perambluate / 110-SA-NA_WEB-DB

A Node.js app with sqlite3 db.

110-SA-NA_WEB-DB

A Node.js app with sqlite3 db.

Environment

Ubuntu 20.04

Prerequisites

• nodejs
• npm
• sqlite3

You can install nodejs, npm and sqlite3 with apt.

Installation

cd 110-SA-NA_WEB-DB
npm init
npm install express sqlite3

Add the following content in package.json for quick usage.

"scripts":{
  "start": "node app.js",
  "test": "echo 'Error'$'\n' && exit 1"
}

Usage

In the db/data.db, there is a table named kv_pairs, which saves key-value pairs as the following form, <key>|<value>. You can use the Node.js app to do the CRUD operation on this table.

[Note] The name of the key needs to be unique.

Run server

You can use either

npm start

or

node app.js

to set up the app service.

Test

curl localhost:6060

You will receive Hello Nyaaaa! if the server works.

Create

curl -X POST -H "Content-Type: application/json" \
-d '{"key":"key_name", "value":"value_content"}' \
localhost:6060/key

It will create a key named "key_name" with value "value_content".

Status

• 201 : Successfully create the key.
• 400 : Key has been already existed or some error occurs.

Read

Get a single keys

curl localhost:6060/key/<key_name>

It will return the key of name, <key_name>, in the kv_pairs table.

Get all keys

curl localhost:6060/key

It will return all key in the kv_pairs table.

Status

• 200 : Successfully get the key.
• 404 : Key not found or some error occurs.

Update

curl -X PUT -H "Content-Type: application/json" \
-d '{"value":"new_content"}' \
localhost:6060/key/<key_name>

It will update the content of value to "new_content" corresponding to the key of name, <key_name>.

Status

• 200 : Successfully update the key.
• 201 : Create the key because it's not existed.
• 400 : Some error occurs.

Delete

Delete a single key

curl -X DELETE localhost:6060/key/<key_name>

It will delete the key of name, <key_name> in the table, kv_pairs.

Delete all keys

curl -X DELETE localhost:6060/key

It will delete all the keys in the table, kv_pairs.

Status

• 200 : Successfully delete the key.
• 400 : Some error occurs.

Reference

• Build a REST API with Node.js SQLite and Express JS - Developer How-to