docs: Add documentation

00_HelloWorld/app.py

@@ -17,6 +17,12 @@ def running_in_docker():
 
 @app.route("/")
 def hello_world():
+    """Root endpoint that provides MongoDB server version.
+
+    Returns:
+        str: A message indicating connection to MongoDB with its version.
+    """
+
     # This will set the mongo host as localhost by default if variable is not set
     # NOTE! localhost won't work with containers, this is setting "mongodb-server" as default,
     # otherwise this can be set by "docker run" + "-e MONGODB_HOST=<mongodb_server_name> ... etc"
@@ -30,7 +36,6 @@ def hello_world():
     client = MongoClient(f"mongodb://{mongodb_host}:27017/")
     db = client.test_db
     return "Connected to MongoDB version: " + str(db.command("serverStatus")["version"])
-    # return "Hello World"
 
 
 if __name__ == "__main__":

00_HelloWorld/build.py

@@ -3,7 +3,19 @@
 
 
 def create_network(client, network_name):
-    """Ensure the Docker network exists or create it if it doesn't."""
+    """Ensure a Docker network exists or create it if it doesn't.
+
+    This function checks if the specified Docker network exists. If it doesn't,
+    it attempts to create a new network with the given name using the bridge driver.
+
+    Args:
+        client: A Docker client object created with docker.from_env() or similar.
+        network_name: The name of the Docker network to check or create.
+
+    Raises:
+        APIError: An error occurred when attempting to communicate with Docker API
+                  during network creation.
+    """
     try:
         network = client.networks.get(network_name)
         print(f"Network '{network_name}' already exists.")
@@ -16,7 +28,21 @@ def create_network(client, network_name):
 
 
 def build_image(client, tag, path="."):
-    """Build a Docker image from a Dockerfile."""
+    """Build a Docker image from a Dockerfile.
+
+    This function builds a Docker image based on the Dockerfile located at the specified path.
+    It tags the resulting image with the provided tag. It prints the build logs to the console
+    and indicates success or failure.
+
+    Args:
+        client: A Docker client object.
+        tag: The tag to assign to the built image.
+        path: The path to the directory containing the Dockerfile. Defaults to the current directory.
+
+    Raises:
+        BuildError: An error occurred during the build process.
+        APIError: An error occurred when attempting to communicate with Docker API.
+    """
     try:
         _, build_log = client.images.build(path=path, tag=tag, rm=True)
         for line in build_log:
@@ -30,7 +56,18 @@ def build_image(client, tag, path="."):
 
 
 def check_and_pull_image(client, image_name):
-    """Check for an image locally and pull it if not found."""
+    """Check for an image locally and pull it from Docker Hub if not found.
+
+    This function checks if the specified Docker image is available locally. If it's not found,
+    it attempts to pull the image from Docker Hub.
+
+    Args:
+        client: A Docker client object.
+        image_name: The name of the image to check and potentially pull.
+
+    Raises:
+        ImageNotFound: The specified image is not found locally and an attempt is made to pull it.
+    """
     try:
         client.images.get(image_name)
         print(f"Image '{image_name}' is already available.")

00_HelloWorld/clean.py

@@ -3,7 +3,19 @@
 
 
 def stop_and_remove_container(client, container_name):
-    """Stop and remove a Docker container by its name."""
+    """Stops and removes a specified Docker container.
+
+    This function attempts to stop and forcibly remove a Docker container by its name. It handles
+    cases where the container might not exist (either already stopped or removed) and logs appropriate
+    messages to the console.
+
+    Args:
+        client: A Docker client object created with docker.from_env() or similar.
+        container_name: The name of the Docker container to stop and remove.
+
+    Raises:
+        docker.errors.APIError: An error occurred when attempting to stop or remove the container due to issues with Docker API.
+    """
     try:
         container = client.containers.get(container_name)
         container.stop()  # Stops the container
@@ -18,7 +30,18 @@ def stop_and_remove_container(client, container_name):
 
 
 def remove_network(client, network_name):
-    """Remove a Docker network by its name."""
+    """Removes a specified Docker network.
+
+    This function tries to remove a Docker network by its name. It deals with cases where the network
+    may not be found (potentially already removed) and logs appropriate messages to the console.
+
+    Args:
+        client: A Docker client object.
+        network_name: The name of the Docker network to remove.
+
+    Raises:
+        docker.errors.APIError: An error occurred when attempting to remove the network due to issues with Docker API.
+    """
     try:
         network = client.networks.get(network_name)
         network.remove()

00_HelloWorld/run.py

@@ -15,7 +15,34 @@ def run_container(
     remove=False,
     working_dir=None,
 ):
-    """Attempts to start a Docker container with the specified configuration."""
+    """
+    Starts a Docker container based on the specified parameters.
+
+    This function attempts to run a Docker container using the provided image and configuration. It
+    supports setting the container's name, ports, network, environment variables, and working directory.
+    The function handles exceptions related to image availability, container errors, and API issues, logging
+    appropriate messages. It can optionally remove the container upon exit.
+
+    Args:
+        client: A Docker client object created with docker.from_env() or similar.
+        name: A string specifying the name of the container.
+        image: A string specifying the Docker image to use for the container.
+        ports: A dictionary mapping container ports to host ports, e.g., {"container_port/tcp": host_port}.
+        command: Optional; the command to run in the container.
+        network: Optional; the network to connect the container to.
+        environment: Optional; a dictionary of environment variables to set in the container.
+        remove: Optional; a boolean indicating whether to automatically remove the container when it exits.
+        working_dir: Optional; the working directory to set for the command to run in.
+
+    Returns:
+        A Docker container object if the container starts successfully. None if an error occurs.
+
+    Raises:
+        ImageNotFound: Raised when the specified Docker image is not available.
+        ContainerError: Raised when there's an error in container execution.
+        APIError: Raised when the Docker API encounters an error.
+        Exception: Catches and logs unexpected errors during container run.
+    """
     try:
         container = client.containers.run(
             image,

01_CRUD/app.py

@@ -1,8 +1,7 @@
-import os
-
 from flask import Flask, jsonify, request
 from pymongo import MongoClient
 
+import os
 
 app = Flask(__name__)
 
@@ -21,12 +20,24 @@
 
 @app.route("/")
 def index():
+    """Root endpoint that provides MongoDB server version.
+
+    Returns:
+        str: A message indicating connection to MongoDB with its version.
+    """
     return "Connected to MongoDB version: " + str(db.command("serverStatus")["version"])
 
 
 # CREATE
 @app.route("/products", methods=["POST"])
 def add_product():
+    """Creates a new product in the database.
+
+    The product data is expected in JSON format in the request body.
+
+    Returns:
+        tuple: JSON response with the creation message and the new product ID, along with the HTTP status code 201.
+    """
     product_data = request.get_json()
     result = db.products.insert_one(product_data)
     return (
@@ -39,6 +50,13 @@ def add_product():
 
 @app.route("/users", methods=["POST"])
 def add_user():
+    """Creates a new user in the database.
+
+    The user data is expected in JSON format in the request body.
+
+    Returns:
+        tuple: JSON response with the creation message and the new user ID, along with the HTTP status code 201.
+    """
     user_data = request.get_json()
     result = db.users.insert_one(user_data)
     return (
@@ -52,6 +70,14 @@ def add_user():
 # READ
 @app.route("/products/<product_id>", methods=["GET"])
 def get_product(product_id):
+    """Fetches a single product from the database by its product_id.
+
+    Args:
+        product_id (str): The ID of the product to retrieve.
+
+    Returns:
+        tuple: JSON response with the product data if found, along with the HTTP status code. 404 if not found.
+    """
     product = db.products.find_one({"product_id": product_id})
     if product:
         product["_id"] = str(product["_id"])
@@ -62,6 +88,14 @@ def get_product(product_id):
 
 @app.route("/users/<username>", methods=["GET"])
 def get_user(username):
+    """Fetches a single user from the database by username.
+
+    Args:
+        username (str): The username of the user to retrieve.
+
+    Returns:
+        tuple: JSON response with the user data if found, along with the HTTP status code. 404 if not found.
+    """
     user = db.users.find_one({"username": username})
     if user:
         user["_id"] = str(
@@ -75,6 +109,14 @@ def get_user(username):
 # UPDATE
 @app.route("/products/<product_id>", methods=["PUT"])
 def update_product(product_id):
+    """Updates a product in the database identified by its product_id.
+
+    Args:
+        product_id (str): The ID of the product to update.
+
+    Returns:
+        tuple: JSON response with an update success message, along with the HTTP status code. 404 if not found.
+    """
     update_data = request.get_json()
     result = db.products.update_one({"product_id": product_id}, {"$set": update_data})
 
@@ -86,6 +128,14 @@ def update_product(product_id):
 
 @app.route("/users/<username>", methods=["PUT"])
 def update_user(username):
+    """Updates a user in the database identified by username.
+
+    Args:
+        username (str): The username of the user to update.
+
+    Returns:
+        tuple: JSON response with an update success message, along with the HTTP status code. 404 if not found.
+    """
     update_data = request.get_json()
     result = db.users.update_one({"username": username}, {"$set": update_data})
 
@@ -98,6 +148,14 @@ def update_user(username):
 # DELETE
 @app.route("/products/<product_id>", methods=["DELETE"])
 def delete_product(product_id):
+    """Deletes a product from the database by its product_id.
+
+    Args:
+        product_id (str): The ID of the product to delete.
+
+    Returns:
+        tuple: JSON response with a deletion success message, along with the HTTP status code. 404 if not found.
+    """
     result = db.products.delete_one({"product_id": product_id})
 
     if result.deleted_count:
@@ -108,6 +166,14 @@ def delete_product(product_id):
 
 @app.route("/users/<username>", methods=["DELETE"])
 def delete_user(username):
+    """Deletes a user from the database by username.
+
+    Args:
+        username (str): The username of the user to delete.
+
+    Returns:
+        tuple: JSON response with a deletion success message, along with the HTTP status code. 404 if not found.
+    """
     result = db.users.delete_one({"username": username})
 
     if result.deleted_count:

01_CRUD/build.py

@@ -3,7 +3,19 @@
 
 
 def create_network(client, network_name):
-    """Ensure the Docker network exists or create it if it doesn't."""
+    """Ensure a Docker network exists or create it if it doesn't.
+
+    This function checks if the specified Docker network exists. If it doesn't,
+    it attempts to create a new network with the given name using the bridge driver.
+
+    Args:
+        client: A Docker client object created with docker.from_env() or similar.
+        network_name: The name of the Docker network to check or create.
+
+    Raises:
+        APIError: An error occurred when attempting to communicate with Docker API
+                  during network creation.
+    """
     try:
         network = client.networks.get(network_name)
         print(f"Network '{network_name}' already exists.")
@@ -16,7 +28,21 @@ def create_network(client, network_name):
 
 
 def build_image(client, tag, path="."):
-    """Build a Docker image from a Dockerfile."""
+    """Build a Docker image from a Dockerfile.
+
+    This function builds a Docker image based on the Dockerfile located at the specified path.
+    It tags the resulting image with the provided tag. It prints the build logs to the console
+    and indicates success or failure.
+
+    Args:
+        client: A Docker client object.
+        tag: The tag to assign to the built image.
+        path: The path to the directory containing the Dockerfile. Defaults to the current directory.
+
+    Raises:
+        BuildError: An error occurred during the build process.
+        APIError: An error occurred when attempting to communicate with Docker API.
+    """
     try:
         _, build_log = client.images.build(path=path, tag=tag, rm=True)
         for line in build_log:
@@ -30,7 +56,18 @@ def build_image(client, tag, path="."):
 
 
 def check_and_pull_image(client, image_name):
-    """Check for an image locally and pull it if not found."""
+    """Check for an image locally and pull it from Docker Hub if not found.
+
+    This function checks if the specified Docker image is available locally. If it's not found,
+    it attempts to pull the image from Docker Hub.
+
+    Args:
+        client: A Docker client object.
+        image_name: The name of the image to check and potentially pull.
+
+    Raises:
+        ImageNotFound: The specified image is not found locally and an attempt is made to pull it.
+    """
     try:
         client.images.get(image_name)
         print(f"Image '{image_name}' is already available.")