zap VS pgx

The project currently uses slog package from standard library for logging. But switching to a more advanced logger like zap could offer more flexibility and features.

It's nice to have this in the standard library, but it doesn't solve any existing pain points around structured log metadata and contexts. We use zap [0] and store a zap logger on the request context which allows different parts of the request pipeline to log with things like tenantid, traceId, and correlationId automatically appended. But getting a logger off the context is annoying, leads to inconsistent logging practices, and creates a logger dependency throughout most of our Go code.

[0] https://github.com/uber-go/zap

Kubebuilder, like much of the k8s ecosystem, utilizes zap for logging. Out of the box, the Kubebuilder zap configuration outputs a timestamp for each log, which gets formatted using scientific notation. This makes it difficult for me to read the time of an event just by glancing at it. Personally, I prefer ISO 8601, so let's change it!

What else would you expect from a structured logging package?

To me it absolutely makes sense as the default and standard for 99% of applications, and the API isn't much unlike something like Zap[0] (a popular Go structured logger).

The attributes aren't an "arbitrary" concept, they're a completely normal concept for structured loggers. Groups are maybe less standard, but reasonable nevertheless.

I'm not sure if you're aware that this is specifically a structured logging package. There already is a "simple" logging package[1] in the sodlib, and has been for ages, and isn't particularly fast either to my knowledge. If you want really fast you take a library (which would also make sure to optimize allocations heavily).

[0]: https://pkg.go.dev/go.uber.org/zap

[1]: https://pkg.go.dev/log

And finally for structured logging: https://github.com/uber-go/zap

For logging: I recommend using Uber Zap https://github.com/uber-go/zap It will log stack backtraces and makes it super easy to debug errors when deployed. I typically log in the business logic and not below. And log at the entry for failures to start the system. Maybe not necessary for this example, but it’s an essential piece of any API backend.

Sometimes, backend developers tend to opt for an ORM library because it provides an abstraction between your app and the database and thus there is little or no need to write raw queries and migrations which is nice. However, if you want to get better at writing queries (SQL for example), you need to learn how to build your repositories without an ORM. To open a database handle, you can either do it directly from the database driver or do it from database/sql with the driver passed into it. I will be opening the connection with database/sql together with pgx which is a driver and toolkit for PostgreSQL. Walk with me.

The infrastructure layer contains the concrete implementation of the repository domain interface ActivityRepository in the struct DbActivityRepository. This repository implementation uses the Postgres driver pgx and plain SQL to store the activity in the database. It uses the database transaction from the context, since the transaction was initiated by the application service.

For building the RESTful Point of Sale service API, I've considered and selected a combination of technologies that would work seamlessly together. For handling HTTP requests and responses, using the Gin HTTP web framework would make sense because I think it seems complete and popular among Go community too. To ensure data integrity and persistence, I'm using PostgreSQL database with pgx as the database driver, the reason I choose PostgreSQL because it is the most popular relational database to use in production and offers efficient Go integration. I'm also implementing caching using Redis with go-redis client library, which provides powerful in-memory data storage capabilities.

If you are willing to commit to working only with Postgres, I highly recommend pgx. Be sure you get the latest version github.com/jackc/pgx/v5. This gives you the full power of interacting with Postgres without going through an intermediate lowest-common-denominator library.

It uses pg package and pgx driver under the hood.

Starting off, is there any reason you're calling out to the CLI, instead of just using a Postgres driver like pgx? Shelling out to the command line should always be a last resort where possible as a software engineer.

For maintaining state I use PostgreSQL. Driver: https://github.com/jackc/pgx (I use the pgxpools) Along with Sqlc for generating database models and allowing me to focus on just building queries in DBeaver. https://sqlc.dev/

An example of what I'm looking for can be found here https://github.com/jackc/pgx/wiki/Getting-started-with-pgx-through-database-sql/c9f798b4d9a500fcf93931df2464af969d68f516

Except pgx recommends using their native interface, not database/sql, for performance and extra features [0], so it's not that simple in practice.

[0]: https://github.com/jackc/pgx#choosing-between-the-pgx-and-da...

pgx is “PostgreSQL driver and toolkit for Go”. Take a look at https://github.com/jackc/pgx