Use the HelloWorld plugin

This tutorial shows you how to use the HelloWorld plugin, which exposes a JSON-RPC endpoint to return a greeting message in Spanish.

The plugin interface is implemented in Go and Java. The plugin can reload changes from its JSON configuration.

Prerequisites

• GoQuorum built from source
• Gox installed

Build the plugin distribution file

1. Clone the plugin repository:

   git clone --recursive https://github.com/ConsenSys/quorum-plugin-hello-world.git
   cd quorum-plugin-hello-world

2. Use the Go implementation of the plugin:

   cd go
   make

   quorum-plugin-hello-world-1.0.0.zip is now created in the build directory. The file hello-world-plugin-config.json is the JSON configuration file for the plugin.

3. Rename quorum-plugin-hello-world-1.0.0.zip according to your operating system:

   Linux

   quorum-plugin-hello-world-1.0.0-linux-amd64.zip

   Intel MacOS

   quorum-plugin-hello-world-1.0.0-darwin-amd64.zip

Start GoQuorum with plugin support

1. Navigate to your GoQuorum installation directory. Copy the HelloWorld plugin distribution file and its JSON configuration hello-world-plugin-config.json to build/bin.

2. Create geth-plugin-settings.json:

   cat > build/bin/geth-plugin-settings.json <<EOF
   {
    "baseDir": "./build/bin",
    "providers": {
      "helloworld": {
        "name":"quorum-plugin-hello-world",
        "version":"1.0.0",
        "config": "file://./build/bin/hello-world-plugin-config.json"
      }
    }
   }
   EOF
   note

   For the configured locations, ./ means that you start from the working directory, from where the program is launched.

3. Run geth with the plugin:

   PRIVATE_CONFIG=ignore \
   geth \
       --nodiscover \
       --verbosity 5 \
       --networkid 10 \
       --raft \
       --raftjoinexisting 1 \
       --datadir ./build/_workspace/test \
       --http \
       --http.api eth,debug,admin,net,web3,plugin@helloworld \
       --plugins file://./build/bin/geth-plugin-settings.json \
       --plugins.skipverify

   Run ps -ef | grep helloworld to reveal the HelloWorld plugin process.

Test the plugin

1. Test the HelloWorld plugin using the following command:

   curl HTTP request

   curl -X POST http://localhost:8545 \
       -H "Content-type: application/json" \
       --data '{"jsonrpc":"2.0","method":"plugin@helloworld_greeting","params":["Quorum Plugin"],"id":1}'

   JSON result

   { "jsonrpc": "2.0", "id": 1, "result": "Hello Quorum Plugin!" }

2. Update the plugin configuration build/bin/hello-world-plugin-config.json to support the es language (Spanish).

3. Reload the plugin using the following command:

   curl HTTP request

   curl -X POST http://localhost:8545 \
       -H "Content-type: application/json" \
       --data '{"jsonrpc":"2.0","method":"admin_reloadPlugin","params":["helloworld"],"id":1}'

   JSON result

   { "jsonrpc": "2.0", "id": 1, "result": true }

4. Re-run the HelloWorld plugin:

   curl HTTP request

   curl -X POST http://localhost:8545 \
       -H "Content-type: application/json" \
       --data '{"jsonrpc":"2.0","method":"plugin@helloworld_greeting","params":["Quorum Plugin"],"id":1}'

   JSON result

   { "jsonrpc": "2.0", "id": 1, "result": "Hola Quorum Plugin!" }