/// <summary>
/// Check whether the record is connected
/// </summary>
/// <param name="record"></param>
/// <param name="ct"></param>
/// <returns></returns>
internal async Task <bool> IsConnectedAsync(INameRecord record,
CancellationToken ct)
{
try {
var stream = await _http.StreamAsync(
CreateUri("/devices/" + record.Id), Http.Get,
async h => {
h.Add(HttpRequestHeader.Authorization.ToString(),
await IoTHubService.GetSasTokenAsync(_hubConnectionString,
3600).ConfigureAwait(false));
h.Add(HttpRequestHeader.UserAgent.ToString(), _clientId);
}, (sc, h) => {
if (sc == HttpStatusCode.NotFound)
{
throw new TransientException();
}
}, ct).ConfigureAwait(false);
using (stream)
using (var sr = new StreamReader(stream))
using (JsonReader reader = new JsonTextReader(sr)) {
var response = (JObject)JToken.ReadFrom(reader);
return(response["connectionState"].ToString().Equals(
"Connected", StringComparison.CurrentCultureIgnoreCase));
}
}
catch (TransientException) {
return(false);
}
catch (Exception e) {
throw ProxyEventSource.Log.Rethrow(e, this);
}
}
/// <summary>
/// Retrieves a single device twin based record from IoT Hub
/// </summary>
/// <param name="record"></param>
/// <param name="ct"></param>
/// <returns></returns>
internal async Task <IoTHubRecord> GetRecordAsync(INameRecord record,
CancellationToken ct)
{
try {
var stream = await _http.StreamAsync(
CreateUri("/twins/" + record.Id), Http.Get,
async h => {
h.Add(HttpRequestHeader.Authorization.ToString(),
await IoTHubService.GetSasTokenAsync(_hubConnectionString,
3600).ConfigureAwait(false));
h.Add(HttpRequestHeader.UserAgent.ToString(), _clientId);
}, (sc, h) => {
if (sc == HttpStatusCode.NotFound)
{
throw new TransientException();
}
}, ct).ConfigureAwait(false);
using (stream)
using (var sr = new StreamReader(stream))
using (JsonReader reader = new JsonTextReader(sr)) {
return(new IoTHubRecord((JObject)JToken.ReadFrom(reader)));
}
}
catch (TransientException) {
ProxyEventSource.Log.RecordRemoved(this, record);
return(null);
}
catch (Exception e) {
throw ProxyEventSource.Log.Rethrow(e, this);
}
}
/// <summary>
/// Constructor creating a method based polled stream.
/// </summary>
/// <param name="iothub"></param>
/// <param name="streamId"></param>
/// <param name="remoteId"></param>
/// <param name="link"></param>
/// <param name="connectionString"></param>
public IoTHubStream(IoTHubService iothub, Reference streamId,
Reference remoteId, INameRecord link, ConnectionString connectionString)
{
_iotHub = iothub;
_streamId = streamId;
_remoteId = remoteId;
_link = link;
ConnectionString = connectionString;
}
/// <summary>
/// Returns the query results async
/// </summary>
/// <param name="sql"></param>
/// <param name="continuation"></param>
/// <param name="ct"></param>
/// <returns></returns>
private async Task <Tuple <string, IEnumerable <IoTHubRecord> > > PagedLookupAsync(
string sql, string continuation, CancellationToken ct)
{
if (string.IsNullOrEmpty(sql))
{
throw ProxyEventSource.Log.ArgumentNull("sql");
}
try {
var uri = new UriBuilder {
Scheme = "https",
Host = _hubConnectionString.HostName,
Path = "/devices/query",
Query = "api-version=" + _apiVersion
};
var stream = await _http.StreamAsync(
CreateUri("/devices/query"), Http.Post,
async h => {
h.Add(HttpRequestHeader.Authorization.ToString(),
await IoTHubService.GetSasTokenAsync(_hubConnectionString,
3600).ConfigureAwait(false));
h.Add(HttpRequestHeader.UserAgent.ToString(), _clientId);
// Add previous continuation if any provided
if (!string.IsNullOrEmpty(continuation))
{
h.Add("x-ms-continuation", continuation);
}
}, (s, h) => {
// get continuation returned if any
if (h.TryGetValues("x-ms-continuation", out var values))
{
continuation = values.FirstOrDefault();
}
else
{
continuation = null;
}
}, ct,
@"{""query"":""" + sql + @"""}", "application/json").ConfigureAwait(false);
using (stream)
using (var sr = new StreamReader(stream))
using (JsonReader reader = new JsonTextReader(sr)) {
var results = JToken.ReadFrom(reader);
return(Tuple.Create(continuation, results.Select(j => new IoTHubRecord((JObject)j))));
}
}
catch (Exception e) {
throw ProxyEventSource.Log.Rethrow(e, this);
}
}
/// <summary>
/// Initialize default provider
/// </summary>
/// <param name="iothub"></param>
public DefaultProvider(ConnectionString iothub)
{
if (iothub == null)
{
throw new ArgumentException("You must provide the iothubowner connection " +
"string, which can be obtained from the Azure IoT Hub portal. You must " +
"then either initialize the DefaultProvider class, or set the _HUB_CS " +
"environment variable.");
}
try {
_iothub = new IoTHubService(iothub);
}
catch (Exception e) {
throw ProxyEventSource.Log.Rethrow(e, this);
}
}
/// <summary>
/// Initialize default provider
/// </summary>
/// <param name="iothub"></param>
public DefaultProvider(string iothub)
{
if (string.IsNullOrEmpty(iothub))
{
iothub = Environment.GetEnvironmentVariable("_HUB_CS");
}
if (string.IsNullOrEmpty(iothub))
{
throw ProxyEventSource.Log.ArgumentNull(nameof(iothub), this);
}
try {
_iothub = new IoTHubService(ConnectionString.Parse(iothub));
}
catch (Exception e) {
throw ProxyEventSource.Log.Rethrow(e, this);
}
}
/// <summary>
/// Deletes an record in the IoT Hub device registry
/// </summary>
/// <param name="record"></param>
/// <param name="ct"></param>
/// <returns></returns>
internal async Task RemoveRecordAsync(INameRecord record,
CancellationToken ct)
{
try {
await _http.CallAsync(
CreateUri("/devices/" + record.Id), Http.Delete,
async h => {
h.Add(HttpRequestHeader.Authorization.ToString(),
await IoTHubService.GetSasTokenAsync(_hubConnectionString,
3600).ConfigureAwait(false));
h.Add(HttpRequestHeader.UserAgent.ToString(), _clientId);
h.IfMatch.Add(new EntityTagHeaderValue(@"""*"""));
},
(sc, h) => { }, ct).ConfigureAwait(false);
}
catch (Exception e) {
ProxyEventSource.Log.HandledExceptionAsInformation(this, e);
}
}
/// <summary>
/// Creates a device in the IoT Hub device registry
/// </summary>
/// <param name="record"></param>
/// <param name="ct"></param>
/// <returns></returns>
internal async Task <IoTHubRecord> AddRecordAsync(INameRecord record,
CancellationToken ct)
{
try {
await _http.CallAsync(CreateUri("/devices/" + record.Id), Http.Put,
async h => {
h.Add(HttpRequestHeader.Authorization.ToString(),
await IoTHubService.GetSasTokenAsync(_hubConnectionString,
3600).ConfigureAwait(false));
h.Add(HttpRequestHeader.UserAgent.ToString(), _clientId);
}, (sc, h) => {
if (sc == HttpStatusCode.Conflict || sc == HttpStatusCode.PreconditionFailed)
{
throw new TransientException();
}
}, ct,
@"{""deviceId"": """ + record.Id + @"""}", "application/json").ConfigureAwait(false);
ProxyEventSource.Log.RecordAdded(this, record);
return(new IoTHubRecord(record));
}
catch (TransientException) {
// Retrieve the twin object and update it
var result = await GetRecordAsync(record, ct).ConfigureAwait(false);
if (result == null)
{
return(null);
}
result.Assign(record);
return(result);
}
catch (Exception e) {
throw ProxyEventSource.Log.Rethrow(e, this);
}
}
/// <summary>
/// Makes a method request from a message
/// </summary>
/// <param name="message"></param>
/// <param name="timeout"></param>
/// <param name="ct"></param>
/// <returns></returns>
public async Task <Message> CallAsync(Message message,
TimeSpan timeout, CancellationToken ct)
{
#if LOG_MESSAGES
var sw = System.Diagnostics.Stopwatch.StartNew();
#endif
#endif
if (string.IsNullOrEmpty(message.DeviceId))
{
throw ProxyEventSource.Log.ArgumentNull("deviceId");
}
var buffer = new MemoryStream();
var request = MethodCallRequest.Create(message, timeout);
request.Encode(buffer, CodecId.Json);
var uri = new UriBuilder {
Scheme = "https",
Host = ConnectionString.HostName,
Path = $"/twins/{WebUtility.UrlEncode(message.DeviceId)}/methods",
Query = "api-version=" + IoTHubService._apiVersion
};
MethodCallResponse response;
try {
var stream = await _http.StreamAsync(uri.Uri, Http.Post, async h => {
h.Add(HttpRequestHeader.Authorization.ToString(),
await IoTHubService.GetSasTokenAsync(ConnectionString,
3600).ConfigureAwait(false));
h.Add(HttpRequestHeader.UserAgent.ToString(), IoTHubService._clientId);
}, (s, h) => { }, ct, Encoding.UTF8.GetString(buffer.ToArray()),
"application/json").ConfigureAwait(false);
using (stream) {
response = Serializable.Decode <MethodCallResponse>(stream, CodecId.Json);
}
}
catch (HttpResponseException hex) {
ProxyEventSource.Log.HandledExceptionAsError(this, hex);
if (hex.StatusCode == HttpStatusCode.NotFound)
{
throw new ProxyNotFound(hex);
}
if (hex.StatusCode == HttpStatusCode.Forbidden)
{
throw new ProxyPermission(hex);
}
if (hex.StatusCode == HttpStatusCode.GatewayTimeout)
{
throw new ProxyTimeout(hex.Message, hex);
}
throw new ProxyException(
$"Remote proxy device method communication failure: {hex.StatusCode}.", hex);
}
catch (OperationCanceledException) {
throw;
}
catch (Exception ex) {
ProxyEventSource.Log.HandledExceptionAsError(this, ex);
throw new ProxyException($"Unknown proxy failure.", ex);
}
#if LOG_MESSAGES
finally {
System.Diagnostics.Trace.TraceInformation(
$" > {sw.Elapsed} < for InvokeDeviceMethodAsync({message})");
}
#endif
if (response.Status != 200)
{
throw ProxyEventSource.Log.Rethrow(
new ProxyException($"Unexpected status {response.Status} returned by proxy."));
}
return(response.Payload);
}
/// <summary>
/// Updates a record in the device registry
/// </summary>
/// <param name="record"></param>
/// <param name="ct"></param>
/// <returns></returns>
private async Task <IoTHubRecord> UpdateRecordAsync(
INameRecord record, CancellationToken ct)
{
var hubRecord = record as IoTHubRecord;
//
// If the record is a generic record, add it first and retrieve the resulting
// twin record from the registry. Then assign the generic record to it and
// see if anything needs patching...
//
if (hubRecord == null)
{
// Create and convert generic record into hub record
hubRecord = await AddRecordAsync(record, ct).ConfigureAwait(false);
if (hubRecord == null)
{
return(null);
}
}
var json = hubRecord.Patch;
if (string.IsNullOrEmpty(json))
{
// Nothing to patch...
return(hubRecord);
}
//
// If we logged changes to the record use the resulting patch json to patch
// up the twin record. If we do not find the record anymore as part of
// patching it, then it was deleted, in which case return null. Otherwise
// return the returned patched up twin record
//
ProxyEventSource.Log.PatchingRecord(this, record, json);
try {
var stream = await _http.StreamAsync(
CreateUri("/twins/" + hubRecord.Id), Http.Patch,
async h => {
h.Add(HttpRequestHeader.Authorization.ToString(),
await IoTHubService.GetSasTokenAsync(_hubConnectionString,
3600).ConfigureAwait(false));
h.Add(HttpRequestHeader.UserAgent.ToString(), _clientId);
h.IfMatch.Add(new EntityTagHeaderValue(@"""*"""));
},
(sc, h) => {
if (sc == HttpStatusCode.NotFound)
{
throw new TransientException();
}
}, ct, json, "application/json").ConfigureAwait(false);
using (stream)
using (var sr = new StreamReader(stream))
using (JsonReader reader = new JsonTextReader(sr)) {
hubRecord = new IoTHubRecord(new IoTHubRecord((JObject)JToken.ReadFrom(reader)));
}
}
catch (TransientException) {
ProxyEventSource.Log.RecordRemoved(this, record);
hubRecord = null;
}
catch (Exception e) {
throw ProxyEventSource.Log.Rethrow(e, this);
}
ProxyEventSource.Log.RecordPatched(this, record, json);
return(hubRecord);
}
