nextcloud-spreed-signaling/capabilities.go

213 lines
5.7 KiB
Go

/**
* Standalone signaling server for the Nextcloud Spreed app.
* Copyright (C) 2022 struktur AG
*
* @author Joachim Bauch <bauch@struktur.de>
*
* @license GNU AGPL version 3 or any later version
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package signaling
import (
"context"
"encoding/json"
"fmt"
"io"
"log"
"net/http"
"net/url"
"strings"
"sync"
"time"
)
const (
// Name of the "Talk" app in Nextcloud.
AppNameSpreed = "spreed"
// Name of capability to enable the "v3" API for the signaling endpoint.
FeatureSignalingV3Api = "signaling-v3"
// Cache received capabilities for one hour.
CapabilitiesCacheDuration = time.Hour
)
type capabilitiesEntry struct {
nextUpdate time.Time
capabilities map[string]interface{}
}
type Capabilities struct {
mu sync.RWMutex
version string
pool *HttpClientPool
entries map[string]*capabilitiesEntry
}
func NewCapabilities(version string, pool *HttpClientPool) (*Capabilities, error) {
result := &Capabilities{
version: version,
pool: pool,
entries: make(map[string]*capabilitiesEntry),
}
return result, nil
}
type CapabilitiesVersion struct {
Major int `json:"major"`
Minor int `json:"minor"`
Micro int `json:"micro"`
String string `json:"string"`
Edition string `json:"edition"`
ExtendedSupport bool `json:"extendedSupport"`
}
type CapabilitiesResponse struct {
Version CapabilitiesVersion `json:"version"`
Capabilities map[string]map[string]interface{} `json:"capabilities"`
}
func (c *Capabilities) getCapabilities(key string) (map[string]interface{}, bool) {
c.mu.RLock()
defer c.mu.RUnlock()
now := time.Now()
if entry, found := c.entries[key]; found && entry.nextUpdate.After(now) {
return entry.capabilities, true
}
return nil, false
}
func (c *Capabilities) setCapabilities(key string, capabilities map[string]interface{}) {
now := time.Now()
entry := &capabilitiesEntry{
nextUpdate: now.Add(CapabilitiesCacheDuration),
capabilities: capabilities,
}
c.mu.Lock()
defer c.mu.Unlock()
c.entries[key] = entry
}
func (c *Capabilities) loadCapabilities(ctx context.Context, u *url.URL) (map[string]interface{}, error) {
key := u.String()
if caps, found := c.getCapabilities(key); found {
return caps, nil
}
capUrl := *u
if !strings.Contains(capUrl.Path, "ocs/v2.php") {
if !strings.HasSuffix(capUrl.Path, "/") {
capUrl.Path += "/"
}
capUrl.Path = capUrl.Path + "ocs/v2.php/cloud/capabilities"
} else if pos := strings.Index(capUrl.Path, "/ocs/v2.php/"); pos >= 0 {
capUrl.Path = capUrl.Path[:pos+11] + "/cloud/capabilities"
}
log.Printf("Capabilities expired for %s, updating", capUrl.String())
client, pool, err := c.pool.Get(ctx, &capUrl)
if err != nil {
log.Printf("Could not get client for host %s: %s", capUrl.Host, err)
return nil, err
}
defer pool.Put(client)
req, err := http.NewRequestWithContext(ctx, "GET", capUrl.String(), nil)
if err != nil {
log.Printf("Could not create request to %s: %s", &capUrl, err)
return nil, err
}
req.Header.Set("Accept", "application/json")
req.Header.Set("OCS-APIRequest", "true")
req.Header.Set("User-Agent", "nextcloud-spreed-signaling/"+c.version)
resp, err := client.Do(req)
if err != nil {
return nil, err
}
defer resp.Body.Close()
ct := resp.Header.Get("Content-Type")
if !strings.HasPrefix(ct, "application/json") {
log.Printf("Received unsupported content-type from %s: %s (%s)", capUrl.String(), ct, resp.Status)
return nil, ErrUnsupportedContentType
}
body, err := io.ReadAll(resp.Body)
if err != nil {
log.Printf("Could not read response body from %s: %s", capUrl.String(), err)
return nil, err
}
var ocs OcsResponse
if err := json.Unmarshal(body, &ocs); err != nil {
log.Printf("Could not decode OCS response %s from %s: %s", string(body), capUrl.String(), err)
return nil, err
} else if ocs.Ocs == nil || ocs.Ocs.Data == nil {
log.Printf("Incomplete OCS response %s from %s", string(body), u)
return nil, fmt.Errorf("incomplete OCS response")
}
var response CapabilitiesResponse
if err := json.Unmarshal(*ocs.Ocs.Data, &response); err != nil {
log.Printf("Could not decode OCS response body %s from %s: %s", string(*ocs.Ocs.Data), capUrl.String(), err)
return nil, err
}
capa, found := response.Capabilities[AppNameSpreed]
if !found {
log.Printf("No capabilities received for app spreed from %s: %+v", capUrl.String(), response)
return nil, nil
}
log.Printf("Received capabilities %+v from %s", capa, capUrl.String())
c.setCapabilities(key, capa)
return capa, nil
}
func (c *Capabilities) HasCapabilityFeature(ctx context.Context, u *url.URL, feature string) bool {
caps, err := c.loadCapabilities(ctx, u)
if err != nil {
log.Printf("Could not get capabilities for %s: %s", u, err)
return false
}
featuresInterface := caps["features"]
if featuresInterface == nil {
return false
}
features, ok := featuresInterface.([]interface{})
if !ok {
log.Printf("Invalid features list received for %s: %+v", u, featuresInterface)
return false
}
for _, entry := range features {
if entry == feature {
return true
}
}
return false
}