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Use Sequencer API to generate distributed unique and self-incrementing id

What is Sequencer API​

The Sequencer API is used to generate distributed unique, self-incrementing IDs.

The Sequencer API supports the declaration of demand for self-increment, including trend increase (WEAK) and strictly global increment (STRONG)

Quick start​

This example shows how to call Etcd through Layotto to generate a distributed unique, self-increasing id.

The architecture of this example is shown in the figure below, and the processes started are: Etcd, Layotto, and client programs

img.png

step 1. Deploy etcd and Layotto​

With Docker Compose​

You can start etcd and Layotto with docker-compose

cd docker/layotto-etcd
# Start etcd and layotto with docker-compose
docker-compose up -d

Compile locally (not for Windows)​

You can run etcd with Docker, then compile and run Layotto locally.

[!TIP|label: Not for Windows users] Layotto fails to compile under Windows. Windows users are recommended to deploy using docker-compose

step 1.1 Deploy the storage system (Etcd)​

For the deployment of etcd, please refer to etcd's Official Document

Brief description:

Visit https://github.com/etcd-io/etcd/releases to download etcd of the corresponding operating system (docker is also available)

Once the download is finished,execute the command to start:

./etcd

The default listening address is localhost:2379

step 1.2 Run Layotto​

After downloading the project code to the local, switch the code directory and compile:

cd ${project_path}/cmd/layotto
go build

Once finished, the layotto file will be generated in the directory, run it:

./layotto start -c ../../configs/runtime_config.json

step 2. Run the client program and call Layotto to generate a unique id​

Go​

Build and run the golang demo:

 cd ${project_path}/demo/sequencer/common/
 go build -o client
 ./client -s "sequencer_demo"

If the following information is printed, the demo is successful:

Try to get next id.Key:key666 
Next id:next_id:1  
Next id:next_id:2  
Next id:next_id:3  
Next id:next_id:4  
Next id:next_id:5  
Next id:next_id:6  
Next id:next_id:7  
Next id:next_id:8  
Next id:next_id:9  
Next id:next_id:10  
Demo success!

Java​

Download java sdk and examples:

git clone https://github.com/layotto/java-sdk
cd java-sdk

Build the demo:

# build example jar
mvn -f examples-sequencer/pom.xml clean package

Run it:

java -jar examples-sequencer/target/examples-sequencer-jar-with-dependencies.jar

If the following information is printed, the demo is successful:

Try to get next id.Key: examples
Next id: 1
Try to get next id.Key: examples
Next id: 2
Try to get next id.Key: examples
Next id: 3
Try to get next id.Key: examples
Next id: 4
Try to get next id.Key: examples
Next id: 5
Try to get next id.Key: examples
Next id: 6
Try to get next id.Key: examples
Next id: 7
Try to get next id.Key: examples
Next id: 8
Try to get next id.Key: examples
Next id: 9
Try to get next id.Key: examples
Next id: 10

step 3. Stop containers and release resources​

Docker Compose​

If you started etcd and Layotto with docker-compose, you can shut them down as follows:

cd ${project_path}/docker/layotto-etcd
docker-compose stop

Destroy the etcd container​

If you started etcd with Docker, you can destroy the etcd container as follows:

docker rm -f etcd

Next step​

What does this client program do?​

The demo client program uses the SDK provided by Layotto, calls the Layotto Sequencer API, and generates a distributed unique, self-increasing id.

The golang sdk is located in the sdk directory, and the java sdk is in https://github.com/layotto/java-sdk

In addition to using sdk, you can also interact with Layotto directly through grpc in any language you like.

In fact, sdk is only a very thin package for grpc, using sdk is about equal to directly using grpc.

Want to learn more about Sequencer API?​

What does the Sequencer API do, what problems it solves, and in what scenarios should I use it?

If you are confused and want to know more details about the use of Sequencer API, you can read Sequencer API Usage Document

Details later, let's continue to experience other APIs​

Explore other Quickstarts through the navigation bar on the left.