JuliusBrussee/caveman · error

cacheengine: nil engine

Error message

cacheengine: nil engine

What it means

Optimize was invoked on a nil or incompletely constructed Engine (nil receiver, or missing guard/prefix-safety/profile-resolver internals). Engines built by New are always complete; this guard catches zero-value or manually assembled structs.

Source

Thrown at cacheengine/native.go:20

import (
	"bytes"
	"context"
	"encoding/json"
	"errors"
	"io"
	"strconv"
	"strings"
	"time"

	"github.com/JuliusBrussee/caveman/proxy/providers/jsonsplice"
)

// Optimize applies provider-native cache metadata or returns copied original
// bytes on every unsupported or unsafe path. It makes no network call.
func (e *Engine) Optimize(ctx context.Context, request NativeRequest) (NativeResult, error) {
	if e == nil || e.guard == nil || e.prefixSafety == nil || e.resolveProfile == nil {
		return NativeResult{}, errors.New("cacheengine: nil engine")
	}
	if e.configErr != nil {
		return NativeResult{}, e.configErr
	}
	if ctx == nil {
		return NativeResult{}, errors.New("cacheengine: nil context")
	}
	if err := ctx.Err(); err != nil {
		return NativeResult{}, err
	}
	if len(request.Body) > e.maxRequestBytes {
		return NativeResult{}, errors.New("cacheengine: request exceeds configured byte limit")
	}
	original := append([]byte(nil), request.Body...)
	unsupported := Profile{ID: "unsupported", Mode: ModeUnsupported, Attribution: AttributionNone}
	result := NativeResult{
		Body:     original,
		Decision: DecisionPassThrough,

View on GitHub (pinned to 766dce6b13)

Solutions

1. Construct the engine via cacheengine.New/NewChecked before calling Optimize
2. Check the engine pointer at call sites that may receive an optional engine

When it happens

Trigger: Thrown at cacheengine/native.go:20 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of JuliusBrussee/caveman@766dce6b13 (2026-08-18). Data as JSON: /api/errors/e11f83fe69362c04. Report an issue: GitHub.