You could implement both the data flows (processing shapefiles out from PostGIS, and then into it again) thanks to the power of the ogr2ogr GDAL command.
You have been using this command in different forms and with the most important input parameters in other recipes, so you should now have a good understanding of it.
Here, it is worth mentioning the way OGR lets you export the information related to the current datetime and the original shapefile name to the PostGIS table. Inside the import_shapefiles.sh (Linux, OS X) or the import_shapefiles.bat (Windows) scripts, the core is the line with the ogr2ogr command (here is the Linux version):
ogr2ogr -append -update -f PostgreSQL PG:"dbname='postgis_cookbook' user='me' password='mypassword'" out_shapefiles/$f -nln chp01.hs_uploaded -sql "SELECT acq_date, acq_time, bright_t31, '${f%.*}' AS iso2, '`date`' AS upload_datetime, 'out_shapefiles/$f' as shapefile FROM ${f%.*}"
Thanks to the -sql option, you can specify the two additional fields, getting their values from the system date command and the filename that is being iterated from the script.