Python Flask REST API Tutorial

Python Flask REST API Tutorial

I am sharing my Python code to create simple REST API. I have used Python's lightweight framework Flask is used to create simple REST API. Flask Restful is an extension of Flask. This code may helpful for some beginner Python developer. 

from flask import Flask

from flask_restful import Resource, Api

app = Flask(__name__)

api = Api(app)

class HelloWorld(Resource):

    def get(self):

        return {'hello': 'world'}

api.add_resource(HelloWorld, '/')

if __name__ == '__main__':

    app.run(debug=True)

Print CSV Content in Python Tutorial

As CSV is most common file to import and export data on web applications. So we may need to use this feature in almost our most of the apps. So I am sharing my small Python code to print CSV data into an array. May this code is helpful for someone.

We need CSV module of Python for this code to run. We used CSV module `reader` function to read CSV content in Python.

import csv

results = []

with open('test.csv', newline='') as csvfile:

    reader = csv.reader(csvfile, delimiter=' ', quotechar='|')

    for row in reader:

        results.append(row)

print("CSV data: ", results)

More details on CSV module of Python, please follow below URL:

https://docs.python.org/3/library/csv.html

Python Basics 

 Python is an easy to learn, powerful programming language. It has efficient high-level data structures and a simple but effective approach to object-oriented programming.

Python is an interpreted language, which can save you considerable time during program development because no compilation and linking is necessary.

Python is extensible: with C/C++/Java code, and easily embeddable in applications.

Some Python modules are also useful as scripts.

Python source files are treated as encoded in UTF-8.

Start the interpreter and wait for the primary prompt, >>>.

The interpreter acts as a simple calculator. The operators +, -, * and / work just like in most other languages.

Python can also manipulate strings.  They can be enclosed in single quotes (‘) or double quotes (“). 

Simple print command in Python.

print("Hello world")

Math Commands acts like a calculator.

>>> 2 + 2

4

>>> 17 / 3  # classic division returns a float

5.666666666666667

>>> 5 * 3 + 2  # result * divisor + remainder

17

>>> width = 20

>>> height = 5 * 9

>>> width * height

900

If Statement in Python: Below example is asking to input integer value. isdigit() function is checking if provided value in of type int.

Try Except statements are used for catching any exception. It protects any exception if we don't enter any

input.

try:

    x = int(input("Please enter number: "))

    if x.isdigit():

        if x <= 0:

            x = 0

            print('Printing 0 value')

        elif x < 10:

            print('Printing ' + str(x))

        else:

            print('Value is very big')

except:

    print("Please enter valid input")

For Loop Below example printing hexa code of colors by their name in Python.

Install colour package of Python

pip install colour

Ref: https://pypi.org/project/colour/

Converts and manipulates common color representation (RGB, HSL, web, …)

from colour import Color

colors = ['red', 'green', 'white', 'blue']

for c in colors:

    n = Color(c)

    print(c, n.hex)

Fibonacci Series in Python as follows:

# Fibonacci series:

# the sum of two elements defines the next

a, b = 0, 1

while a < 10:

    print(a)

    a, b = b, a+b

For loop in Python:

a = 0 b = [] for a in range(0, 10): b.append(4 + ((a - 1) * 3)) s = ',' . join(str(c) for c in b) print(s) // print array elements in string

Function in Python:

def parrot(a, b, c):

print(a,b,c)

d = {"a": "this", "b": " is my ", "c": "test"}

parrot(**d)

AWS X-ray Send Traces Lumen

AWS X-ray Test Script in PHP Framework Lumen

I have tested sending traces to AWS X-Ray through API Gateway through Lumen.

I have used below PHP package:

https://packagist.org/packages/pkerrigan/xray

<?php

namespace App\Http\Controllers\API;

use App\Http\Controllers\Controller;

use Illuminate\Http\Request;

use App\Support\Response;

use Pkerrigan\Xray\Trace;

use Pkerrigan\Xray\Submission\DaemonSegmentSubmitter;

use Pkerrigan\Xray\Segment;

class TestController extends Controller

{

    /**

     * construct

     */

    public function __construct(Response $response) {

        $this->response = $response;

    }

    /**

     * test xray

     */

    public function xray() {    

      try {  

        if(env('ENABLE_XRAY')) {

              //echo "----Tracing Start 14 ----";

              Trace::getInstance()

                ->setTraceHeader($_SERVER['HTTP_X_AMZN_TRACE_ID'] ?? null)

                ->setName('api-1')

                ->setUrl("[API-1-URL]")

                ->setMethod('GET')

                ->begin();

              Trace::getInstance()

                ->setTraceHeader($_SERVER['HTTP_X_AMZN_TRACE_ID'] ?? null)

                ->setName('api-2')

                ->setUrl("[API-2-URL]")

                ->setMethod('GET')

                ->begin();

                

              Trace::getInstance()

                ->setTraceHeader($_SERVER['HTTP_X_AMZN_TRACE_ID'] ?? null)

                ->setName('api-3')

                ->setUrl("[API-3-URL]")

                ->setMethod('GET')

                ->begin();    

                  

              Trace::getInstance()

              ->getCurrentSegment()

              ->end()

              ->setResponseCode(http_response_code())

              ->submit(new DaemonSegmentSubmitter());

              return $this->response->success(array('xray-res' => 'success'));

          } else {

            return $this->response->success(array('xray-res' => 'no-set'));

          }

        } catch(Exception $e) {

          return $this->response->success(array('xray-res' => $e->getMessage()));

        }

    }

}

GIT Pull Using Nodejs

GIT Pull Using Nodejs

I am sharing my code to take GIT pull through NodeJS. May be this small code can help someone.

// create config module

var config = {};

to_dir_client = "path to folder...";

client_git_repo = "Bitbucket URL... ";

// export config object as a node module

export default config;

/*-----------------------------------------------------------

--- install git repo js file

-----------------------------------------------------------*/

// include modules

import config, { to_dir_client, client_git_repo } from './config';

import gitP from 'simple-git/promise';

// install repo

const git_client = gitP(to_dir_client);

git_client.checkIsRepo()

   .then(isRepo => !isRepo && initialiseClientRepo(git_client))

   .then(() => git_client.pull('origin', 'master'));

// function to add origin

function initialiseClientRepo (git) {

   return git.init()

      .then(() => git.addRemote('origin', client_git_repo))

}

SonarQube Scanner Local Windows

SonarQube Scanner Windows

I am sharing my tutorial to describes how to run a Sonar Scanner on Windows machine.

Add the project to SonarQube, In SonarQube, go to

Enter Project Key

Enter Project Key which can be used later to identify the project.

New project created. 

Download SonarQube Scanner

https://docs.sonarqube.org/latest/analysis/scan/sonarscanner/

Windows Installer

Install SonarQube on Windows

Installation Guide

Go through the installation and running scanner manual online https://docs.sonarqube.org/latest/analysis/scan/sonarscanner/

  My Local Instance

    My test local instance looks like

There is only one file to review t.php

My sonar.json looks like

My sonar-project.properties file looks like:

Running Sonar Scanner CLI

After scanning is done, we can see report in Sonarqube console like below:

Speech to Voice in Website using Javascript

Speech to Voice in Website using Javascript

W3C Community introduced the Web Speech API specification. Its a wonderful feature to introduce voice enabled commands on your website which works in Chrome Browser.

Convert Speech to Text

Below code just convert voice speech to text that you can use to make any search on your website or to navigate to another link on your website. Also you can make simple Bot on your website using this feature.

window.SpeechRecognition = window.webkitSpeechRecognition || window.SpeechRecognition;

console.log(window.SpeechRecognition);

if ('SpeechRecognition' in window) {

    const recognition = new window.SpeechRecognition();

    recognition.onresult = (event) => {

        let speechToText = event.results[0][0].transcript;

        console.log("speech text", speechToText);

    }

    recognition.start();

    console.log('Ready to receive a command.');

} else {

    alert("speaking not working");

    // speech recognition API not supported

}

Below code is used to output speech on Chrome browser.
speechSynthesis.getVoices(); method is used to get voices from various countries accents.

var m = 'Hi How are you?';

if ('speechSynthesis' in window) {

    const msg = new SpeechSynthesisUtterance(m);

    const voices = window.speechSynthesis.getVoices();

    // msg.voice = voices[9];

    //msg.voice = voices[4];

    console.log("speaking: " + m);

}