Practical example demonstrating how to query for min/max values of grouped documents in MongoDB including additional non-grouped field values using $push
, $map
and $filter
aggregation operators.
tsmx-dev
MongoDB: add/update fields referencing other existing fields using aggregation pipelines
Short explanation on how to add or update fields in documents referencing the values of other already existing fields by leveraging the aggregation pipeline framework.
Connecting from a Docker container to a local MongoDB
A quick guide demonstrating how to connect to a local MongoDB instance from a Docker container.
Full code-coverage with Jest
A guided tour on how to achieve the most complete code-coverage with Jest in your NodeJS projects and an some thoughts on why this is not necessarily the primary target.
Creating a time series sample CSV file with a bash script
Demonstrating a pragmatic way for generating time series sample data in CSV files with a bash script. Useful for Proof-of-Concepts, unit and performance testing and many other scenarios.
npm major package upgrades with backward patch support
A short checklist for publishing new major versions of your packages in the npm registry including support for patching older versions.
Testing process.exit with Jest in NodeJS
Demonstrating a pragmatic way on how to test code paths resulting in process.exit
using the Jest test library.
Commander options hands-on – advanced CLI’s with NodeJS
The Commander package is a great utility for building a CLI with NodeJS. This article provides a comprehensive hands-on for the various option features of Commander.
JavaScript Map: sorted for-loop with a custom iterator
An elegant way of how to do a sorted iteration over all entries of a JavaScript Map with a for-loop using a custom iterator implemented with Symbol.iterator
, function*
and yield*
.
Express: middleware function with custom parameters
Implementing an Express middleware function that can handle custom parameters.