All 4 Developer: 2021

Monday, November 22, 2021

Gulp & React

Replace & Delete files in build folder using Gulp gulpfile.js

const gulp       = require('gulp');
const replace    = require('gulp-string-replace');
const rimraf     = require('gulp-rimraf');

function changeLang() {
    const searchFor = '<html lang="en">';
    const replaceBy = '<html lang="de">';
  
    return gulp.src('./build/*.html')
      .pipe(replace(searchFor, replaceBy))
      .pipe(gulp.dest('./build'));
}

function deleteFiles () {
  return gulp
    .src('./build/static/js/*.*.txt', { read: false })
    .pipe(rimraf());
}

exports.change_lang = changeLang;
exports.delete_files = deleteFiles;

package.json

{
  "name": "my-app",
  "version": "0.1.0",
  "private": true,
  "dependencies": {
    "@testing-library/jest-dom": "^5.11.4",
    "@testing-library/react": "^11.1.0",
    "@testing-library/user-event": "^12.1.10",
    "react": "^17.0.2",
    "react-dom": "^17.0.2",
    "react-scripts": "4.0.3",
    "web-vitals": "^1.0.1"
  },
  "scripts": {
    "start": "react-scripts start",
    "build": "react-scripts build && npm run gulp-change-language && npm run gulp-delete_files",
    "test": "react-scripts test",
    "eject": "react-scripts eject",
    "gulp-change-language": "gulp change_lang",
    "gulp-delete_files": "gulp delete_files"
  },
  "eslintConfig": {
    "extends": [
      "react-app",
      "react-app/jest"
    ]
  },
  "browserslist": {
    "production": [
      ">0.2%",
      "not dead",
      "not op_mini all"
    ],
    "development": [
      "last 1 chrome version",
      "last 1 firefox version",
      "last 1 safari version"
    ]
  },
  "devDependencies": {
    "gulp": "^4.0.2",
    "gulp-rimraf": "^1.0.0",
    "gulp-string-replace": "^1.1.2"
  }
}

Test gulp

npm run build

Friday, November 19, 2021

CSP and Dynamically Generated JavaScript tag

CSP HTTP header and Meta Tag must be synchronized. There must be two hashes one for hard coded JavaScript other for generated JavaScript tag.

index.html

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta http-equiv="X-UA-Compatible" content="ie=edge" />
    <title>Content Security Policy Demo</title>
    <meta http-equiv="Content-Security-Policy" content="default-src 'self'; font-src 'self' ; img-src 'self' https://images.unsplash.com ; script-src 'self' 'sha256-B/8L7bCoRRLbK80hqzXcLc/NSWDtHVADDkdElr18Q2U=' 'sha256-BQBWQMByG186hXi3h+x/zUK8eOCr3iy91FDzS9uKCNs='; style-src 'self' https://cdn.jsdelivr.net; frame-src 'self'">
    <link rel="stylesheet" href="style.css" />
    <link
      rel="stylesheet"
      href="https://cdn.jsdelivr.net/npm/bootstrap@4.5.3/dist/css/bootstrap.min.css"
      integrity="sha384-TX8t27EcRE3e/ihU7zmQxVncDAy5uIKz4rEkgIXeMed4M0jlfIDPvg6uqKI2xXr2"
      crossorigin="anonymous"
      />
    <script src="node_modules/jquery/dist/jquery.min.js"></script>
  </head>
  <body>
    <script type = "text/javascript" >
      $(document).ready(function() {
         $('div.grid').after('<div>new element</div>');
      });
      let newScript = document.createElement("script");
      let inlineScript = document.createTextNode("alert('Hello World!');");
      newScript.appendChild(inlineScript);
      $(document.body).append(newScript);
    </script>
    <div class="box">
      <div class="grid">
        <img
          src="https://images.unsplash.com/photo-1535089780340-34cc939f9996?ixlib=rb-1.2.1&auto=format&fit=crop&w=500&q=80"
          alt=""
          />
        <img
          src="https://images.unsplash.com/photo-1587081917197-95be3a2d2103?ixlib=rb-1.2.1&auto=format&fit=crop&w=500&q=80"
          alt=""
          />
        <img
          src="https://images.unsplash.com/photo-1502248103506-76afc15f5c45?ixlib=rb-1.2.1&ixid=eyJhcHBfaWQiOjEyMDd9&auto=format&fit=crop&w=500&q=80"
          alt=""
          />
      </div>
    </div>
  </body>
</html>

server.js

const express = require('express');
const bodyParser = require('body-parser');
const path = require('path');
const app = express();
 
app.use(function (req, res, next) {
  res.setHeader(
    'Content-Security-Policy',
    "default-src 'self'; font-src 'self' ; img-src 'self' https://images.unsplash.com ; script-src 'self' 'sha256-B/8L7bCoRRLbK80hqzXcLc/NSWDtHVADDkdElr18Q2U=' 'sha256-BQBWQMByG186hXi3h+x/zUK8eOCr3iy91FDzS9uKCNs='; style-src 'self' https://cdn.jsdelivr.net; frame-src 'self'"
  );
  next();
});
 
app.use(bodyParser.json());
app.use(express.static(path.join(__dirname)));
 
app.get('/', (req, res) => {
  res.sendFile(path.join(__dirname + '/index.html'));
});
 
const server = app.listen(process.env.PORT || 5500, () => {
  const { port } = server.address();
  console.log(`Server running on PORT ${port}`);
});

package.json

{
  "name": "csp-javascript",
  "version": "1.0.0",
  "main": "index.js",
  "license": "MIT",
  "scripts": {
    "start": "npx nodemon server.js"
  },
  "dependencies": {
    "body-parser": "^1.19.0",
    "express": "^4.17.1",
    "jquery": "^3.6.0"
  },
  "devDependencies": {
    "nodemon": "^2.0.6"
  }
}

Monday, November 15, 2021

GitLab Pipeline and React

GitLab for React

Make sure you are using same node image in the pipeline and Dockerfiles

optimised .gitlab-ci.yml using artifacts

stages:
  - build
  - test
  - push

image:
  name: node:16-alpine
  entrypoint: [""]

build_r:
  stage: build
  artifacts:
    paths:
      - node_modules/
      - package.json
      - package-lock.json
    expire_in: 1 day
  before_script:
    - apk -U upgrade
  script:
    - node -v
    - ls -lA
    - npm install
    - ls -lA
  only:
    - main

test_r:
  stage: test
  before_script:
    - apk -U upgrade
  script:
    - ls -lA
    - CI=true npm test
  only:
    - main

push_r:
  stage: push
  image:
    name: gcr.io/kaniko-project/executor:debug
    entrypoint: [""]
  script:
    - echo "{\"auths\":{\"$CI_REGISTRY\":{\"username\":\"$CI_REGISTRY_USER\",\"password\":\"$CI_REGISTRY_PASSWORD\"}}}" > /kaniko/.docker/config.json
    - /kaniko/executor --cache=false --context $CI_PROJECT_DIR --dockerfile $CI_PROJECT_DIR/Dockerfile-prod --destination $CI_REGISTRY_IMAGE:$CI_COMMIT_SHORT_SHA 
  only:
    - main

.gitlab-ci.yml using cache

stages:
  - build
  - test
  - push

cache:
  key: "$CI_COMMIT_REF_SLUG"
  paths:
    - node_modules/

image:
  name: node:16-alpine

build_r:
  stage: build
  before_script:
    - export ENV_VAR="value"
  script:
    - node -v
    - echo "$ENV_VAR"
    - echo "$CI_COMMIT_REF_SLUG"
    - npm install
  only:
    - main

test_r:
  stage: test
  script:
    - echo "$CI_COMMIT_REF_SLUG"
    - CI=true npm test
  only:
    - main

push_r:
  stage: push
  image:
    name: gcr.io/kaniko-project/executor:debug
    entrypoint: [""]
  script:
    - echo "{\"auths\":{\"$CI_REGISTRY\":{\"username\":\"$CI_REGISTRY_USER\",\"password\":\"$CI_REGISTRY_PASSWORD\"}}}" > /kaniko/.docker/config.json
    - /kaniko/executor --cache=false --context $CI_PROJECT_DIR --dockerfile $CI_PROJECT_DIR/Dockerfile-prod --destination $CI_REGISTRY_IMAGE:$CI_COMMIT_SHORT_SHA 
  only:
    - main

Dockerfile

FROM node:16-alpine

RUN apk -U upgrade

WORKDIR /app

COPY package.json ./

RUN npm install

COPY ./ ./

CMD ["npm", "start"]

Dockerfile-prod

FROM node:16-alpine as build

WORKDIR /usr/app

COPY package.json .

RUN npm install

COPY  . .

RUN REACT_APP_BASE_URL=example.com yarn build

FROM nginx:1.19.0

WORKDIR /usr/share/nginx/html

RUN rm -rf ./*

COPY --from=build /usr/app/build /usr/share/nginx/html

ENTRYPOINT ["nginx", "-g", "daemon off;"]

This will work for any react app that has tests.

On target machine:

docker login registry.gitlab.com
docker run -it --name react registry.gitlab.com/USER-NAME/IMAGE-NAME:TAG

Friday, September 10, 2021

Apache on Ubuntu

Dockerfile for installing Apache on Ubuntu:

FROM ubuntu:20.04

ENV TZ=Europe/Berlin

RUN ln -snf /usr/share/zoneinfo/$TZ /etc/localtime && echo $TZ > /etc/timezone

RUN apt-get update && apt-get -y install apache2

EXPOSE 80

CMD ["/usr/sbin/apachectl", "-D", "FOREGROUND"]

Build and run

docker build -t ubu-apache .
docker run --name=ubu-apache -d -p 80:80 -v $(pwd)/html/:/var/www/html/ ubu-apache

Enter in container. Tail logs and list files in html folder

docker exec -it ubu-apache /bin/bash

root@8c138884f9a3:/# tail -f /var/log/apache2/error.log

root@8c138884f9a3:/# tail -f /var/log/apache2/access.log

root@8c138884f9a3:/# ls -l /var/www/html

Sunday, July 18, 2021

React CheckBox

Working with React Bootstrap checkbox

 import React, { PureComponent } from "react";
import Form from "react-bootstrap/Form";

interface CheckBoxState {
  checkedColors: any[];
}

interface CheckBoxProps {
  foo: string;
}

class CheckBox extends PureComponent<CheckBoxProps, CheckBoxState> {
  constructor(props: CheckBoxProps) {
    super(props);
    this.state = {
      checkedColors: [
        { isChecked: false, name: "chk1", label: "blue" },
        { isChecked: false, name: "chk2", label: "red" },
      ],
    };
  }

  render() {
    return (
      <div>
        {this.state.checkedColors.map((item: any) => (
          <Form.Check
            type="checkbox"
            id={item.name}
            inline
            key={item.name}
            checked={item.isChecked}
            onChange={(event: any) => this.handleChange(event)}
            label={item.label}
          />
        ))}
        <button onClick={() => console.log(this.state.checkedColors)}>
          Show checked colors
        </button>

        <hr />
        {this.props.foo}
      </div>
    );
  }

  handleChange(event: any): void {
    const checkedColors = [...this.state.checkedColors];

    checkedColors.map((item: any) => {
      if (item.name === event.target.id) item.isChecked = event.target.checked;
    });

    this.setState({
      checkedColors,
    });
  }
}

export default CheckBox;

Note that this.state.checkedColors can be cloned using spread operator 'cause the array is shallow.

Friday, May 7, 2021

Postgres & Adminer on Docker

Postgres & Adminer on Docker stack.

version: '3'

services:

  postgres:
    image: postgres:13.2-alpine
    restart: always
    environment:
      POSTGRES_PASSWORD: secret
      POSTGRES_USER: pguser
      POSTGRES_DB: pgdb
    ports:
      - "5432:5432"
    volumes:
      - pg-data:/var/lib/postgresql/data
    networks:
      - pg-network
 

  adminer:
    image: adminer:4.8.0-standalone
    restart: always
    ports:
      - "8080:8080"
    networks:
      - pg-network

networks:
  pg-network:
    driver: bridge

volumes:
  pg-data:
    driver: local

This will set up the two services on the same network and assign a volume for the database.

Thursday, April 15, 2021

TypeScript Question Mark and Exclamation Mark

Here is how to use in combination to determine if property is null or undefined.

interface Product {
    id: number,
    name?: any 
}

let product: Product = {id: 5, name: "some str"};

if(product!.name) console.log("ok")

product = {id: 5}
if(product!.name) console.log("not printed")

product = {id: 5, name: null}
if(product!.name) console.log("not printed")

Second if will not be excecated 'cause property name is not defined. Third if will not be execute 'cause property name is null.

Thursday, February 4, 2021

Oracle Spool

Here is how to create a log file for your script:

SET echo ON
SET feedback ON
SET SERVEROUTPUT ON
SET linesize 500
COL spoolname new_value filename
SELECT TO_CHAR(systimestamp, 'YYYY_MM_DD_HH24_MI_') || 
	(SELECT SYS_CONTEXT ('userenv', 'current_schema') FROM  dual) || 
	'_log_name.log' AS spoolname FROM dual;
SPOOL &filename

-- start main SQL script
INSERT INTO my_table (total) VALUES (25);
-- end main SQL script

SPOOL OFF
EXIT;

This will create a log file with name like this 2019_11_11_23_00_schema_name_log_name.log.

Thursday, January 21, 2021

Oracle Package

Oracle package with procedure, function and global variable

CREATE OR REPLACE PACKAGE my_package AS
    g_fav_num NUMBER := 5;
    PROCEDURE my_proc (val INTEGER);
    FUNCTION  double_func (in_val IN NUMBER) RETURN NUMBER; 
END my_package;
/

CREATE OR REPLACE PACKAGE BODY my_package ASPROCEDURE my_proc (val INTEGER) IS
  BEGIN
      g_fav_num := g_fav_num + val;
      INSERT INTO my_table ( total ) VALUES ( double_func(g_fav_num) );
  END;

  FUNCTION double_func (in_val IN NUMBER) RETURN NUMBER IS 
  BEGIN 
    RETURN in_val*2;
  END;

END my_package;
/

exec my_package.my_proc(1000);