1.68,53.24",
"version": "2.0.0",
"request": "GetObservation"
}
<?xml version="1.0" encoding="UTF-8"?>
<ows:ExceptionReport xmlns:ows="http://www.opengis.net/ows/1.1" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="2.0.0" xsi:schemaLocation="http://www.opengis.net/ows/1.1 http://schemas.opengis.net/ows/1.1.0/owsAll.xsd">
<ows:Exception exceptionCode="NoApplicableCode">
<ows:ExceptionText>An error occurred while querying feature identifiers for spatial filter!
[EXEPTION]:
could not extract ResultSet</ows:ExceptionText>
</ows:Exception>
</ows:ExceptionReport>
We also get the same error when using the JSON binding.
The request is defined by OGC SOS 12-006 Requirement 116 -- KVP encoding and I've followed OGC 06-121r3 section 10.2.3 Bounding box KVP encoding:
A WGS 84 bounding box shall be KVP encoded in a corresponding parameter
value list, with the ordered listed values for the quantities:
LowerCorner longitude, in decimal degrees
LowerCorner latitude, in decimal degrees
UpperCorner longitude, in decimal degrees
UpperCorner latitude, in decimal degrees
crs URI = “urn:ogc:def:crs:OGC:1.3:CRS84” (optional)
I'm finding that the provided examples don't work.
Sometimes I see this error:
<html><head><title>Apache Tomcat/7.0.82 - Error report</title><style><!--H1 {font-family:Tahoma,Arial,sans-serif;color:white;background-color:#525D76;font-size:22px;} H2 {font-family:Tahoma,Arial,sans-serif;color:white;background-color:#525D76;font-size:16px;} H3 {font-family:Tahoma,Arial,sans-serif;color:white;background-color:#525D76;font-size:14px;} BODY {font-family:Tahoma,Arial,sans-serif;color:black;background-color:white;} B {font-family:Tahoma,Arial,sans-serif;color:white;background-color:#525D76;} P {font-family:Tahoma,Arial,sans-serif;background:white;color:black;font-size:12px;}A {color : black;}A.name {color : black;}HR {color : #525D76;}--></style> </head><body><h1>HTTP Status 500 - 1</h1><HR size="1" noshade="noshade"><p><b>type</b> Exception report</p><p><b>message</b> <u>1</u></p><p><b>description</b> <u>The server encountered an internal error that prevented it from fulfilling this request.</u></p><p><b>exception</b> <pre>java.lang.ArrayIndexOutOfBoundsException: 1
org.n52.sos.decode.kvp.AbstractKvpDecoder.parseNamespaces(AbstractKvpDecoder.java:357)
org.n52.sos.decode.kvp.v2.GetObservationKvpDecoderv20.decode(GetObservationKvpDecoderv20.java:132)
org.n52.sos.decode.kvp.v2.GetObservationKvpDecoderv20.decode(GetObservationKvpDecoderv20.java:62)
org.n52.sos.binding.KvpBinding.parseRequest(KvpBinding.java:162)
org.n52.sos.binding.KvpBinding.doGetOperation(KvpBinding.java:96)
org.n52.sos.service.SosService.doGet(SosService.java:125)
javax.servlet.http.HttpServlet.service(HttpServlet.java:624)
org.n52.sos.service.ConfiguratedHttpServlet.service(ConfiguratedHttpServlet.java:53)
javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:118)
org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:84)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:113)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:103)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:113)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:54)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:45)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
org.springframework.security.web.authentication.www.BasicAuthenticationFilter.doFilter(BasicAuthenticationFilter.java:150)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:183)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:105)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:87)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
org.springframework.security.web.authentication.www.BasicAuthenticationFilter.doFilter(BasicAuthenticationFilter.java:150)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)
org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:192)
org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:160)
org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:343)
org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:260)
org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)
org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
com.thetransactioncompany.cors.CORSFilter.doFilter(CORSFilter.java:168)
com.thetransactioncompany.cors.CORSFilter.doFilter(CORSFilter.java:233)
</pre></p><p><b>note</b> <u>The full stack trace of the root cause is available in the Apache Tomcat/7.0.82 logs.</u></p><HR size="1" noshade="noshade"><h3>Apache Tomcat/7.0.82</h3></body></html>