[ogsa-wg] Grid Command Line interfaces

[Andre Merzky]

Quoting [Steven Newhouse] (Jun 04 2008):
> 
> > is a SAGA command line binding something you would
> > conider worth pursuing?  We actually started to do
> > something like that, in a pet project...
> 
> Do you mean the ability to implement any defined command
> line interface using the SAGA APIs? (i.e. internal to the
> command) Or To define a set of command line tools to cover
> elements of the SAGA API?

The latter.  For example, for the SAGA call

  class saga::filesystem::file 
  {
    void copy (saga::url src, saga::url tgt, it flags);
  }

define the command line tool

  saga_file_copy [flags] <src> <tgt>

      flags:
        session related flags
          -s|--session <s>   run command in session s
          -c|--context <c>   use context c
    
        operational flags
          -a|--async=<Sync|Async|Task> 
                              use async mode Sync, Async or Task
                              default is Sync
        call specific flags
          -r|--recursive  copy recursively
          -o|--overwrite  overwrite target if exists
          ...

So, the command line tools would basically reflect what we
define in the SAGA API spec, with a set of flags which are
consistent for all command line tools such defined.


A session could look like:

  # saga_create_context --name=my_context --type=UserPass --user=anon
  <prompts for password>

  # saga_create_session --name my_session --add_context=my_context

  # /bin/date | saga_file_cat --session=my_session --write gsiftp://localhost/tmp/in.dat

  # saga_file_copy --session=my_session gsiftp://localhost/tmp/in.dat gsiftp://remotehost/tmp/out.dat

  # saga_file_cat  --session=my_session gsiftp://remotehost/tmp/out.dat
  Wed Jun  4 14:43:27 CEST 2008


or, with some default assumptions of course (default session
and context):


  # /bin/date | saga_file_cat --write gsiftp://localhost/tmp/in.dat
  # saga_file_copy gsiftp://localhost/tmp/in.dat gsiftp://remotehost/tmp/out.dat
  # saga_file_cat  gsiftp://remotehost/tmp/out.dat
  Wed Jun  4 14:43:27 CEST 2008


Best, Andre.

PS.: As for option (a) of yours: yes, that would be trivial to
     implement in SAGA :-)  Well, at least it would be easy (one
     needs to add some magick for state management, to keep track
     of async ops and security credentials between separate calls 
     to different tools.

> Steven



-- 
Nothing is ever easy.