Lecture: DevOps - application

This repository contains the application that should be used as deployable workload for the exercise implementation.

Getting started

For more information regarding the app, please take a look into its README.

The Makefile in this directory can be seen as the main entry point for this repository. It's meant to locally run the application and mess around with the source code in order to better understand how it works and to be able to tear it apart if necessary. Additionally, it documents various invocations that may help you adapting this application as workload for the exercise.

Please note, that the Makefile is only meant to showcase steps that are usually needed to be taken in order to automate the deployment lifecycle of such an application and code base. It is NOT recommended to invoke make targets from the CI/CD, but rather to utilize platform-specific interfaces (e.g. Jenkinsfile, .travis.yml, etc.), which may then invoke commands shown in the make target or in the scripts section of one of the package.json files.

Prerequisites

The following software must be installed and available in your ${PATH}:

• node (NodeJS)
• npm (npm)
• mongod (MongoDB)

NOTE: required versions

Option 1

Choose for yourself how you want to install these dependencies. Perhaps you can use the package manager available on your operating system, or maybe you prefer using container images.

Option 2

Install all executables via Makefile into this project structure.

a) from the root directory:

make deps

b) from the ./hack folder:

$(cd ./hack && make install)

Don't forget to add the new folder (./.local/bin ) to your ${PATH} variable in your shell environment:

export PATH=$(pwd)/.local/bin:${PATH}

Commands

The following commands are available from the root directory:

make install

• installs all dependencies via npm for server and client

make build

• builds the client code
• copies it over into the server

make test

NOTE: requires a MongoDB service to already run (see MONGODB_URL in target on where it's assumed to be running)

• runs client & server tests in CI mode (exits regardless of the test outcome; closed tty)

make dev-test-client

NOTE: only demonstrates a use case during local development and are not meant to run in any other context (e.g. automation)

• runs client tests in a local development mode

make dev-start-db

NOTE: only demonstrates a use case during local development and are not meant to run in any other context (e.g. automation)

• starts a local MongoDB service

make dev-start-app

NOTE (1): only demonstrates a use case during local development and are not meant to run in any other context (e.g. automation) NOTE (2): it might be desired to first start a database service (e.g. make dev-start-db)

• builds client (see make build)
• starts server in development mode and with development configuration

make run

NOTE (1): showcases plain executable invocation with a shared parent process. Press Ctrl+C to send termination signal. NOTE (2): in reality those two services would always be invoked independently and never share a parent process!

• starts a MongoDB service as a child process with an explicit inline-configuration
• starts the application service with variables being set in a way so that they are only visible to that invocation (as an alternative to the configuration file app/server/dev.env that is used to set environment variables)
• blocks terminal and keeps it as output device until termination signal is being send.

make clean

• removes all node_modules dependencies that have been installed locally via npm

make deps

• installs the software prerequisites as prebuild binaries locally in .local/bin

make nuke

• removes all npm dependencies (see make clean)
• throws away .local folder and thus all software prerequisites that were installed within it