A simple utility to generate and decode JSON Web Tokens (JWTs) that can be used to authenticate against web applications. The code is released under the Apache 2 Open Source License. See JWT-OPA for an example of how JWTs can be used to authenticate/authorize access to protected online resources/applications. Usage Use –help (or -h) for … More JSON Web Tokens (JWT) utilities
We present a Java library that simplifies adopting the Open Policy Agent server to manage user authorization for a Spring Boot microservice, while also managing API Token (JWT) authentication. Motivation Spring Security assumes a fairly simplistic Role-Based access control (RBAC) where the service authenticates the user (via some credentials, typically username/password) and returns a UserDetails … More Integrating Open Policy Agent with Spring Security Reactive and JSON Web Tokens
The Envelope Wrapper pattern This pattern, described in “Enterprise Integration Patterns” (Ch. 8, “The Envelope Wrapper”), is used typically in messaging systems, when a number of metadata fields (for routing, security, etc.) are kept in a header, while the data used by service endpoints is serialized in a payload. For the system to be generically … More Implement the Envelope Wrapper Pattern in C++ using Google Protocol Buffers
With the relatively recent change in the frequency of Java releases (every six months) it has become pretty much required to be able to have multiple JDKs on one’s development machine, and being able to run/test them at different times, for different projects, or even for the same project. Motivation While some wizardry with symlinks … More Support multiple JDKs in Debian Linux
There is something to be said for the immediacy of using Bash scripts, especially when dealing with relatively simple system operations; however, parsing command line arguments has always been rather cumbersome and usually done along the lines of painful if [[ ${1} == ‘–build’ ]]; then …. On the other hand, Python is pretty convenient … More Parse Args in Bash Scripts
Merkle Trees store a hash of the sub-tree in each of the Nodes, so that the whole tree’s contents can be validated against tampering.They are used, for example, in Bitcoin’s blockchain, and in Cassandra to validate replicas.In this article, we will show how to implement a generic Merkle Tree using features of Modern C++. Previous … More Modern C++: Implementing a Merkle Tree
The STL provides a high-performance queue class in std::queue<T>; however, the API is not very intuitive, or easy, to use and it is not safe to access from multiple threads.In this article, we will show how to wrap it in a more convenient, and thread-safe, API. The C++ Standard Template Library (STL) offers a template-class … More Modern C++: Writing a thread-safe Queue
Honestly, it should be easier – then again, it’s Gnome, nothing really is easy. Collecting a combination of various pages (this one finally yielded the right directions) it turns out one has to install imwheel and then adjust the ~/.imwheelrc file: The magic incantation is in the first couple of lines and the value (3 … More Ubuntu: adjust mouse scroll wheel sensitivity
Almost four years after its initial inception and release, I have entirely rewritten the CLI invocation, streamlined the encryption secrets management, and created a self-contained executable. Once you have a private/public key pair, a file can be simply encrypted using: ./filecrypt.pyz -o my_file.enc /path/to/plain.txt and decrypted using: ./filecrypt.pyz -o /path/to/plain.txt -d my_file.enc The –send option … More filecrypt — OpenSSL-based file encryption, release 0.7.2
In MacOS the command to emit data about battery status is: pmset -g batt If you want to record the battery percentage level in a file at regular intervals, here is how to record the data in a one-liner: while true; do \ echo “$(date “+%Y-%m-%d %H:%M:%S”) ” \ “$(pmset -g batt | grep “%” … More How to emit battery data in a one-liner on MacOS
