pixelproxy

PixelProxy is a single-binary application with a built-in web UI that can:

• Man-in-the-middle devices, reporting stats and state.
• Record and replay data.
• Visualize device state.

It is designed to run on an embedded system in support of a pixel-based installation.

PixelProxy is built on top of the github.com/danjacques/gopushpixels client library.

Unlike gopushpixels, PixelProxy has not been polished very much. My apologies for the crude code, but there is some good and useful stuff in there :)

Screenshots

Installation

NOTE: If pixelproxy is hosted in a private repository. You may need to configure Git (and Go) to download that repo over SSH so it can authenticate:

git config --global url."git@bitbucket.org:".insteadOf "https://bitbucket.org/"

Setup a Go environment and download:

# Setup a Go path (feel free to adjust):
export GOPATH=~/go

# Update PATH to include Go's bin directory.
export PATH=${GOPATH}/bin:${PATH}

# Download the source and dependencies (but do not install).
#
# This also initializes the submodule dependencies.
go get -u -t -d github.com/danjacques/pixelproxy/...

Running from Source

You can run PixelProxy from source with the following command:

# CD into "PixelProxy" project directory.
cd ${GOPATH}/src/github.com/danjacques/pixelproxy

# Run the "pixelproxy" application.
go run github.com/danjacques/pixelproxy/cmd/pixelproxy/main.go

Use the --help flag to list help options. An example debugging command-line might look like:

# Run the "pixelproxy" application with human-readable verbose logging.
go run ./cmd/pixelproxy/main.go \
    -vdebug --production=false --http_addr=0.0.0.0:8080

This will run the PixelProxy server on your system, bound to port 8080. It can then be accessed by visiting: http://localhost:8080 .

Deployment

Prior to deployment, you should bundle up the assets files into a binary filesystem. This can be done by running:

go generate github.com/danjacques/pixelproxy/assets

Now, produce a binary by running:

go install github.com/danjacques/pixelproxy/cmd/...

The binaries will be in ${GOPATH}/bin!

Shutdown Support

PixelProxy has the ability to allow the user to perform system actions. This is implemented by directly executing shell commands. In order to have these actions work as intended:

• The user must have the following commands available on PATH:

  • sudo
  • shutdown

• The user's sudoers config must allow no-password execution of the shutdown command. This can be implemented adding an /etc/sudoers configuration line:

  user_name ALL=(ALL) NOPASSWD: /sbin/shutdown
  

Resources

• Java (canonical): https://github.com/robot-head/PixelPusher-java
• Python: https://github.com/cagerton/pixelpie
• Node: https://github.com/TheThingSystem/node-pixelpusher
• C++: https://github.com/q-depot/Cinder-PixelPusher
• PixelPusher Server: https://github.com/hzeller/pixelpusher-server

TODO

• Instrument with Prometheus via Go client library.