1. 1
La Storia di SignalR
Dalla nascita alla ri-nascita
AzureConference
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2. 2
I creatori
David Fowler Damian Edwards
SignalR nacque nel 2011
Socket.io, release (0.1.0), il 19/03/2010

3. 3
La storia in ASP .NET
Fu portato nel progetto ASP.NET nel 2013.
In quell’anno WebSocket era un protocollo, appena
standardizzato, ma che molti browser non conoscevano.
Si utilizzavano tecnichiche come polling e altre tecniche
come il Server-Side Event non erano ancora
completamente implementate dai browser.
SignalR nacque per risolvere il problema e inserire un
supporto all’interno dello stack ASP .NET. SignalR divenne
una libreria di riferimento per il RealTime.

4. 4
La storia in ASP .NET
SignalR quindi si fa carico di negoziare il miglior
protocollo di trasporto disponibile per la comunicazione.
SignalR, alla nascita, era strettamente accoppiato a jQuery.
Il web di allora lo era quasi interamente.
Altre funzionalità native dello strumento:
• Riconnessione automatica
• Scalabilità chiavi in mano (Service-Bus)

5. 5
La rinascita

6. 6
La rinascita
Nel 2018 viene interamente riscritto.
Nessuna dipendenza con la libreria jQuery.
Scalabilità (Redis – Azure SignalR Service)
Cross-platform
Estendibile
Disponibile dalla versione ASP .NET Core 2.1
Client: Javascript – Typescript – .NET - Node.js - Python
Prossime release: Java e C++
Planning: Go, PHP

7. 7
I pacchetti disponibili per ASP .NET Signlar
ASP .NET:
https://www.nuget.org/packages/Microsoft.AspNet.SignalR/
JavaScript:
https://www.nuget.org/packages/Microsoft.AspNet.SignalR.JS/
C++: https://github.com/SignalR/SignalR-Client-Cpp
NodeJS: None
PHP: None
Go: None
Python: https://pypi.org/project/signalr-client/
Java: https://github.com/SignalR/java-client

8. 8
I pacchetti disponibili per ASP .NET Core Signalr
ASP .NET Core: 'Microsoft.AspNetCore.SignalR.Client' on NuGet
(https://www.nuget.org/packages/Microsoft.AspNetCore.SignalR/)
Java: 'com.microsoft.aspnet:signalr' on Maven
(https://search.maven.org/artifact/com.microsoft.aspnet/signalr)
JavaScript (including NodeJS): '@aspnet/signalr' on NPM
(https://www.npmjs.com/package/@aspnet/signalr)
C++: (Prototype) https://github.com/aspnet/SignalR/tree/master/clients/cpp
(no official release planned yet)
Swift: (Unofficial) SwiftSignalRClient on CocoaPods
(https://github.com/moozzyk/SignalR-Client-Swift)
PHP ?
Go: Planning
Python: Planning
https://github.com/aspnet/SignalR/tree/release/2.2/specs Per contribuire

9. 9
Protocolli di trasporto
Browser supportati, scenari legacy
AzureConference
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10. “A transport is required to have
the following attributes:
Duplex
Binary-safe
Text-safe

11. 14
SignalR
The only transport which fully implements the duplex
requirement is WebSockets
The others are "half-transports" which implement one end of
the duplex connection.
They are used in combination to achieve a duplex connection.

12. 15
SignalR
ASP.NET Core SignalR was built to be a general purpose
RPC(remote procedure call) based communication library.
It supports:
• Multicast
• Broadcast
• Groups
• Bidirectional RPC
• Streaming

13. 16
Server-Sent Events

14. 17
Web Socket

15. 18
Web Socket

16. 19
Forever frame

17. 20
Protocolli di messaggio
Json, msgpack, custom
AzureConference
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18. 21
JSON

19. 22
JSON
{
"arguments":[
{
"To":{
"Username":"demo",
"ConnectionId":"cqvsDNFlhjht7c6-NyWgvQ"
},
"From":{
"Username":"andrea.tosato",
"ConnectionId":"JLn11llArunDqCMmVqFrbg"
},
"TextMessage":"Buongiorno e benvenuto"
}
],
"target":"AddPrivateMessage",
"type":1
}

20. 23
MessagePack
https://msgpack.org/

21. 24
Message Pack vs Json

22. 25
MessagePack
Microsoft.AspNetCore.SignalR.Protocols.MessagePack
Client
@aspnet/signalr-protocol-msgpack
<script src="~/lib/signalr/signalr.js"></script>
<script src="~/lib/msgpack5/msgpack5.js"></script>
<script src="~/lib/signalr/signalr-protocol-msgpack.js"></script>

23. “If you want to implement a
custom message protocol,
ASP.NET Core SignalR has
extensibility points that allow
new protocols to be plugged in

24. Demo
Heart Rate

25. 28
Connessione e trasferimento dati
Negoziazione della connessione, invio
e ricezione dati
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26. 29
Negotiate
{
"connectionId":"nw-Mk2QvXGxS5WyffMao4A",
"availableTransports":[
{
"transport":"WebSockets",
"transferFormats":["Text", "Binary"]
},
{
"transport":"ServerSentEvents",
"transferFormats":["Text"]
},
{
"transport":"LongPolling",
"transferFormats":["Text", "Binary"]
}
]
}

27. 30
Metodi di invio
SendAsync
Fire and forget
metodo da utilizzare nel server
InvokeAsyn
Metodo che assicura l’invio al client.

28. 31
Streaming
ASP.NET Core SignalR supporta streaming valori restituiti
dei metodi del server.
Ciò è utile per scenari in cui verranno inviati frammenti di
dati nel corso del tempo.
Quando un valore restituito viene trasmesso al client, non
appena diventa disponibile, anziché attendere che tutti i dati
diventino disponibili.

29. 32
Streaming – oggetti da utilizzare
ChannelReader<T>
Restituisce un valore non appena disponibile.
ChannelWriter<T>
Consente la scrittura di dati all’interno di uno stream.

30. Demo
Streaming

31. 34
Streaming – Cooming soon
Server To Client (Work)
Client To Server (Cooming soon)

32. 35
Scalare SignalR
Scenari On-Premise
AzureConference
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33. 36
Perchè Scalare?
Server A - IIS
WebApp
Client 1 Client 2 Client 3 Client N

34. 37
Load Balancer
Perchè Scalare?
Server B - IIS
WebApp
Client 1 Client 2 Client 3 Client N
Server A - IIS
WebApp

35. 38
Load Balancer
Perchè Scalare?
Server B - IIS
WebApp
Client 1 Client 2 Client 3 Client N
Server A - IIS
WebApp
Backplane

36. 39
Backplane
Redis - Pub/Sub
https://redis.io/topics/pubsub

37. 40
Backplane
Sticky Sessions

38. 41
Backplane
Round Robin
Round Robin
with Sticky Session
Server A Server B Server A Server B
User 1 User 2 User 1 User 2

39. 42
Backplane
services
.AddSignalR()
.AddRedis("ConnectionString");
Microsoft.AspNetCore.SignalR.Redis

40. 43
Scalare SignalR
Scenari Cloud
AzureConference
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41. 44
Azure SignalR Services
SignalR è un servizio completamente gestito.
puoi implementarlo in un ambiente multiserver senza
preoccuparti di:
• hosting,
• scalabilità,
• bilanciamento del carico
• autenticazione.

42. 45
Azure SignalR Services
More regions. SignalR Service is now available in the
following regions: US East, US East 2, US Central, US West, US
West 2, Canada East, West Europe, North Europe, Southeast
Asia, Australia East, and Japan East. And in the coming
months we will add more regions.
More reliability. The Azure SignalR Service GA offers 99.9%
availability with a service level agreement for production use.
More capacity. During its preview, the SignalR Service was
limited to 10K connections in the Standard Tier. With GA, it
increases to 100K connections per instance. Through
sharding or partitioning, users can configure multiple
instances to handle an even larger scale.

43. 46
Azure SignalR Services – ASP .NET Core
1
2
3

44. 47
API REST
SWAGGER
https://editor.swagger.io/
SWAGGER DOC
https://github.com/Azure/azure-
signalr/blob/dev/docs/swagger/v1.json

45. 48
https://github.com/Azure/azure-signalr/blob/dev/docs/rest-api.md
API REST

46. Demo
Azure Signalr Service

47. 50
Azure SignalR Service
ASP .NET SignalR versione 2.4
Supporto Azure SignalR per scalabilità chiavi in mano
Coming in 2019

48. 51
Serverless
Serveless
AzureConference
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49. 52
Azure SignalR Services – Serverless
1
2

50. 53
Grazie a una estensione per Azure Functions non è
necessario avere la parte server di SignalR su una
applicazione ASP .NET Core.
L’estensione ha grossi limiti, ma per alcuni sceri può essere
utile.
https://github.com/anthonychu/AzureAdvocates.WebJobs.Extensions.SignalRService OLD
Current limitations
•Only supports broadcasting at this time, cannot invoke methods on a subset of connections,
users, or groups
•Functions cannot be triggered by client invocation of server methods (clients need to call an
HTTP endpoint or post messages to a Event Grid, etc, to trigger a function)
https://github.com/Azure/azure-functions-signalrservice-extension NEW
https://www.nuget.org/packages/Microsoft.Azure.WebJobs.Extensions.SignalRService
Azure SignalR Services – Serverless

51. 54
Supported scenarios
•Allow clients to serverlessly connect to a SignalR Service hub
without requiring an ASP.NET Core backend
•Use Azure Functions (any language supported by V2) to broadcast
messages to all clients connected to a SignalR Service hub
Bindings
SignalRConnectionInfo input binding makes it easy to generate the
token required for clients to initiate a connection to Azure SignalR
Service.
SignalR output binding allows messages to be broadcast to an Azure
SignalR Service hub.
Azure SignalR Services – Serverless

52. Demo
Serverless - Desktop

53. 56
Blazor - SignalR
https://blazor.net/community.html
https://blazorchatsample.azurewebsites.net/
https://github.com/conficient/BlazorChatSample

54. 57
Esempio
Creare una chat completa
AzureConference
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55. Demo
Chat

56. 59
Codice demo
https://github.com/andreatosato/RealTime
https://dnsignalr.azurewebsites.net

57. 60
Azure SignalR Service - il WebSocket che tanto ci mancava
ATosato86
andreatosato
andrea.tosato
CloudGen Verona
aspitalia.com
4ward
ANDREA TOSATO