sdavids-docker-healthcheck

Table of Contents

• 1. Size Comparison
  • 1.1. Go
    • 1.1.1. http
    • 1.1.2. https
  • 1.2. Java
    • 1.2.1. http
  • 1.3. JavaScript
    • 1.3.1. Node.js
  • 1.4. Rust
    • 1.4.1. http
    • 1.4.2. https
  • 1.5. shell
    • 1.5.1. nc
  • 1.6. curl
    • 1.6.1. alpine
    • 1.6.2. debian
  • 1.7. wget
    • 1.7.1. alpine
    • 1.7.2. debian
• 2. Development
  • 2.1. Format Source Code
  • 2.2. Lint Source Code
• 3. Development Environment Setup
  • 3.1. Installation
    • 3.1.1. Docker
    • 3.1.2. easyrsa
    • 3.1.3. Go
    • 3.1.4. golangci-lint
    • 3.1.5. hadolint
    • 3.1.6. JDK
    • 3.1.7. Node Version Manager
    • 3.1.8. Rust
    • 3.1.9. shellcheck
    • 3.1.10. shfmt
    • 3.1.11. yamllint

Available Docker health checks:

Go http

a Go-based Docker health check for an HTTP URL

Go https

a Go-based Docker health check for an HTTP(S) URL

Java http

a Java-based Docker health check for an HTTP URL

JavaScript Node.js

a Node.js-based Docker health check for an HTTP(S) URL

Rust http

a Rust-based Docker health check for an HTTP URL

Rust https

a Rust-based Docker health check for an HTTP(S) URL

shell nc

a nc-based Docker health check for a daemon port

1. Size Comparison

Program	Size	Notes
shell nc	4.0K	only check the daemon’s port
JavaScript Node.js	4.0K	the node binary would add 41.8M
Rust http	208.0K
Rust https	548.0K
Java http	4.3M
Go http	5.6M
Go https	5.6M
wget alpine	8.7M
wget debian	9.7M
curl alpine	9.8M
curl debian	19.0M

1.1. Go

1.1.1. http

$ cd go/http
$ scripts/docker_build.sh -p linux/amd64 -t go-http
$ docker run --platform=linux/amd64 --rm de.sdavids/sdavids-docker-healthcheck:go-http sh -c 'du -kh /usr/local/bin/healthcheck'
5.6M    /usr/local/bin/healthcheck

Usage

Go http

1.1.2. https

$ cd go/https
$ scripts/docker_build.sh -p linux/amd64 -t go-https
$ docker run --platform=linux/amd64 --rm de.sdavids/sdavids-docker-healthcheck:go-https sh -c 'du -kh /usr/local/bin/healthcheck'
5.6M    /usr/local/bin/healthcheck

Usage

Go https

1.2. Java

1.2.1. http

$ cd java/http
$ scripts/docker_build.sh -p linux/amd64 -t java-http
$ docker run --platform=linux/amd64 --rm de.sdavids/sdavids-docker-healthcheck:java-http sh -c 'du -kh /usr/local/bin/healthcheck'
4.3M    /usr/local/bin/healthcheck

Usage

Java http

1.3. JavaScript

1.3.1. Node.js

ℹ️	This health check is only useful in a Node.js Docker image, i.e., an image where the node binary already exists—​the node binary would add 41.8M.

$ cd js/nodejs
$ scripts/docker_build.sh -p linux/amd64 -t js-nodejs
$ docker run --platform=linux/amd64 --rm de.sdavids/sdavids-docker-healthcheck:js-nodejs sh -c 'du -kh /node/healthcheck.mjs'
4.0K    /node/healthcheck.mjs
$ docker run --platform=linux/amd64 --rm de.sdavids/sdavids-docker-healthcheck:js-nodejs sh -c 'du -kh /usr/bin/node'
41.8M   /usr/bin/node

Usage

js - nodejs

1.4. Rust

1.4.1. http

$ cd rust/http
$ scripts/docker_build.sh -p linux/amd64 -t rust-http
$ docker run --platform=linux/amd64 --rm de.sdavids/sdavids-docker-healthcheck:rust-http sh -c 'du -kh /usr/local/bin/healthcheck'
208.0K  /usr/local/bin/healthcheck

Usage

Rust http

1.4.2. https

ℹ️	You need to create a certificate authority and its root certificate: $ cd rust/https $ scripts/create_ca.sh $ scripts/copy_ca_root_cert.sh Or copy an existing root certificate: $ cd rust/https $ scripts/copy_ca_root_cert.sh

$ cd rust/https
$ scripts/docker_build.sh -p linux/amd64 -t rust-https
$ docker run --platform=linux/amd64 --rm de.sdavids/sdavids-docker-healthcheck:rust-https sh -c 'du -kh /usr/local/bin/healthcheck'
548.0K  /usr/local/bin/healthcheck

Usage

Rust https

1.5. shell

1.5.1. nc

ℹ️	This health check will only check if the daemon’s port is reachable, i.e., it will not check the HTTP body or status code of the response.

$ cd shell/nc
$ scripts/docker_build.sh -p linux/amd64 -t shell-nc
$ docker run --platform=linux/amd64 --rm de.sdavids/sdavids-docker-healthcheck:shell-nc sh -c 'du -kh /usr/local/bin/healthcheck'
4.0K    /usr/local/bin/healthcheck

Usage

shell nc

1.6. curl

1.6.1. alpine

$ docker run --platform=linux/amd64 --rm alpine:3.21.3 sh -c "apk --no-cache --quiet --no-progress add curl=8.12.1-r0 && ldd /usr/bin/curl | awk '{ print $ 3}' | xargs du -ckshL /usr/bin/curl"
248.0K  /usr/bin/curl
628.0K  /usr/lib/libcurl.so.4
104.0K  /usr/lib/libz.so.1
648.0K  /lib/ld-musl-x86_64.so.1
232.0K  /usr/lib/libcares.so.2
140.0K  /usr/lib/libnghttp2.so.14
196.0K  /usr/lib/libidn2.so.0
76.0K   /usr/lib/libpsl.so.5
780.0K  /usr/lib/libssl.so.3
4.3M    /usr/lib/libcrypto.so.3
700.0K  /usr/lib/libzstd.so.1
56.0K   /usr/lib/libbrotlidec.so.1
1.6M    /usr/lib/libunistring.so.5
140.0K  /usr/lib/libbrotlicommon.so.1
9.8M    total

1.6.2. debian

$ docker run --platform=linux/amd64 --rm debian:12.9-slim sh -c "apt-get -qq update && apt-get -qq install -y curl=7.88.1-10+deb12u8 >/dev/null 2>&1 && ldd /usr/bin/curl | awk '{ print $ 3}' | xargs du -ckshL /usr/bin/curl"
276K    /usr/bin/curl
696K    /lib/x86_64-linux-gnu/libcurl.so.4
120K    /lib/x86_64-linux-gnu/libz.so.1
1.9M    /lib/x86_64-linux-gnu/libc.so.6
188K    /lib/x86_64-linux-gnu/libnghttp2.so.14
196K    /lib/x86_64-linux-gnu/libidn2.so.0
120K    /lib/x86_64-linux-gnu/librtmp.so.1
256K    /lib/x86_64-linux-gnu/libssh2.so.1
76K     /lib/x86_64-linux-gnu/libpsl.so.5
676K    /lib/x86_64-linux-gnu/libssl.so.3
4.6M    /lib/x86_64-linux-gnu/libcrypto.so.3
332K    /lib/x86_64-linux-gnu/libgssapi_krb5.so.2
372K    /lib/x86_64-linux-gnu/libldap-2.5.so.0
64K     /lib/x86_64-linux-gnu/liblber-2.5.so.0
748K    /lib/x86_64-linux-gnu/libzstd.so.1
48K     /lib/x86_64-linux-gnu/libbrotlidec.so.1
1.8M    /lib/x86_64-linux-gnu/libunistring.so.2
2.1M    /lib/x86_64-linux-gnu/libgnutls.so.30
288K    /lib/x86_64-linux-gnu/libhogweed.so.6
312K    /lib/x86_64-linux-gnu/libnettle.so.8
520K    /lib/x86_64-linux-gnu/libgmp.so.10
868K    /lib/x86_64-linux-gnu/libkrb5.so.3
180K    /lib/x86_64-linux-gnu/libk5crypto.so.3
20K     /lib/x86_64-linux-gnu/libcom_err.so.2
52K     /lib/x86_64-linux-gnu/libkrb5support.so.0
112K    /lib/x86_64-linux-gnu/libsasl2.so.2
136K    /lib/x86_64-linux-gnu/libbrotlicommon.so.1
1.3M    /lib/x86_64-linux-gnu/libp11-kit.so.0
84K     /lib/x86_64-linux-gnu/libtasn1.so.6
24K     /lib/x86_64-linux-gnu/libkeyutils.so.1
60K     /lib/x86_64-linux-gnu/libresolv.so.2
44K     /lib/x86_64-linux-gnu/libffi.so.8
19M     total

1.7. wget

1.7.1. alpine

$ docker run --platform=linux/amd64 --rm alpine:3.21.3 sh -c "apk --no-cache --quiet --no-progress add wget=1.25.0-r0 && ldd /usr/bin/wget | awk '{ print $ 3}' | xargs du -ckshL /usr/bin/wget"
404.0K  /usr/bin/wget
696.0K  /usr/lib/libpcre2-8.so.0
196.0K  /usr/lib/libidn2.so.0
780.0K  /usr/lib/libssl.so.3
4.3M    /usr/lib/libcrypto.so.3
104.0K  /usr/lib/libz.so.1
648.0K  /lib/ld-musl-x86_64.so.1
1.6M    /usr/lib/libunistring.so.5
8.7M    total

1.7.2. debian

$ docker run --platform=linux/amd64 --rm debian:12.9-slim sh -c "apt-get -qq update && apt-get -qq install -y wget=1.21.3-1+b2 >/dev/null 2>&1 && ldd /usr/bin/wget | awk '{ print $ 3}' | xargs du -ckshL /usr/bin/wget"
528K    /usr/bin/wget
616K    /lib/x86_64-linux-gnu/libpcre2-8.so.0
36K     /lib/x86_64-linux-gnu/libuuid.so.1
196K    /lib/x86_64-linux-gnu/libidn2.so.0
312K    /lib/x86_64-linux-gnu/libnettle.so.8
2.1M    /lib/x86_64-linux-gnu/libgnutls.so.30
120K    /lib/x86_64-linux-gnu/libz.so.1
76K     /lib/x86_64-linux-gnu/libpsl.so.5
1.9M    /lib/x86_64-linux-gnu/libc.so.6
1.8M    /lib/x86_64-linux-gnu/libunistring.so.2
1.3M    /lib/x86_64-linux-gnu/libp11-kit.so.0
84K     /lib/x86_64-linux-gnu/libtasn1.so.6
288K    /lib/x86_64-linux-gnu/libhogweed.so.6
520K    /lib/x86_64-linux-gnu/libgmp.so.10
44K     /lib/x86_64-linux-gnu/libffi.so.8
9.7M    total

2. Development

2.1. Format Source Code

$ scripts/format.sh

2.2. Lint Source Code

$ scripts/lint.sh

3. Development Environment Setup

❗	After cloning this repository, you need to install the Git hooks and configure the ignore-revs-file: $ git config set core.hooksPath .githooks $ git config set blame.ignoreRevsFile .git-blame-ignore-revs

3.1. Installation

3.1.1. Docker

Install Docker.

3.1.2. easyrsa

❗	Ensure that you install version 3.1.7 and not 3.2.x!

Linux

Install easyrsa.

Mac

⚠️	Unfortunately, homebrew provides easy-rsa version 3.2.x .

$ curl -L https://github.com/OpenVPN/easy-rsa/releases/download/v3.1.7/EasyRSA-3.1.7.tgz -o ~/Downloads/easy-rsa.tgz
$ tar -xzf ~/Downloads/easy-rsa.tgz -C ~/.local/share
$ mv  ~/.local/share/EasyRSA-3.1.7 ~/.local/share/easyrsa
$ ln -s ~/.local/share/easyrsa/easyrsa ~/.local/bin/easyrsa
$ rm ~/Downloads/easy-rsa.tgz

3.1.3. Go

Install Go.

3.1.4. golangci-lint

Install golangci-lint.

3.1.5. hadolint

Linux

Install hadolint.

Mac

$ brew install hadolint

3.1.6. JDK

There are several different JDKs and multiple options for installing them.

The recommended way is to install via SDKMAN!:

$ sdk install java

More Information

SDKMAN JDKs

3.1.7. Node Version Manager

Install fnm or NVM.

fnm

~/.zprofile

if command -v fnm > /dev/null 2>&1; then
  eval "$(fnm env --use-on-cd)"
fi

nvm

~/.zshrc

export NVM_DIR="${HOME}/.nvm"

[ -s "${NVM_DIR}/nvm.sh" ] && . "${NVM_DIR}/nvm.sh"
[ -s "${NVM_DIR}/bash_completion" ] && . "${NVM_DIR}/bash_completion"

if command -v nvm > /dev/null 2>&1; then
  autoload -U add-zsh-hook
  load-nvmrc() {
    local nvmrc_path="$(nvm_find_nvmrc)"
    if [ -n "${nvmrc_path}" ]; then
      local nvmrc_node_version=$(nvm version "$(cat "${nvmrc_path}")")
      if [ "${nvmrc_node_version}" = "N/A" ]; then
        nvm install
      elif [ "${nvmrc_node_version}" != "$(nvm version)" ]; then
        nvm use
      fi
    elif [ -n "$(PWD=$OLDPWD nvm_find_nvmrc)" ] && [ "$(nvm version)" != "$(nvm version default)" ]; then
      echo "Reverting to nvm default version"
      nvm use default
    fi
  }

  add-zsh-hook chpwd load-nvmrc
  load-nvmrc
fi

3.1.8. Rust

Install Rust.

$ curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y --default-toolchain stable --component rust-analyzer

3.1.9. shellcheck

Linux

$ sudo apt-get install shellcheck

Mac

$ brew install shellcheck

3.1.10. shfmt

Linux

$ sudo apt-get install shfmt

Mac

$ brew install shfmt

3.1.11. yamllint

Linux

$ sudo apt-get install yamllint

Mac

$ brew install yamllint