/// <summary>
/// Copy properties from remote web orchestrator
/// </summary>
public void SetValues(WebServerOrchestrator webServerOrchestrator)
{
this.Options = webServerOrchestrator.Options;
this.Setup = webServerOrchestrator.Setup;
this.ConnectionString = webServerOrchestrator.Provider.ConnectionString;
this.ProviderType = webServerOrchestrator.Provider.GetType();
}
/// <summary>
/// Create a new web server orchestrator
/// </summary>
public WebServerOrchestrator CreateWebServerOrchestrator()
{
// Create provicer
var provider = (CoreProvider)Activator.CreateInstance(this.ProviderType);
provider.ConnectionString = this.ConnectionString;
// Create orchestrator
var webServerOrchestrator = new WebServerOrchestrator(provider, this.Options, this.Setup);
return(webServerOrchestrator);
}
private IConverter GetClientConverter(string cs, WebServerOrchestrator serverOrchestrator)
{
try
{
if (string.IsNullOrEmpty(cs))
{
return(null);
}
var clientConverter = serverOrchestrator.Options.Converters.First(c => c.Key == cs);
return(clientConverter);
}
catch
{
throw new HttpConverterNotConfiguredException(serverOrchestrator.Options.Converters.Select(sf => sf.Key));
}
}
/// <summary>
/// Call this method to handle requests on the server, sent by the client
/// </summary>
public async Task HandleRequestAsync(HttpContext context, Action <RemoteOrchestrator> action, CancellationToken cancellationToken)
{
var httpRequest = context.Request;
var httpResponse = context.Response;
var serAndsizeString = string.Empty;
var converter = string.Empty;
if (httpRequest.Method.ToLowerInvariant() == "get")
{
await this.WriteHelloAsync(context, cancellationToken);
return;
}
// Get the serialization and batch size format
if (TryGetHeaderValue(context.Request.Headers, "dotmim-sync-serialization-format", out var vs))
{
serAndsizeString = vs.ToLowerInvariant();
}
// Get the serialization and batch size format
if (TryGetHeaderValue(context.Request.Headers, "dotmim-sync-converter", out var cs))
{
converter = cs.ToLowerInvariant();
}
if (!TryGetHeaderValue(context.Request.Headers, "dotmim-sync-session-id", out var sessionId))
{
throw new HttpHeaderMissingExceptiopn("dotmim-sync-session-id");
}
if (!TryGetHeaderValue(context.Request.Headers, "dotmim-sync-step", out string iStep))
{
throw new HttpHeaderMissingExceptiopn("dotmim-sync-step");
}
var step = (HttpStep)Convert.ToInt32(iStep);
var readableStream = new MemoryStream();
try
{
// Copty stream to a readable and seekable stream
// HttpRequest.Body is a HttpRequestStream that is readable but can't be Seek
await httpRequest.Body.CopyToAsync(readableStream);
httpRequest.Body.Close();
httpRequest.Body.Dispose();
// if Hash is present in header, check hash
if (TryGetHeaderValue(context.Request.Headers, "dotmim-sync-hash", out string hashStringRequest))
{
HashAlgorithm.SHA256.EnsureHash(readableStream, hashStringRequest);
}
// Create a web server remote orchestrator based on cache values
if (this.WebServerOrchestrator == null)
{
this.WebServerOrchestrator = this.WebServerProperties.CreateWebServerOrchestrator();
}
// try get schema from cache
if (this.Cache.TryGetValue <SyncSet>(WebServerProperties.Key, out var cachedSchema))
{
this.WebServerOrchestrator.Schema = cachedSchema;
}
// try get session cache from current sessionId
if (!this.Cache.TryGetValue <SessionCache>(sessionId, out var sessionCache))
{
sessionCache = new SessionCache();
}
// action from user if available
action?.Invoke(this.WebServerOrchestrator);
// Get the serializer and batchsize
(var clientBatchSize, var clientSerializerFactory) = GetClientSerializer(serAndsizeString, this.WebServerOrchestrator);
// Get converter used by client
// Can be null
var clientConverter = GetClientConverter(converter, this.WebServerOrchestrator);
this.WebServerOrchestrator.ClientConverter = clientConverter;
byte[] binaryData = null;
switch (step)
{
case HttpStep.EnsureScopes:
var m1 = await clientSerializerFactory.GetSerializer <HttpMessageEnsureScopesRequest>().DeserializeAsync(readableStream);
var s1 = await this.WebServerOrchestrator.EnsureScopeAsync(m1, sessionCache, cancellationToken).ConfigureAwait(false);
binaryData = await clientSerializerFactory.GetSerializer <HttpMessageEnsureScopesResponse>().SerializeAsync(s1);
await this.WebServerOrchestrator.Provider.InterceptAsync(new HttpMessageEnsureScopesResponseArgs(binaryData)).ConfigureAwait(false);
break;
case HttpStep.SendChanges:
var m2 = await clientSerializerFactory.GetSerializer <HttpMessageSendChangesRequest>().DeserializeAsync(readableStream);
var s2 = await this.WebServerOrchestrator.ApplyThenGetChangesAsync(m2, sessionCache, clientBatchSize, cancellationToken).ConfigureAwait(false);
binaryData = await clientSerializerFactory.GetSerializer <HttpMessageSendChangesResponse>().SerializeAsync(s2);
if (s2.Changes != null && s2.Changes.HasRows)
{
await this.WebServerOrchestrator.Provider.InterceptAsync(new HttpMessageSendChangesResponseArgs(binaryData)).ConfigureAwait(false);
}
break;
case HttpStep.GetChanges:
var m3 = await clientSerializerFactory.GetSerializer <HttpMessageGetMoreChangesRequest>().DeserializeAsync(readableStream);
var s3 = await this.WebServerOrchestrator.GetMoreChangesAsync(m3, sessionCache, cancellationToken);
binaryData = await clientSerializerFactory.GetSerializer <HttpMessageSendChangesResponse>().SerializeAsync(s3);
if (s3.Changes != null && s3.Changes.HasRows)
{
await this.WebServerOrchestrator.Provider.InterceptAsync(new HttpMessageSendChangesResponseArgs(binaryData)).ConfigureAwait(false);
}
break;
case HttpStep.GetSnapshot:
var m4 = await clientSerializerFactory.GetSerializer <HttpMessageSendChangesRequest>().DeserializeAsync(readableStream);
var s4 = await this.WebServerOrchestrator.GetSnapshotAsync(m4, sessionCache, cancellationToken);
binaryData = await clientSerializerFactory.GetSerializer <HttpMessageSendChangesResponse>().SerializeAsync(s4);
if (s4.Changes != null && s4.Changes.HasRows)
{
await this.WebServerOrchestrator.Provider.InterceptAsync(new HttpMessageSendChangesResponseArgs(binaryData)).ConfigureAwait(false);
}
break;
}
// Save schema to cache with a sliding expiration
this.Cache.Set(WebServerProperties.Key, this.WebServerOrchestrator.Schema, this.WebServerProperties.Options.GetServerCacheOptions());
// Save session client to cache with a sliding expiration
this.Cache.Set(sessionId, sessionCache, this.WebServerProperties.Options.GetClientCacheOptions());
// Adding the serialization format used and session id
httpResponse.Headers.Add("dotmim-sync-session-id", sessionId.ToString());
httpResponse.Headers.Add("dotmim-sync-serialization-format", clientSerializerFactory.Key);
// calculate hash
var hash = HashAlgorithm.SHA256.Create(binaryData);
var hashString = Convert.ToBase64String(hash);
// Add hash to header
httpResponse.Headers.Add("dotmim-sync-hash", hashString);
// data to send back, as the response
byte[] data = this.EnsureCompression(httpRequest, httpResponse, binaryData);
await httpResponse.Body.WriteAsync(data, 0, data.Length).ConfigureAwait(false);
}
catch (Exception ex)
{
await WriteExceptionAsync(httpResponse, ex);
}
finally
{
readableStream.Close();
readableStream.Dispose();
}
}
/// <summary>
/// Get an instance of SyncMemoryProvider depending on session id. If the entry for session id does not exists, create a new one
/// </summary>
//private static WebServerOrchestrator GetCachedOrchestrator(HttpContext context, string syncSessionId)
//{
// WebServerOrchestrator remoteOrchestrator;
// var cache = context.RequestServices.GetService<IMemoryCache>();
// if (cache == null)
// throw new HttpCacheNotConfiguredException();
// if (string.IsNullOrWhiteSpace(syncSessionId))
// throw new ArgumentNullException(nameof(syncSessionId));
// // get the sync provider associated with the session id
// remoteOrchestrator = cache.Get(syncSessionId) as WebServerOrchestrator;
// return remoteOrchestrator;
//}
/// <summary>
/// Add a new instance of SyncMemoryProvider, created by DI
/// </summary>
/// <returns></returns>
//private static WebServerOrchestrator AddNewOrchestratorToCacheFromDI(HttpContext context, string syncSessionId)
//{
// var cache = context.RequestServices.GetService<IMemoryCache>();
// if (cache == null)
// throw new HttpCacheNotConfiguredException();
// var remoteOrchestrator = DependencyInjection.GetNewOrchestrator();
// cache.Set(syncSessionId, remoteOrchestrator, TimeSpan.FromHours(1));
// return remoteOrchestrator;
//}
//private static WebServerOrchestrator AddNewOrchestratorToCache(HttpContext context, CoreProvider provider, SyncSetup setup, string sessionId, WebServerOptions options = null)
//{
// WebServerOrchestrator remoteOrchestrator;
// var cache = context.RequestServices.GetService<IMemoryCache>();
// if (cache == null)
// throw new HttpCacheNotConfiguredException();
// remoteOrchestrator = new WebServerOrchestrator(provider, options, setup);
// cache.Set(sessionId, remoteOrchestrator, TimeSpan.FromHours(1));
// return remoteOrchestrator;
//}
//private static WebServerOrchestrator AddNewWebServerOrchestratorToCache(HttpContext context, WebServerOrchestrator webServerOrchestrator, string sessionId)
//{
// var cache = context.RequestServices.GetService<IMemoryCache>();
// if (cache == null)
// throw new HttpCacheNotConfiguredException();
// cache.Set(sessionId, webServerOrchestrator, TimeSpan.FromHours(1));
// return webServerOrchestrator;
//}
private (int clientBatchSize, ISerializerFactory clientSerializer) GetClientSerializer(string serAndsizeString, WebServerOrchestrator serverOrchestrator)
{
try
{
if (string.IsNullOrEmpty(serAndsizeString))
{
throw new Exception();
}
var serAndsize = JsonConvert.DeserializeAnonymousType(serAndsizeString, new { f = "", s = 0 });
var clientBatchSize = serAndsize.s;
var clientSerializerFactory = serverOrchestrator.Options.Serializers[serAndsize.f];
return(clientBatchSize, clientSerializerFactory);
}
catch
{
throw new HttpSerializerNotConfiguredException(serverOrchestrator.Options.Serializers.Select(sf => sf.Key));
}
}
/// <summary>
/// Call this method to handle requests on the server, sent by the client
/// </summary>
public async Task HandleRequestAsync(HttpContext context, Action <RemoteOrchestrator> action, CancellationToken cancellationToken)
{
var httpRequest = context.Request;
var httpResponse = context.Response;
var streamArray = GetBody(httpRequest);
var serAndsizeString = string.Empty;
var converter = string.Empty;
// Get the serialization and batch size format
if (TryGetHeaderValue(context.Request.Headers, "dotmim-sync-serialization-format", out var vs))
{
serAndsizeString = vs.ToLowerInvariant();
}
// Get the serialization and batch size format
if (TryGetHeaderValue(context.Request.Headers, "dotmim-sync-converter", out var cs))
{
converter = cs.ToLowerInvariant();
}
if (!TryGetHeaderValue(context.Request.Headers, "dotmim-sync-session-id", out var sessionId))
{
throw new HttpHeaderMissingExceptiopn("dotmim-sync-session-id");
}
if (!TryGetHeaderValue(context.Request.Headers, "dotmim-sync-step", out string iStep))
{
throw new HttpHeaderMissingExceptiopn("dotmim-sync-step");
}
var step = (HttpStep)Convert.ToInt32(iStep);
try
{
// Create a web server remote orchestrator based on cache values
if (this.WebServerOrchestrator == null)
{
this.WebServerOrchestrator = this.WebServerProperties.CreateWebServerOrchestrator();
}
// try get schema from cache
if (this.Cache.TryGetValue <SyncSet>(WebServerProperties.Key, out var cachedSchema))
{
this.WebServerOrchestrator.Schema = cachedSchema;
}
// try get session cache from current sessionId
if (!this.Cache.TryGetValue <SessionCache>(sessionId, out var sessionCache))
{
sessionCache = new SessionCache();
}
// action from user if available
action?.Invoke(this.WebServerOrchestrator);
// Get the serializer and batchsize
(var clientBatchSize, var clientSerializerFactory) = GetClientSerializer(serAndsizeString, this.WebServerOrchestrator);
// Get converter used by client
// Can be null
var clientConverter = GetClientConverter(converter, this.WebServerOrchestrator);
this.WebServerOrchestrator.ClientConverter = clientConverter;
byte[] binaryData = null;
switch (step)
{
case HttpStep.EnsureScopes:
var m1 = clientSerializerFactory.GetSerializer <HttpMessageEnsureScopesRequest>().Deserialize(streamArray);
var s1 = await this.WebServerOrchestrator.EnsureScopeAsync(m1, sessionCache, cancellationToken).ConfigureAwait(false);
binaryData = clientSerializerFactory.GetSerializer <HttpMessageEnsureScopesResponse>().Serialize(s1);
await this.WebServerOrchestrator.Provider.InterceptAsync(new HttpMessageEnsureScopesResponseArgs(binaryData)).ConfigureAwait(false);
break;
case HttpStep.SendChanges:
var m2 = clientSerializerFactory.GetSerializer <HttpMessageSendChangesRequest>().Deserialize(streamArray);
var s2 = await this.WebServerOrchestrator.ApplyThenGetChangesAsync(m2, sessionCache, clientBatchSize, cancellationToken).ConfigureAwait(false);
binaryData = clientSerializerFactory.GetSerializer <HttpMessageSendChangesResponse>().Serialize(s2);
if (s2.Changes != null && s2.Changes.HasRows)
{
await this.WebServerOrchestrator.Provider.InterceptAsync(new HttpMessageSendChangesResponseArgs(binaryData)).ConfigureAwait(false);
}
break;
case HttpStep.GetChanges:
var m3 = clientSerializerFactory.GetSerializer <HttpMessageGetMoreChangesRequest>().Deserialize(streamArray);
var s3 = this.WebServerOrchestrator.GetMoreChanges(m3, sessionCache, cancellationToken);
binaryData = clientSerializerFactory.GetSerializer <HttpMessageSendChangesResponse>().Serialize(s3);
if (s3.Changes != null && s3.Changes.HasRows)
{
await this.WebServerOrchestrator.Provider.InterceptAsync(new HttpMessageSendChangesResponseArgs(binaryData)).ConfigureAwait(false);
}
break;
case HttpStep.GetSnapshot:
var m4 = clientSerializerFactory.GetSerializer <HttpMessageSendChangesRequest>().Deserialize(streamArray);
var s4 = await this.WebServerOrchestrator.GetSnapshotAsync(m4, sessionCache, cancellationToken);
binaryData = clientSerializerFactory.GetSerializer <HttpMessageSendChangesResponse>().Serialize(s4);
if (s4.Changes != null && s4.Changes.HasRows)
{
await this.WebServerOrchestrator.Provider.InterceptAsync(new HttpMessageSendChangesResponseArgs(binaryData)).ConfigureAwait(false);
}
break;
}
// Save schema to cache with a sliding expiration
this.Cache.Set(WebServerProperties.Key, this.WebServerOrchestrator.Schema, this.WebServerProperties.Options.GetServerCacheOptions());
// Save session client to cache with a sliding expiration
this.Cache.Set(sessionId, sessionCache, this.WebServerProperties.Options.GetClientCacheOptions());
// Adding the serialization format used and session id
httpResponse.Headers.Add("dotmim-sync-session-id", sessionId.ToString());
httpResponse.Headers.Add("dotmim-sync-serialization-format", clientSerializerFactory.Key);
// data to send back, as the response
byte[] data = this.EnsureCompression(httpRequest, httpResponse, binaryData);
await this.GetBody(httpResponse).WriteAsync(data, 0, data.Length).ConfigureAwait(false);
}
catch (Exception ex)
{
await WriteExceptionAsync(httpResponse, ex);
}
finally
{
//if (httpMessage != null && httpMessage.Step == HttpStep.EndSession)
// Cleanup(context.RequestServices.GetService(typeof(IMemoryCache)), syncSessionId);
}
}