Simser

Simple serialization code generator for GO structs with unexported fields.

Like binary.Read, but a bit different and without reflection.

Features

Core

• go module mode only
• simple sequential [de]serialization of simple structs
• supports non-exported fields, as well as exported
• basic (int32, float64, etc.), named (type My uint64, etc.) field types, and arrays of them (struct type fields, array of arrays and slice of arrays are not supported right now)
• no reflection in generated code, it is simple and fast
• possibility to select type[s] to serialize via -types CLI flag
• customize output function names
• customize output file name

Advanced

• slice field length can be set to any expression that returns int, by using tags. Currently [de]serialized instance can be referred to as "o", within expression.
  E.g. simser:"len=o.PreviousIntegerField-5".
  Or simser:"len=otherFunc()"
  Remember that only fields that get read before the slice field will have meaningful values (unless some tricks were used)

Usage

Basic

//go:generate go run github.com/amanofbits/simser -types=Header,body //go:generate go run github.com/amanofbits/simser -types=all

• -types (required): can be a comma-separated list of types you want to process, or reserved keyword all for processing all top-level structs, found in file.
  all usage and requiredness of the argument can change in the future.
• -output (optional): set output file name.

Custom

//go:generate go run github.com/amanofbits/simser -types=Header -output=file.name -read-fn-name=customReadFnName -write-fn-name=CustomWriteFnName

• -read-fn-name (optional): custom name for deserializing function. Is set per-file.
• -write-fn-name (optional): custom name for deserializing function. Is set per-file.

Project state

A bit messy, not very optimal, but simple and working. It was developed quickly from scratch, to serve a particular practical purpose, so the code itself is rather not perfect, but generated code should be good and do the job.
It's the first time I worked with go's ast, so it was a lot of try-and-fail behind the scenes. Feel free to file issues.

TODOs

• add field skipping (skip, rskip, wskip tags)
• add _ fields support (don't assign them on read, just skip n bytes; write customizable padding byte instead)
• add ability to select only r or w functions with flags like -r[=customFnName], -w[=customFnName]