forego

forego

Build Go JSON/WebSocket services with tagged logging, auto-wired APIs, and test-first ergonomics.

Why Forego

• Tagged JSON logs keep every request’s story without coupling handlers to a logger. Attach tags with ctx.WithTag, and ctx/log takes care of consistently emitting them.
• The http, api, and test packages form a feedback loop: define a Go struct once, expose it over HTTP/WebSocket, and exercise it in your tests without binding boilerplate.
• Batteries stay optional. Supporting packages like enc, shutdown, and utils/prom plug in when you need them without locking you into a monolith.

Quickstart

1. Install the module:

   go get github.com/ohait/forego@latest
   

2. Wire an API, HTTP server, and graceful shutdown:

   package main
   
   import (
       "regexp"
   
       fctx "github.com/ohait/forego/ctx"
       flog "github.com/ohait/forego/ctx/log"
       fhttp "github.com/ohait/forego/http"
       "github.com/ohait/forego/shutdown"
   )
   
   type WordFilter struct {
       Blacklist *regexp.Regexp
   
       In  string `api:"in,required"`
       Out string `api:"out"`
   }
   
   func (wf *WordFilter) Do(c fctx.C) error {
       wf.Out = wf.Blacklist.ReplaceAllString(wf.In, "***")
       return nil
   }
   
   func main() {
       c, cf := fctx.Background()
       defer cf(nil)
   
       c = fctx.WithTag(c, "service", "wordfilter")
   
       srv := fhttp.NewServer(c)
       srv.MustRegisterAPI(c, "/api/wordfilter/v1", &WordFilter{
           Blacklist: regexp.MustCompile(`(foo|bar)`),
       })
   
       addr, err := srv.Listen(c, "127.0.0.1:8080")
       if err != nil {
           panic(err)
       }
       flog.Infof(c, "listening on %s", addr.String())
   
       shutdown.WaitForSignal(c, cf)
   }
   

3. Call the endpoint; the OpenAPI definition is already available at /openapi.json:

   curl -s -X POST localhost:8080/api/wordfilter/v1 \
     -H 'content-type: application/json' \
     -d '{"in":"foo and friends"}'
   

4. Test the same struct without HTTP glue:

   import (
       "regexp"
       "testing"
   
       "github.com/ohait/forego/api"
       "github.com/ohait/forego/test"
    )
   
    func TestWordFilter(t *testing.T) {
        c := test.Context(t)
        out := api.Test(c, &WordFilter{
            Blacklist: regexp.MustCompile(`(foo|bar)`),
            In:        "foo and bar",
        })
   
        test.EqualsStr(t, "*** and ***", out.Out)
    }
   

Architecture Overview

• ctx / ctx/log: wrap context.Context so tags, rich errors, and JSON logs travel together; handlers don’t have to know who consumes the logs.
• http, api, http/ws: map structs to REST and WebSocket endpoints, emit OpenAPI, and reuse the same types in business logic and tests.
• test: AST-aware assertions that reuse your API structs directly, producing readable success and failure output.
• enc: an intermediate JSON representation that keeps parsing efficient when you need custom coercion.
• shutdown, utils/prom, storage: supporting utilities for graceful shutdown, lightweight metrics, and simple storage patterns.

Observability by Default

c = fctx.WithTag(c, "tracking", "a1b2c3")
flog.Infof(c, "completed request")

Produces a JSONL entry similar to:

{"level":"info","message":"completed request","tags":{"service":"wordfilter","tracking":"a1b2c3"}}

Every handler in forego/http automatically enriches tags with user agent, path, remote address, and exposes the same metadata to your own log calls.

Package Tour

• api — bind Go structs to RPC-style operations, generate OpenAPI, and provide helpers to test them directly.
• enc — flexible JSON intermediate forms (enc.Node, enc.Map, enc.Pairs) that avoid json.RawMessage gymnastics.
• http — production-grade HTTP server with automatic request tagging, gzip, OpenAPI serving, and API registration.
• http/ws — WebSocket RPC bindings that reuse the same struct/tag approach as REST.
• ctx — context helpers, tagged metadata, structured logging, and rich error wrappers.
• shutdown — graceful signal handling with hold/release coordination.
• test — expressive assertions powered by source analysis.
• utils/prom — lightweight Prometheus-compatible metrics.
• utils — shared helpers (AST, caches, lists, sync) used across packages.

When to Use / When to Wait

• Use it when you’re building Go JSON or WebSocket services and want consistent logging, automatic documentation, and tests that stay close to your business logic.
• Wait if you need a polished, stable framework or non-Go integrations—this project is still evolving and APIs may move.

Further details live in the package READMEs linked above.