Deploying a FastAPI microservice means making it accessible to users on a server, so they can use it to perform some functionality. Deploying the microservice typically involves installing the necessary dependencies on the server, copying the microservice code to the server, and starting the microservice using a web server.
There are different ways to deploy a FastAPI microservice, such as running it directly on a server, deploying it as a Docker container, or deploying it to a cloud platform. Regardless of the method used, it's important to follow best practices to ensure the microservice is secure, reliable, and performs well.
Deploying a FastAPI microservice can be a complex process, but with proper planning and execution, it can be done effectively.
Deploy FastAPI Microservice
Deploying a FastAPI microservice can be done in several ways. Here are some common methods:
Running the microservice directly on a server:
Here are the detailed steps to deploy a FastAPI microservice by running it directly on a server, along with some example code:
STEP 1: Set up the server:
You will need to set up a server with an operating system that meets the requirements for running a FastAPI application. The server should have Python 3.6 or higher installed, along with any required libraries. For this example, we will use Ubuntu 18.04 and Python 3.9.
Here are the steps to set up a server using Ubuntu 18.04:
# Update package lists
sudo apt-get update
# Install Python 3.9
sudo apt-get install python3.9# Install pip for Python 3.9
sudo apt-get install python3.9-venv python3.9-dev python3-pipSTEP 2: Copy the code to the server:
Next, you will need to copy the code for your FastAPI application to the server. This can be done using tools such as Git or FTP.
For this example, we will assume that the code is stored in a Git repository, and we will use Git to copy the code to the server. Here are the steps to copy the code:
# Install Git
sudo apt-get install git
# Clone the repository
git clone https://github.com/username/repository.git
# Change directory to the cloned repositorycd repositorySTEP 3: Install dependencies:
Once the code is on the server, you will need to install any dependencies required by the FastAPI application. You can use a package manager such as pip to install the dependencies.
For this example, we will assume that the FastAPI application has the following dependencies: fastapi, uvicorn, and pydantic. Here are the steps to install the dependencies:
# Create a virtual environment for the application
python3.9 -m venv venv
# Activate the virtual environmentsource venv/bin/activate
# Install the dependencies
pip install fastapi uvicorn pydanticSTEP 4: Start the FastAPI application:
Finally, you can start the FastAPI application using a production-ready web server such as Uvicorn.
For this example, we will assume that the FastAPI application is defined in a file named main.py, and it has a single route that returns a JSON response. Here is the example code for the FastAPI application:
from fastapi import FastAPI
app = FastAPI()
@app.get("/")async def read_root():
return {"Hello": "World"}Here are the steps to start the FastAPI application using Uvicorn:
# Start the application using Uvicorn
uvicorn main:app --host 0.0.0.0 --port 8000The --host option specifies the IP address that the application will listen on, and --port specifies the port number. In this example, the application will listen on all IP addresses (0.0.0.0) on port 8000.
Once the application is started, you can access it by visiting http://<server-ip>:8000 in a web browser. In this example, <server-ip> is the IP address of the server.
Deploying the microservice as a Docker container:
STEP 1: Set up Docker:
To deploy a FastAPI microservice as a Docker container, you will need to have Docker installed on your machine. You can follow the instructions on the official Docker website to install Docker on your machine.
STEP 2: Write a Dockerfile:
Next, you will need to write a Dockerfile that specifies how to build the Docker image for your FastAPI application. The Dockerfile should include instructions to install any dependencies required by the application, and to copy the application code into the Docker image.
Here is an example Dockerfile for a simple FastAPI application:
# Use the official Python image as the base image
FROM python:3.9
# Set the working directory to /app
WORKDIR /app
# Copy the current directory contents into the container at /app
COPY . /app
# Install the required packages
RUN pip install --no-cache-dir -r requirements.txt
# Expose port 80 for the container
EXPOSE 80
# Start the FastAPI application using Uvicorn
CMD ["uvicorn", "main:app", "--host", "0.0.0.0", "--port", "80"]
This Dockerfile assumes that your FastAPI application is defined in a file named main.py, and that the application has a file named requirements.txt that lists its dependencies. It also assumes that the application listens on port 80.
STEP 3: Build the Docker image:
Once you have written the Dockerfile, you can use the docker build command to build the Docker image for your FastAPI application. The command should be run in the same directory as the Dockerfile.
docker build -t my-fastapi-app .This command builds a Docker image named my-fastapi-app using the Dockerfile in the current directory.
STEP 4: Run the Docker container:
Finally, you can use the docker run command to run the Docker container for your FastAPI application.
docker run -p 80:80 my-fastapi-appThis command runs the Docker container and maps port 80 in the container to port 80 on the host machine.
Once the container is running, you can access the FastAPI application by visiting http://localhost:80 in a web browser.
Note that you can customize the docker run command with additional options to control the behavior of the container. For example, you can use the -d option to run the container in detached mode, or the --name option to give the container a specific name.
Deploying the microservice to a cloud platform:
Deploying a microservice to a cloud platform can vary depending on the cloud provider and the technology stack used for the microservice. In general, the process involves the following steps:
STEP 1: Choose a cloud platform: There are several cloud platforms to choose from, such as Amazon Web Services (AWS), Microsoft Azure, Google Cloud Platform (GCP), and more. Each platform has its own strengths and weaknesses, so choose the one that best suits your needs.
STEP 2: Containerize your microservice: Containerization is a popular way to package and deploy microservices. It involves creating a Docker image of your microservice and running it as a container. You can use a Dockerfile to specify the image configuration and dependencies. Here's an example of a Dockerfile for a simple Node.js microservice:
# Use an official Node.js runtime as a parent image
FROM node:14
# Set the working directory to /app
WORKDIR /app
# Copy the package.json and package-lock.json files to the working directory
COPY package*.json ./
# Install dependencies
RUN npm install
# Copy the rest of the application code to the working directory
COPY . .
# Expose the port the microservice will listen on
EXPOSE 3000
# Start the microservice
CMD [ "npm", "start" ]STEP 3: Push the Docker image to a container registry: Once you have created the Docker image, you can push it to a container registry, such as Docker Hub, Amazon ECR, or GCP Container Registry. This makes the image available for deployment to your cloud platform.
STEP 4: Set up your cloud environment: Depending on your cloud platform, you may need to set up a virtual machine or a container cluster to run your microservice. You'll also need to configure networking, security, and other infrastructure components. Here's an example of how to create a Kubernetes cluster on GCP using the gcloud command-line tool:
# Create a Kubernetes cluster
gcloud container clusters create my-cluster --num-nodes=2# Configure kubectl to use the new cluster
gcloud container clusters get-credentials my-clusterSTEP 5: Deploy the microservice: Finally, you can deploy the Docker image to your cloud environment. This typically involves creating a deployment object that specifies the container image and any other configuration options. Here's an example of how to deploy the Docker image to a Kubernetes cluster on GCP:
# Create a deployment object
kubectl create deployment my-service --image=my-image
# Expose the deployment as a Kubernetes service
kubectl expose deployment my-service --type=LoadBalancer --port=80 --target-port=3000This creates a load balancer that routes traffic to your microservice running on port 3000.
These are just a few examples of how to deploy a microservice to a cloud platform. The exact process may vary depending on the technology stack and cloud platform you're using.
Best Practice to follow
Regardless of the deployment method, here are some best practices to follow:
Use a production-ready web server, such as Gunicorn or Uvicorn, to run the FastAPI microservice.
Use environment variables to store sensitive information, such as passwords or API keys, and avoid hard-coding them in the code.
Use a logging framework, such as Python's built-in logging or Loguru, to log important events and errors in the microservice.
Use a process manager, such as Systemd or Supervisor, to manage the microservice's process and ensure that it starts automatically after a reboot or a crash.
Monitor the microservice's health and performance using a monitoring tool, such as Prometheus or New Relic, and use the collected data to identify and fix any issues.