swarm/api: refactor and improve HTTP API (#3773)

This PR deprecates the file related RPC calls in favour of an improved HTTP API.

The main aim is to expose a simple to use API which can be consumed by thin
clients (e.g. curl and HTML forms) without the need for complex logic (e.g.
manipulating prefix trie manifests).

swarm/api/api.go

@@ -17,6 +17,7 @@
 package api
 
 import (
+	"errors"
 	"fmt"
 	"io"
 	"net/http"
@@ -70,86 +71,50 @@ func (self *Api) Store(data io.Reader, size int64, wg *sync.WaitGroup) (key stor
 type ErrResolve error
 
 // DNS Resolver
-func (self *Api) Resolve(hostPort string, nameresolver bool) (storage.Key, error) {
-	log.Trace(fmt.Sprintf("Resolving : %v", hostPort))
-	if hashMatcher.MatchString(hostPort) || self.dns == nil {
-		log.Trace(fmt.Sprintf("host is a contentHash: '%v'", hostPort))
-		return storage.Key(common.Hex2Bytes(hostPort)), nil
+func (self *Api) Resolve(uri *URI) (storage.Key, error) {
+	log.Trace(fmt.Sprintf("Resolving : %v", uri.Addr))
+	if hashMatcher.MatchString(uri.Addr) {
+		log.Trace(fmt.Sprintf("addr is a hash: %q", uri.Addr))
+		return storage.Key(common.Hex2Bytes(uri.Addr)), nil
 	}
-	if !nameresolver {
-		return nil, fmt.Errorf("'%s' is not a content hash value.", hostPort)
+	if uri.Immutable() {
+		return nil, errors.New("refusing to resolve immutable address")
 	}
-	contentHash, err := self.dns.Resolve(hostPort)
+	if self.dns == nil {
+		return nil, fmt.Errorf("unable to resolve addr %q, resolver not configured", uri.Addr)
+	}
+	hash, err := self.dns.Resolve(uri.Addr)
 	if err != nil {
-		err = ErrResolve(err)
-		log.Warn(fmt.Sprintf("DNS error : %v", err))
+		log.Warn(fmt.Sprintf("DNS error resolving addr %q: %s", uri.Addr, err))
+		return nil, ErrResolve(err)
 	}
-	log.Trace(fmt.Sprintf("host lookup: %v -> %v", hostPort, contentHash))
-	return contentHash[:], err
-}
-func Parse(uri string) (hostPort, path string) {
-	if uri == "" {
-		return
-	}
-	parts := slashes.Split(uri, 3)
-	var i int
-	if len(parts) == 0 {
-		return
-	}
-	// beginning with slash is now optional
-	for len(parts[i]) == 0 {
-		i++
-	}
-	hostPort = parts[i]
-	for i < len(parts)-1 {
-		i++
-		if len(path) > 0 {
-			path = path + "/" + parts[i]
-		} else {
-			path = parts[i]
-		}
-	}
-	log.Debug(fmt.Sprintf("host: '%s', path '%s' requested.", hostPort, path))
-	return
-}
-
-func (self *Api) parseAndResolve(uri string, nameresolver bool) (key storage.Key, hostPort, path string, err error) {
-	hostPort, path = Parse(uri)
-	//resolving host and port
-	contentHash, err := self.Resolve(hostPort, nameresolver)
-	log.Debug(fmt.Sprintf("Resolved '%s' to contentHash: '%s', path: '%s'", uri, contentHash, path))
-	return contentHash[:], hostPort, path, err
+	log.Trace(fmt.Sprintf("addr lookup: %v -> %v", uri.Addr, hash))
+	return hash[:], nil
 }
 
 // Put provides singleton manifest creation on top of dpa store
-func (self *Api) Put(content, contentType string) (string, error) {
+func (self *Api) Put(content, contentType string) (storage.Key, error) {
 	r := strings.NewReader(content)
 	wg := &sync.WaitGroup{}
 	key, err := self.dpa.Store(r, int64(len(content)), wg, nil)
 	if err != nil {
-		return "", err
+		return nil, err
 	}
 	manifest := fmt.Sprintf(`{"entries":[{"hash":"%v","contentType":"%s"}]}`, key, contentType)
 	r = strings.NewReader(manifest)
 	key, err = self.dpa.Store(r, int64(len(manifest)), wg, nil)
 	if err != nil {
-		return "", err
+		return nil, err
 	}
 	wg.Wait()
-	return key.String(), nil
+	return key, nil
 }
 
 // Get uses iterative manifest retrieval and prefix matching
 // to resolve path to content using dpa retrieve
 // it returns a section reader, mimeType, status and an error
-func (self *Api) Get(uri string, nameresolver bool) (reader storage.LazySectionReader, mimeType string, status int, err error) {
-	key, _, path, err := self.parseAndResolve(uri, nameresolver)
-	if err != nil {
-		return nil, "", 500, fmt.Errorf("can't resolve: %v", err)
-	}
-
-	quitC := make(chan bool)
-	trie, err := loadManifest(self.dpa, key, quitC)
+func (self *Api) Get(key storage.Key, path string) (reader storage.LazySectionReader, mimeType string, status int, err error) {
+	trie, err := loadManifest(self.dpa, key, nil)
 	if err != nil {
 		log.Warn(fmt.Sprintf("loadManifestTrie error: %v", err))
 		return
@@ -173,32 +138,25 @@ func (self *Api) Get(uri string, nameresolver bool) (reader storage.LazySectionR
 	return
 }
 
-func (self *Api) Modify(uri, contentHash, contentType string, nameresolver bool) (newRootHash string, err error) {
-	root, _, path, err := self.parseAndResolve(uri, nameresolver)
-	if err != nil {
-		return "", fmt.Errorf("can't resolve: %v", err)
-	}
-
+func (self *Api) Modify(key storage.Key, path, contentHash, contentType string) (storage.Key, error) {
 	quitC := make(chan bool)
-	trie, err := loadManifest(self.dpa, root, quitC)
+	trie, err := loadManifest(self.dpa, key, quitC)
 	if err != nil {
-		return
+		return nil, err
 	}
-
 	if contentHash != "" {
-		entry := &manifestTrieEntry{
+		entry := newManifestTrieEntry(&ManifestEntry{
 			Path:        path,
-			Hash:        contentHash,
 			ContentType: contentType,
-		}
+		}, nil)
+		entry.Hash = contentHash
 		trie.addEntry(entry, quitC)
 	} else {
 		trie.deleteEntry(path, quitC)
 	}
 
-	err = trie.recalcAndStore()
-	if err != nil {
-		return
+	if err := trie.recalcAndStore(); err != nil {
+		return nil, err
 	}
-	return trie.hash.String(), nil
+	return trie.hash, nil
 }