3. BACKEND (C++ AND JAVA) Create client libraries to interact with selected Message Broker, preferred Qpid over AMQP, but can be any JMS Broker.

Libraries must have classes to:

• Send a message to MQ
• Receive message from MQ
• Persist Messages in a Database (choose Columns appropriate)
• Return invalid Message to Sender

We would like to see working solution and review code, project structure, tests. Please consider > one of these two options:

• Create and share your git repository
• (or) Send, via email, project sources and instructions how to start it

1. Project structure: Build tools, libraries, source, cmake project
2. Send a message to MQ: Class BSender
3. Receive message from MQ: Class BReceiver
4. Persist Messages in a Database Class Backend:

• Return invalid Message to Sender: not jet implemented
• Tests: for lack of modern test framework. With more time and reason i would look into googletest.

I have tested this with windows10 but Linux should work as well.

You can build localy with cmake if you have the libqpid-proton-cpp.so and sqlite3.so. Then Cmake is required.

Alternatively you can use Docker for building qpid_proton and backend and testing. Here I describe the Docker approch.

• Docker

git clone https://github.com/ersteller/backend.git --recurse-submodules
git submodule update --init

cd backend && mkdir build

docker build --rm  . -t builder:latest -f ./dev/Dockerfile

# Windows PS:
docker run -it -v  ${pwd}/build:/build -v ${pwd}:/project --name builder builder:latest /bin/bash

# Linux: 
docker run -it -v  $(pwd)/build:/build -v $(pwd):/project --name builder builder:latest /bin/bash

(OPTIONAL): To build qpid-cpp in docker

mkdir /project/libs/qpid-cpp/build -p && cd /project/libs/qpid-cpp/build && cmake .. && make

mkdir /project/libs/qpid-proton/build -p && cd /project/libs/qpid-proton/build && cmake .. && make

(OPTIONAL): To build qpid proton python bindings

cd /project/libs/qpid-proton/build && cmake .. -DSYSINSTALL_PYTHON=ON -DSYSINSTALL_BINDINGS=OFF

# Release build
cd /build && cmake /project/backend/ && make

# Debug build with symbols unoptimized
cd /build && cmake -DCMAKE_BUILD_TYPE=Debug /project/backend/ && make 

To start and stop a local broker call following script on your host machine This broker will have a queue named "examples" ready

./dev/start_broker.sh
./dev/stop_broker.sh

To run the application get your IP (to tell backend where the broker is) with "ipconfig" or "ip -a" call the binary in docker with the following command.

# syntax
./backend //<yourIp>:5672 examples
# example
./backend //192.168.178.56:5672 examples

There should be 6 messages in the database.db now. You can verify the content with the following command

echo "SELECT * from messagelog;" | sqlite3 database.db

Debugging in docker container is streight forward

1. Make sure the builder container is running.
2. Replace the ip in .vscode/launch.json with your ip. "args": ["//192.168.178.56:5672", "examples"],
3. Open vs code on the project next to the README.md and press F5 (cpp vscode extension required)