swarm/storage/mru: Client-side MRU signatures (#784)

* swarm/storage/mru: Add embedded publickey and remove ENS dep

This commit breaks swarm, swarm/api...
but tests in swarm/storage/mru pass

* swarm: Refactor swarm, swarm/api to mru changes, make tests pass

* swarm/storage/mru: Remove self from recv, remove test ens vldtr

* swarm/storage/mru: Remove redundant test, expose ResourceHash mthd

* swarm/storage/mru: Make HeaderGetter mandatory + godoc fixes

* swarm/storage: Remove validator prefix for metadata chunk

* swarm/storage/mru: Use Address instead of PublicKey

* swarm/storage/mru: Change index from name to metadata chunk addr

* swarm/storage/mru: Refactor swarm/api/... to MRU index changes

* swarm/storage/mru: Refactor cleanup

* swarm/storage/mru: Rebase cleanup

* swarm: Use constructor for GenericSigner MRU in swarm.go

* swarm/storage: Change to BMTHash for MRU hashing

* swarm/storage: Reduce loglevel on chunk validator logs

* swarm/storage/mru: Delint

* swarm: MRU Rebase cleanup

* swarm/storage/mru: client-side mru signatures

Rebase to PR #668 and fix all conflicts

* swarm/storage/mru:  refactor and documentation

* swarm/resource/mru: error-checking  tests for parseUpdate/newUpdateChunk

* swarm/storage/mru: Added resourcemetadata tests

* swarm/storage/mru: Added tests  for UpdateRequest

* swarm/storage/mru: more test coverage for UpdateRequest and comments

* swarm/storage/mru: Avoid fake chunks in parseUpdate()

* swarm/storage/mru: Documented resource.go extensively

moved some functions where they make most sense

* swarm/storage/mru: increase test coverage for UpdateRequest and

variable name changes throughout to increase consistency

* swarm/storage/mru: moved default timestamp to NewCreateRequest-

* swarm/storage/mru: lookup refactor

* swarm/storage/mru: added comments and renamed raw flag to rawmru

* swarm/storage/mru: fix receiver typo

* swarm/storage/mru: refactored update chunk new/create

* swarm/storage/mru:  refactored signature digest to avoid malleability

* swarm/storage/mru: optimize update data serialization

* swarm/storage/mru: refactor and cleanup

* swarm/storage/mru: add timestamp struct and serialization

* swarm/storage/mru: fix lint error and mark some old code for deletion

* swarm/storage/mru: remove unnecessary variable

* swarm/storage/mru: Added more comments throughout

* swarm/storage/mru: Refactored metadata chunk layout + extensive error...

* swarm/storage/mru: refactor cli parser
Changed resource info output to JSON

* swarm/storage/mru: refactor serialization for extensibility

refactored error messages to NewErrorf

* swarm/storage/mru: Moved Signature to resource_sign.
Check Sign errors in server tests

* swarm/storage/mru: Remove isSafeName() checks

* swarm/storage/mru: scrubbed off all references to "block" for time

* swarm/storage/mru: removed superfluous isSynced() call.

* swarm/storage/mru: remove isMultihash() and ToSafeName functions

* swarm/storage/mru: various fixes and comments

* swarm/storage/mru: decoupled cli for independent create/update
* Made resource name optional
* Removed unused LookupPrevious

* swarm/storage/mru: Decoupled resource create / update & refactor

* swarm/storage/mru: Fixed some comments as per issues raised in PR #743

* swarm/storage/mru: Cosmetic changes as per #743 comments

* swarm/storage/mru: refct request encoder/decoder > marshal/unmarshal

* swarm/storage/mru: Cosmetic changes as per review in #748

* swarm/storage/mru: removed timestamp proof placeholder

* swarm/storage/mru: cosmetic/doc/fixes changes as per comments in #704

* swarm/storage/mru: removed unnecessary check in Handler.update

* swarm/storage/mru: Implemented Marshaler/Unmarshaler iface in Request

* swarm/storage/mru: Fixed linter error

* swarm/storage/mru: removed redundant address in signature digest

* swarm/storage/mru: fixed bug: LookupLatestVersionInPeriod not working

* swarm/storage/mru: Unfold Request creation API for create or update+create
set common time source for mru package

* swarm/api/http: fix HandleGetResource error variable shadowed
when requesting a resource that does not exist

* swarm/storage/mru: Add simple check to detect duplicate updates

* swarm/storage/mru: moved Multihash() to the right place.

* cmd/swarm: remove unneeded clientaccountmanager.go

* swarm/storage/mru: Changed some comments as per reviews in #784

* swarm/storage/mru: Made SignedResourceUpdate.GetDigest() public

* swarm/storage/mru: cosmetic changes as per comments in #784

* cmd/swarm: Inverted --multihash flag default

* swarm/storage/mru: removed Verify from SignedResourceUpdate.fromChunk

* swarm/storage/mru: Moved validation code out of serializer
Cosmetic / comment changes

* swarm/storage/mru: Added unit tests for UpdateLookup

* swarm/storage/mru: Increased coverage of metadata serialization

* swarm/storage/mru: Increased test coverage of updateHeader serializers

* swarm/storage/mru: Add resourceUpdate serializer test

2 files changed, 247 insertions, 0 deletions

diff --git a/swarm/api/client/client.go b/swarm/api/client/client.go
index ef6222435..b3a5e929d 100644
--- a/swarm/api/client/client.go
+++ b/swarm/api/client/client.go
@@ -35,6 +35,7 @@ import (
 	"strings"
 
 	"github.com/ethereum/go-ethereum/swarm/api"
+	"github.com/ethereum/go-ethereum/swarm/storage/mru"
 )
 
 var (
@@ -562,3 +563,89 @@ func (c *Client) MultipartUpload(hash string, uploader Uploader) (string, error)
 	}
 	return string(data), nil
 }
+
+// CreateResource creates a Mutable Resource with the given name and frequency, initializing it with the provided
+// data. Data is interpreted as multihash or not depending on the multihash parameter.
+// startTime=0 means "now"
+// Returns the resulting Mutable Resource manifest address that you can use to include in an ENS Resolver (setContent)
+// or reference future updates (Client.UpdateResource)
+func (c *Client) CreateResource(request *mru.Request) (string, error) {
+	responseStream, err := c.updateResource(request)
+	if err != nil {
+		return "", err
+	}
+	defer responseStream.Close()
+
+	body, err := ioutil.ReadAll(responseStream)
+	if err != nil {
+		return "", err
+	}
+
+	var manifestAddress string
+	if err = json.Unmarshal(body, &manifestAddress); err != nil {
+		return "", err
+	}
+	return manifestAddress, nil
+}
+
+// UpdateResource allows you to set a new version of your content
+func (c *Client) UpdateResource(request *mru.Request) error {
+	_, err := c.updateResource(request)
+	return err
+}
+
+func (c *Client) updateResource(request *mru.Request) (io.ReadCloser, error) {
+	body, err := request.MarshalJSON()
+	if err != nil {
+		return nil, err
+	}
+
+	req, err := http.NewRequest("POST", c.Gateway+"/bzz-resource:/", bytes.NewBuffer(body))
+	if err != nil {
+		return nil, err
+	}
+
+	res, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return nil, err
+	}
+
+	return res.Body, nil
+
+}
+
+// GetResource returns a byte stream with the raw content of the resource
+// manifestAddressOrDomain is the address you obtained in CreateResource or an ENS domain whose Resolver
+// points to that address
+func (c *Client) GetResource(manifestAddressOrDomain string) (io.ReadCloser, error) {
+
+	res, err := http.Get(c.Gateway + "/bzz-resource:/" + manifestAddressOrDomain)
+	if err != nil {
+		return nil, err
+	}
+	return res.Body, nil
+
+}
+
+// GetResourceMetadata returns a structure that describes the Mutable Resource
+// manifestAddressOrDomain is the address you obtained in CreateResource or an ENS domain whose Resolver
+// points to that address
+func (c *Client) GetResourceMetadata(manifestAddressOrDomain string) (*mru.Request, error) {
+
+	responseStream, err := c.GetResource(manifestAddressOrDomain + "/meta")
+	if err != nil {
+		return nil, err
+	}
+	defer responseStream.Close()
+
+	body, err := ioutil.ReadAll(responseStream)
+	if err != nil {
+		return nil, err
+	}
+
+	var metadata mru.Request
+	if err := metadata.UnmarshalJSON(body); err != nil {
+		return nil, err
+	}
+	return &metadata, nil
+}
diff --git a/swarm/api/client/client_test.go b/swarm/api/client/client_test.go
index e68147ab2..dc608e3f1 100644
--- a/swarm/api/client/client_test.go
+++ b/swarm/api/client/client_test.go
@@ -25,8 +25,12 @@ import (
 	"sort"
 	"testing"
 
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/swarm/api"
 	swarmhttp "github.com/ethereum/go-ethereum/swarm/api/http"
+	"github.com/ethereum/go-ethereum/swarm/multihash"
+	"github.com/ethereum/go-ethereum/swarm/storage/mru"
 	"github.com/ethereum/go-ethereum/swarm/testutil"
 )
 
@@ -354,3 +358,159 @@ func TestClientMultipartUpload(t *testing.T) {
 		checkDownloadFile(file)
 	}
 }
+
+func newTestSigner() (*mru.GenericSigner, error) {
+	privKey, err := crypto.HexToECDSA("deadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeef")
+	if err != nil {
+		return nil, err
+	}
+	return mru.NewGenericSigner(privKey), nil
+}
+
+// test the transparent resolving of multihash resource types with bzz:// scheme
+//
+// first upload data, and store the multihash to the resulting manifest in a resource update
+// retrieving the update with the multihash should return the manifest pointing directly to the data
+// and raw retrieve of that hash should return the data
+func TestClientCreateResourceMultihash(t *testing.T) {
+
+	signer, _ := newTestSigner()
+
+	srv := testutil.NewTestSwarmServer(t, serverFunc)
+	client := NewClient(srv.URL)
+	defer srv.Close()
+
+	// add the data our multihash aliased manifest will point to
+	databytes := []byte("bar")
+
+	swarmHash, err := client.UploadRaw(bytes.NewReader(databytes), int64(len(databytes)), false)
+	if err != nil {
+		t.Fatalf("Error uploading raw test data: %s", err)
+	}
+
+	s := common.FromHex(swarmHash)
+	mh := multihash.ToMultihash(s)
+
+	// our mutable resource "name"
+	resourceName := "foo.eth"
+
+	createRequest, err := mru.NewCreateUpdateRequest(&mru.ResourceMetadata{
+		Name:      resourceName,
+		Frequency: 13,
+		StartTime: srv.GetCurrentTime(),
+		Owner:     signer.Address(),
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	createRequest.SetData(mh, true)
+	if err := createRequest.Sign(signer); err != nil {
+		t.Fatalf("Error signing update: %s", err)
+	}
+
+	resourceManifestHash, err := client.CreateResource(createRequest)
+
+	if err != nil {
+		t.Fatalf("Error creating resource: %s", err)
+	}
+
+	correctManifestAddrHex := "6d3bc4664c97d8b821cb74bcae43f592494fb46d2d9cd31e69f3c7c802bbbd8e"
+	if resourceManifestHash != correctManifestAddrHex {
+		t.Fatalf("Response resource key mismatch, expected '%s', got '%s'", correctManifestAddrHex, resourceManifestHash)
+	}
+
+	reader, err := client.GetResource(correctManifestAddrHex)
+	if err != nil {
+		t.Fatalf("Error retrieving resource: %s", err)
+	}
+	defer reader.Close()
+	gotData, err := ioutil.ReadAll(reader)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !bytes.Equal(mh, gotData) {
+		t.Fatalf("Expected: %v, got %v", mh, gotData)
+	}
+
+}
+
+// TestClientCreateUpdateResource will check that mutable resources can be created and updated via the HTTP client.
+func TestClientCreateUpdateResource(t *testing.T) {
+
+	signer, _ := newTestSigner()
+
+	srv := testutil.NewTestSwarmServer(t, serverFunc)
+	client := NewClient(srv.URL)
+	defer srv.Close()
+
+	// set raw data for the resource
+	databytes := []byte("En un lugar de La Mancha, de cuyo nombre no quiero acordarme...")
+
+	// our mutable resource name
+	resourceName := "El Quijote"
+
+	createRequest, err := mru.NewCreateUpdateRequest(&mru.ResourceMetadata{
+		Name:      resourceName,
+		Frequency: 13,
+		StartTime: srv.GetCurrentTime(),
+		Owner:     signer.Address(),
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	createRequest.SetData(databytes, false)
+	if err := createRequest.Sign(signer); err != nil {
+		t.Fatalf("Error signing update: %s", err)
+	}
+
+	resourceManifestHash, err := client.CreateResource(createRequest)
+
+	correctManifestAddrHex := "cc7904c17b49f9679e2d8006fe25e87e3f5c2072c2b49cab50f15e544471b30a"
+	if resourceManifestHash != correctManifestAddrHex {
+		t.Fatalf("Response resource key mismatch, expected '%s', got '%s'", correctManifestAddrHex, resourceManifestHash)
+	}
+
+	reader, err := client.GetResource(correctManifestAddrHex)
+	if err != nil {
+		t.Fatalf("Error retrieving resource: %s", err)
+	}
+	defer reader.Close()
+	gotData, err := ioutil.ReadAll(reader)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !bytes.Equal(databytes, gotData) {
+		t.Fatalf("Expected: %v, got %v", databytes, gotData)
+	}
+
+	// define different data
+	databytes = []byte("... no ha mucho tiempo que vivía un hidalgo de los de lanza en astillero ...")
+
+	updateRequest, err := client.GetResourceMetadata(correctManifestAddrHex)
+	if err != nil {
+		t.Fatalf("Error retrieving update request template: %s", err)
+	}
+
+	updateRequest.SetData(databytes, false)
+	if err := updateRequest.Sign(signer); err != nil {
+		t.Fatalf("Error signing update: %s", err)
+	}
+
+	if err = client.UpdateResource(updateRequest); err != nil {
+		t.Fatalf("Error updating resource: %s", err)
+	}
+
+	reader, err = client.GetResource(correctManifestAddrHex)
+	if err != nil {
+		t.Fatalf("Error retrieving resource: %s", err)
+	}
+	defer reader.Close()
+	gotData, err = ioutil.ReadAll(reader)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !bytes.Equal(databytes, gotData) {
+		t.Fatalf("Expected: %v, got %v", databytes, gotData)
+	}
+
+}