Lambdee Web App

Lambdee - Scriptable Agile Board

Setup

1. bin/setup
2. Setup the postgresql server
   • psql -d template1
   • CREATE DATABASE <username>; where <username> is the name of your current system user
   • \q

Development

Commands

• bin/setup -- install/update node.js, postgresql, ruby and run bin/install
• bin/install -- install missing gems, create missing config files, execute pending migrations
• bin/debug -- run the rails backend server in debug mode
• bin/sidekiq -- run the sidekiq process
• bin/dev -- run the app with all the necessary processes in one terminal window
  • --nw or --no-watch -- run the app without automatic frontend building on file changes
  • --ns or --no-sidekiq -- run the app without running the sidekiq process
• bin/test - run all backend and frontend tests
• bin/console - run the rails console
• bin/build - build the frontend React app
• bin/openapi - build the OpenAPI documentation from Ruby specs
• bin/seed - fill the database with generated data
• bin/cypress
  • open -- open cypress for testing during development
  • run -- run cypress tests headless (without a browser window)
• bin/doc -- generate the YARD docs and open them in your browser
• bundle exec brakeman -I -- inspect backend security warnings and decide what to do with them

Architecture

Backend

The backend app is written in Ruby on Rails. It serves two purposes:

• hosting the API for the frontend app
• hosting the built frontend app

The FrontendController serves the fronted app.

All classes and modules should be named using PascalCase eg. AdminUser, UserData.

All variables and methods should be named using snake_case eg. admin_user, user_data.

All constants (not containing modules or classes) should be named using SCREAMING_SNAKE_CASE eg. ADMIN_USER, USER_DATA.

All files should be named using snake_case eg. user_data, admin_user.

REST API

All paths regarding the REST API should be defined under the /api scope.

Furthermore, controllers handling these requests should be defined under the API module.

Let's say that you want to implement a GET query for the data of a particular user.

The controller should be named API::UsersController (app/controllers/api/users_controller.rb), and the route should be /api/users/:id

We use Jbuilder views (app/views) for building JSON responses.

Documentation

We document the backend REST API with swagger/OpenAPI.

The doc file is served under /api-docs/v1/swagger.yaml, and there is a swagger web interface served under /api-docs

Plain Old Ruby Objects

All regular Ruby classes and modules should be kept inside the app/internal folder.

Database models

All ActiveRecord models (classes that represent a single record from a particular database table) should be defined under the DB namespace.

Let's say that you want to define a User model. The class should be named DB::User (app/models/db/user.rb) with the database table named users.

The app/models folder is supposed to store only ActiveRecord related classes/modules.

Configuration files

All configuration files should be located in config/ (preferably using YAML). They should be loaded in an initializer file inside config/initializers/. Values loaded from these files should be saved in Ruby constants under the Config namespace.

Let's say that you want to add a configuration file, which stores GitHub credentials. The file should be named config/github.yml. The initializer should be named config/initializers/github.rb, and the content of the config file should be saved in Config::GITHUB.

Frontend

The frontend app is written in React and lives in the frontend/ directory. It is built using esbuild and copied to the Rails Asset Pipeline, which serves it.

The React app is written in JavaScript with custom configured ESLint rules (frontend/.eslintrc.yml).

All components should be named using PascalCase eg. UserData, Board. File names follow the same convention eg. UserData.jsx.

All variables and regular (non-component) functions should be named using camelCase eg. userData, getUser.

All non-component JS files should be named using kebab-case like app-alert-store.js.

State management

UI state

This app uses zustand for creating stores for UI state. All stores are stored in frontend/src/stores.

Data fetching

SWR is used for guarding the state of data that is fetched from the backend.

All code interacting with the backend API should be located in the frontend/src/api folder.

We use Axios as our HTTP client library.

View components

Components representing a single view (page) should be stored in the frontend/src/views/ directory. Components should be written in the functional style and named using PascalCase eg. Account, UserData, ErrorButton.

Let's say that you want to write an account view. It should be stored in frontend/src/views/Account.jsx.

Any CSS styles unique to this view should be saved inside frontend/src/views/Account.css and imported in the .jsx file.

Here is an example of its code:

// frontend/src/views/Account.jsx
import './Account.css'

const Account = () => {
  return (
    <div className="account">
      <h1>Some code</h1>
    </div>
  );
}

export default Account;

Components

All other components which get used in views should be stored in the frontend/src/components/ directory. Components should be written in the functional style and named using PascalCase.

Let's say that you want to write a button component. It should be stored in frontend/src/components/Button.jsx.

Any CSS styles unique to this component should be saved inside frontend/src/components/Button.css and imported in the .jsx file.

All props used by components should be documented using the prop-types package.

Example:

// frontend/src/components/Button.jsx
import './Button.css'
import PropTypes from 'prop-types'

const Button = (props) => {
  return (
    <div className="button">
      <h1>{props.label}</h1>
    </div>
  );
}

Button.propTypes = {
  label: PropTypes.string.isRequired
}

export default Button;

Problems

Ubuntu

An error occurred while installing pg (1.3.5)

$ sudo apt install libpq-dev

LoadError: libffi.so.8: cannot open shared object file

$ curl -LO https://launchpad.net/ubuntu/+archive/primary/+files/libffi8_3.4.2-4_amd64.deb
$ sudo dpkg -i libffi8_3.4.2-4_amd64.deb

LoadError: libssl.so.1.1: cannot open shared object file

$ wget http://nz2.archive.ubuntu.com/ubuntu/pool/main/o/openssl/libssl1.1_1.1.1f-1ubuntu2.16_amd64.deb
$ sudo dpkg -i libssl1.1_1.1.1f-1ubuntu2.16_amd64.deb

Mainly MacOS

postgresql

LoadError: dlopen(/Users/mateuszdrewniak/.rvm/gems/ruby-3.1.2@lambdee-board-web-app/gems/pg-1.3.5/lib/pg_ext.bundle, 9): Library not loaded: /opt/homebrew/opt/postgresql/lib/libpq.5.dylib Referenced from: /Users/mateuszdrewniak/.rvm/gems/ruby-3.1.2@lambdee-board-web-app/gems/pg-1.3.5/lib/pg_ext.bundle Reason: image not found - /Users/mateuszdrewniak/.rvm/gems/ruby-3.1.2@lambdee-board-web-app/gems/pg-1.3.5/lib/pg_ext.bundle

Works on MacBook M1

$ sudo ln -s /opt/homebrew/opt/postgresql@14/lib/postgresql@14/libpq.5.14.dylib /opt/homebrew/opt/postgresql/libpq.5.dylib
$ sudo ln -s /opt/homebrew/opt/postgresql@14/lib/postgresql@14/libpq.5.14.dylib /opt/homebrew/opt/postgresql/lib/libpq.5.dylib

---

ActiveRecord::ConnectionNotEstablished - connection to server on socket "/tmp/.s.PGSQL.5432" failed: No such file or directory

MacBook

$ rm /usr/local/var/postgres/postmaster.pid
$ brew services restart postgresql

MacBook M1

$ rm /opt/homebrew/var/postgres/postmaster.pid
$ brew services restart postgresql

eventmachine

In file included from binder.cpp:20: ./project.h:119:10: fatal error: 'openssl/ssl.h' file not found #include <openssl/ssl.h> ^~~~~~~~~~~~~~~ 1 error generated.

1. Install openssl

$ brew install openssl

2. Check the installation path

$ brew info openssl
...
/opt/homebrew/Cellar/openssl@3/3.0.4_1 (6,442 files, 27.9MB) *
...

3. Install gem giving a path from above

$ gem install eventmachine -- --with-openssl-dir=/opt/homebrew/Cellar/openssl@3/3.0.4_1

puma

Gem::Ext::BuildError: ERROR: Failed to build gem native extension.

current directory: /Users/mateuszdrewniak/.rvm/gems/ruby-3.1.0@dupa/gems/puma-5.6.2/ext/puma_http11

/Users/mateuszdrewniak/.rvm/rubies/ruby-3.1.0/bin/ruby -I /Users/mateuszdrewniak/.rvm/rubies/ruby-3.1.0/lib/ruby/3.1.0 -r ./siteconf20220219-40641-4uxhq6.rb extconf.rb --with-cflags=-Wno-error=implicit-function-declaration

checking for BIO_read() in -lcrypto... *** extconf.rb failed ***

Could not create Makefile due to some reason, probably lack of necessary libraries and/or headers. Check the mkmf.log file for more details. You may need configuration options.

$ gem install puma -- --with-cflags="-fdeclspec"