Merge pull request ethereum#212 from ethersphere/swarm-mutableresourc…

…es-errors

Add granular error reporting in mutable resources

swarm/api/api.go

@@ -36,6 +36,18 @@ import (
 
 var hashMatcher = regexp.MustCompile("^[0-9A-Fa-f]{64}")
 
+type ErrResourceReturn struct {
+	key string
+}
+
+func (e *ErrResourceReturn) Error() string {
+	return "resourceupdate"
+}
+
+func (e *ErrResourceReturn) Key() string {
+	return e.key
+}
+
 type Resolver interface {
 	Resolve(string) (common.Hash, error)
 }
@@ -145,6 +157,18 @@ func (self *Api) Get(key storage.Key, path string) (reader storage.LazySectionRe
 	entry, _ := trie.getEntry(path)
 
 	if entry != nil {
+		// we want to be able to serve Mutable Resource Updates transparently using the bzz:// scheme
+		//
+		// we use a special manifest hack for this purpose, which is pathless and where the resource root key
+		// is set as the hash of the manifest (see swarm/api/manifest.go:NewResourceManifest)
+		//
+		// to avoid taking a performance hit hacking a storage.LazySectionReader to wrap the resource key,
+		// we return a typed error instead. Since for all other purposes this is an invalid manifest,
+		// any normal interfacing code will just see an error fail accordingly.
+		if entry.ContentType == ResourceContentType {
+			log.Warn("resource type", "hash", entry.Hash)
+			return nil, entry.ContentType, http.StatusOK, &ErrResourceReturn{entry.Hash}
+		}
 		key = common.Hex2Bytes(entry.Hash)
 		status = entry.Status
 		if status == http.StatusMultipleChoices {
@@ -370,11 +394,7 @@ func (self *Api) ResourceLookup(ctx context.Context, name string, period uint32,
 	var err error
 	if version != 0 {
 		if period == 0 {
-			currentblocknumber, err := self.resource.GetBlock(ctx)
-			if err != nil {
-				return nil, nil, fmt.Errorf("Could not determine latest block: %v", err)
-			}
-			period = self.resource.BlockToPeriod(name, currentblocknumber)
+			return nil, nil, storage.NewResourceError(storage.ErrInvalidValue, "Period can't be 0")
 		}
 		_, err = self.resource.LookupVersionByName(ctx, name, period, version, true)
 	} else if period != 0 {

swarm/api/http/server.go

@@ -43,6 +43,12 @@ import (
 	"github.com/rs/cors"
 )
 
+type resourceResponse struct {
+	Manifest storage.Key `json:"manifest"`
+	Resource string      `json:"resource"`
+	Update   storage.Key `json:"update"`
+}
+
 // ServerConfig is the basic configuration needed for the HTTP server and also
 // includes CORS settings.
 type ServerConfig struct {
@@ -292,7 +298,7 @@ func (s *Server) HandleDelete(w http.ResponseWriter, r *Request) {
 }
 
 func (s *Server) HandlePostResource(w http.ResponseWriter, r *Request) {
-	var outdata string
+	var outdata []byte
 	if r.uri.Path != "" {
 		frequency, err := strconv.ParseUint(r.uri.Path, 10, 64)
 		if err != nil {
@@ -301,10 +307,26 @@ func (s *Server) HandlePostResource(w http.ResponseWriter, r *Request) {
 		}
 		key, err := s.api.ResourceCreate(r.Context(), r.uri.Addr, frequency)
 		if err != nil {
-			ShowError(w, &r.Request, fmt.Sprintf("Error serving %s %s: %s", r.Method, r.uri, fmt.Errorf("Resource creation failed: %v", err)), http.StatusInternalServerError)
+			code, err2 := s.translateResourceError(w, r, "Resource creation fail", err)
+
+			ShowError(w, &r.Request, fmt.Sprintf("Error serving %s %s: %s", r.Method, r.uri, err2), code)
+			return
+		}
+		m, err := s.api.NewResourceManifest(r.uri.Addr)
+		if err != nil {
+			ShowError(w, &r.Request, fmt.Sprintf("Error serving %s %s: %s", r.Method, r.uri, fmt.Errorf("Failed to create resource manifest: %v", err)), http.StatusInternalServerError)
+			return
+		}
+		rsrcResponse := &resourceResponse{
+			Manifest: m,
+			Resource: r.uri.Addr,
+			Update:   key,
+		}
+		outdata, err = json.Marshal(rsrcResponse)
+		if err != nil {
+			ShowError(w, &r.Request, fmt.Sprintf("Error serving %s %s: %s", r.Method, r.uri, fmt.Errorf("Failed to create json response for %v: error was: %v", r, err)), http.StatusInternalServerError)
 			return
 		}
-		outdata = key.Hex()
 	}
 
 	data, err := ioutil.ReadAll(r.Body)
@@ -314,14 +336,16 @@ func (s *Server) HandlePostResource(w http.ResponseWriter, r *Request) {
 	}
 	_, _, _, err = s.api.ResourceUpdate(r.Context(), r.uri.Addr, data)
 	if err != nil {
-		ShowError(w, &r.Request, fmt.Sprintf("Error serving %s %s: %s", r.Method, r.uri, fmt.Errorf("Update resource failed: %v", err)), http.StatusInternalServerError)
+		code, err2 := s.translateResourceError(w, r, "Mutable resource update fail", err)
+
+		ShowError(w, &r.Request, fmt.Sprintf("Error serving %s %s: %s", r.Method, r.uri, err2), code)
 		return
 	}
 
-	if outdata != "" {
+	if len(outdata) > 0 {
 		w.Header().Add("Content-type", "text/plain")
 		w.WriteHeader(http.StatusOK)
-		fmt.Fprint(w, outdata)
+		fmt.Fprint(w, string(outdata))
 		return
 	}
 	w.WriteHeader(http.StatusOK)
@@ -372,14 +396,43 @@ func (s *Server) handleGetResource(w http.ResponseWriter, r *Request, name strin
 		return
 	}
 	if err != nil {
-		ShowError(w, &r.Request, fmt.Sprintf("Error serving %s %s: %s", r.Method, r.uri, fmt.Errorf("Mutable resource lookup failed: %v", err)), http.StatusInternalServerError)
+		code, err2 := s.translateResourceError(w, r, "Mutable resource lookup fail", err)
+
+		ShowError(w, &r.Request, fmt.Sprintf("Error serving %s %s: %s", r.Method, r.uri, err2), code)
 		return
 	}
 	log.Debug("Found update", "key", updateKey)
 	w.Header().Set("Content-Type", "application/octet-stream")
 	http.ServeContent(w, &r.Request, "", now, bytes.NewReader(data))
 }
 
+func (s *Server) translateResourceError(w http.ResponseWriter, r *Request, supErr string, err error) (int, error) {
+	code := 0
+	defaultErr := fmt.Errorf("%s: %v", supErr, err)
+	rsrcErr, ok := err.(*storage.ResourceError)
+	if !ok {
+		code = rsrcErr.Code()
+	}
+	switch code {
+	case storage.ErrInvalidValue:
+		//s.BadRequest(w, r, defaultErr.Error())
+		return http.StatusBadRequest, defaultErr
+	case storage.ErrNotFound, storage.ErrNotSynced, storage.ErrNothingToReturn:
+		//s.NotFound(w, r, defaultErr)
+		return http.StatusNotFound, defaultErr
+	case storage.ErrUnauthorized, storage.ErrInvalidSignature:
+		//ShowError(w, &r.Request, defaultErr.Error(), http.StatusUnauthorized)
+		return http.StatusUnauthorized, defaultErr
+	case storage.ErrDataOverflow:
+		//ShowError(w, &r.Request, defaultErr.Error(), http.StatusRequestEntityTooLarge)
+		return http.StatusRequestEntityTooLarge, defaultErr
+	}
+
+	return http.StatusInternalServerError, defaultErr
+
+	//s.Error(w, r, defaultErr)
+}
+
 // HandleGet handles a GET request to
 // - bzz-raw://<key> and responds with the raw content stored at the
 //   given storage key
@@ -640,7 +693,14 @@ func (s *Server) HandleGetFile(w http.ResponseWriter, r *Request) {
 	}
 
 	reader, contentType, status, err := s.api.Get(key, r.uri.Path)
+
 	if err != nil {
+		// cheeky, cheeky hack. See swarm/api/api.go:Api.Get() for an explanation
+		if rsrcErr, ok := err.(*api.ErrResourceReturn); ok {
+			log.Trace("getting resource proxy", "err", rsrcErr.Key())
+			s.handleGetResource(w, r, rsrcErr.Key())
+			return
+		}
 		switch status {
 		case http.StatusNotFound:
 			ShowError(w, &r.Request, fmt.Sprintf("NOT FOUND error serving %s %s: %s", r.Method, r.uri, err), http.StatusNotFound)

swarm/api/http/server_test.go

@@ -19,27 +19,44 @@ package http_test
 import (
 	"bytes"
 	"crypto/rand"
+	"encoding/json"
 	"errors"
+	"flag"
 	"fmt"
 	"io/ioutil"
 	"net/http"
+	"os"
 	"strings"
 	"testing"
 
 	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/swarm/api"
 	swarm "github.com/ethereum/go-ethereum/swarm/api/client"
 	"github.com/ethereum/go-ethereum/swarm/storage"
 	"github.com/ethereum/go-ethereum/swarm/testutil"
 )
 
+func init() {
+	verbose := flag.Bool("v", false, "verbose")
+	flag.Parse()
+	if *verbose {
+		log.Root().SetHandler(log.CallerFileHandler(log.LvlFilterHandler(log.LvlTrace, log.StreamHandler(os.Stderr, log.TerminalFormat(true)))))
+	}
+}
+
+type resourceResponse struct {
+	Manifest storage.Key `json:"manifest"`
+	Resource string      `json:"resource"`
+	Update   storage.Key `json:"update"`
+}
+
 func TestBzzResource(t *testing.T) {
 	srv := testutil.NewTestSwarmServer(t)
 	defer srv.Close()
 
 	// our mutable resource "name"
-	keybytes := make([]byte, common.HashLength)
-	copy(keybytes, []byte{42})
+	keybytes := []byte("foo")
 	srv.Hasher.Reset()
 	srv.Hasher.Write([]byte(fmt.Sprintf("%x", keybytes)))
 	keybyteshash := fmt.Sprintf("%x", srv.Hasher.Sum(nil))
@@ -65,10 +82,55 @@ func TestBzzResource(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	if !bytes.Equal(b, []byte(keybyteshash)) {
-		t.Fatalf("resource update hash mismatch, expected '%s' got '%s'", keybyteshash, b)
+	rsrcResp := &resourceResponse{}
+	err = json.Unmarshal(b, rsrcResp)
+	if err != nil {
+		t.Fatalf("data %s could not be unmarshaled: %v", b, err)
+	}
+	if rsrcResp.Update.Hex() != keybyteshash {
+		t.Fatalf("Response resource key mismatch, expected '%s', got '%s'", keybyteshash, rsrcResp.Resource)
+	}
+
+	// get manifest
+	url = fmt.Sprintf("%s/bzz-raw:/%s", srv.URL, rsrcResp.Manifest)
+	resp, err = http.Get(url)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("err %s", resp.Status)
+	}
+	b, err = ioutil.ReadAll(resp.Body)
+	if err != nil {
+		t.Fatal(err)
+	}
+	manifest := &api.Manifest{}
+	err = json.Unmarshal(b, manifest)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(manifest.Entries) != 1 {
+		t.Fatalf("Manifest has %d entries", len(manifest.Entries))
+	}
+	if manifest.Entries[0].Hash != rsrcResp.Resource {
+		t.Fatalf("Expected manifest path '%s', got '%s'", keybyteshash, manifest.Entries[0].Hash)
+	}
+
+	// get bzz manifest transparent resource resolve
+	url = fmt.Sprintf("%s/bzz:/%s", srv.URL, rsrcResp.Manifest)
+	resp, err = http.Get(url)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("err %s", resp.Status)
+	}
+	b, err = ioutil.ReadAll(resp.Body)
+	if err != nil {
+		t.Fatal(err)
 	}
-	t.Logf("creatreturn %v / %v", keybyteshash, b)
 
 	// get latest update (1.1) through resource directly
 	url = fmt.Sprintf("%s/bzz-resource:/%x", srv.URL, keybytes)

swarm/api/manifest.go

@@ -70,6 +70,23 @@ func (a *Api) NewManifest() (storage.Key, error) {
 	return key, err
 }
 
+// Manifest hack for supporting Mutable Resource Updates from the bzz: scheme
+// see swarm/api/api.go:Api.Get() for more information
+func (a *Api) NewResourceManifest(resourceKey string) (storage.Key, error) {
+	var manifest Manifest
+	entry := ManifestEntry{
+		Hash:        resourceKey,
+		ContentType: ResourceContentType,
+	}
+	manifest.Entries = append(manifest.Entries, entry)
+	data, err := json.Marshal(&manifest)
+	if err != nil {
+		return nil, err
+	}
+	key, _, err := a.Store(bytes.NewReader(data), int64(len(data)))
+	return key, err
+}
+
 // ManifestWriter is used to add and remove entries from an underlying manifest
 type ManifestWriter struct {
 	api   *Api

swarm/network/protocol_test.go

@@ -95,7 +95,11 @@ func newBzzBaseTester(t *testing.T, n int, addr *BzzAddr, spec *protocols.Spec,
 	cs := make(map[string]chan bool)
 
 	srv := func(p *BzzPeer) error {
-		defer close(cs[p.ID().String()])
+		defer func() {
+			if cs[p.ID().String()] != nil {
+				close(cs[p.ID().String()])
+			}
+		}()
 		return run(p)
 	}
 

swarm/storage/dbstore.go

@@ -695,7 +695,7 @@ func (s *DbStore) get(key Key) (chunk *Chunk, err error) {
 		chunk = NewChunk(key, nil)
 		decodeData(data, chunk)
 	} else {
-		err = ErrNotFound
+		err = ErrChunkNotFound
 	}
 
 	return
@@ -708,8 +708,8 @@ func newMockGetDataFunc(mockStore *mock.NodeStore) func(key Key) (data []byte, e
 	return func(key Key) (data []byte, err error) {
 		data, err = mockStore.Get(key)
 		if err == mock.ErrNotFound {
-			// preserve ErrNotFound error
-			err = ErrNotFound
+			// preserve ErrChunkNotFound error
+			err = ErrChunkNotFound
 		}
 		return data, err
 	}

swarm/storage/dbstore_test.go

@@ -142,8 +142,8 @@ func testDbStoreNotFound(t *testing.T, mock bool) {
 	defer db.close()
 
 	_, err = db.Get(ZeroKey)
-	if err != ErrNotFound {
-		t.Errorf("Expected ErrNotFound, got %v", err)
+	if err != ErrChunkNotFound {
+		t.Errorf("Expected ErrChunkNotFound, got %v", err)
 	}
 }
 

swarm/storage/dpa.go

@@ -48,8 +48,8 @@ const (
 )
 
 var (
-	ErrNotFound = errors.New("not found")
-	ErrFetching = errors.New("chunk still fetching")
+	ErrChunkNotFound = errors.New("chunk not found")
+	ErrFetching      = errors.New("chunk still fetching")
 	// timeout interval before retrieval is timed out
 	searchTimeout = 3 * time.Second
 )

swarm/storage/error.go

@@ -0,0 +1,13 @@
+package storage
+
+const (
+	ErrNotFound = iota
+	ErrIO
+	ErrUnauthorized
+	ErrInvalidValue
+	ErrDataOverflow
+	ErrNothingToReturn
+	ErrInvalidSignature
+	ErrNotSynced
+	ErrCnt
+)

swarm/storage/memstore.go

@@ -214,7 +214,7 @@ func (s *MemStore) Get(hash Key) (chunk *Chunk, err error) {
 		l := hash.bits(bitpos, node.bits)
 		st := node.subtree[l]
 		if st == nil {
-			return nil, ErrNotFound
+			return nil, ErrChunkNotFound
 		}
 		bitpos += node.bits
 		node = st
@@ -232,7 +232,7 @@ func (s *MemStore) Get(hash Key) (chunk *Chunk, err error) {
 			}
 		}
 	} else {
-		err = ErrNotFound
+		err = ErrChunkNotFound
 	}
 
 	return