Interfacer

This microservice application provides information about network interfaces through a simple HTTP API. It consists of two components: an HTTP server and an HTTP client, both running in separate Docker containers. The application is written in Go and deployed on Docker.

Setup

1. Prerequisites: Make sure you have Docker installed on your machine. If not, you can download and install it from Docker's official website.

---

2. Clone the Repository: Clone this repository to your local machine using the following command:

git clone github.com/AntonUrb/Milrem-Internship-Tooling.git

---

3. Navigate to the Project Root Directory: Move into the cloned repository's directory:

cd Milrem-Internship-Tooling

---

4. Build and Run the Containers: Use Docker Compose to build and run the server and client containers:

sudo docker compose -f docker-compose.yml build && sudo docker compose -f docker-compose.yml up

This command will build the Docker images for both the server and client components, create containers, and start the services.

• Troubleshooting: if you get this or any other error

Error response from daemon: network c1a87c76f774fc1ed617c48f4e0884d40b804461de60802386aa4c7df929b58e not found

run sudo docker compose down and try the first command again.

---

5. Monitoring Network Interfaces:: Once the containers are up and running, you should see the http-client start polling http-server for interfaces and printing them out in the terminal.

---

API Overview

List Network Interfaces

• Endpoint: /network

• Method: GET

• Query Parameters (Optional):

  ?interface={interface_name}: Specifies the name of a network interface. If provided, the API will return details only for the specified interface. Otherwise it returns all interfaces.

• Response Structure:

The API returns a JSON response with details about network interfaces.

200 OK: Returns details about the requested network interface(s) in JSON format.

Fields include:
    Name: The name of the network interface.
    IP Addresses: The list of IP addresses associated with the interface.
    MAC Address: The MAC (Media Access Control) address of the interface.
    MTU: The Maximum Transmission Unit of the interface.
    Speed: The speed of the interface.
    Duplex: The duplex mode of the interface (e.g., full or half).
    Admin Status: The administrative status of the interface (enabled, disabled, or unknown).
    Operational Status: The operational status of the interface (UP, DOWN, or unknown).

• Response Example:

[
  {
    "name": "eth0",
    "ip_addresses": [
        "192.168.1.10",
        "10.0.0.1"
    ],
    "mac_address": "00:11:22:33:44:55",
    "mtu": 1500,
    "speed": "1 Gbps",
    "duplex": "Full",
    "admin_status": "enabled",
    "operational_status": "UP"
  },
  {
    "name": "wlan0",
    "ip_addresses": [
        "192.168.2.20"
    ],
    "mac_address": "a1:b2:c3:d4:e5:f6",
    "mtu": 1200,
    "speed": "100 Mbps",
    "duplex": "Half",
    "admin_status": "disabled",
    "operational_status": "DOWN"
  }
]

---

Error Handling

404 Not Found is returned with an error message, if the specified interface doesn't exist.

{ "error": "interface not found" }

400 Bad Request is returned with an error message, if an invalid query parameter is provided.

{ "error": "only ?interface={interface_name} input format is allowed" }

500 Internal Server Error is returned with an error message, if an internal server error occurs.

{ "error": "internal server error" }

---

Important Notes

• The server runs on [port :8080] http://localhost:8080/network. (With this link you can also access the server in your browser)

• The HTTP-client periodically calls the server's endpoint to fetch network interface details.

• The code itself is documented and readable whenever you're curious about how something works.

Additional Information

Interval Configuration

You can modify the interval at which the HTTP client calls the server's endpoint by changing the INTERVAL environment value of http-client (e.g., 3s for 3 seconds) in the docker-compose.yml file that's located in the root directory. The default value is 5 seconds.

Interface Parameter

You can search for a specific interface which the API should display details about, by changing the INTERFACE environment value in the http-client (e.g. eth0 or wlan0) in the docker-compose.yml file that's located in the root directory. By default the value is empty, which means that all interfaces get displayed.

System with Go installed

If you have Go installed on your system, you can run both http-server and http-client directly on your system.

1. Navigate to the task's root directory.

2. Type cd client/ && make into the first terminal and cd server/ && make into the second.

This will use the Makefiles in the respective directories and run the http-server and http-client with preset environment variables. The Makefiles are also configured to automatically run test files on the API and client before launching.

---

API Test Suite

• Build and Run the HTTP Test-Server & Test-Client Containers using this command:

sudo docker compose -f docker-compose-test.yml build && sudo docker compose -f docker-compose-test.yml up

• In case of errors, run: sudo docker compose down and try the first command again.

Description:

sudo docker compose -f docker-compose-test.yml build: This part of the command builds the Docker containers for the HTTP test-server & test-client. It compiles the source code and creates the container images.

sudo docker compose -f docker-compose-test.yml up: This part of the command runs the built Docker containers for the HTTP test-server & test-client. It starts the containers and executes the defined commands within the containers, which are to use the integrated test files to test the functionality of the http-server and http-client and it's edge-cases.

---

Author

Anton Urban