Artifact [91e6d6e3d1]

Artifact 91e6d6e3d19649ba1e9fc2a88046129fb3f073b7a6413bd00dd37e02b39e1274:

• File transport.go — part of check-in [f5744359d3] at 2026-04-19 16:30:54 on branch trunk — Initial open source release

  libfossil is a pure-Go implementation of the Fossil SCM, reading and writing the same .fossil SQLite repository format as upstream Fossil.

  This is the first public release of code that previously lived in a private repository. The module path is github.com/danmestas/libfossil and the binary is named libfossil to avoid $PATH collisions with upstream fossil.

  Included: - Repo lifecycle (create, clone), checkout/checkin, timeline, merge, diff, annotate, shun, tag, branch, bisect, stash, undo/redo - Sync-over-HTTP protocol (client and handler) - Two SQLite drivers: modernc (pure Go, default) and ncruces (wasm-capable) - Observer interfaces (SyncObserver, CheckoutObserver) with an optional OpenTelemetry implementation in observer/otel (separate submodule) - Deterministic simulation testing harness with BUGGIFY fault injection - Kong-based embeddable CLI under cli/ and a standalone binary under cmd/libfossil/ (user: [email protected], size: 2246) [annotate] [blame] [check-ins using]

package libfossil

import (
	"bytes"
	"context"
	"fmt"
	"io"
	"net/http"
)

// Transport delivers sync payloads between peers.
// Implementations handle the network layer (HTTP, NATS, etc.).
// Payloads are opaque zlib-compressed xfer card streams.
type Transport interface {
	RoundTrip(ctx context.Context, payload []byte) ([]byte, error)
}

// NewHTTPTransport creates a Transport that speaks Fossil's HTTP /xfer protocol.
func NewHTTPTransport(url string, opts ...HTTPOption) Transport {
	t := &httpTransport{url: url, client: http.DefaultClient}
	for _, o := range opts {
		o(t)
	}
	return t
}

// HTTPOption configures an HTTP transport.
type HTTPOption func(*httpTransport)

// WithHTTPClient sets a custom http.Client for the transport.
func WithHTTPClient(c *http.Client) HTTPOption {
	return func(t *httpTransport) { t.client = c }
}

type httpTransport struct {
	url    string
	client *http.Client
}

func (t *httpTransport) RoundTrip(ctx context.Context, payload []byte) ([]byte, error) {
	req, err := http.NewRequestWithContext(ctx, "POST", t.url, bytes.NewReader(payload))
	if err != nil {
		return nil, fmt.Errorf("libfossil: http transport: %w", err)
	}
	req.Header.Set("Content-Type", "application/x-fossil")
	resp, err := t.client.Do(req)
	if err != nil {
		return nil, fmt.Errorf("libfossil: http transport: %w", err)
	}
	defer resp.Body.Close()
	body, err := io.ReadAll(resp.Body)
	if err != nil {
		return nil, fmt.Errorf("libfossil: http transport read: %w", err)
	}
	return body, nil
}

// MockTransport is a test double that delegates to a handler function.
type MockTransport struct {
	Handler func(req []byte) []byte
}

// RoundTrip calls the Handler function if set, otherwise returns empty bytes.
func (t *MockTransport) RoundTrip(_ context.Context, payload []byte) ([]byte, error) {
	if t.Handler == nil {
		return []byte{}, nil
	}
	return t.Handler(payload), nil
}

// TransportFunc adapts a plain function to the Transport interface.
// This is the Transport equivalent of http.HandlerFunc.
type TransportFunc func(ctx context.Context, payload []byte) ([]byte, error)

// RoundTrip calls the function.
func (f TransportFunc) RoundTrip(ctx context.Context, payload []byte) ([]byte, error) {
	return f(ctx, payload)
}