lecture: Geospatial web services using little-known GDAL features and modern Perl middleware
GDAL has a little-known feature vsistdout_redirect, which is a virtual file system driver that can redirect standard output to any GDAL virtual file. This feature is exploited in GDAL 2.1 Perl bindings to make streaming objects possible. Streaming objects are objects, which belong to a class, which implement 'write' and 'close' subroutines. Such objects happen to be important in modern Perl web middleware, code that are based on PSGI - Perl Web Server Gateway Interface Specification. In this talk I will present a suite of new Perl modules, which implement OGC geospatial web services. I have two of these modules already in production use, one for raster tile service and one for feature service. In this talk I will present and discuss how GDAL and Perl have made it easy to develop and extend these services.