prompt: We are currently solving the following issue within our repository. Here is the issue text:
  --- BEGIN ISSUE ---
  [Setup utility] Cannot generate files when database flavors have been switched
  ## Before you open your issue
  - [x] Check if no issue or pull-request for this already exists.
  - [x] Check [documentation](https://mailu.io/master/) and [FAQ](https://mailu.io/master/faq.html). (Tip, use the search function on the documentation page)
  - [x] You understand `Mailu` is made by volunteers in their **free time** — be conscise, civil and accept that delays can occur.
  - [x] The title of the issue should be short and simple. It should contain specific terms related to the actual issue. Be specific while writing the title.
  
  ## Environment & Versions
  ### Environment
   - [x] docker-compose
   - [ ] kubernetes
   - [x] docker swarm
  
  ### Versions
  All versions
  
  ## Description
  In the setup utility when you select a different database flavor and then switch back to SQLite, then you can not generate the files. The reason is that it still expects the fields to be filled of the alternative database flavor you previously selected. 
  When you select an alternative database flavor, the fields (e.g. hostname, database name) are mandatory. These fields are still mandatory when you switch back to SQLlite as database flavor.
  
  As a workaround you can fill in mandatory fields and then switch back to SQLite again. Or you could refresh the page and do not switch from SQLite. 
  
  The problem is in https://github.com/Mailu/Mailu/blob/master/setup/templates/steps/database.html . 
  I didn't check yet how to resolve this.
  
  ## Replication Steps
  1) Go to https://setup.mailu.io/master/ and click next.
  2). Enter a value for main domain server and public hostname.
  3). Select roundcube as webmail.
  4). At the bottom switch to postgresql or mysql as database
  5). Switch back to SQLite as database.
  6). Click Setup mailu. Note that the button does not work.
  
  ## Expected behaviour
  The Setup Mailu button works after following about steps.
  [Setup utility] Cannot generate files when database flavors have been switched
  ## Before you open your issue
  - [x] Check if no issue or pull-request for this already exists.
  - [x] Check [documentation](https://mailu.io/master/) and [FAQ](https://mailu.io/master/faq.html). (Tip, use the search function on the documentation page)
  - [x] You understand `Mailu` is made by volunteers in their **free time** — be conscise, civil and accept that delays can occur.
  - [x] The title of the issue should be short and simple. It should contain specific terms related to the actual issue. Be specific while writing the title.
  
  ## Environment & Versions
  ### Environment
   - [x] docker-compose
   - [ ] kubernetes
   - [x] docker swarm
  
  ### Versions
  All versions
  
  ## Description
  In the setup utility when you select a different database flavor and then switch back to SQLite, then you can not generate the files. The reason is that it still expects the fields to be filled of the alternative database flavor you previously selected. 
  When you select an alternative database flavor, the fields (e.g. hostname, database name) are mandatory. These fields are still mandatory when you switch back to SQLlite as database flavor.
  
  As a workaround you can fill in mandatory fields and then switch back to SQLite again. Or you could refresh the page and do not switch from SQLite. 
  
  The problem is in https://github.com/Mailu/Mailu/blob/master/setup/templates/steps/database.html . 
  I didn't check yet how to resolve this.
  
  ## Replication Steps
  1) Go to https://setup.mailu.io/master/ and click next.
  2). Enter a value for main domain server and public hostname.
  3). Select roundcube as webmail.
  4). At the bottom switch to postgresql or mysql as database
  5). Switch back to SQLite as database.
  6). Click Setup mailu. Note that the button does not work.
  
  ## Expected behaviour
  The Setup Mailu button works after following about steps.
  
  --- END ISSUE ---
  
  Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
  --- BEGIN FILES ---
  Path: `optional/postgresql/start.py`
  Content:
  ```
  1 #!/usr/bin/python3
  2 
  3 import anosql
  4 import psycopg2
  5 import glob
  6 import os
  7 import subprocess
  8 from socrate import conf
  9 
  10 def setup():
  11     conn =  psycopg2.connect(user='postgres')
  12     queries = anosql.load_queries('postgres', '/conf/queries.sql')
  13     # Mailu user
  14     queries.create_mailu_user(conn)
  15     queries.update_pw(conn, pw=os.environ.get("DB_PW"))
  16     # Healthcheck user
  17     queries.create_health_user(conn)
  18     queries.grant_health(conn)
  19     conn.commit()
  20     # create db cannot be atomic. But this script is the only active connection, this is kinda safe.
  21     if not queries.check_db(conn):
  22         conn.set_isolation_level(0)
  23         queries.create_db(conn)
  24         conn.set_isolation_level(1)
  25     conn.close()
  26 
  27 # Check if /data is empty
  28 if not os.listdir("/data"):
  29     os.system("chown -R postgres:postgres /data")
  30     os.system("chmod 0700 /data")
  31     base_backups=sorted(glob.glob("/backup/base-*"))
  32     if base_backups:
  33         # Restore the latest backup
  34         subprocess.call(["tar", "--same-owner", "-zpxf", base_backups[-1] + "/base.tar.gz" , "-C", "/data"])
  35         if os.listdir("/backup/wal_archive"):
  36             with open("/data/recovery.conf", "w") as rec:
  37                 rec.write("restore_command = 'gunzip < /backup/wal_archive/%f > %p'\n")
  38                 rec.write("standby_mode = off\n")
  39             os.system("chown postgres:postgres /data/recovery.conf")
  40     else:
  41         # Bootstrap the database
  42         os.system("sudo -u postgres initdb -D /data")
  43 
  44 # Create backup directory structure, if it does not yet exist
  45 os.system("mkdir -p /backup/wal_archive")
  46 os.system("chown -R postgres:postgres /backup")
  47 
  48 # Render config files
  49 for pg_file in glob.glob("/conf/*.conf"):
  50     conf.jinja(pg_file, os.environ, os.path.join("/data", os.path.basename(pg_file)))
  51 
  52 # (Re)start postgresql locally for DB and user creation
  53 os.system("sudo -u postgres pg_ctl start -D /data -o '-h \"''\" '")
  54 while os.path.isfile("recovery.conf"):
  55     pass
  56 os.system("sudo -u postgres pg_ctl -D /data promote")
  57 setup()
  58 os.system("sudo -u postgres pg_ctl stop -m smart -w -D /data")
  59 
  60 out=open("/proc/1/fd/1", "w")
  61 err=open("/proc/1/fd/2", "w")
  62 # Run the cron deamon
  63 subprocess.Popen(["crond", "-f"], stdout=out, stderr=err)
  64 # Run postgresql service
  65 os.system("sudo -u postgres postgres -D /data -h \*")
  66
  ```
  --- END FILES ---
  
  Please first localize the bug based on the issue statement, and then generate a patch according to the `git diff` format fenced by three backticks.
  
  Here is an example:
  
  ```diff
  diff --git a/examples/server_async.py b/examples/server_async.py
  --- a/examples/server_async.py
  +++ b/examples/server_async.py
  @@ -313,4 +313,4 @@
   
   
   if __name__ == "__main__":
  -    asyncio.run(run_async_server("."), debug=True)
  +    asyncio.run(run_async_server(), debug=True)
  diff --git a/examples/server_sync.py b/examples/server_sync.py
  --- a/examples/server_sync.py
  +++ b/examples/server_sync.py
  @@ -313,5 +313,5 @@
   
   
   if __name__ == "__main__":
  -    server = run_sync_server(".")
  +    server = run_sync_server()
       server.shutdown()
  
  ```
  
golden_diff: diff --git a/optional/postgresql/start.py b/optional/postgresql/start.py
  deleted file mode 100755
  --- a/optional/postgresql/start.py
  +++ /dev/null
  @@ -1,65 +0,0 @@
  -#!/usr/bin/python3
  -
  -import anosql
  -import psycopg2
  -import glob
  -import os
  -import subprocess
  -from socrate import conf
  -
  -def setup():
  -    conn =  psycopg2.connect(user='postgres')
  -    queries = anosql.load_queries('postgres', '/conf/queries.sql')
  -    # Mailu user
  -    queries.create_mailu_user(conn)
  -    queries.update_pw(conn, pw=os.environ.get("DB_PW"))
  -    # Healthcheck user
  -    queries.create_health_user(conn)
  -    queries.grant_health(conn)
  -    conn.commit()
  -    # create db cannot be atomic. But this script is the only active connection, this is kinda safe.
  -    if not queries.check_db(conn):
  -        conn.set_isolation_level(0)
  -        queries.create_db(conn)
  -        conn.set_isolation_level(1)
  -    conn.close()
  -
  -# Check if /data is empty
  -if not os.listdir("/data"):
  -    os.system("chown -R postgres:postgres /data")
  -    os.system("chmod 0700 /data")
  -    base_backups=sorted(glob.glob("/backup/base-*"))
  -    if base_backups:
  -        # Restore the latest backup
  -        subprocess.call(["tar", "--same-owner", "-zpxf", base_backups[-1] + "/base.tar.gz" , "-C", "/data"])
  -        if os.listdir("/backup/wal_archive"):
  -            with open("/data/recovery.conf", "w") as rec:
  -                rec.write("restore_command = 'gunzip < /backup/wal_archive/%f > %p'\n")
  -                rec.write("standby_mode = off\n")
  -            os.system("chown postgres:postgres /data/recovery.conf")
  -    else:
  -        # Bootstrap the database
  -        os.system("sudo -u postgres initdb -D /data")
  -
  -# Create backup directory structure, if it does not yet exist
  -os.system("mkdir -p /backup/wal_archive")
  -os.system("chown -R postgres:postgres /backup")
  -
  -# Render config files
  -for pg_file in glob.glob("/conf/*.conf"):
  -    conf.jinja(pg_file, os.environ, os.path.join("/data", os.path.basename(pg_file)))
  -
  -# (Re)start postgresql locally for DB and user creation
  -os.system("sudo -u postgres pg_ctl start -D /data -o '-h \"''\" '")
  -while os.path.isfile("recovery.conf"):
  -    pass
  -os.system("sudo -u postgres pg_ctl -D /data promote")
  -setup()
  -os.system("sudo -u postgres pg_ctl stop -m smart -w -D /data")
  -
  -out=open("/proc/1/fd/1", "w")
  -err=open("/proc/1/fd/2", "w")
  -# Run the cron deamon
  -subprocess.Popen(["crond", "-f"], stdout=out, stderr=err)
  -# Run postgresql service
  -os.system("sudo -u postgres postgres -D /data -h \*")
  
verification_info: {"golden_diff": "diff --git a/optional/postgresql/start.py b/optional/postgresql/start.py\ndeleted file mode 100755\n--- a/optional/postgresql/start.py\n+++ /dev/null\n@@ -1,65 +0,0 @@\n-#!/usr/bin/python3\n-\n-import anosql\n-import psycopg2\n-import glob\n-import os\n-import subprocess\n-from socrate import conf\n-\n-def setup():\n-    conn =  psycopg2.connect(user='postgres')\n-    queries = anosql.load_queries('postgres', '/conf/queries.sql')\n-    # Mailu user\n-    queries.create_mailu_user(conn)\n-    queries.update_pw(conn, pw=os.environ.get(\"DB_PW\"))\n-    # Healthcheck user\n-    queries.create_health_user(conn)\n-    queries.grant_health(conn)\n-    conn.commit()\n-    # create db cannot be atomic. But this script is the only active connection, this is kinda safe.\n-    if not queries.check_db(conn):\n-        conn.set_isolation_level(0)\n-        queries.create_db(conn)\n-        conn.set_isolation_level(1)\n-    conn.close()\n-\n-# Check if /data is empty\n-if not os.listdir(\"/data\"):\n-    os.system(\"chown -R postgres:postgres /data\")\n-    os.system(\"chmod 0700 /data\")\n-    base_backups=sorted(glob.glob(\"/backup/base-*\"))\n-    if base_backups:\n-        # Restore the latest backup\n-        subprocess.call([\"tar\", \"--same-owner\", \"-zpxf\", base_backups[-1] + \"/base.tar.gz\" , \"-C\", \"/data\"])\n-        if os.listdir(\"/backup/wal_archive\"):\n-            with open(\"/data/recovery.conf\", \"w\") as rec:\n-                rec.write(\"restore_command = 'gunzip < /backup/wal_archive/%f > %p'\\n\")\n-                rec.write(\"standby_mode = off\\n\")\n-            os.system(\"chown postgres:postgres /data/recovery.conf\")\n-    else:\n-        # Bootstrap the database\n-        os.system(\"sudo -u postgres initdb -D /data\")\n-\n-# Create backup directory structure, if it does not yet exist\n-os.system(\"mkdir -p /backup/wal_archive\")\n-os.system(\"chown -R postgres:postgres /backup\")\n-\n-# Render config files\n-for pg_file in glob.glob(\"/conf/*.conf\"):\n-    conf.jinja(pg_file, os.environ, os.path.join(\"/data\", os.path.basename(pg_file)))\n-\n-# (Re)start postgresql locally for DB and user creation\n-os.system(\"sudo -u postgres pg_ctl start -D /data -o '-h \\\"''\\\" '\")\n-while os.path.isfile(\"recovery.conf\"):\n-    pass\n-os.system(\"sudo -u postgres pg_ctl -D /data promote\")\n-setup()\n-os.system(\"sudo -u postgres pg_ctl stop -m smart -w -D /data\")\n-\n-out=open(\"/proc/1/fd/1\", \"w\")\n-err=open(\"/proc/1/fd/2\", \"w\")\n-# Run the cron deamon\n-subprocess.Popen([\"crond\", \"-f\"], stdout=out, stderr=err)\n-# Run postgresql service\n-os.system(\"sudo -u postgres postgres -D /data -h \\*\")\n", "issue": "[Setup utility] Cannot generate files when database flavors have been switched\n## Before you open your issue\r\n- [x] Check if no issue or pull-request for this already exists.\r\n- [x] Check [documentation](https://mailu.io/master/) and [FAQ](https://mailu.io/master/faq.html). (Tip, use the search function on the documentation page)\r\n- [x] You understand `Mailu` is made by volunteers in their **free time** \u2014 be conscise, civil and accept that delays can occur.\r\n- [x] The title of the issue should be short and simple. It should contain specific terms related to the actual issue. Be specific while writing the title.\r\n\r\n## Environment & Versions\r\n### Environment\r\n - [x] docker-compose\r\n - [ ] kubernetes\r\n - [x] docker swarm\r\n\r\n### Versions\r\nAll versions\r\n\r\n## Description\r\nIn the setup utility when you select a different database flavor and then switch back to SQLite, then you can not generate the files. The reason is that it still expects the fields to be filled of the alternative database flavor you previously selected. \r\nWhen you select an alternative database flavor, the fields (e.g. hostname, database name) are mandatory. These fields are still mandatory when you switch back to SQLlite as database flavor.\r\n\r\nAs a workaround you can fill in mandatory fields and then switch back to SQLite again. Or you could refresh the page and do not switch from SQLite. \r\n\r\nThe problem is in https://github.com/Mailu/Mailu/blob/master/setup/templates/steps/database.html . \r\nI didn't check yet how to resolve this.\r\n\r\n## Replication Steps\r\n1) Go to https://setup.mailu.io/master/ and click next.\r\n2). Enter a value for main domain server and public hostname.\r\n3). Select roundcube as webmail.\r\n4). At the bottom switch to postgresql or mysql as database\r\n5). Switch back to SQLite as database.\r\n6). Click Setup mailu. Note that the button does not work.\r\n\r\n## Expected behaviour\r\nThe Setup Mailu button works after following about steps.\n[Setup utility] Cannot generate files when database flavors have been switched\n## Before you open your issue\r\n- [x] Check if no issue or pull-request for this already exists.\r\n- [x] Check [documentation](https://mailu.io/master/) and [FAQ](https://mailu.io/master/faq.html). (Tip, use the search function on the documentation page)\r\n- [x] You understand `Mailu` is made by volunteers in their **free time** \u2014 be conscise, civil and accept that delays can occur.\r\n- [x] The title of the issue should be short and simple. It should contain specific terms related to the actual issue. Be specific while writing the title.\r\n\r\n## Environment & Versions\r\n### Environment\r\n - [x] docker-compose\r\n - [ ] kubernetes\r\n - [x] docker swarm\r\n\r\n### Versions\r\nAll versions\r\n\r\n## Description\r\nIn the setup utility when you select a different database flavor and then switch back to SQLite, then you can not generate the files. The reason is that it still expects the fields to be filled of the alternative database flavor you previously selected. \r\nWhen you select an alternative database flavor, the fields (e.g. hostname, database name) are mandatory. These fields are still mandatory when you switch back to SQLlite as database flavor.\r\n\r\nAs a workaround you can fill in mandatory fields and then switch back to SQLite again. Or you could refresh the page and do not switch from SQLite. \r\n\r\nThe problem is in https://github.com/Mailu/Mailu/blob/master/setup/templates/steps/database.html . \r\nI didn't check yet how to resolve this.\r\n\r\n## Replication Steps\r\n1) Go to https://setup.mailu.io/master/ and click next.\r\n2). Enter a value for main domain server and public hostname.\r\n3). Select roundcube as webmail.\r\n4). At the bottom switch to postgresql or mysql as database\r\n5). Switch back to SQLite as database.\r\n6). Click Setup mailu. Note that the button does not work.\r\n\r\n## Expected behaviour\r\nThe Setup Mailu button works after following about steps.\n", "before_files": [{"content": "#!/usr/bin/python3\n\nimport anosql\nimport psycopg2\nimport glob\nimport os\nimport subprocess\nfrom socrate import conf\n\ndef setup():\n    conn =  psycopg2.connect(user='postgres')\n    queries = anosql.load_queries('postgres', '/conf/queries.sql')\n    # Mailu user\n    queries.create_mailu_user(conn)\n    queries.update_pw(conn, pw=os.environ.get(\"DB_PW\"))\n    # Healthcheck user\n    queries.create_health_user(conn)\n    queries.grant_health(conn)\n    conn.commit()\n    # create db cannot be atomic. But this script is the only active connection, this is kinda safe.\n    if not queries.check_db(conn):\n        conn.set_isolation_level(0)\n        queries.create_db(conn)\n        conn.set_isolation_level(1)\n    conn.close()\n\n# Check if /data is empty\nif not os.listdir(\"/data\"):\n    os.system(\"chown -R postgres:postgres /data\")\n    os.system(\"chmod 0700 /data\")\n    base_backups=sorted(glob.glob(\"/backup/base-*\"))\n    if base_backups:\n        # Restore the latest backup\n        subprocess.call([\"tar\", \"--same-owner\", \"-zpxf\", base_backups[-1] + \"/base.tar.gz\" , \"-C\", \"/data\"])\n        if os.listdir(\"/backup/wal_archive\"):\n            with open(\"/data/recovery.conf\", \"w\") as rec:\n                rec.write(\"restore_command = 'gunzip < /backup/wal_archive/%f > %p'\\n\")\n                rec.write(\"standby_mode = off\\n\")\n            os.system(\"chown postgres:postgres /data/recovery.conf\")\n    else:\n        # Bootstrap the database\n        os.system(\"sudo -u postgres initdb -D /data\")\n\n# Create backup directory structure, if it does not yet exist\nos.system(\"mkdir -p /backup/wal_archive\")\nos.system(\"chown -R postgres:postgres /backup\")\n\n# Render config files\nfor pg_file in glob.glob(\"/conf/*.conf\"):\n    conf.jinja(pg_file, os.environ, os.path.join(\"/data\", os.path.basename(pg_file)))\n\n# (Re)start postgresql locally for DB and user creation\nos.system(\"sudo -u postgres pg_ctl start -D /data -o '-h \\\"''\\\" '\")\nwhile os.path.isfile(\"recovery.conf\"):\n    pass\nos.system(\"sudo -u postgres pg_ctl -D /data promote\")\nsetup()\nos.system(\"sudo -u postgres pg_ctl stop -m smart -w -D /data\")\n\nout=open(\"/proc/1/fd/1\", \"w\")\nerr=open(\"/proc/1/fd/2\", \"w\")\n# Run the cron deamon\nsubprocess.Popen([\"crond\", \"-f\"], stdout=out, stderr=err)\n# Run postgresql service\nos.system(\"sudo -u postgres postgres -D /data -h \\*\")\n", "path": "optional/postgresql/start.py"}], "after_files": [{"content": null, "path": "optional/postgresql/start.py"}]}