Added support for CD and environment variables

.env.example

@@ -0,0 +1 @@
+MONGO_AUTH_CREDENTIALS=""

.github/workflows/deploy_to_prod.yml

@@ -0,0 +1,37 @@
+# This workflow will update the code for the production environment
+
+on:
+  push:
+    branches: ["release"]
+
+name: Deploy to production
+
+jobs:
+  build_and_deploy:
+    name: Deploy
+    environment:
+      name: Production
+
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+
+      - name: Set up Python
+        uses: actions/setup-python@v2
+
+      - name: Set up SAM
+        uses: aws-actions/setup-sam@v1
+
+      - name: Configure AWS Credentials
+        uses: aws-actions/configure-aws-credentials@v1
+        with:
+          aws-access-key-id: ${{ secrets.AWS_ACCESS_KEY_ID }}
+          aws-secret-access-key: ${{ secrets.AWS_SECRET_ACCESS_KEY }}
+          aws-region: us-east-1
+
+      - name: Build
+        run: sam build --use-container -t templates/prod.yaml
+
+      - name: Deploy
+        run: sam deploy --stack-name QuizBackendProd --s3-bucket quiz-prod-backend --no-confirm-changeset --no-fail-on-empty-changeset --region us-east-1 --capabilities CAPABILITY_IAM --parameter-overrides MongoAuthCredentials=${{ secrets.MONGO_AUTH_CREDENTIALS }}

.github/workflows/deploy_to_staging.yml

@@ -0,0 +1,38 @@
+# This workflow will update the code for the staging environment
+
+on:
+  pull_request:
+  push:
+    branches: ["main"]
+
+name: Deploy to staging
+
+jobs:
+  build_and_deploy:
+    name: Deploy
+    environment:
+      name: Staging
+
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+
+      - name: Set up Python
+        uses: actions/setup-python@v2
+
+      - name: Set up SAM
+        uses: aws-actions/setup-sam@v1
+
+      - name: Configure AWS Credentials
+        uses: aws-actions/configure-aws-credentials@v1
+        with:
+          aws-access-key-id: ${{ secrets.AWS_ACCESS_KEY_ID }}
+          aws-secret-access-key: ${{ secrets.AWS_SECRET_ACCESS_KEY }}
+          aws-region: us-east-1
+
+      - name: Build
+        run: sam build --use-container -t templates/staging.yaml
+
+      - name: Deploy
+        run: sam deploy --stack-name QuizBackendStaging --s3-bucket quiz-staging-backend --no-confirm-changeset --no-fail-on-empty-changeset --region us-east-1 --capabilities CAPABILITY_IAM --parameter-overrides MongoAuthCredentials=${{ secrets.MONGO_AUTH_CREDENTIALS }}

README.md

@@ -34,6 +34,8 @@ pip install pre-commit
 pre-commit install
 ```
 
+- Copy `.env.example` to `.env` and set all the environment variables as mentioned in `docs/ENV.md`.
+
 ## Running locally
 
 Simply run:
@@ -58,53 +60,6 @@ Use `http://127.0.0.1:8000` as the base URL of the endpoints and navigate to `ht
 
 ## Deployment
 
-- Install [AWS SAM CLI](https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/serverless-sam-cli-install.html)
-
-- Install Docker and start Docker.
-
-### Staging
-
-- Create the deployment stack (only required for the first time):
-
-```bash
-sam deploy --stack-name QuizBackendStaging --s3-bucket quiz-staging-backend --capabilities CAPABILITY_IAM -t templates/staging.yaml
-```
-
-If the deployment was successful, you should see a message as shown in the image below:
-![deployment successful](images/deployment-succeeded.png)
-
-The app will be deployed on the URL corresponding to `Value` in the image above!
-
-- Once the stack has been deployed, subsequent changes to the code can be uploaded to the lambda function by running:
-
-```bash
-sam sync --stack-name QuizBackendStaging -t templates/staging.yaml
-```
-
-- If you want your files to automatically be synced to your deployment, simply add `--watch` at the end of the previous command.
-
-```
-sam sync --stack-name QuizBackendStaging -t templates/staging.yaml --watch
-```
-
-### Production
-
-The steps are similar to that in Staging.
-
-- Create the deployment stack (only required for the first time):
-
-```
-sam deploy --stack-name QuizBackendProd --s3-bucket quiz-prod-backend --capabilities CAPABILITY_IAM -t templates/prod.yaml
-```
+We are deploying our FastAPI instance on AWS Lambda which is triggered via an API Gateway. In order to automate the process, we are using [AWS SAM](https://www.youtube.com/watch?v=tA9IIGR6XFo&ab_channel=JavaHomeCloud), which creates the stack required for the deployment and updates it as needed with just a couple of commands and without having to do anything manually on the AWS GUI. Refer to [this](https://www.eliasbrange.dev/posts/deploy-fastapi-on-aws-part-1-lambda-api-gateway/) blog post for more details.
 
-- Once the stack has been deployed, subsequent changes to the code can be uploaded to the lambda function by running:
-
-```
-sam sync --stack-name QuizBackendProd -t templates/prod.yaml
-```
-
-- If you want your files to automatically be synced to your deployment, simply add `--watch` at the end of the previous command.
-
-```
-sam sync --stack-name QuizBackendProd -t templates/prod.yaml --watch
-```
+The actual deployment happens through Github Actions. Look at [`.github/workflows/deploy_to_staging.yml`](.github/workflows/deploy_to_staging.yml) for understanding the deployment to `Staging` and [`.github/workflows/deploy_to_prod.yml`](.github/workflows/deploy_to_prod.yml) for `Production`. Make sure to set all the environment variables mentioned in [`docs/ENV.md`](docs/ENV.md) in the `Production` and `Staging` environments in your Github repository.

app/database.py

@@ -1,5 +1,12 @@
+import os
 from pymongo import MongoClient
 
-client = MongoClient(
-    "mongodb+srv://quiz:p$#p4h7y_Z44R-n@cluster0.uocfg.mongodb.net/quiz?retryWrites=true&w=majority"
-)
+# this is required for loading environment variables when
+# running the app locally as the environment variable should
+# be set when the app is running on staging/production by Github Actions
+if "MONGO_AUTH_CREDENTIALS" not in os.environ:
+    from dotenv import load_dotenv
+
+    load_dotenv("../.env")
+
+client = MongoClient(os.getenv("MONGO_AUTH_CREDENTIALS"))

app/requirements.txt

@@ -4,3 +4,4 @@ pymongo==4.0.2
 uvicorn==0.17.6
 dnspython==2.2.1
 mangum==0.14.1
+python-dotenv==0.20.0

app/schemas.py

@@ -36,4 +36,4 @@ class QuizLanguage(Enum):
 
 class QuizType(Enum):
     assessment = "assessment"
-    jee = "JEE"
+    homework = "homework"

docs/ENV.md

@@ -0,0 +1,7 @@
+## Environment Variables
+
+### `MONGO_AUTH_CREDENTIALS`
+
+Credentials to connect to your MongoDB instance.
+
+**NOTE**: While setting this value in the `Production` and `Staging` environments on Github, make sure to include the value within double quotes and escape any characters using `\` as necessary. If you don't set this correctly, your deployment will fail.

templates/prod.yaml

@@ -2,6 +2,11 @@ AWSTemplateFormatVersion: "2010-09-09"
 Transform: AWS::Serverless-2016-10-31
 Description: Quiz Backend - Prod - FastAPI on Lambda
 
+Parameters:
+  MongoAuthCredentials:
+    Type: String
+    Description: Credentials to connect to the MongoDB instance
+
 Resources:
   Function:
     Type: AWS::Serverless::Function
@@ -10,6 +15,9 @@ Resources:
       CodeUri: ../app
       Handler: main.handler
       Runtime: python3.9
+      Environment:
+        Variables:
+          MONGO_AUTH_CREDENTIALS: !Ref MongoAuthCredentials
       Events:
         Api:
           Type: HttpApi

templates/staging.yaml

@@ -2,6 +2,11 @@ AWSTemplateFormatVersion: "2010-09-09"
 Transform: AWS::Serverless-2016-10-31
 Description: Quiz Backend - Staging - FastAPI on Lambda
 
+Parameters:
+  MongoAuthCredentials:
+    Type: String
+    Description: Credentials to connect to the MongoDB instance
+
 Resources:
   Function:
     Type: AWS::Serverless::Function
@@ -10,6 +15,9 @@ Resources:
       CodeUri: ../app
       Handler: main.handler
       Runtime: python3.9
+      Environment:
+        Variables:
+          MONGO_AUTH_CREDENTIALS: !Ref MongoAuthCredentials
       Events:
         Api:
           Type: HttpApi