Developer’s corner


What is the GLU system ?

The goal : to use symbolic service names instead of hardcode URLs.

The URL mechanism is a very simple and powerful tool to “connect” several information services. Generally, to use them, one has to hardcode, in his/her HTML pages or CGI scripts, the hostnames, directories, filenames,(ie URLs)… of other servers. The creation of such links is very easy but what about their maintenance ?! The GLU system (Générateur de Liens Uniformes) gives a global solution to avoid this problem, allowing one to use symbolic names of resources; the URLs will be generated on the fly and always with the most recent definition. These definitions are maintained by the managers of the participating remote services.

The GLU system provides other functionalities like:

  • A general browser of all available resources;
  • An “Intelligent” directory of services which allows the query by data types (AstroGLU/AstroBrowse);
  • Generation of homogeneous HTML code;
  • Management of user and technical documentation;
  • A test sequencer of URLs;
  • Management of mirror sites;
  • Management of URL parameters (see javadoc examples);

Tools and libraries

A SOAP access + The library (all platform): the simplest ways to use the GLU (see javadoc)
The full package (v4.206 - Unix OS): the GLU package is opened for international astronomy partners only. Please, contact CDS before lauching the glu daemon (
The Copyright mention


The Glu Dictionary Browser (for the host
AstroGLU : help to locate the database servers
URLs resolutions: a step by step demonstration in the CDS bibliographic service

Documentation, manuals

glu.txt · Last modified: 2010/04/30 07:40 (external edit)

Thanks for acknowledging the CDS developer’s resources (libraries, source code, etc.)