20 gRPC Interview Questions and Answers

gRPC is a high performance, open source RPC framework that can run in any environment. It is used by many large companies, such as Google, Netflix, and Microsoft. If you are interviewing for a position that involves gRPC, it is important to be prepared to answer questions about it. In this article, we will review some of the most common gRPC interview questions and how you should answer them.

gRPC Interview Questions and Answers

Here are 20 commonly asked gRPC interview questions and answers to prepare you for your interview:

1. What is gRPC?

gRPC is a high performance, open source RPC framework that can run in any environment. It is used to build distributed applications and microservices.

2. How does the client-server communication model work in gRPC?

In gRPC, the client-server communication model is based on the concept of a remote procedure call (RPC). With RPC, a client can send a request to a server and the server can execute a procedure and return a response to the client, all without the client needing to know any details about the server or the procedure.

3. Can you explain what a stub class is?

A stub class is a class that contains the methods and data that are needed to make a remote procedure call (RPC). When an RPC is made, the client makes a call to a method on the stub class. The stub class then makes a call to the server, which contains the actual implementation of the method.

4. Can you name some of the main advantages of using gRPC over REST?

gRPC has a number of advantages over REST, including better performance, lower latency, and more efficient data compression. gRPC is also better suited for use in distributed systems, since it uses a more efficient binary protocol that is less susceptible to network issues.

5. What’s the difference between gRPC and REST?

gRPC is a newer technology that uses a binary protocol and focuses on performance, while REST uses a text-based protocol and is more flexible. gRPC is generally faster and more efficient, but REST is more widely adopted and easier to use.

6. Is it true that gRPC supports multiple languages, including C++, Java, Python, Go, Ruby, NodeJS, Objective-C and PHP?

Yes, that is correct. gRPC supports a wide variety of programming languages, making it a versatile tool for building distributed applications.

7. When should you use gRPC instead of other messaging systems like AMQP or MQTT?

gRPC is a great choice for any application that needs low latency, high performance communication. gRPC is also a good choice if you need to support multiple languages or platforms, as it has excellent language interoperability.

8. Are there any disadvantages to using gRPC? If yes, then what are they?

There are a few potential disadvantages to using gRPC. First, it can be difficult to debug because it uses binary encoding. This can make it hard to read the data that is being passed back and forth. Additionally, gRPC can be less compatible with some legacy systems. Finally, gRPC services can be more difficult to load balance than traditional web services.

9. What do you understand about bidirectional streaming in gRPC?

In gRPC, bidirectional streaming allows for full duplex communication – meaning that both the client and server can send and receive data at the same time. This is in contrast to unidirectional streaming, where data can only flow in one direction.

10. Why is gRPC faster than REST APIs?

gRPC is faster than REST APIs because it uses a binary protocol that is optimized for data serialization. This means that less data needs to be transferred over the network, which results in a faster overall performance.

11. What is protobuf?

Protobuf is a language-neutral, platform-neutral, extensible way of serializing structured data for use in communications protocols, data storage, and more.

12. What are the different types of calls supported by gRPC?

There are four different types of calls that are supported by gRPC. These are unary, server streaming, client streaming, and bidirectional streaming. Unary calls are the most basic, and involve a single request and response. Server streaming calls involve a single request but multiple responses from the server. Client streaming calls involve multiple requests from the client but a single response from the server. Bidirectional streaming calls involve multiple requests and responses from both the client and the server.

13. Which one would you prefer: HTTP/1.1 or HTTP/2? Why?

There is no clear answer as to which one is better. It depends on the specific use case. HTTP/1.1 is the more traditional protocol and is more widely supported. HTTP/2 is newer and has some advantages in terms of speed and efficiency.

14. What is HTTP/2? How is it different from HTTP 1.x?

HTTP/2 is a newer version of the HTTP protocol that was designed to address some of the shortcomings of HTTP 1.x. One of the biggest differences is that HTTP/2 uses a multiplexing technique that allows multiple requests to be sent over a single connection, which can lead to faster page loading times. HTTP/2 also uses binary encoding, which is more efficient than the text-based encoding used in HTTP 1.x, and introduces header compression to reduce the size of data that needs to be sent.

15. What are some best practices for using gRPC?

There are a few best practices to keep in mind when using gRPC:

-Keep your message types small and focused
-Avoid using gRPC for one-off requests
-Batch requests together whenever possible
-Use protobufs to define your message types
-Use the gRPC gateway for external access to your gRPC services

16. What are the differences between Thrift and gRPC?

Thrift is a software framework for developing RPC services. gRPC is a modern open source RPC framework that uses HTTP/2 as its transport layer. gRPC is also based on the Google Protocol Buffers serialization format, while Thrift uses its own binary format. gRPC services are typically written in Google’s Go programming language, while Thrift services can be written in any language.

17. What are the different ways in which you can implement authentication with gRPC?

There are a few different ways that you can implement authentication with gRPC. One way is to use SSL/TLS, which will encrypt all of the data that is being sent between the client and the server. Another way is to use a Google API key, which will authenticate the client with the server. Finally, you can also use OAuth2, which is a standard authentication protocol that is often used with gRPC.

18. Is it possible to combine HTTP/1.1 and HTTP/2 on the same port?

Yes, it is possible to combine HTTP/1.1 and HTTP/2 on the same port. This can be done by using a reverse proxy, such as NGINX, which can terminate HTTP/1.1 and HTTP/2 connections on the same port.

19. What are the key features of HTTP/2?

The key features of HTTP/2 are multiplexing, header compression, and server push. Multiplexing allows for multiple requests to be sent over a single connection, which can help reduce latency. Header compression can help reduce the size of data that needs to be sent over the connection, and server push allows the server to send data to the client even before the client has requested it.

20. What are gRPC channels?

Channels are the fundamental abstraction in gRPC. A channel provides a connection to a gRPC server on a specified host and port and is used when creating a client stub (or just “client” in some languages). Channels are safe for concurrent use by multiple goroutines and manage all underlying connections and state for you.