urlsh

urlsh is URL shortener application built on Go language.

It does not use external libraries except the gorm for postgres database and minimal redis module redigo.

Usage

Web client

Just visit urlssh.xyz. You can also integrate API for programmatic usage.

Terminal client

If you live inside the command line terminal, you can install a client:

go get github.com/adhocore/urlsh/cmd/urlshc

or, with newer go versions

go install github.com/adhocore/urlsh/cmd/urlshc

Make sure $GOPATH or $HOME/go/bin is in your $PATH or %path%, then use it like so:

# show help
urlshc -h

# shorten a url
urlshc -url 'https://your.long.url/here'

# shorten a url with keywords and expiry date
urlshc -url 'https://your.long.url/here' -keywords 'word-1,word2' -expires '2022-12-31'

# if you have self hosted or local instance of urlsh, pass in URLSH_HOST (with domain only)
URLSH_HOST=https://your.urlsh-instance.com urlshc -url 'https://your.long.url/here'

Read below for self hosting, API integration and/or contributing to urlsh.

Getting source

git clone [email protected]:adhocore/urlsh.git
cd urlsh

Configuring

It should be configured using env variables.

Please check .env.example for available variables and explanation.

DATABASE_URL is always required and is string of the following form:

DATABASE_URL=postgres://user:pass@host:port/dbname

When running urlsh with docker-compose, the preferred way, DATABASE_URL is automatically set from POSTGRES_* variables.

Please note that urlsh does not ship with .env loader so to run it in bare metal, one needs to use export KEY=VALUE or source .env manually.

If REDIS_URL is provided with redis://host:port, then it will cache popular urls, the popularity threshold is hard coded to minimal value in common.constant. The cache will sync when short url is deleted and sometimes when expired. The hit counters will however sync in realtime.

Setting up docker

To set up dockerized urlsh, run the commands below:

# first time only
cp .example.env .env

# change auth token for admin if you want in `.env` file
# APP_ADMIN_TOKEN=<something crypto secure random hash>

docker-compose up

After a few seconds, you should be able to browse to localhost:2000.

Testing

For running tests,

docker-compose exec urlsh sh -c "APP_ENV=test go test ./..."

# for coverage
docker-compose exec urlsh sh -c "APP_ENV=test go test -cover ./..."

APP_ENV=test is not required but ensures that tests are run against clone database with name prefixed by test_. Normally test db is already prepared if you use docker-compose.

API Endpoints

GET /status

Status route for health/status check.

Response payload

{
    "status": 200,
    "message": "it works"
}

POST /api/urls

Creates a new short code for given URL.

Request example

• url: string, required, http/https/ftp only
• expires_on: string, optional, utc date yyyy-mm-dd hh:mm:ss, default=9999-01-01
• keywords: array of strings, 2-25 chars each, max 10 keywords

{
    "url": "http://somedomain.com/some/very/long/url",
    "expires_on": "",
    "keywords": ["key", "word"]
}

Response example

{
    "status": 200,
    "short_code": "qaFxz",
    "short_url": "http://localhost:2000/qaFxz"
}

If env var APP_ALLOW_DUPE_URL is set to 0 or empty, then trying to shorten same URL again will return status 409 and payload will contain existing short_code. However if existing short_code is deleted, it will be shortened as usual.

GET /{shortCode}

Redirects the shortcode to original long URL.

Response payload

In case short code exists it responds with 301 redirect.

If the short code is expired or deleted, it responds like so:

{
    "status": 410,
    "message": "requested resource is not available"
}

GET /api/admin/urls

Authentication

Token required in Authorization header like so:

Authorization: Bearer <token>

Request query

The query params are optional.

page=<int>
short_code=<str>
keyword=<str>

Examples:

• /api/admin/urls?short_code=somecode
• /api/admin/urls?page=1&keyword=something

Response example

Response contains multiple matching url object inside urls array.

{
    "status": 200,
    "urls": [
        {
            "short_code": "X5JkFd",
            "origin_url": "http://somedomain.com/some/very/long/url",
            "hits": 1,
            "is_deleted": false,
            "expires_on": "9999-01-01T00:00:00Z"
        }
    ]
}

DELETE /api/admin/urls

Authentication

Token required in Authorization header like so:

Authorization: Bearer <token>

Request query

Query param short_code is requied.

Example: /api/admin/urls?short_code=somecode

Response example

If delete success:

{
    "status": 200,
    "deleted": true
}

If the code does not exist:

{
    "status": 404,
    "message": "the given short code is not found"
}

Using postman

urlsh comes with postman collection and environment to aid manual testing of endpoints.

Open the postman app, click Import at top left, select Folder and drag/choose postman folder of this repo. You may need to adjust the token in postman urlsh env if you have configured APP_ADMIN_TOKEN.

The collection comes with post/pre request hooks for requests so you can just run the endpoints one after another in postman UI.

For redirect request, you have to disable postman follow redirects from Settings > General > Automatically follow redirects.

License

Please check license file.

Other projects

My other golang projects you might find interesting and useful:

• gronx - Lightweight, fast and dependency-free Cron expression parser (due checker), task scheduler and/or daemon for Golang (tested on v1.13 and above) and standalone usage.
• fast - Check your internet speed with ease and comfort right from the terminal.
• goic - Go Open ID Connect, is OpenID connect client library for Golang, supports the Authorization Code Flow of OpenID Connect specification.
• chin - A GO lang command line tool to show a spinner as user waits for some long running jobs to finish.