Surface code (refactoring)

intro.md

Context

You come across this patch as a pull request. It's only green lines (additions) with the following commit message.

commit 2f159dcef7412a88175debfef54d317a162c1999 (HEAD -> origin/bobby-dev/add-surface-api)
Author: Bobby Developer <[email protected]>
Date:   Fri Apr 14 11:46:01 2023 +0200
 
    Surfaces: Start fetching surfaces from external service

    I found this API that can use to fetch roof surfaces for a given address. It's a bit convoluted, but it works™.

cloud/surfaces/surfaces.py | 93 +-
1 file changed, 93 insertion(+), 0 deletion(-)

Your task

Read through and think out loud: What does this code do?

surfaces.py

import logging
import requests
import sentry_sdk
from contextlib import suppress
from json import JSONDecodeError

from django.conf import settings
from rest_framework import status

from cloud.surfaces.api import make_request, poll_job_result

logger = logging.getLogger(__name__)

def get_surfaces(address: Address) -> list[dict]:
    response = make_request(
        settings.SURFACES_SERVICE_URL,
        cadastral_unit_id=address.cadastral_unit_id,
        cadastral_address_id=address.cadastral_address_id,
    )

    if 'application/json' in response.headers.get('Content-Type'):
        data = response.json()
        response_status = data.get('ResponseStatus', {})
        if response_status:
            logger.info('Found response status (test 1)')
        message = {}
        if 'Message' in data and data['Message']:
            with suppress(JSONDecodeError):
                message = json.loads(data['Message'])

        response_status = message.get('ResponseStatus', {})
        if response_status:
            logger.info('Found response status (test 2)')

        if 'Cannot find any buildings for' in message:
            logger.info(f'No buildings found on address {address} (test 1)')
            return []

        error_code = None
        if 'ErrorCode' in response_status:
            logger.info('Found ErrorCode in response_status')
            error_code = response_status.get('ErrorCode', '')
        elif 'Message' in data and 'ErrorCode' in data['Message']:
            error_code = message.get('ErrorCode', '')

        if error_code:
            if 'no-buildings' in error_code:
                logger.info(f'No buildings found on address {address} (test 2)')
                return []

            logger.error(
                f'Unable to get surface data. Error code: {error_code}',
                exc_info=True,
            )
            return []

    if response.status_code == status.HTTP_404_NOT_FOUND:
        return []

    try:
        response.raise_for_status()
    except requests.exceptions.RequestException:
        logger.info('Unable to refresh surfaces')
        sentry_sdk.capture_exception()
        return []

    data = response.json()

    if not data['Success']:
        logger.error(
            'Unable to refresh surfaces',
            exc_info=True,
            extra={'data': {'url': settings.SURFACES_SERVICE_URL, 'response': data}},
        )
        return []

    if not data['Completed']:
        response = poll_job_result(data['JobId'])
    else:
        url = f'{settings.SURFACE_JOB_DOWNLOAD_URL}?JobId={data['JobId']}'
        response = session.get(
            url,
            headers={
                'Content-Type': 'application/json',
                'Accept': 'application/json',
                'X-WAAPI-TOKEN': settings.SURFACE_API_KEY,
            },
        )

    response.raise_for_status()

    return response.json()['roofs']