Generating the Client Assertion JWT for private_key_jwt Authentication with Ruby (1 mins read).
A helper script to generate the client assertion required to authenticate to an Authorization Server that supports private_key_jwt, on the command-line with Ruby.
by 
Jamie Tanna
.
#blogumentation
#ruby
#command-line
#jwt
#json
#oidc.
Verifying Signed JWTs (JWS) with Ruby (2 mins read).
Using the ruby-jwt library to verify a signed JSON Web Token (JWS) on the command-line.
by Jamie Tanna
.
#blogumentation
#ruby
#command-line
#jwt
#json.
Creating Signed JWTs (JWS) with Ruby (1 mins read).
Using the json-jwt and ruby-jwt libraries to sign a JSON Web Token on the command-line.
by Jamie Tanna
.
#blogumentation
#ruby
#command-line
#jwt
#json.
Why You Should Write a CLI Tool for Your Organisation
Recommended read: Why You Should Write a CLI Tool for Your Organisation https://www.surminus.com/blog/why-you-should-write-a-cli-tool-for-your-org/
Is `sudo` almost useless? - Information Security Stack Exchange
Recommended read: Is `sudo` almost useless? - Information Security Stack Exchange https://security.stackexchange.com/questions/232924/is-sudo-almost-useless
by Jamie Tanna
.
#sudo
#linux
#command-line.
How to Run Java on the Command-Line to Attach a Debugger (1 mins read).
How to run java on the command-line, and make it possible to attach a debugger.
Anna Dodson and I had good fun a couple of years ago with https://github.com/veltman/clmystery and https://overthewire.org/wargames/
by Jamie Tanna
.
#linux
#command-line.
Converting Output from Rest Assured to Curl Requests (3 mins read).
How to convert the log output from Rest Assured to a curl request.
by Jamie Tanna
.
#blogumentation
#rest-assured
#command-line.
How to convert a SVG to a PNG with ImageMagick? - Stack Overflow
Recommended read: How to convert a SVG to a PNG with ImageMagick? - Stack Overflow https://stackoverflow.com/questions/9853325/how-to-convert-a-svg-to-a-png-with-imagemagick#14174624
by Jamie Tanna
.
#command-line.
Take care editing bash scripts
Recommended read: Take care editing bash scripts https://thomask.sdf.org/blog/2019/11/09/take-care-editing-bash-scripts.html
Determining What Motherboard You're Using, On Linux (1 mins read).
How to determine what motherboard the machine you're using is reporting, on the command-line with Linux.
jq - my new favorite tool to work with json on the command line
Recommended read: jq - my new favorite tool to work with json on the command line https://200ok.ch/posts/jq-my-new-favorite-tool-to-work-with-json-on-the-command-line.html
by Jamie Tanna
.
#command-line
#json.
Toggling Your Bluetooth Connection using bluetoothctl on the Command-Line (1 mins read).
How to script bluetoothctl to toggle your connection to a Bluetooth device.
by Jamie Tanna
.
#blogumentation
#command-line
#bluetoothctl.
Ignoring bulk change commits with git blame
Recommended read: Ignoring bulk change commits with git blame https://www.moxio.com/blog/43/ignoring-bulk-change-commits-with-git-blame
by Jamie Tanna
.
#command-line
#git.
A great addition for those scripting with curl!
Recommended read: curl write-out JSON https://daniel.haxx.se/blog/2020/03/17/curl-write-out-json/
by Jamie Tanna
.
#command-line.
Splitting an X509 PEM-Encoded Certificate Bundle into Multiple Files (1 mins read).
Splitting a certificate bundle into separate files using split or awk.
by Jamie Tanna
.
#blogumentation
#command-line
#certificates.
The growth of command line options, 1979-Present
Recommended read: The growth of command line options, 1979-Present https://danluu.com/cli-complexity/
by Jamie Tanna
.
#command-line
#linux
#unix.
How to Use curl to Send Requests to Domains Without Editing Your /etc/hosts File (1 mins read).
Using curl's --resolve flag to perform custom lookup for hosts.
Triggering an AWS Lambda from the Command-Line (1 mins read).
How to invoke an AWS Lambda function from the Command-Line.
Generating HMAC Signatures on the Command Line with OpenSSL (1 mins read).
How to generate HMAC signatures for a given string, using openssl.
by Jamie Tanna
.
#blogumentation
#command-line
#openssl
#hmac
#java.
Creating Signed JWTs (JWS) with Node.JS (1 mins read).
How to use the jsonwebtoken library to create a Signed JSON Web Token (JWS) with Node.JS.
by Jamie Tanna
.
#blogumentation
#nodejs
#command-line
#jwt
#json.
AWS CLI v2 is now generally available
Recommended read: AWS CLI v2 is now generally available https://aws.amazon.com/blogs/developer/aws-cli-v2-is-now-generally-available/
by Jamie Tanna
.
#command-line
#aws.
Anybody can write good bash (with a little effort)
I used to write a lot of shell scripts before realising that what I was trying to do was treat shell scripting as a "full" scripting language (I won't define here what I mean by "full").
Its not - reach for a higher level scripting language like Ruby or Python when things are getting more complicated, and allow shell scripts to glue things together, or be for quick tasks maybe a few lines long.
When you do write them, this advice is great but it's definitely worth gaining understanding of when you should and shouldn't use them.
Recommended read: Anybody can write good bash (with a little effort) https://blog.yossarian.net/2020/01/23/Anybody-can-write-good-bash-with-a-little-effort
by Jamie Tanna
.
#command-line
#shell
#bash.
Big list of http static server one-liners
Recommended read: Big list of http static server one-liners https://gist.github.com/willurd/5720255
by Jamie Tanna
.
#command-line
#http.
Parsing a Unix Epoch With Bash/Ruby on the Command-Line (1 mins read).
How to convert a Unix Epoch to a human-readable date format.
by Jamie Tanna
.
#blogumentation
#command-line
#ruby
#shell.
What You Probably Didn’t Know About Sudo
Very interesting to see that there's even more to the command than expected - and some great new features coming soon.
Recommended read: What You Probably Didn’t Know About Sudo https://aster.cloud/2019/12/17/what-you-probably-didnt-know-about-sudo/
by Jamie Tanna
.
#command-line.
Recommended read: A quick primer on dig https://mrkaran.dev/posts/dig-overview/
by Jamie Tanna
.
#dns
#command-line.
Pretty Printing XML on the Command-Line (1 mins read).
How to use xmllint to pretty-print XML/HTML files.
by Jamie Tanna
.
#blogumentation
#html
#xml
#pretty-print
#command-line.
List What Files Changed in a Git Commit (1 mins read).
How to list what files changed in a given commit.
Recommended read: Improving CLIs with isatty https://blog.jez.io/cli-tty/
by Jamie Tanna
.
#command-line.
Recommended read: Beware of shell globs https://soptik.tech/articles/beware-of-shell-globs.html
by Jamie Tanna
.
#shell
#command-line.
Using the OpenSSL Command-Line to Verify an SSL/TLS Connection (2 mins read).
How to use the openssl command-line to verify whether certs are valid.
by Jamie Tanna
.
#blogumentation
#openssl
#certificates
#command-line
#nablopomo.
Pretty Printing YAML with the Ruby Command-Line (1 mins read).
Using Ruby's YAML library to pretty-print YAML files from the command-line.
by Jamie Tanna
.
#nablopomo
#blogumentation
#ruby
#yaml
#pretty-print
#command-line.
This is my go-to for tidying up disk space issues when working with Docker
Recommended read: Docker Cleanup Commands https://www.calazan.com/docker-cleanup-commands/
Piping Data When Not Running a Command with sudo (1 mins read).
How to (more) safely pipe stdin to an elevated command with sudo tee.
by Jamie Tanna
.
#blogumentation
#command-line
#nablopomo
#security.
Minifying JSON with Python (1 mins read).
How to take a pretty-printed JSON string and replace it with a minifed JSON string using Python.
by Jamie Tanna
.
#python
#command-line
#blogumentation
#nablopomo
#json
#minify-json.
Minifying JSON with Ruby (1 mins read).
How to take a pretty-printed JSON string and replace it with a minifed JSON string using Ruby.
by Jamie Tanna
.
#ruby
#command-line
#blogumentation
#nablopomo
#json
#minify-json.
Two shebang papercuts and a thimble
Recommended read: Two shebang papercuts and a thimble https://www.crystae.net/posts/2019/11/08/two-shebang-papercuts/
by Jamie Tanna
.
#linux
#mac
#unix
#command-line.
Analysing webservers logs locally with goaccess
Recommended read: Analysing webservers logs locally with goaccess https://ma.ttias.be/analysing-webservers-logs-locally-with-goaccess/
Safely Creating And Using Temporary Files
This is a great resource to highlight the difficulty of creating temporary files safely - something I've tried to share before but without these great examples.
Its especially bad if using a shared CI/CD server and putting downloaded files into /tmp as you don't know whether it'll be clobbered / stolen by others on the instance
Recommended read: Safely Creating And Using Temporary Files https://www.netmeister.org/blog/mktemp.html
by Jamie Tanna
.
#linux
#command-line.
Recommended read: Unnecessary use of `curl -X` https://daniel.haxx.se/blog/2015/09/11/unnecessary-use-of-curl-x/
by Jamie Tanna
.
#curl
#command-line.
A Linux sysadmin's guide to moving to a new website
Recommended read: A Linux sysadmin's guide to moving to a new website https://ma.ttias.be/sysadmin-guide-move-content-new-website/
Recommended read: Stupid UNIX Tricks https://sneak.berlin/20191011/stupid-unix-tricks/
by Jamie Tanna
.
#command-line
#shell
#linux
#unix
#openssh
#docker
#security.
Use the Unofficial Bash Strict Mode (Unless You Looove Debugging)
This is a great article about how to be safer when writing shell scripts. I am a huge proponent of not using them where possible, and instead moving them to another scripting language (Ruby, Python, Node) which you can test, and use a shared standard library.
Recommended read: Use the Unofficial Bash Strict Mode (Unless You Looove Debugging) http://redsymbol.net/articles/unofficial-bash-strict-mode/
by Jamie Tanna
.
#shell
#command-line.
Adding Newlines to all Files in Git (3 mins read).
Adding newlines at the end of all Git-tracked files.
Easily Parsing Failed Cucumber Scenarios from the JSON Report (2 mins read).
How to parse a Cucumber JSON report to display the failed scenarios and their causes.
by Jamie Tanna
.
#blogumentation
#cucumber
#ruby
#command-line.
Learn a little jq, awk and sed
This is a great post - I thoroughly recommend learning how to use common commandline tools such as awk, grep, sed, but also adopting a scripting language for more complicated stuff. I don't mean Bash, or another shell scripting language, but something like Node, Python or Ruby, as it'll give you the opportunity for a greater standard library, as well as tonnes of packages built by others.
Recommended read: Learn a little jq, awk and sed https://letterstoanewdeveloper.com/2019/07/29/learn-a-little-jq-awk-and-sed/
by Jamie Tanna
.
#command-line.
Pretty Printing JSON Files Inline on the Command Line (2 mins read).
How to rewrite multiple JSON files inline on the Command Line.
by Jamie Tanna
.
#blogumentation
#pretty-print
#command-line
#ruby.
Pretty Printing JSON Web Tokens (JWTs) on the Command Line using OpenSSL (3 mins read).
How to easily introspect a JWT on the command line using OpenSSL and optionally Python for real pretty-printing.
by Jamie Tanna
.
#blogumentation
#python
#command-line
#jwt
#json
#pretty-print.
https://www.vidarholen.net/contents/blog/?p=746
In every programming language, there is a linting tool that can help pick up on some common style issues. ShellCheck isn't one of those - it's so much more!
I've been using it for many years now, and since it came into my life it's honestly changed the way I use shell scripts. There have been so many pitfalls that I've avoided falling into since learning about them (and adding ShellCheck to my Vim linting setup.
This is a great read from Vidar, the ShellCheck author, about a case where it could've caught issues that caused the deletion of a production database!
Recommended read: https://www.vidarholen.net/contents/blog/?p=746 https://www.vidarholen.net/contents/blog/?p=746
by Jamie Tanna
.
#shell
#command-line.
URL Decoding with Ruby on the Command Line (1 mins read).
How to use Ruby's standard library to decode URLs with a handy one-liner.
Viewing X.509 DER Certificate Fingerprints with OpenSSL (1 mins read).
How to view an X.509 DER certificate's fingerprint using openssl commands.
by Jamie Tanna
.
#blogumentation
#certificates
#command-line
#der
#openssl.
Viewing X.509 PEM Certificate Fingerprints with OpenSSL (1 mins read).
How to view an X.509 PEM certificate's fingerprint using openssl commands.
by Jamie Tanna
.
#blogumentation
#certificates
#command-line
#pem
#openssl.
Verifying Signed JWTs (JWS) with Node.JS (3 mins read).
How to use the jsonwebtoken and node-jose libraries to verify the signature of a Signed JSON Web Token (JWS) with Node.JS.
by Jamie Tanna
.
#blogumentation
#nodejs
#command-line
#jwt
#json.
Setting your default AWS profile for the AWS CLI and SDKs (2 mins read).
Setting the default AWS profile when working with multiple profiles and the AWS CLI / SDKs.
by Jamie Tanna
.
#blogumentation
#aws
#aws-cli
#aws-sdk
#command-line.
Viewing X.509 DER Certificate Details with OpenSSL (2 mins read).
How to convert an X.509 DER file to a human-readable format using openssl commands.
by Jamie Tanna
.
#blogumentation
#certificates
#command-line
#der
#openssl.
Viewing X.509 PEM Certificate Details with OpenSSL (2 mins read).
How to convert an X.509 PEM file to a human-readable format using openssl commands.
by Jamie Tanna
.
#blogumentation
#certificates
#command-line
#pem
#openssl.
Safely Force Pushing with Git using --force-with-lease=ref (6 mins read).
How git push --force-with-lease=ref can save you from overriding others' changes on shared Git branches.
My editorial workflow for blog posts (8 mins read).
Taking you through the journey I go on when writing blog posts, from ideation to publishing the post.
by Jamie Tanna
.
#www.jvt.me
#workflow
#ci
#gitlab
#git
#automation
#command-line
#shell
#gitlab-ci
#review-apps.
Viewing Git history of a file in git log while ignoring file renames (5 mins read).
How to track changes to files in Git without pesky file renames getting in the way, using git log --follow.
Pretty Printing JSON Web Tokens (JWTs) on the Command Line using Ruby (3 mins read).
How to easily introspect and pretty print a signed JWT (JWS) or an encrypted JWT (JWE) on the command line using Ruby's standard library, or using the ruby-jwt external library.
by Jamie Tanna
.
#blogumentation
#ruby
#command-line
#jwt
#json
#pretty-print.
Merging multiple repositories into a monorepo, while preserving history, using git subtree (3 mins read).
How to merge multiple repositories, with their history, into a single repository, using the git subtree add command.
by Jamie Tanna
.
#blogumentation
#git
#monorepo
#git-subtree
#command-line.
Sharing Multiple SSH Sessions over the Same Network Socket (3 mins read).
Reusing network sockets for speed and reduction of authentication handshakes with OpenSSH.
by Jamie Tanna
.
#blogumentation
#ssh
#openssh
#command-line.
Better Git Diff Outputs with Git Submodules (2 mins read).
How to get nicer diffs when working with submodules.
Executing an Interactive Python Shell (REPL) for a Script (1 mins read).
Using python -i to get an interactive REPL after running a Python source file.
by Jamie Tanna
.
#command-line
#python
#blogumentation
#tools
#howto.
SSLError When Running Berkshelf Behind a Proxy (2 mins read).
Getting around the pesky OpenSSL::SSL::SSLError SSLv2/v3 read server hello A error when running Berkshelf behind a proxy.
by Jamie Tanna
.
#chef
#blogumentation
#proxy
#command-line
#shell
#chefdk
#berkshelf.
Converting YAML to JSON and vice versa (Part 1 - Ruby) (2 mins read).
Coerce YAML to JSON and vice versa, from the comfort of your Gem-studded command line.
by Jamie Tanna
.
#blogumentation
#ruby
#command-line
#yaml
#json.
glances, a top and htop replacement (1 mins read).
I share the tool I have been using for system utilisation and monitoring, glances.
by Jamie Tanna
.
#blogumentation
#command-line
#python
#tool
#workflow.