File Store Application

A simple file store application consisting of a backend API and a CLI client. The backend API uses Go's net/http package, and the CLI client is built using cobra. The application allows you to add, retrieve, update, and delete text files, as well as perform word count and frequency analysis across all stored files.

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Table of Contents

• File Store Application
  • Table of Contents
  • Features
  • Requirements
  • Installation
  • Usage
    • Starting the Server
    • Building the CLI
  • Commands
  • Examples
  • Docker:
    • Step 1:
    • Step 2:
  • Kubernetes
    • Step 1. Deploy the Configuration to the Kubernetes Cluster
    • Step 2. Check for pods in the same namespace using kubectl get pods and make sure the containers in the pod are up& running
    • Step 3. Do a kubectl portforward service/file-service be able to access it outside the kind cluster
    • Step 4. Verify using curl
• License
  • This project is licensed under the MIT License.

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Features

• Add Files: Upload one or more text files to the store.
• List Files: Display all filenames currently stored.
• Retrieve File: Get the content of a specific file.
• Update File: Update the content of an existing file or add a new file.
• Delete File: Remove a file from the store.
• Word Count: Get the total word count across all stored files.
• Frequent Words: Display the most or least frequent words across all files.

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Requirements

• Go: Version 1.16 or higher. Download Go
• Cobra: For the CLI application. Install Cobra CLI
• Docker: Required for containerization and running containerized applications. Install Docker
• kubectl: Kubernetes command-line tool for interacting with Kubernetes clusters. Install kubectl
• kind: Tool for running local Kubernetes clusters using Docker container "nodes". Install kind

Note: Ensure that Docker is running before using kind and kubectl.

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Installation

1. Clone the Repository:

   git clone https://github.com/yourusername/filestore.git
   cd filestore

2. Install Dependencies: Install cobra for the CLI application:

   go get -u github.com/spf13/cobra

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Usage

Starting the Server

1. Navigate to the server directory and run the server:

   cd cmd/file-server
   go run main.go

2. The server will start on port 8080.

Building the CLI

1. Navigate to the cli directory and build the CLI application:

   cd cmd/store-client
   go build -o store main.go

2. This will create an executable named store.

Commands

1. Add Files
   Upload one or more files to the store:

   ./store add file1.txt file2.txt

2. List Files
   List all files stored on the server:

   ./store ls

3. Get File Content
   Retrieve the content of a specific file:

   ./store get file1.txt

4. Update File
   Update the content of an existing file or add a new file:

   ./store update file1.txt

5. Delete File
   Remove a file from the store:

   ./store rm file1.txt

6. Word Count
   Get the total word count across all stored files:

   ./store wc

7. Frequent Words
   Display the most or least frequent words across all files:

   ./store freq-words [--limit|-n NUMBER] [--order=asc|dsc]

Examples

1. Adding Files

   echo "Hello World" > hello.txt
   echo "Go is awesome" > go.txt
   ./store add hello.txt go.txt

2. Listing Files

   ./store ls

3. Retrieving File Content

   ./store get hello.txt

4. Updating a File

   echo "Hello Go" > hello.txt
   ./store update hello.txt
   ./store get hello.txt

5. Deleting a File

   ./store rm go.txt
   ./store ls

6. Word Count

   ./store wc

7. Frequent Words

   ./store freq-words -n 5 --order=dsc

Docker:

You can also try using the Docker build

Step 1:

docker build . -t fileserver

Step 2:

docker run -p 8081:8080 fileserver:latest

One would see the following logs and can access the server at localhost:8081/files 2024/12/03 06:31:10 Server is running on port 8080...

Kubernetes

To deploy on a Kubernetes cluster, we need to do a docker build and push to one's registry. Make sure the image is publicly available. Use kustomize tool and replace your image name accordingly in the kustomize.yaml. These steps are tried on a Kind cluster:

Step 1. Deploy the Configuration to the Kubernetes Cluster

kubectl apply -k kube/config

You would see

service/file-store-service created
deployment.apps/file-store-deployment created

➜ To get the deployments:

kubectl get deployments

You would see

NAME                    READY   UP-TO-DATE   AVAILABLE   AGE
file-store-deployment   1/1     1            1           31s

Step 2. Check for pods in the same namespace using kubectl get pods and make sure the containers in the pod are up& running

kubectl get pods

You would see

NAME                                     READY   STATUS    RESTARTS   AGE
file-store-deployment-7f9dd45957-pj2pd   1/1     Running   0          10s

Step 3. Do a kubectl portforward service/file-service be able to access it outside the kind cluster

kubectl port-forward services/file-store-service 8080:8080

You would see:

Forwarding from 127.0.0.1:8080 -> 8080
Forwarding from [::1]:8080 -> 8080
Handling connection for 8080
Handling connection for 8080

Step 4. Verify using curl

curl http://localhost:8080/files  

License

This project is licensed under the MIT License.