This is a Django backend for sátni.org that uses Mongodb to serve a GraphQL-endpoint to the sátni.org-frontend application.

The development of this backend is most easily done in a Linux environment. On Mac, the needed fsts must be compiled and installed from source.

Prerequisites

• Install and setup mongodb
• Install apertium-nightly
  • Install the packages giella-fin, giella-nob, giella-sma, giella-sme, giella-smj, giella-smn, giella-sms, python3-hfst
• Checkout the langtech svn repo parallel to this one (svn checkout https://gtsvn.uit.no/langtech/trunk langtech)
• Set the environment variable GTHOME to point to the working copy of langtech
• Fetch poetry

Initial setup

• cp .env.example to .env
• set the app secret (follow the link in .env)
• set the mongodb username and password

poetry install # install dependencies

Use poetry env list and poetry config --list to find out where the active virtual environment is. Open the file pyvenv.cfg, change the line include-system-site-packages = false to include-system-site-packages = true. This step is needed because hfst sometimes is uninstallable using poetry (pip, setuptools), and we need to use the system packages instead.

poetry run python manage.py migrate # migrate the database
poetry run python manage.py runscript from_dump # import content from langtech

Development

Set DEBUG=True in .env, then run the following command

poetry run python manage.py runserver

Find out which queries are available by going to the built-in GraphQL IDE at http://localhost:8000/graphql/

Null the database, migrate and import content

./init_backend.sh

The startup of this repo was the Django and GraphQL intro

GraphQL schema

To dump the schema, run:

poetry run python manage.py graphql_schema --out schema.graphql

Queries

The examples below query the production server. If you'd like to do queries on the development server, use the url http://localhost:8000/graphql/ instead of https://satni.uit.no/newsatni/

Get all the possible queries

curl https://satni.uit.no/newsatni/ \
-H 'Content-Type: application/json' \
-H 'Accept: application/json' \
--compressed \
--data-binary '{"query":"{ __schema{  queryType { fields{ name } } } }"}'

Gives this answer:

{
  "data": {
    "__schema": {
      "queryType": {
        "fields": [
          {
            "name": "conceptList"
          },
          {
            "name": "dictEntryList"
          },
          {
            "name": "stemList"
          },
          {
            "name": "hasStem"
          }
        ]
      }
    }
  }
}

stemList

Search the database for lookup words.

Download lemmas.json and run the command:

curl https://satni.uit.no/newsatni/ \
-H 'Content-Type: application/json' \
-H 'Accept: application/json' \
--compressed \
--data-binary '@lemmas.json'

This command looks for first hundred search words starting with "arg" from our database. The variable inputValue is used to define what we look for. The list srcLangs tells which languages the search word should be in, the list targetLangs tells which languages the search should have a translation for. The list wantedDicts tells which dictionaries we would like answers from.

Edit lemmas.json to experiment with the query.

conceptList and dictEntryList

Get dictionary and terminology articles.

Download articles.json and run the command:

curl https://satni.uit.no/newsatni/ \
-H 'Content-Type: application/json' \
-H 'Accept: application/json' \
--compressed \
--data-binary '@articles.json'

This command looks for articles that has bil as a lookup word. The variable lemma is used to define this. lemma must be an exact hit, usually this is fetched from the stemlist. The list srcLangs tells which languages the lookup word should be in, the list targetLangs tells which languages the lookup word should have a translation for. The list wantedDicts tells which dictionaries we would like answers from.

Edit articles.json to experiment with the query.

hasStem

Used to decide whether stem is in the stemList. In satni-frontend this is used to decide if a reverse lookup can be done from a translation. The list targetLangs tells which languages the lookup word should have a translation for. The list wantedDicts tells which dictionaries we would like answers from.

Download hasStem.json and run the command:

curl https://satni.uit.no/newsatni/ \
-H 'Content-Type: application/json' \
-H 'Accept: application/json' \
--compressed \
--data-binary '@hasStem.json'

generated

Used to generate wordforms from a paradigm template.

The generator returns a list where each element contains a paradigm template and a list of wordforms generated from that paradigm template.

To see an example of the results of this query, download generated.json and run the command:

curl https://satni.uit.no/newsatni/ \
-H 'Content-Type: application/json' \
-H 'Accept: application/json' \
--compressed \
--data-binary '@generated.json'

lemmatised

Used to analyse wordforms sent to the lemmatiser.

The lemmatiser returns a list containing info about the language of the lemmatiser, a list of lemmatised wordforms and a list of analyses of the queried wordform.

The list of lemmatised wordforms can be used to query the dictionaries, the analyses can be used to explain the different analyses of the given wordform.

To see an example of the results of this query, download lemmatised.json and run the command:

curl https://satni.uit.no/newsatni/ \
-H 'Content-Type: application/json' \
-H 'Accept: application/json' \
--compressed \
--data-binary '@lemmatised.json'

Find all capabilities

To get a complete overview what this backend offers, download all.json and do the command:

curl https://satni.uit.no/newsatni/ \
-H 'Content-Type: application/json' \
-H 'Accept: application/json' \
--compressed \
--data-binary '@all.json'

Deployment using systemd

Login as the user that should run the service. Clone this repo in the root of the home directory. Check out the langtech svn repo as described above in the root of the home directory, as well. Do all the other steps as described in the Prerequisites section.

Move into the satni-backend directory, then run these commands:

• loginctl enable-linger. This allows users who are not logged in to run long-running services
• mkdir -p ~/.config/systemd/user/
• cp satni.service.example ~/.config/systemd/user/satni.service
• poetry shell
• which gunicorn

Edit ~/.config/systemd/user/satni.service, replace virtualenv-path/gunicorn with the result you got from which gunicorn

Managing the service

• systemctl --user start satni
• systemctl --user stop satni
• systemctl --user restart satni

Checking the status

• systemctl --user status satni
• journalctl --user-unit satni