Method queryRemoteKeys

keyserver/internal/internal.go:403–465

(
	ctx context.Context, timeout time.Duration, res *api.QueryKeysResponse,
	domainToDeviceKeys map[string]map[string][]string, domainToCrossSigningKeys map[string]map[string]struct{},
)

}

func (a *KeyInternalAPI) queryRemoteKeys(
	ctx context.Context, timeout time.Duration, res *api.QueryKeysResponse,
	domainToDeviceKeys map[string]map[string][]string, domainToCrossSigningKeys map[string]map[string]struct{},
) {
	resultCh := make(chan *gomatrixserverlib.RespQueryKeys, len(domainToDeviceKeys))
	// allows us to wait until all federation servers have been poked
	var wg sync.WaitGroup
	// mutex for writing directly to res (e.g failures)
	var respMu sync.Mutex

	domains := map[string]struct{}{}
	for domain := range domainToDeviceKeys {
		if domain == string(a.ThisServer) {
			continue
		}
		domains[domain] = struct{}{}
	}
	for domain := range domainToCrossSigningKeys {
		if domain == string(a.ThisServer) {
			continue
		}
		domains[domain] = struct{}{}
	}
	wg.Add(len(domains))

	// fan out
	for domain := range domains {
		go a.queryRemoteKeysOnServer(
			ctx, domain, domainToDeviceKeys[domain], domainToCrossSigningKeys[domain],
			&wg, &respMu, timeout, resultCh, res,
		)
	}

	// Close the result channel when the goroutines have quit so the for .. range exits
	go func() {
		wg.Wait()
		close(resultCh)
	}()

	for result := range resultCh {
		for userID, nest := range result.DeviceKeys {
			res.DeviceKeys[userID] = make(map[string]json.RawMessage)
			for deviceID, deviceKey := range nest {
				keyJSON, err := json.Marshal(deviceKey)
				if err != nil {
					continue
				}
				res.DeviceKeys[userID][deviceID] = keyJSON
			}
		}

		for userID, body := range result.MasterKeys {
			res.MasterKeys[userID] = body
		}

		for userID, body := range result.SelfSigningKeys {
			res.SelfSigningKeys[userID] = body
		}