New Packet.lua format, test parsing and entire new lua ecossystem

pkg/packet.lua.d/main.go

@@ -0,0 +1,166 @@
+package packet
+
+import (
+	"archive/tar"
+	"errors"
+	"fmt"
+	"io"
+	"path/filepath"
+	"runtime"
+
+	"github.com/klauspost/compress/zstd"
+
+	lua "github.com/yuin/gopher-lua"
+)
+
+type OperationalSystem string
+
+type PacketLua struct {
+	Name        string
+	Version     string
+	Maintaner   string
+	Description string
+	Serial      int
+
+	Plataforms         *map[OperationalSystem]Plataform
+	GlobalSources      *[]Source
+	GlobalDependencies *PkgDependencies
+
+	Build *lua.LFunction
+	Pkg   *lua.LFunction
+}
+
+type Source struct {
+	Method string
+	Url    string
+	Specs  interface{}
+}
+
+type VersionConstraint string
+
+type PkgDependencies struct {
+	RuntimeDependencies *map[string]*VersionConstraint
+	BuildDependencies   *map[string]*VersionConstraint
+	Conflicts           *map[string]*VersionConstraint
+}
+
+type Plataform struct {
+	Name         string
+	Architetures []string
+	Sources      *[]Source
+	Dependencies *PkgDependencies
+}
+
+type GitSpecs struct {
+	Branch string
+	Tag    *string
+}
+
+type POSTSpecs struct {
+	SHA256  *string
+	Body    *string
+	Headers *map[string]string
+}
+
+type GETSpecs struct {
+	SHA256  *string
+	Headers *map[string]string
+}
+
+var ErrCantFindPacketDotLua = errors.New("can't find Packet.lua in .tar.zst file")
+var ErrFileDontReturnTable = errors.New("invalid Packet.lua format: the file do not return a table")
+var ErrCannotFindPackageTable = errors.New("invalid Packet.lua format: can't find package table")
+
+// ReadPacket read a Packet.lua and alredy set global vars
+func ReadPacket(f []byte, cfg *Config) (PacketLua, error) {
+	cfg = checkConfig(cfg)
+
+	L := lua.NewState()
+	defer L.Close()
+
+	osObject := L.GetGlobal("os").(*lua.LTable)
+	ioObject := L.GetGlobal("io").(*lua.LTable)
+
+	L.SetGlobal("os", lua.LNil)
+	L.SetGlobal("io", lua.LNil)
+
+	L.SetGlobal("BIN_DIR", lua.LString(cfg.BinDir))
+	L.SetGlobal("CURRENT_ARCH", lua.LString(runtime.GOARCH))
+	L.SetGlobal("CURRENT_PLATAFORM", lua.LString(runtime.GOOS))
+
+	if err := L.DoString(string(f)); err != nil {
+		return PacketLua{}, err
+	}
+
+	L.SetGlobal("os", osObject)
+	L.SetGlobal("io", ioObject)
+
+	tableLua := L.Get(-1)
+
+	if tableLua.Type() != lua.LTTable {
+		return PacketLua{}, ErrFileDontReturnTable
+	}
+
+	table := tableLua.(*lua.LTable)
+
+	pkgTableLua := table.RawGetString("package")
+	if pkgTableLua.Type() != lua.LTTable {
+		return PacketLua{}, ErrCannotFindPackageTable
+	}
+	pkgTable := pkgTableLua.(*lua.LTable)
+
+	packetLua := &PacketLua{
+		Name:        getStringFromTable(pkgTable, "name"),
+		Version:     getStringFromTable(pkgTable, "version"),
+		Maintaner:   getStringFromTable(pkgTable, "maintainer"),
+		Description: getStringFromTable(pkgTable, "description"),
+		Serial:      getIntFromTable(pkgTable, "serial"),
+
+		Plataforms: getPlataformsFromTable(pkgTable, "plataforms"),
+
+		GlobalDependencies: getDependenciesFromTable(pkgTable, "build_dependencies"),
+		GlobalSources:      getSourcesFromTable(pkgTable, "sources"),
+
+		Build: getFunctionFromTable(table, "build"),
+		Pkg:   getFunctionFromTable(table, "pkg"),
+	}
+
+	if packetLua.Pkg == nil {
+		return PacketLua{}, fmt.Errorf("pkg() does not exist")
+	}
+
+	return *packetLua, nil
+}
+
+func ReadPacketFromZSTDF(file io.Reader, cfg *Config) (PacketLua, error) {
+	cfg = checkConfig(cfg)
+
+	zstdReader, err := zstd.NewReader(file)
+	if err != nil {
+		return PacketLua{}, err
+	}
+	defer zstdReader.Close()
+
+	tarReader := tar.NewReader(zstdReader)
+	for {
+		header, err := tarReader.Next()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			return PacketLua{}, err
+		}
+
+		if filepath.Base(header.Name) == "Packet.lua" {
+
+			packageLuaBlob, err := io.ReadAll(tarReader)
+			if err != nil {
+				return PacketLua{}, err
+			}
+
+			return ReadPacket(packageLuaBlob, cfg)
+		}
+
+	}
+	return PacketLua{}, ErrCantFindPacketDotLua
+}