Programming on melastmohican.github.io

Rusty Feather

Mon, 14 Nov 2022 14:27:13 -0800

Recently I stumbled upon info about using Rust language on embedded systems including microcontrollers. I searched for some tutorials and online trainings and it seems like you need specific hardware usually. Getting STM32F3DISCOVERY or nRF52840 DK is not practical because I will have limited use for these boards after completing training. I was almost willing to get micro:bit when I found out that Ferrous Systems and Espressif’s announced Rust Training on ESP32.

ESP Rust Board Link to heading

It is officially called ESP32-C3-DevKit-RUST-1 if you want to search for it. The board is based on successful ESP32-C3-MINI-1 module and has 6DoF IMU (ICM-42670-P), a temperature and humidity sensor (SHTC3), a Li-Ion battery charger, and a Type-C USB in familiar Adafruit Feather format. It is pretty close to Adafruit ESP32-S2 Feather with BME280 Sensor minus Stemma connector but with IMU sensor instead.

ESP32-C3-DevKit-RUST-1

Convert Kafka JKS certificate to PEM

Sat, 14 Mar 2020 21:35:50 -0700

Intro Link to heading

Kafka supports encryption and authentication via SSL. However, the generated certificates are in Java KeyStore (JKS) format so if you need to use them in other language you need to convert them to X.509 format (.pem – Privacy-enhanced Electronic Mail).

Here are the commands to extract the Certificate Authority (CA) certificate:

$ keytool -importkeystore -srckeystore dev.client.truststore.jks -destkeystore server.p12 -deststoretype PKCS12
$ openssl pkcs12 -in server.p12 -nokeys -out ca_cert.pem

You can then convert your client keystore to be usable from languages supporting .pem, with similar commands:

What new language should I learn as Java Developer

Fri, 13 Mar 2020 05:38:17 -0800

If you are a Java programmer and are thinking of learning some more programming languages to expand your knowledge and skills, but not sure which programming languages to choose, then you are not alone. Last year there were multiple talks in our organization about migrating away from Java because o potential problems with new Oracle licensing. It is still unclear how Oracle will be auditing for Java licensing and what it will mean should an organization not be compliant. We switched to a different OpenJDK vendor and we are using Amazon Correto now. We also migrated all ouf our microservices from Java 8 to 11 for a different reason which I might mention later.