GJSON VS pgx

Someone made a benchmark of serialization libraries in go [1], and I was surprised to see gobs is one of the slowest ones, specially for decoding. I suspect part of the reason is that the API doesn't not allow reusing decoders [2]. From my explorations it seems like both JSON [3], message-pack [4] and CBOR [5] are better alternatives.

By the way, in Go there are a like a million JSON encoders because a lot of things in the std library are not really coded for maximum performance but more for easy of usage, it seems. Perhaps this is the right balance for certain things (ex: the http library, see [6]).

There are also a bunch of libraries that allow you to modify a JSON file "in place", without having to fully deserialize into structs (ex: GJSON/SJSON [7] [8]). This sounds very convenient and more efficient that fully de/serializing if we just need to change the data a little.

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1: https://github.com/alecthomas/go_serialization_benchmarks

2: https://github.com/golang/go/issues/29766#issuecomment-45492...

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3: https://github.com/goccy/go-json

4: https://github.com/vmihailenco/msgpack

5: https://github.com/fxamacker/cbor

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6: https://github.com/valyala/fasthttp#faq

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7: https://github.com/tidwall/gjson

8: https://github.com/tidwall/sjson

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I don't think there is a way to sort an array, though. However, there is an option to have keys sorted. Personally, I don't think there is much annoyance in that. One could just pipe `jj` output to `sort | uniq -c`.

[0]: https://github.com/tidwall/gjson/blob/master/SYNTAX.md

I’m using GJSON, so far so good!

If the fields you need are just a small subset of the whole json, maybe https://github.com/tidwall/gjson might be of use to read only those (using jsonpath) without needing to create complete corresponding structs.

Thank you for the reminder, it's never too much of it :) Didn't say it, but the code was pprof-iled many times and i can really say it's well optimized. I use own libraries with on-the-fly equations (sums, avgs, emas, stds, ...) wherever possible and also made custom json parser as json messages are in fixed format, so the parser is about 10x faster than gjson. I optimized it to the point that I avoided using maps, and rather iterate via slice where ever possible.

You are right, for learning purposes this fit my needs, but I can imagine an approach similar to this repo: https://github.com/tidwall/gjson

https://github.com/tidwall/gjson is a relatively sensible library if this is something you need to deal with and the structure is actually unknowable.

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