docs/SystemDesign/Client/RPC.md

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## Rpc definition file

We use thrift rpc between client and server, the definition file is :

thrift/src/main/thrift/rpc.thrift

You can add struct and corresponding method in TSIService (service)

## Code generation

```
mvn clean compile -pl service-rpc -am -DskipTests
```

or

```
mvn clean compile -pl thrift
```

Generated codes:

thrift/target/generated-sources/thrift/org/apache/iotdb/service/rpc/thrift

## Implement the new interface

java client is in Session:

session/src/main/java/org/apache/iotdb/session/Session.java

Rpc service implementation is: 

server/src/main/java/org/apache/iotdb/db/service/TSServiceImpl.java