refactor: switch gateway code to new API from go-libipfs (#9681)

Co-authored-by: Marcin Rataj <lidel@lidel.org>
Co-authored-by: Henrique Dias <hacdias@gmail.com>

core/corehttp/gateway.go

@@ -2,24 +2,26 @@ package corehttp
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"io"
 	"net"
 	"net/http"
 
+	"github.com/ipfs/boxo/blockservice"
 	iface "github.com/ipfs/boxo/coreiface"
-	options "github.com/ipfs/boxo/coreiface/options"
-	nsopts "github.com/ipfs/boxo/coreiface/options/namesys"
 	"github.com/ipfs/boxo/coreiface/path"
+	"github.com/ipfs/boxo/exchange/offline"
 	"github.com/ipfs/boxo/files"
 	"github.com/ipfs/boxo/gateway"
 	"github.com/ipfs/boxo/namesys"
-	"github.com/ipfs/go-block-format"
+	offlineroute "github.com/ipfs/boxo/routing/offline"
 	cid "github.com/ipfs/go-cid"
 	version "github.com/ipfs/kubo"
 	config "github.com/ipfs/kubo/config"
 	core "github.com/ipfs/kubo/core"
-	coreapi "github.com/ipfs/kubo/core/coreapi"
+	"github.com/ipfs/kubo/core/node"
+	"github.com/libp2p/go-libp2p/core/routing"
 	id "github.com/libp2p/go-libp2p/p2p/protocol/identify"
 	"go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp"
 )
@@ -42,7 +44,7 @@ func GatewayOption(paths ...string) ServeOption {
 			Headers: headers,
 		}
 
-		gwAPI, err := newGatewayAPI(n)
+		gwAPI, err := newGatewayBackend(n)
 		if err != nil {
 			return nil, err
 		}
@@ -70,7 +72,7 @@ func HostnameOption() ServeOption {
 			return nil, err
 		}
 
-		gwAPI, err := newGatewayAPI(n)
+		gwAPI, err := newGatewayBackend(n)
 		if err != nil {
 			return nil, err
 		}
@@ -93,83 +95,120 @@ func VersionOption() ServeOption {
 	}
 }
 
-type gatewayAPI struct {
-	ns         namesys.NameSystem
-	api        iface.CoreAPI
-	offlineAPI iface.CoreAPI
-}
-
-func newGatewayAPI(n *core.IpfsNode) (*gatewayAPI, error) {
+func newGatewayBackend(n *core.IpfsNode) (gateway.IPFSBackend, error) {
 	cfg, err := n.Repo.Config()
 	if err != nil {
 		return nil, err
 	}
 
-	api, err := coreapi.NewCoreAPI(n, options.Api.FetchBlocks(!cfg.Gateway.NoFetch))
+	bserv := n.Blocks
+	var vsRouting routing.ValueStore = n.Routing
+	nsys := n.Namesys
+	if cfg.Gateway.NoFetch {
+		bserv = blockservice.New(bserv.Blockstore(), offline.Exchange(bserv.Blockstore()))
+
+		cs := cfg.Ipns.ResolveCacheSize
+		if cs == 0 {
+			cs = node.DefaultIpnsCacheSize
+		}
+		if cs < 0 {
+			return nil, fmt.Errorf("cannot specify negative resolve cache size")
+		}
+
+		vsRouting = offlineroute.NewOfflineRouter(n.Repo.Datastore(), n.RecordValidator)
+		nsys, err = namesys.NewNameSystem(vsRouting,
+			namesys.WithDatastore(n.Repo.Datastore()),
+			namesys.WithDNSResolver(n.DNSResolver),
+			namesys.WithCache(cs))
+		if err != nil {
+			return nil, fmt.Errorf("error constructing namesys: %w", err)
+		}
+	}
+
+	gw, err := gateway.NewBlocksGateway(bserv, gateway.WithValueStore(vsRouting), gateway.WithNameSystem(nsys))
 	if err != nil {
 		return nil, err
 	}
-	offlineAPI, err := api.WithOptions(options.Api.Offline(true))
-	if err != nil {
-		return nil, err
+	return &offlineGatewayErrWrapper{gwimpl: gw}, nil
+}
+
+type offlineGatewayErrWrapper struct {
+	gwimpl gateway.IPFSBackend
+}
+
+func offlineErrWrap(err error) error {
+	if errors.Is(err, iface.ErrOffline) {
+		return fmt.Errorf("%s : %w", err.Error(), gateway.ErrServiceUnavailable)
 	}
-
-	return &gatewayAPI{
-		ns:         n.Namesys,
-		api:        api,
-		offlineAPI: offlineAPI,
-	}, nil
+	return err
 }
 
-func (gw *gatewayAPI) GetUnixFsNode(ctx context.Context, pth path.Resolved) (files.Node, error) {
-	return gw.api.Unixfs().Get(ctx, pth)
+func (o *offlineGatewayErrWrapper) Get(ctx context.Context, path gateway.ImmutablePath) (gateway.ContentPathMetadata, *gateway.GetResponse, error) {
+	md, n, err := o.gwimpl.Get(ctx, path)
+	err = offlineErrWrap(err)
+	return md, n, err
 }
 
-func (gw *gatewayAPI) LsUnixFsDir(ctx context.Context, pth path.Resolved) (<-chan iface.DirEntry, error) {
-	// Optimization: use Unixfs.Ls without resolving children, but using the
-	// cumulative DAG size as the file size. This allows for a fast listing
-	// while keeping a good enough Size field.
-	return gw.api.Unixfs().Ls(ctx, pth,
-		options.Unixfs.ResolveChildren(false),
-		options.Unixfs.UseCumulativeSize(true),
-	)
+func (o *offlineGatewayErrWrapper) GetRange(ctx context.Context, path gateway.ImmutablePath, ranges ...gateway.GetRange) (gateway.ContentPathMetadata, files.File, error) {
+	md, n, err := o.gwimpl.GetRange(ctx, path, ranges...)
+	err = offlineErrWrap(err)
+	return md, n, err
 }
 
-func (gw *gatewayAPI) GetBlock(ctx context.Context, cid cid.Cid) (blocks.Block, error) {
-	r, err := gw.api.Block().Get(ctx, path.IpfsPath(cid))
-	if err != nil {
-		return nil, err
-	}
-
-	data, err := io.ReadAll(r)
-	if err != nil {
-		return nil, err
-	}
-
-	return blocks.NewBlockWithCid(data, cid)
+func (o *offlineGatewayErrWrapper) GetAll(ctx context.Context, path gateway.ImmutablePath) (gateway.ContentPathMetadata, files.Node, error) {
+	md, n, err := o.gwimpl.GetAll(ctx, path)
+	err = offlineErrWrap(err)
+	return md, n, err
 }
 
-func (gw *gatewayAPI) GetIPNSRecord(ctx context.Context, c cid.Cid) ([]byte, error) {
-	return gw.api.Routing().Get(ctx, "/ipns/"+c.String())
+func (o *offlineGatewayErrWrapper) GetBlock(ctx context.Context, path gateway.ImmutablePath) (gateway.ContentPathMetadata, files.File, error) {
+	md, n, err := o.gwimpl.GetBlock(ctx, path)
+	err = offlineErrWrap(err)
+	return md, n, err
 }
 
-func (gw *gatewayAPI) GetDNSLinkRecord(ctx context.Context, hostname string) (path.Path, error) {
-	p, err := gw.ns.Resolve(ctx, "/ipns/"+hostname, nsopts.Depth(1))
-	if err == namesys.ErrResolveRecursion {
-		err = nil
-	}
-	return path.New(p.String()), err
+func (o *offlineGatewayErrWrapper) Head(ctx context.Context, path gateway.ImmutablePath) (gateway.ContentPathMetadata, files.Node, error) {
+	md, n, err := o.gwimpl.Head(ctx, path)
+	err = offlineErrWrap(err)
+	return md, n, err
 }
 
-func (gw *gatewayAPI) IsCached(ctx context.Context, pth path.Path) bool {
-	_, err := gw.offlineAPI.Block().Stat(ctx, pth)
-	return err == nil
+func (o *offlineGatewayErrWrapper) ResolvePath(ctx context.Context, path gateway.ImmutablePath) (gateway.ContentPathMetadata, error) {
+	md, err := o.gwimpl.ResolvePath(ctx, path)
+	err = offlineErrWrap(err)
+	return md, err
 }
 
-func (gw *gatewayAPI) ResolvePath(ctx context.Context, pth path.Path) (path.Resolved, error) {
-	return gw.api.ResolvePath(ctx, pth)
+func (o *offlineGatewayErrWrapper) GetCAR(ctx context.Context, path gateway.ImmutablePath) (gateway.ContentPathMetadata, io.ReadCloser, <-chan error, error) {
+	md, data, errCh, err := o.gwimpl.GetCAR(ctx, path)
+	err = offlineErrWrap(err)
+	return md, data, errCh, err
 }
 
+func (o *offlineGatewayErrWrapper) IsCached(ctx context.Context, path path.Path) bool {
+	return o.gwimpl.IsCached(ctx, path)
+}
+
+func (o *offlineGatewayErrWrapper) GetIPNSRecord(ctx context.Context, c cid.Cid) ([]byte, error) {
+	rec, err := o.gwimpl.GetIPNSRecord(ctx, c)
+	err = offlineErrWrap(err)
+	return rec, err
+}
+
+func (o *offlineGatewayErrWrapper) ResolveMutable(ctx context.Context, path path.Path) (gateway.ImmutablePath, error) {
+	imPath, err := o.gwimpl.ResolveMutable(ctx, path)
+	err = offlineErrWrap(err)
+	return imPath, err
+}
+
+func (o *offlineGatewayErrWrapper) GetDNSLinkRecord(ctx context.Context, s string) (path.Path, error) {
+	p, err := o.gwimpl.GetDNSLinkRecord(ctx, s)
+	err = offlineErrWrap(err)
+	return p, err
+}
+
+var _ gateway.IPFSBackend = (*offlineGatewayErrWrapper)(nil)
+
 var defaultPaths = []string{"/ipfs/", "/ipns/", "/api/", "/p2p/"}
 
 var subdomainGatewaySpec = &gateway.Specification{