Help .. rebuild app failed

2018-04-04 11:11:29.123 UTC [59] postgres@postgres ERROR: database "discourse" already exists

Summary
2018-04-04 11:02:11.971 UTC [47] LOG:  listening on IPv4 address "0.0.0.0", port 5432
2018-04-04 11:02:11.971 UTC [47] LOG:  listening on IPv6 address "::", port 5432
2018-04-04 11:02:11.980 UTC [47] LOG:  listening on Unix socket "/var/run/postgresql/.s.PGSQL.5432"
2018-04-04 11:02:12.018 UTC [50] LOG:  database system was shut down at 2018-04-04 11:01:03 UTC
2018-04-04 11:02:12.034 UTC [47] LOG:  database system is ready to accept connections
I, [2018-04-04T11:02:16.937951 #15]  INFO -- :
I, [2018-04-04T11:02:16.938359 #15]  INFO -- : > su postgres -c 'createdb discourse' || true
2018-04-04 11:02:17.014 UTC [60] postgres@postgres ERROR:  database "discourse" already exists
2018-04-04 11:02:17.014 UTC [60] postgres@postgres STATEMENT:  CREATE DATABASE discourse;
createdb: database creation failed: ERROR:  database "discourse" already exists
I, [2018-04-04T11:02:17.016859 #15]  INFO -- :
I, [2018-04-04T11:02:17.017184 #15]  INFO -- : > su postgres -c 'psql discourse -c "create user discours                                        e;"' || true
2018-04-04 11:02:17.092 UTC [71] postgres@discourse ERROR:  role "discourse" already exists
2018-04-04 11:02:17.092 UTC [71] postgres@discourse STATEMENT:  create user discourse;
ERROR:  role "discourse" already exists
I, [2018-04-04T11:02:17.094738 #15]  INFO -- :

app.yml

Summary
## this is the all-in-one, standalone Discourse Docker container template
##
## After making changes to this file, you MUST rebuild
## /var/discourse/launcher rebuild app
##
## BE *VERY* CAREFUL WHEN EDITING!
## YAML FILES ARE SUPER SUPER SENSITIVE TO MISTAKES IN WHITESPACE OR ALIGNMENT!
## visit http://www.yamllint.com/ to validate this file as needed

templates:
 - "templates/cron.template.yml"
 - "templates/postgres.template.yml"
 - "templates/redis.template.yml"
 - "templates/sshd.template.yml"
 - "templates/web.template.yml"
# - "templates/web.ratelimited.template.yml"
## Uncomment these two lines if you wish to add Lets Encrypt (https)
 - "templates/web.ssl.template.yml"
 ##- "templates/web.letsencrypt.ssl.template.yml"
 ##- "templates/web.socketed.template.yml"

## which TCP/IP ports should this container expose?
## If you want Discourse to share a port with another webserver like Apache or nginx,
## see https://meta.discourse.org/t/17247 for details
expose:
  - "25654:80"   # http
  - "443:443" # https

params:
  db_default_text_search_config: "pg_catalog.russian"

  ## Set db_shared_buffers to a max of 25% of the total memory.
  ## will be set automatically by bootstrap based on detected RAM, or you can override
  db_shared_buffers: "256MB"

  ## can improve sorting performance, but adds memory usage per-connection
  #db_work_mem: "40MB"

  ## Which Git revision should this container use? (default: tests-passed)
  #version: tests-passed

env:
  LANG: en_US.UTF-8
  # DISCOURSE_DEFAULT_LOCALE: en

  ## How many concurrent web requests are supported? Depends on memory and CPU cores.
  ## will be set automatically by bootstrap based on detected CPUs, or you can override
  UNICORN_WORKERS: 2

  ## TODO: The domain name this Discourse instance will respond to
  DISCOURSE_HOSTNAME: toxu.ru

  ## Uncomment if you want the container to be started with the same
  ## hostname (-h option) as specified above (default "$hostname-$config")
  #DOCKER_USE_HOSTNAME: true

  ## TODO: List of comma delimited emails that will be made admin and developer
  ## on initial signup example 'user1@example.com,user2@example.com'
  DISCOURSE_DEVELOPER_EMAILS: '***@yandex.ru,***@narod.ru'

  ## TODO: The SMTP mail server used to validate new accounts and send notifications
  DISCOURSE_SMTP_ADDRESS: ***.ru
  DISCOURSE_SMTP_PORT: 587
  DISCOURSE_SMTP_USER_NAME: ***.ru
  DISCOURSE_SMTP_PASSWORD: ***
  ##DISCOURSE_SMTP_ENABLE_START_TLS: true           # (optional, default true)

  ## If you added the Lets Encrypt template, uncomment below to get a free SSL certificate
  ##LETSENCRYPT_ACCOUNT_EMAIL: ***

  ## The CDN address for this Discourse instance (configured to pull)
  ## see https://meta.discourse.org/t/14857 for details
  #DISCOURSE_CDN_URL: //discourse-cdn.example.com

## The Docker container is stateless; all data is stored in /shared
volumes:
  - volume:
      host: /var/discourse/shared/standalone
      guest: /shared
  - volume:
      host: /var/discourse/shared/standalone/log/var-log
      guest: /var/log

## Plugins go here
## see https://meta.discourse.org/t/19157 for details
hooks:
  after_code:
    - exec:
        cd: $home/plugins
        cmd:
          - git clone https://github.com/discourse/docker_manager.git
          - git clone https://github.com/discourse/discourse-no-bump.git
          - git clone https://github.com/discourse/discourse-solved.git
          - git clone https://github.com/discourse/discourse-push-notifications.git
          - git clone https://github.com/communiteq/discourse-sitemap.git
          - git clone https://github.com/discourse/discourse-spoiler-alert.git
          - git clone https://github.com/discourse/discourse-cakeday.git

## Any custom commands to run after building
run:
  - exec: echo "Beginning of custom commands"
  ## If you want to set the 'From' email address for your first registration, uncomment and change:
  ## After getting the first signup email, re-comment the line. It only needs to run once.
  ## - exec: rails r "SiteSetting.notification_email='***@yandex.ru'"
  - exec: echo "End of custom commands"

So do I remove the discourse database? I do not understand.

root@bigtor:/var/discourse# ./launcher enter app
root@bigtor-app:/var/www/discourse# cd /shared/postgres_backup
root@bigtor-app:/shared/postgres_backup# sv stop unicorn
ok: down: unicorn: 0s, normally up
root@bigtor-app:/shared/postgres_backup# sudo -iu postgres dropdb discourse
root@bigtor-app:/shared/postgres_backup# sudo -iu postgres createdb discourse
root@bigtor-app:/shared/postgres_backup# sudo -iu postgres psql discourse < backup.db
bash: backup.db: No such file or directory