[Mobilitydb-dev] Initial MEOS implementation

[Esteban Zimanyi]

Dear Krishna

We were able to finalize a first version of the MEOS library in the
latest commit of the develop branch.
https://github.com/estebanzimanyi/MobilityDB/commits/develop

What is still missing is the timezone management. The reason for this
is that PostgreSQL uses its own version of the standard files for
timezones

$ ls -l /usr/local/pgsql/14/share/timezone
total 244
drwxr-xr-x 2 root root 4096 May 10 20:17 Africa
drwxr-xr-x 6 root root 4096 May 10 20:17 America
drwxr-xr-x 2 root root 4096 May 10 20:17 Antarctica
...

which is different from those of the underlying operating system,
e.g., the files used in Linux

$ ls -l /etc/localtime
lrwxrwxrwx 1 root root 35 Jun 10 08:21 /etc/localtime ->
/usr/share/zoneinfo/Europe/Brussels

Both MySQL and Python use the standard timezone files
https://docs.oracle.com/cd/E17952_01/mysql-8.0-en/time-zone-support.html
https://docs.python.org/3/library/zoneinfo.html

Our current approach in MEOS is to use the files of the operating
systems. We will start this work from now on.

We have also started writing a wiki page about the architecture
enabling us to generate with the same codebase both MobilityDB and
MEOS libraries.
https://github.com/MobilityDB/MobilityDB/wiki/Building-MobilityDB-and-MEOS

However, all the documentation of the MEOS library still needs to be
written, as marked in the disclaimers of the web pages
https://libmeos.org/
We will work on it in the forthcoming weeks.

The MobilityDB code has been thoroughly improved and tested, but the
MEOS library is NOT yet ready, it is this commit that enables us to
start working on it.

We would appreciate any technical feedback you may have about this architecture.

Best regards

Esteban