Ethereum experimentations

Some experimentations in the Ethereum ecosystem. This repo include a team project for OT4 course in INSA Lyon.

About the Dockerfile

Build docker image from Dockerfile

docker build . -t ethereum-tp

It will create a new private blackchain called chaine1T (chaine d'inté ;-) ) in the ~/.ethereum directory.

Run a container in detach mode

Lunch the following command from root:

docker run -itd --name ethereum-tp -v $(pwd)/java-projects:/root/java-projects ethereum-tp /bin/bash

Enter in the container

To obtain bash command line interface inside the container: docker exec -it ethereum-tp /bin/bash

Create new ETH account

From ~/.ethereum directory:

cd ~/.ethereum/
geth --datadir chaine1T account new

Save Public address of the key and Path of the secret key file output for future use inside your dApp.

Lunch a node with mining

From the container command line (cf Enter in the container):

cd ~/.ethereum
geth --datadir chaine1T --rpcapi personnal,db,eth,net,web3 --rpc --mine --minerthreads=1 console

Java projects

You can find different Java projects that interact with you private Ethereum blockchain in the java-projects directory:

• HelloSmartWorld: simple app to upload and execute a solidity smart contract on your own blockchain
• Transfere: simple app to transfert eth from an account to another
• Smarties: The team project. Project specs can be found in this file

Compile java project

Go inside the java-projects directory and choose a project. Go inside a project. To compile source code to .jar file (including dependencies), use: mvn clean install To lunch a compiled project: java -cp ./target/X-SNAPSHOT-jar-with-dependencies.jar fr.insa.smarties.Launcher

If a project miss dependencies, add the following code snippet to the pom.xml file in the root of your maven project.

<build>
    <plugins>
        <plugin>
            <artifactId>maven-assembly-plugin</artifactId>
            <executions>
            <execution>
                <phase>package</phase>
                <goals>
                    <goal>single</goal>
                </goals>
            </execution>
            </executions>
            <configuration>
            <descriptorRefs>
                <descriptorRef>jar-with-dependencies</descriptorRef>
            </descriptorRefs>
            </configuration>
        </plugin>
    </plugins>
</build>