pupsik/FastApi-example

FastApi Example

FastApi app example. The purpose of this API is to serve as the intermediary layer between the web client and the third party House Canary API.

Quick Start

Secrets

This API is making authenticated requests to the House Canary API.

For the purposes of this tutorial, you need to create a local secrets folder at the root of the repository named <api_key>.txt that contains yous <api_secret>.

In order to do so, run the following commands at the root of the repository:

mkdir secrets
echo "my_api_secret" >> secrets/my_api_key.txt

Validate that you now have the secrets folder and the secret above is correctly placed inside the folder.

Running the Service

This tutorial expects that you have docker installed locally and have understanding of how to use it. If you don't have docker installed, please follow the instructions here:

In your terminal, run the following commands:

docker compose build fast-api
docker compose up fast-api

Making Requests

curl http://localhost:5000/api/has_septic_system?address=123+Main+St+Natick+MA+01748

Expected response:

{"has_septic_system":false}

Documentation

API docs can be accessed at:

http://localhost:5000/docs

Further Use Cases

Request:

curl http://localhost:5000/api/has_septic_system?address=123+Main+St

Expected response:

status_code = 400
response = Unable to validate user supplied property address

Request:

curl http://localhost:5000/api/has_septic_system

Expected response:

status_code=422
response = {"detail":[{"loc":["query","address"],"msg":"field required","type":"value_error.missing"}]}

Request:

curl http://localhost:5000/api/has_septic_system?address=444+Unhandled+St

Expected response:

status_code=503
response = {"detail":"Failed to obtain successful response from third party providers."}

Few Notes on Mock Server Set Up

The service is using PostMan Mock Server with the end-points detailed below. The response models are abbreviated for simplicity.

Success Scenarios:

GET https://40a2af34-f05f-4ca4-aa6b-c6eb444ff269.mock.pstmn.io/property/geocode?address=123+Main+St+Natick+MA+01748

Response Code: 200

{
    "property/geocode": {
        "api_code": 0,
        "api_code_description": "ok",
        "result": true
    },
    "address_info": {
        "address_full": "123 Main St Natick MA 01748",
        "slug": "123-Main-Street-Natick-MA-01748"
    },
    "status": {
        "match": true,
        "errors": []
    }
}


GET https://40a2af34-f05f-4ca4-aa6b-c6eb444ff269.mock.pstmn.io/property/geocode?address=123+Main+St

Response Code: 200

{
    "property/geocode": {
        "api_code": 0,
        "api_code_description": "ok",
        "result": true
    },
    "address_info": {
        "address_full": "123 Main St",
        "slug": ""
    },
    "status": {
        "match": false,
        "errors": []
    }
}

GET https://40a2af34-f05f-4ca4-aa6b-c6eb444ff269.mock.pstmn.io/property/details?address=123-Main-Street-Natick-MA-01748

Response Code 200

{
    "property/details": {
        "api_code_description": "ok",
        "api_code": 200,
        "result": {
            "property": {
                "air_conditioning": "yes",
                "sewer": "municipal",
                "style": "colonial",
                "pool": true
            }
        }
    }
}

Failure Scenarios:

GET https://40a2af34-f05f-4ca4-aa6b-c6eb444ff269.mock.pstmn.io/property/geocode?address=568+Right+St

Response Code: 400

"Missing required fields or incorrect request structure"

GET https://40a2af34-f05f-4ca4-aa6b-c6eb444ff269.mock.pstmn.io/property/geocode?address=444+Unhandled+St

Response Code 500

"Internal Server Error"

Further Considerations:

1. Add logging - all web client requests should be logged and all House Canary requests should be logged. Both logs should be joinabled on the same request ID so that we can trace which web client requests resulted in which House Canary API requests.

2. Rate limiting - set rate limiting on our API

3. Add docker container for tests - build a separate container, separate requirements and add to docker compose

4. Add "lock-requirements" script and docker container to build requirements.

5. Add retries on thid party API calls for certain types of errors (must be mindful of the third-party API rate limits)

6. Improve secret handling - secrets should be encrypted.

7. Set up CI/CD pipeline

8. Expand error handling for more scnearios