appview/sites: add deploy, delete, and kv domain mapping logic

Signed-off-by: Anirudh Oppiliappan <[e-mail]>

appview/sites/sites.go

···
+package sites
+
+import (
+	"archive/tar"
+	"bytes"
+	"compress/gzip"
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"io/fs"
+	"os"
+	"path/filepath"
+	"strings"
+
+	indigoxrpc "github.com/bluesky-social/indigo/xrpc"
+	"tangled.org/core/api/tangled"
+	"tangled.org/core/appview/cloudflare"
+)
+
+// DomainMapping is the value stored in Workers KV, keyed by the bare domain.
+// Repos maps repo name → is_index; at most one repo may have is_index = true.
+type DomainMapping struct {
+	Did   string          `json:"did"`
+	Repos map[string]bool `json:"repos"`
+}
+
+// getOrNewMapping fetches the existing KV entry for domain, or returns a
+// fresh empty mapping for the given did if none exists yet.
+func getOrNewMapping(ctx context.Context, cf *cloudflare.Client, domain, did string) (DomainMapping, error) {
+	raw, err := cf.KVGet(ctx, domain)
+	if err != nil {
+		return DomainMapping{}, fmt.Errorf("reading domain mapping for %q: %w", domain, err)
+	}
+	if raw == nil {
+		return DomainMapping{Did: did, Repos: make(map[string]bool)}, nil
+	}
+	var m DomainMapping
+	if err := json.Unmarshal(raw, &m); err != nil {
+		return DomainMapping{}, fmt.Errorf("unmarshalling domain mapping for %q: %w", domain, err)
+	}
+	if m.Repos == nil {
+		m.Repos = make(map[string]bool)
+	}
+	return m, nil
+}
+
+// PutDomainMapping adds or updates a single repo entry within the per-domain
+// KV record. If isIndex is true, any previously indexed repo is demoted first.
+func PutDomainMapping(ctx context.Context, cf *cloudflare.Client, domain, did, repo string, isIndex bool) error {
+	m, err := getOrNewMapping(ctx, cf, domain, did)
+	if err != nil {
+		return err
+	}
+
+	m.Did = did
+	m.Repos[repo] = isIndex
+
+	val, err := json.Marshal(m)
+	if err != nil {
+		return fmt.Errorf("marshalling domain mapping: %w", err)
+	}
+	if err := cf.KVPut(ctx, domain, val); err != nil {
+		return fmt.Errorf("putting domain mapping for %q: %w", domain, err)
+	}
+	return nil
+}
+
+// DeleteDomainMapping removes a single repo from the per-domain KV record.
+// If it was the last repo, the key is deleted entirely.
+func DeleteDomainMapping(ctx context.Context, cf *cloudflare.Client, domain, repo string) error {
+	m, err := getOrNewMapping(ctx, cf, domain, "")
+	if err != nil {
+		return err
+	}
+
+	delete(m.Repos, repo)
+
+	if len(m.Repos) == 0 {
+		if err := cf.KVDelete(ctx, domain); err != nil {
+			return fmt.Errorf("deleting domain mapping for %q: %w", domain, err)
+		}
+		return nil
+	}
+
+	val, err := json.Marshal(m)
+	if err != nil {
+		return fmt.Errorf("marshalling domain mapping: %w", err)
+	}
+	if err := cf.KVPut(ctx, domain, val); err != nil {
+		return fmt.Errorf("putting domain mapping for %q: %w", domain, err)
+	}
+	return nil
+}
+
+// DeleteAllDomainMappings removes the KV entry for a domain entirely.
+// Used when a user releases their domain claim.
+func DeleteAllDomainMappings(ctx context.Context, cf *cloudflare.Client, domain string) error {
+	if err := cf.KVDelete(ctx, domain); err != nil {
+		return fmt.Errorf("deleting all domain mappings for %q: %w", domain, err)
+	}
+	return nil
+}
+
+// prefix returns the R2 key prefix for a given repo: "{did}/{repo}/".
+// All site objects live under this prefix.
+func prefix(repoDid, repoName string) string {
+	return repoDid + "/" + repoName + "/"
+}
+
+// Deploy fetches the repo archive at the given branch from knotHost, extracts
+// deployDir from it, and syncs the resulting files to R2 via cf.SyncFiles.
+// It is the authoritative entry-point for deploying a git site.
+func Deploy(
+	ctx context.Context,
+	cf *cloudflare.Client,
+	knotHost, repoDid, repoName, branch, deployDir string,
+) error {
+	tmpDir, err := os.MkdirTemp("", "tangled-sites-*")
+	if err != nil {
+		return fmt.Errorf("creating temp dir: %w", err)
+	}
+	defer os.RemoveAll(tmpDir)
+
+	if err := extractArchive(ctx, knotHost, repoDid, repoName, branch, tmpDir); err != nil {
+		return fmt.Errorf("extracting archive: %w", err)
+	}
+
+	// deployDir is absolute within the repo (e.g. "/" or "/docs").
+	// Map it to a path inside tmpDir.
+	deployRoot := filepath.Join(tmpDir, filepath.FromSlash(deployDir))
+
+	files := make(map[string][]byte)
+	err = filepath.WalkDir(deployRoot, func(p string, d fs.DirEntry, err error) error {
+		if err != nil {
+			return err
+		}
+		if d.IsDir() {
+			return nil
+		}
+		content, err := os.ReadFile(p)
+		if err != nil {
+			return err
+		}
+		rel, err := filepath.Rel(deployRoot, p)
+		if err != nil {
+			return err
+		}
+		files[filepath.ToSlash(rel)] = content
+		return nil
+	})
+	if err != nil {
+		return fmt.Errorf("walking deploy dir: %w", err)
+	}
+
+	if err := cf.SyncFiles(ctx, prefix(repoDid, repoName), files); err != nil {
+		return fmt.Errorf("syncing files to R2: %w", err)
+	}
+
+	return nil
+}
+
+// Delete removes all R2 objects for a repo site.
+func Delete(ctx context.Context, cf *cloudflare.Client, repoDid, repoName string) error {
+	if err := cf.DeleteFiles(ctx, prefix(repoDid, repoName)); err != nil {
+		return fmt.Errorf("deleting site files from R2: %w", err)
+	}
+	return nil
+}
+
+// extractArchive fetches the tar.gz archive for the given repo+branch from
+// the knot via XRPC and extracts it into destDir.
+func extractArchive(ctx context.Context, knotHost, repoDid, repoName, branch, destDir string) error {
+	xrpcc := &indigoxrpc.Client{Host: knotHost}
+	data, err := tangled.RepoArchive(ctx, xrpcc, "tar.gz", "", branch, repoDid+"/"+repoName)
+	if err != nil {
+		return fmt.Errorf("fetching archive: %w", err)
+	}
+
+	gz, err := gzip.NewReader(bytes.NewReader(data))
+	if err != nil {
+		return fmt.Errorf("opening gzip stream: %w", err)
+	}
+	defer gz.Close()
+
+	tr := tar.NewReader(gz)
+	for {
+		hdr, err := tr.Next()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			return fmt.Errorf("reading tar: %w", err)
+		}
+
+		// The knot always adds a leading prefix dir (e.g. "myrepo-main/"); strip it.
+		name := hdr.Name
+		i := strings.Index(name, "/")
+		if i < 0 {
+			continue
+		}
+		name = name[i+1:]
+		if name == "" {
+			continue
+		}
+
+		target := filepath.Join(destDir, filepath.FromSlash(name))
+
+		// Guard against zip-slip.
+		if !strings.HasPrefix(target, filepath.Clean(destDir)+string(os.PathSeparator)) {
+			continue
+		}
+
+		switch hdr.Typeflag {
+		case tar.TypeDir:
+			if err := os.MkdirAll(target, 0o755); err != nil {
+				return err
+			}
+		case tar.TypeReg:
+			if err := os.MkdirAll(filepath.Dir(target), 0o755); err != nil {
+				return err
+			}
+			f, err := os.OpenFile(target, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, hdr.FileInfo().Mode())
+			if err != nil {
+				return err
+			}
+			if _, err := io.Copy(f, tr); err != nil {
+				f.Close()
+				return err
+			}
+			f.Close()
+		}
+	}
+
+	return nil
+}