astep-forms-utils

Module helps with generating field sets and fields for usage in the architecture aSTEP-2019 (At Aalborg Uversity). This can be used for any service written in flask, to make sure you don't create too much duplicate code. it's strongly inspired by Django.

Supported versions

Python >=3.5

Example

Create an instance of FieldSet which handles the different fields both visualized in the /fields/ endpoint as well as verified with /render/

An example with with basis in fields could be:

from astep_form_utils import FieldSet, StringField, FloatField
from flask import Flask, jsonify

app = Flask(__name__, static_url_path="")

@app.route("/fields")
def fields():
    field_set = FieldSet(
        StringField("my_name", label="Input Your Name:"),
        FloatField("my_age", label="Input Your Age:")
    )
    return jsonify(field_set.as_form_fields())

which will return json as follows:

[
  {
    "label": "Input Your Name:",
    "name": "my_name",
    "type": "input"
  },
  {
    "label": "Input Your Age:",
    "name": "my_age",
    "type": "input-number"
  }
]

You can also use enums:

from astep_form_utils import FieldSet, EnumField
from enum import Enum

class MyModel(Enum):
    PRETTY_MODEL = auto()
    UGLY_MODEL = auto()

field_set = FieldSet(
    EnumField("my_string", MyModel, label="Pick a model")
)

'

You can use a fieldset in your /render/ endpoint as well, to validate data:

from astep_form_utils import FieldSet, StringField, FloatField, is_data_empty
from flask import Flask, jsonify, request

app = Flask(__name__, static_url_path="")

@app.route("/render")
def render():
    field_set = FieldSet(
        StringField("my_name", label="Input Your Name:"),
        FloatField("my_age", label="Input Your Age:")
    )


    if is_data_empty(request):
        return jsonify({'chart_type':'text', 'content':'Supply data please!'})

    if field_set.is_valid(request):
        my_name = field_set.cleaned_data['my_name']
        my_age = field_set.cleaned_data['my_age']

        return jsonify({
            'chart_type':'text',
            'content':f'Hello my name is {my_name} and i am {my_age} years old.'
        })

To make it more DRY and reuse the FieldSet definition, you can utilize the factory function field_set_factory, to reuse the same definition like this:

from astep_form_utils import StringField, FloatField, \
    is_data_empty, field_set_factory
from flask import Flask, jsonify, request

app = Flask(__name__, static_url_path="")
# returns a method that creates a FieldSet with the two fields
FIELD_SET_FACTORY = field_set_factory(
        StringField("my_name", label="Input Your Name:"),
        FloatField("my_age", label="Input Your Age:")
)
@app.route("/render")
def render():
    # Creates a fieldset with the defined fields
    field_set =  FIELD_SET_FACTORY()

    if is_data_empty(request):
        return jsonify({'chart_type':'text', 'content':'Supply data please!'})

    if field_set.is_valid(request):
        my_name = field_set.cleaned_data['my_name']
        my_age = field_set.cleaned_data['my_age']

        return jsonify({
            'chart_type':'text',
            'content':f'Hello my name is {my_name} and i am {my_age} years old.'
        })

    raise NotImplementedError()

@app.route("/fields")
def fields():
    field_set = FIELD_SET_FACTORY() 
    return jsonify(field_set.as_form_fields())

A complete solution can be found in the implementation of the chart type test microservice.