wasi-module-sdk-go/context.go

package sdk

import (
	"context"
	"crypto/md5"
	"golang.org/x/exp/slog"
	"io"
	"os"
)

var _ ExecutionContext = (*wasiExecutionContext)(nil)

func newWasiExecutionContext(
	ctx context.Context,
	logger *slog.Logger,
	modName string,
	mod Module,
	repoRoot, binDir, outDir string,
) *wasiExecutionContext {
	return &wasiExecutionContext{
		Context:  ctx,
		logger:   logger,
		modName:  modName,
		mod:      mod,
		repoRoot: repoRoot,
		outDir:   outDir,
		binDir:   binDir,
	}
}

type wasiExecutionContext struct {
	context.Context
	stateProxy StateProxy
	logger     *slog.Logger
	mod        Module
	modName    string
	repoRoot   string
	outDir     string
	binDir     string
}

func (w wasiExecutionContext) WorkingDir() string {
	return w.repoRoot
}

func (w wasiExecutionContext) OutDir() string {
	return w.outDir
}

func (w wasiExecutionContext) BinariesDir() string {
	return w.binDir
}

func (w wasiExecutionContext) StdOut() io.Writer {
	return os.Stdout
}

func (w wasiExecutionContext) StdErr() io.Writer {
	return os.Stderr
}

func (w wasiExecutionContext) Logger() *slog.Logger {
	return w.logger
}

func (w wasiExecutionContext) GetState(_ context.Context, key string) ([]byte, StateMetadata, error) {
	return w.stateProxy.Get(w.keyBytes(w.mod.Category().String(), w.modName, key))
}

func (w wasiExecutionContext) SetState(_ context.Context, key string, value []byte) error {
	return w.stateProxy.Set(w.keyBytes(w.mod.Category().String(), w.modName, key), value)
}

func (w wasiExecutionContext) keyBytes(parts ...string) []byte {
	if len(parts) == 0 {
		return nil
	}

	h := md5.New()
	for i := range parts {
		_, _ = h.Write([]byte(parts[i]))
	}

	return h.Sum(nil)
}