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pythondjangographqlgraphene-pythongraphene-django

Exposing GraphQL based APIs


I have data stored in the file system (normalized across multiple small files) and I have written python functions to read/write data from the file system. Read API returns object of type Job. Write API expects an object of type Job to be passed as an argument.

def get_jobs(starttime, endtime):
  ''' Reads and returns jobs that ran between starttime and endtime interval '''


def put_job(job):
  ''' Persists Job object to a file system '''


class Job:
    def __init__(self, name, key, starttime, endtime):
        self.name = name 
        self.key = key
        self.starttime = starttime
        self.endtime = endtime

Now I want to expose these functions via a web server. I would prefer exposing GraphQL APIs with Django.

Questions:

  • Is Django/Django REST framework a right choice for this? I am new to Django and GraphQL.
  • Django models seem to be tightly coupled with Databases. Will I have to create another Job model class, and create it using Job returned by read_jobs function? If yes, how can I create a simple web application from here?

Note:

  • Job object is a three-level nested object and has many attributes/properties. For the demonstration purpose, I kept only four attributes/properties in the question here.
  • I would prefer Django because my application at this stage might look a bit small but over time it will grow and I have lots of features that I need to add. I am specifically looking for solutions with django-graphene based application without using SQLite DB or without assuming that the data is getting fetched from some database. I want to leverage my persistence API methods for querying data from the file system.

Solution

  • Django could be a (good but heavier) solution, but here is simpler solution using Flask:

    from flask import Flask, jsonify
    
    app = Flask(__name__)
    
    class Job:
        def __init__(self, name, key, starttime, endtime):
            self.name = name 
            self.key = key
            self.starttime = starttime
            self.endtime = endtime
    
    @app.route("/get", methods=['GET'])
    def get_jobs(starttime, endtime):
        ''' Reads and returns jobs that ran between starttime and endtime interval '''
        jobs = read_data(starttime, endtime) # your read_data() method
        return jsonify({'jobs': jobs})
    
    @app.route("/put", methods=['POST'])   # or methods=['PUT']
    def put_job(request):
    
        # access your data trough the request object:
        job_name = request.args.get('name', '')
        job_key = request.args.get('key', '')
    
        # or get it in json
        job_data = request.json
    
        write_data(Job.from_json(job_data))
    

    I used Json here because I'm more confortable with it, but if GraphQL is important for you, I recommend to you the Graphene-Python library.

    There is also a project of integration of Graphene with Flask