core: get rid of `pickle`: Use of `pickle` to serialise data was a technical legacy that was causing trouble to store in database, to update (if a class was serialised, a change could break update), and to security (pickle can lead to code execution). This patch remove all use of Pickle in favour in JSON, notably: - for caching data, a Pydantic model is now used instead - for SQLAlchemy model, the LegacyPickle is replaced by JSON serialisation - in XEP-0373 a class `PublicKeyMetadata` was serialised. New method `from_dict` and `to_dict` method have been implemented to do serialisation. - new methods to (de)serialise data can now be specified with Identity data types. It is notably used to (de)serialise `path` of avatars. A migration script has been created to convert data (for upgrade or downgrade), with special care for XEP-0373 case. Depending of size of database, this migration script can be long to run. rel 443

#!/bin/bash

# we first need to wait for PostgreSQL
# cf. https://stackoverflow.com/a/39028690 (thanks!)

RETRIES=5

until psql -c "select 1" > /dev/null 2>&1 || [ $RETRIES -eq 0 ]; do
  echo "Waiting for postgres server, $((RETRIES--)) remaining attempts…"
  sleep 1
done

ori_dir=${PWD}
cd /src/sat_pubsub/db

# PG should be OK, we now initialize the database. If it's already done, it will fail
# with exit code 3
psql -v ON_ERROR_STOP=1 pubsub < pubsub.sql 2>/dev/null
case $? in
    0) printf "database initialized\n" ;;
    3) printf "database already exists\n" ;;
    *) printf "can't initialize database, please check PostgreSQL container parameters\n" >&2
       exit 1
       ;;
esac

cd $ori_dir

exec /home/libervia/libervia_env/bin/twistd -n libervia-pubsub "$@"