IoMBian Button Handler

This service checks the state of a momentary button connected to a GPIO pin and publishes the information through a ZeroMQ socket (port 5556 by default).

The event list is:

• Single click: "click"
• Double click: "double_click"
• Triple click: "triple_click"
• Many click (more than 3): "many_click"
• Long click (more than 1 sec): "long_click"
• Long long click (more than 5 secs): "long_long_click"

Any ZeroMQ subscriber can listen to those events and act accordingly.

Installation

• Define project name in an environment variable:

PROJECT_NAME=iombian-button-handler

• Clone the repo into a temp folder:

git clone https://github.com/Tknika/${PROJECT_NAME}.git /tmp/${PROJECT_NAME} && cd /tmp/${PROJECT_NAME}

• Create the installation folder and move the appropiate files (edit the user):

sudo mkdir /opt/${PROJECT_NAME}

sudo cp requirements.txt /opt/${PROJECT_NAME}

sudo cp -r src/* /opt/${PROJECT_NAME}

sudo cp systemd/${PROJECT_NAME}.service /etc/systemd/system/

sudo chown -R iompi:iompi /opt/${PROJECT_NAME}

• Create the virtual environment and install the dependencies:

cd /opt/${PROJECT_NAME}

python3 -m venv venv

source venv/bin/activate

pip install --upgrade pip

pip install -r requirements.txt

• Start the script

sudo systemctl enable ${PROJECT_NAME}.service && sudo systemctl start ${PROJECT_NAME}.service

Docker

To build the docker image, from the cloned repository, execute the docker build command in the same level as the Dockerfile.

docker build -t ${IMAGE_NAME}:${IMAGE_VERSION} .

For example: docker build -t iombian-button-handler:latest .

After building the image, execute it with docker run

docker run --name ${CONTAINER_NAME} --privileged --rm -d -p 5556:5556 -e BUTTON_PIN=3 iombian-button-handler:latest

• --name is used to define the name of the created container.

• --privileged is for granting privileges to the docker container. This is needed because the iombian-button-handler needs to create a thread to listen to the button events.

• --rm can be used to delete the container when it stops. This parameter is optional.

• -d is used to run the container detached. This way the container will run in the background. This parameter is optional.

• -p is used to expose the internal 5556 port to the external 5556 port. The 5556 port is where this service will publish the button events. The port is exposed so the published messages can be accesd from outside the containers network.

• -e can be used to define the environment variables:

  • BUTTON_PIN: define the pin of the button of the radpberry pi. Default value is 3.
  • LOG_LEVEL: define the log level for the python logger. This can be NOTSET, DEBUG, INFO, WARNING, ERROR or CRITICAL. Default value is INFO.
  • BUTTON_EVENT_PORT: define the internal port where the button pressing events will be transmitted. The iombian-button-handler will be the publisher on this port. Default port is 5556.

Author

(c) 2021 Aitor Iturrioz Rodríguez

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.