Category Archives: Programming

DDD/Clean Architecture go linters

Origin (in Russian) Tech talk (paid access only, unfortunately): Presentation: Linters Dependencies between layers: Others: — to check using all microtypes in enums/switches. + — to prevent using struct tags in Domain models (Value Objects). — to prevent changing Value Objects (Domain models) from outside of the …

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Protobuf: safer usage for buf

A drop-in replacement for buf issued by Ozon. Repository: Presentation (for subscribers only, unfortunately):

Maps internals in Go

Idea Map is passed as a value, but it consists of a pointer to hmap which has all the details on map implementation. So, if you change/add to map, it will be reflected everywhere. And that’s why you cannot assign to an uninitialized map (no memory allocated, no hash seed generated yet). runtime/map.go

Buckets …

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Docker and Kubernetes basics for developers

Docker Docker containers are much more lightweight compared to classic VMs as they leverage host OS instead of starting their own OS. Containers are using 2 features of Linux-based OS: Namespaces and Cgroups (Control Groups). Namespace Lets you allocate resources in an isolated environment (like a sandbox). On a container start, docker daemon generates a …

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Go’s Concurrency and Channel Internals

Go is implementing CSP (Communicating Sequential Processing): processes are communicating through channels, they can block each other while waiting for read/writes to channels. Actor model makes inter-process communications more explicit and non-blocking. CSP vs Actor explained — Channels requirements goroutine-safe store and pass data across goroutines FIFO can block/unblock goroutines

Protobuf: add header parameters

They finally added it to the grpc-gateway: So, to use it you can just update to the version 2.14.0 or above —, and add something like this to your protofile:

Go scheduler details

Scheduler was implemented by Dmitry Vyukov in go 1.1 and lives in runtime/proc.go. Good resources — video by Dmitry Vyukov (slides as pdf) — nice article by Bill Kennedy in 3 parts. Most of the images below are taken from this article. Main ideas Goroutines are very light weight (~2KB+) and very cheap …

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Golang. Adding a json body to POST request in protofile

It could be a bit tricky, and I failed to find a good example for it.

Mock sql (sqlx) db on golang

I am using this library — That’s how you can use it for mocking db querying:

How to install multiple versions of go on mac m1

For instance, I want to try a new beta, go1.18beta2 (I check if it’s available on the download page). And I already have a regular go1.17, that I want to use as a default one. To do so, I need to do this:

Then I can check if it’s okay — go1.18beta2 version #go …

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