feat: initial goget release — modern IPv6-first download utility

internal/protocol/dataurl/dataurl.go

@@ -0,0 +1,105 @@
+//go:build linux || freebsd
+// +build linux freebsd
+
+package dataurl
+
+import (
+	"context"
+	"encoding/base64"
+	"io"
+	"net/url"
+	"os"
+	"strings"
+	"time"
+
+	"codeberg.org/petrbalvin/goget/internal/core"
+	"codeberg.org/petrbalvin/goget/internal/protocol"
+)
+
+// Protocol handles data: URLs (RFC 2397).
+type Protocol struct {
+	*protocol.BaseProtocol
+}
+
+// NewProtocol creates a new data: URL protocol handler.
+func NewProtocol() *Protocol {
+	return &Protocol{
+		BaseProtocol: protocol.NewBaseProtocol(protocol.ProtocolInfo{
+			Name:        "DATA",
+			Scheme:      "data",
+			DefaultPort: 0,
+			Features:    []string{},
+		}),
+	}
+}
+
+func (p *Protocol) Download(ctx context.Context, req *core.DownloadRequest) (*core.DownloadResult, error) {
+	startTime := time.Now()
+
+	// data:[<mediatype>][;base64],<data>
+	data, err := Decode(req.URL.String())
+	if err != nil {
+		return nil, core.NewProtocolError("failed to decode data URL", err, core.SafeURL(req.URL))
+	}
+
+	var writer io.Writer
+	outputPath := req.Output
+
+	if req.Writer != nil {
+		writer = req.Writer
+	} else if outputPath == "" || outputPath == "-" {
+		writer = os.Stdout
+		outputPath = "-"
+	} else {
+		f, err := os.Create(outputPath)
+		if err != nil {
+			return nil, core.NewFileError("failed to create output file", err)
+		}
+		defer f.Close()
+		writer = f
+	}
+
+	n, err := writer.Write(data)
+	if err != nil {
+		return nil, core.NewFileError("failed to write data URL content", err)
+	}
+
+	duration := time.Since(startTime)
+
+	return &core.DownloadResult{
+		BytesDownloaded: int64(n),
+		TotalSize:       int64(len(data)),
+		Duration:        duration,
+		Protocol:        "DATA",
+		IPVersion:       0,
+		Speed:           float64(n) / duration.Seconds(),
+		OutputPath:      outputPath,
+	}, nil
+}
+
+// Decode parses and decodes a data: URL.
+func Decode(rawURL string) ([]byte, error) {
+	if !strings.HasPrefix(rawURL, "data:") {
+		return nil, nil
+	}
+
+	content := strings.TrimPrefix(rawURL, "data:")
+	isBase64 := false
+
+	if idx := strings.Index(content, ";base64,"); idx >= 0 {
+		isBase64 = true
+		content = content[idx+8:]
+	} else if idx := strings.Index(content, ","); idx >= 0 {
+		content = content[idx+1:]
+	}
+
+	decoded, err := url.PathUnescape(content)
+	if err != nil {
+		decoded = content
+	}
+
+	if isBase64 {
+		return base64.StdEncoding.DecodeString(decoded)
+	}
+	return []byte(decoded), nil
+}