From 208424de988e8ca9b7a4ac9f00403ba3e5a41ca8 Mon Sep 17 00:00:00 2001
From: Peter Kurfer <peter.kurfer@gmail.com>
Date: Fri, 5 May 2023 10:11:12 +0200
Subject: [PATCH] initial commit

---
 examples/hello_world/go.mod | 11 +++++++
 go.mod                      |  8 +++++
 go.sum                      |  9 ++++++
 test/test_host.go           | 62 +++++++++++++++++++++++++++++++++++++
 4 files changed, 90 insertions(+)
 create mode 100644 examples/hello_world/go.mod
 create mode 100644 go.mod
 create mode 100644 go.sum
 create mode 100644 test/test_host.go

diff --git a/examples/hello_world/go.mod b/examples/hello_world/go.mod
new file mode 100644
index 0000000..a059774
--- /dev/null
+++ b/examples/hello_world/go.mod
@@ -0,0 +1,11 @@
+module hello_world
+
+go 1.20
+
+require (
+code.icb4dc0.de/buildr/wasi-module-sdk latest
+)
+
+replace (
+	code.icb4dc0.de/buildr/wasi-module-sdk => ../../
+)
\ No newline at end of file
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..7ba3f28
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,8 @@
+module code.icb4dc0.de/buildr/wasi-module-sdk
+
+go 1.20
+
+require (
+	buf.build/gen/go/buildr/buildr/protocolbuffers/go v1.30.0-20230504155321-a2ad89049f80.1 // indirect
+	github.com/tetratelabs/wazero v1.1.0 // indirect
+)
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..94155d4
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,9 @@
+buf.build/gen/go/buildr/buildr/protocolbuffers/go v1.30.0-20230504155321-a2ad89049f80.1 h1:gDR2MbPrmDLMU4SU83sLG53G1BO2jWLZRSwA7Zx/ORs=
+buf.build/gen/go/buildr/buildr/protocolbuffers/go v1.30.0-20230504155321-a2ad89049f80.1/go.mod h1:HnJwr6AoSkS1h+Fr8+UR7MDcZMzmv7lJPJWeTjdclPs=
+github.com/golang/protobuf v1.5.0/go.mod h1:FsONVRAS9T7sI+LIUmWTfcYkHO4aIWwzhcaSAoJOfIk=
+github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
+github.com/tetratelabs/wazero v1.1.0 h1:EByoAhC+QcYpwSZJSs/aV0uokxPwBgKxfiokSUwAknQ=
+github.com/tetratelabs/wazero v1.1.0/go.mod h1:wYx2gNRg8/WihJfSDxA1TIL8H+GkfLYm+bIfbblu9VQ=
+golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+google.golang.org/protobuf v1.26.0-rc.1/go.mod h1:jlhhOSvTdKEhbULTjvd4ARK9grFBp09yW+WbY/TyQbw=
+google.golang.org/protobuf v1.30.0/go.mod h1:HV8QOd/L58Z+nl8r43ehVNZIU/HEI6OcFqwMG9pJV4I=
diff --git a/test/test_host.go b/test/test_host.go
new file mode 100644
index 0000000..08a67fe
--- /dev/null
+++ b/test/test_host.go
@@ -0,0 +1,62 @@
+package test
+
+import (
+	rpcv1 "buf.build/gen/go/buildr/buildr/protocolbuffers/go/rpc/v1"
+	"context"
+	"errors"
+	"github.com/tetratelabs/wazero"
+	"github.com/tetratelabs/wazero/api"
+	"github.com/tetratelabs/wazero/imports/wasi_snapshot_preview1"
+	"golang.org/x/exp/slog"
+	"google.golang.org/protobuf/proto"
+)
+
+type Host struct {
+	Logger *slog.Logger
+}
+
+func (h *Host) Run(ctx context.Context) (err error) {
+	r := wazero.NewRuntime(ctx)
+	defer r.Close(context.Background())
+
+	_, err = r.NewHostModuleBuilder("test").
+		NewFunctionBuilder().WithFunc(h.log).Export("log").
+		Instantiate(ctx)
+
+	if err != nil {
+		return err
+	}
+
+	closer, err := wasi_snapshot_preview1.Instantiate(ctx, r)
+	if err != nil {
+		return err
+	}
+
+	defer func() {
+		err = errors.Join(err, closer.Close(context.Background()))
+	}()
+
+	return nil
+}
+
+func (h *Host) log(ctx context.Context, m api.Module, offset, byteCount uint32) {
+	buf, ok := m.Memory().Read(offset, byteCount)
+	if !ok {
+		return
+	}
+
+	var taskLog *rpcv1.TaskLog
+	if err := proto.Unmarshal(buf, taskLog); err != nil {
+		h.Logger.Warn("failed to unmarshal task log", slog.String("err", err.Error()))
+		return
+	}
+
+	rec := slog.NewRecord(taskLog.Time.AsTime(), slog.Level(taskLog.Level), taskLog.Message, -1)
+
+	for i := range taskLog.Attributes {
+		attr := taskLog.Attributes[i]
+		rec.AddAttrs(slog.String(attr.Key, attr.Value))
+	}
+
+	_ = h.Logger.Handler().Handle(ctx, rec)
+}