Service Exceptions

According to OGC standards, the server must publish a service exception report when receiving an invalid request. This report is used to describe causes of invalid requests to applications on the client or users. The EXCEPTION parameter in requests represents in which format the client expects to get service exception information.

Software modules instead of implementation process of WMS may occur errors, and thus leads to occurrence of exception information undefined by OGC standards. For example, an error occurs in local computing environment of a WMS server instance (for example, disk space is insufficient), causing that the server cannot handle WMS requests and meanwhile it may publish error information. Or, according to current DCP rules, the server may throw a service exception of a valid type on this DCP when receiving invalid requests (for example, it will send a HTTP 404 status code if prefixes of URL are not correct).