gRPC is a high performance, language-neutral, general RPC framework developed and open sourced by Google. Built on the HTTP/2 standard, gRPC brings many benefits such as bidirectional streaming, flow control, header compression, multiplexing and more. In this session, you will learn about gRPC and how you can use it in your applications.
Governance in SharePoint Premium:What's in the box?
Introduction to gRPC - Mete Atamel - Codemotion Rome 2017
1. A high performance, open-source, universal RPC framework
Mete Atamel
Developer Advocate for Google Cloud
@meteatamel
2. Confidential & ProprietaryGoogle Cloud Platform 2
Mete Atamel
Developer Advocate for Google Cloud
@meteatamel
atamel@google.com
meteatamel.wordpress.com
Please send talk feedback: bit.ly/atamel
@meteatamel
3. Google Cloud Platform
Agenda
Introduction
RPC, motivation for gRPC
gRPC Basics
What is gRPC? Design goals
Some me the code!
HelloWorld gRPC sample and demo
gRPC Benefits
HTTP/2, Protocol Buffers, multi-language support, connection options
Some me more code!
Streaming gRPC sample and demo
@meteatamel
5. Google Cloud Platform
class GreeterService {
String greeating(String text);
}
class GreeterClient {
var greeter = new GreeterService();
greeter.greeting(“World”);
}
Regular Procedure Call @meteatamel
6. Google Cloud Platform
In distributed computing a remote procedure call (RPC) is when a computer
program causes a procedure (subroutine) to execute in another address space
(commonly on another computer on a shared network), which is coded as if it
were a normal (local) procedure call, without the programmer explicitly coding
the details for the remote interaction
That is, the programmer writes essentially the same code whether the subroutine
is local to the executing program, or remote*
Remote Procedure Call (RPC)
*Wikipedia
@meteatamel
8. Google Cloud Platform
How do clients call the service?
How does the server expose the service?
How does the data serialized/deserialized over the wire? XML, JSON, Binary?
What is the nature of the connection? Request/reply, streaming?
What about authentication?
RPC Questions @meteatamel
9. Google Cloud Platform
1. Build your own custom RPC framework
++ Exactly how you like it: I did this with Adobe Flex Data Services!
-- You need to answer the questions earlier & code
2. Use gRPC: A high performance, open-source universal RPC framework
++ Many of the questions already answered & implemented by community
-- You need to buy into gRPC style, gRPC generated code
Choices @meteatamel
12. Google Cloud Platform
For simple services, HTTP REST is probably enough
→ HTTP verbs (GET, POST, PUT, DELETE etc.) are rich enough
→ REST semantics are well understood
For more complex services where efficiency is important, RPC can help
→ Domain specific: imagine a bank transfer scenario
→ More strongly typed experience via stubs
→ Efficiency with HTTP/2, Protocol Buffer
Why not REST? @meteatamel
14. Google Cloud Platform
Stands for gRPC Remote Procedure Calls
A high performance, open source, general purpose standards-based, feature-rich
RPC framework
Open sourced version of Stubby RPC used in Google
Actively developed and production-ready, current version is 1.2.0
What is gRPC? @meteatamel
15. Google Cloud Platform
Services not Objects, Messages not References
Coverage & Simplicity
Free & Open
Interoperability & Reach
General Purpose & Performant
Layered
Payload Agnostic
Streaming
Blocking & Non-Blocking
Cancellation & Timeout
Motivation and Design Principles
grpc.io/blog/principles
@meteatamel
16. Google Cloud Platform
A high level service definition to describe the API using Protocol Buffers
Client and server code generated from the service definition in 10+ languages
Efficiency in serialization with Protocol Buffers and connection with HTTP/2
Connection options: Unary, server-side streaming, client-side streaming,
bi-directional streaming
Authentication options: SSL/TLS, token based authentication
How does it work? @meteatamel
17. Google Cloud Platform
At the high level
Java
Service
gRPC
Service
Python
Service
gRPC
Stub
gRPC
Service
gRPC
Service
GoLang
Service
C++
Service
gRPC
Stub
gRPC
Stub
gRPC
ServicegRPC
Stub
gRPC
Stub
@meteatamel
20. Google Cloud Platform
Generate client and server code to extend from using proto3 compiler
For Java, there is protobuf-maven-plugin for Maven and protobuf-gradle-plugin
for Gradl to help
For .NET, Grpc.Tools.1.0.1 NuGet package has protoc.exe
Step 2: Generate client and server stubs @meteatamel
21. Google Cloud Platform
Create a service implementation extending from generated base class
Create a server with port and using the service implementation
Start the server
Step 3: Create server @meteatamel
22. Google Cloud Platform
Create a channel for the connection
Create a blocking or non-blocking client stub with the channel
Create a request
Send the request using the stub
Handle the responses in sync or async mode
Step 4: Create client @meteatamel
27. Google Cloud Platform
History of HTTP
1991 1993 1995 1997 1999
HTTP/0.9
2001 2003 2005 2007 2009 2011 2013
HTTP/1.0
2015 2017
HTTP/1.1 ?
@meteatamel
28. Google Cloud Platform
New TCP connection per HTTP
connection
Number of parallel HTTP requests
=
Number of TCP connections.
HTTP 1.x: Limited Parallelism @meteatamel
32. Google Cloud Platform
HTTP Headers
Uncompressed plain text headers for
each and every HTTP request
HTTP 1.x: Protocol Overhead @meteatamel
33. Google Cloud Platform
History of HTTP
1991 1993 1995 1997 1999
HTTP/0.9
2001 2003 2005 2007 2009 2011 2013
HTTP/1.0
2015 2017
HTTP/1.1
@meteatamel
SPDY
HTTP/2.0
34. Google Cloud Platform
Released in 2015. Extend (not replace) the semantics of HTTP/1.1
Improve end-user perceived latency
Address the "head of line blocking"
Not require multiple connections
Minimize protocol overhead
HTTP/2 @meteatamel
35. Google Cloud Platform
HTTP/2
Single TCP connection
No Head-of-line blocking
Binary framing layer
Request –> Stream
Header Compression
Transport(TCP)
Application (HTTP/2)
Network (IP)
Session (TLS) [optional]
Binary Framing
HEADERS Frame
DATA Frame
HTTP/2
POST: /upload
HTTP/1.1
Host: www.javaday.org.ua
Content-Type: application/json
Content-Length: 27
HTTP/1.x
{“msg”: “Welcome to 2016!”}
@meteatamel
36. Google Cloud Platform
Stream is a bidirectional flow of bytes within an established connection,
which may carry one or more messages.
Message is a complete sequence of frames that map to a logical request or
response message.
Frame is the smallest unit of communication in HTTP/2, each containing a
frame header, which at a minimum identifies the stream to which the frame
belongs: HEADERS for metadata, DATA for payload, RST_STREAM SETTINGS,
PUSH_PROMISE, PING, GOAWAY, WINDOW_UPDATE, etc.
HTTP/2 Binary Framing @meteatamel
37. Google Cloud Platform
Interleave multiple requests and responses in parallel without blocking on any
one
Use a single TCP connection to deliver multiple requests and responses in
parallel.
Enable flow-control, server push, etc.
HTTP/2 Request/Response Multiplexing
Stream 1
HEADERS
Stream 2
DATA
Stream 3
HEADERS
Stream 3
DATA
Stream 1
DATA
Stream Y
HEADERS
Stream X
DATA
Requests
Responses
HTTP/2 connection
Client Server
@meteatamel
38. Google Cloud Platform
Client and server maintain and
update an indexed list of
previously seen header fields
Indexes are sent for already
seen headers
Values are encoded with a
static Huffman code
HPACK: Header compression for HTTP/2
:method GET
:scheme HTTPS
:host myhost.com
:path /image
custom_header some_value
:method GET
:scheme HTTPS
:host myhost.com
:path /image
custom_header some_value
HEADERS Frame
:method GET
:scheme HTTPS
:host myhost.com
:path /resource
custom_header some_value
Request #2Request #1
:method GET
:scheme HTTPS
:host myhost.com
:path /resource
custom_header some_value
:path /resource
+ indexes for already seen values
HEADERS Frame
@meteatamel
40. Google Cloud Platform
Protocol Buffers
Publishing 50KB messages at
maximum throughput from a
single n1-highcpu-16 GPE VM
instance, using 9 gRPC channels.
More impressive than the
almost 3x increase in
throughput, is that it took only
1/4 of the CPU resources.
11x difference per CPU3x increase in throughput
https://cloud.google.com/blog/big-data/2016/03/announcing-grpc-alpha-for-google-cloud-pubsub
gRPC vs JSON/HTTP for Google Cloud Pub/Sub
@meteatamel
41. Google Cloud Platform
Multi-Language Support
Java/Android
Go
C/C++
C#
Node.js
PHP
Ruby
Python
Objective-C
Service definitions and client libraries
MacOS
Linux
Windows
Android
iOS
Platforms supported
@meteatamel
43. Google Cloud Platform
Connection Options
The client send a
sequence of messages
to the server using a
provided stream.
Once the client has
finished writing the
messages, it waits for
the server to read them
and return its response.
Client streaming
Both sides send a
sequence of messages
using a read-write
stream. The two
streams operate
independently. The
order of messages in
each stream is
preserved.
Bi-di streaming
Unary RPCs where the
client sends a single
request to the server
and gets a single
response back, just like
a normal function call.
Unary
The client sends a
request to the server
and gets a stream to
read a sequence of
messages back.
The client reads from
the returned stream
until there are no more
messages.
Server streaming
@meteatamel