Added minimal /ocs-provider

internal/http/services/loader/loader.go

@@ -30,6 +30,7 @@ import (
 	_ "github.com/cs3org/reva/internal/http/services/metrics"
 	_ "github.com/cs3org/reva/internal/http/services/ocmd"
 	_ "github.com/cs3org/reva/internal/http/services/ocmprovider"
+	_ "github.com/cs3org/reva/internal/http/services/ocsprovider"
 	_ "github.com/cs3org/reva/internal/http/services/owncloud/ocdav"
 	_ "github.com/cs3org/reva/internal/http/services/owncloud/ocs"
 	_ "github.com/cs3org/reva/internal/http/services/preferences"

internal/http/services/ocsprovider/ocsprovider.go

@@ -0,0 +1,122 @@
+// Copyright 2018-2023 CERN
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// In applying this license, CERN does not waive the privileges and immunities
+// granted to it by virtue of its status as an Intergovernmental Organization
+// or submit itself to any jurisdiction.
+
+package ocsprovider
+
+import (
+	"encoding/json"
+	"net/http"
+
+	"github.com/cs3org/reva/pkg/appctx"
+	"github.com/cs3org/reva/pkg/rhttp/global"
+	"github.com/mitchellh/mapstructure"
+	"github.com/rs/zerolog"
+)
+
+func init() {
+	global.Register("ocmprovider", New)
+}
+
+type config struct {
+	WebdavRoot string `mapstructure:"webdav_root" docs:"/remote.php/dav/ocm;The root URL of the WebDAV endpoint to serve OCM shares."`
+}
+
+type ocsDiscoveryData struct {
+	Version  int         `json:"version"`
+	Services ocsServices `json:"services"`
+}
+
+type ocsServices struct {
+	PrivateData      map[string]any `json:"PRIVATE_DATA"`
+	Sharing          map[string]any `json:"SHARING"`
+	FederatedSharing map[string]any `json:"FEDERATED_SHARING"`
+	Provisioning     map[string]any `json:"PROVISIONING"`
+}
+
+type svc struct {
+	data *ocsDiscoveryData
+}
+
+func (c *config) init() {
+	if c.WebdavRoot == "" {
+		// same default as for the /ocm-provider discovery service
+		c.WebdavRoot = "/remote.php/dav/ocm/"
+	}
+	if c.WebdavRoot[len(c.WebdavRoot)-1:] != "/" {
+		c.WebdavRoot += "/"
+	}
+}
+
+func (c *config) prepare() *ocsDiscoveryData {
+	// generates the (static) data structure to be exposed by /ocs-provider:
+	// here we only populate the federated sharing part and leave the rest empty
+	var fedSharingData = map[string]any{
+		"version": 1,
+		"endpoints": map[string]string{
+			"webdav": c.WebdavRoot,
+		},
+	}
+	d := &ocsDiscoveryData{}
+	d.Version = 1
+	d.Services = ocsServices{
+		PrivateData:      map[string]any{},
+		Sharing:          map[string]any{},
+		FederatedSharing: fedSharingData,
+		Provisioning:     map[string]any{},
+	}
+	return d
+}
+
+// New returns a new ocmprovider object, that implements
+// the OCM discovery endpoint specified in
+// https://cs3org.github.io/OCM-API/docs.html?repo=OCM-API&user=cs3org#/paths/~1ocm-provider/get
+func New(m map[string]interface{}, log *zerolog.Logger) (global.Service, error) {
+	conf := &config{}
+	if err := mapstructure.Decode(m, conf); err != nil {
+		return nil, err
+	}
+
+	conf.init()
+	return &svc{data: conf.prepare()}, nil
+}
+
+// Close performs cleanup.
+func (s *svc) Close() error {
+	return nil
+}
+
+func (s *svc) Prefix() string {
+	// this is hardcoded as per OCS specifications
+	return "/ocs-provider"
+}
+
+func (s *svc) Unprotected() []string {
+	return []string{"/"}
+}
+
+func (s *svc) Handler() http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		log := appctx.GetLogger(r.Context())
+		w.Header().Set("Content-Type", "application/json")
+		w.WriteHeader(http.StatusOK)
+		indented, _ := json.MarshalIndent(s.data, "", "   ")
+		if _, err := w.Write(indented); err != nil {
+			log.Err(err).Msg("Error writing to ResponseWriter")
+		}
+	})
+}