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<h1 align="center">
  <br>
   <img src="https://plc4x.apache.org/images/apache_plc4x_logo.png" 
   alt="Apache PLC4X Logo" title="Apache PLC4X Logo"/>
  <br>
</h1>
<h3 align="center">The Industrial IoT adapter</h3>
<h4 align="center">The ultimate goal of PLC4X is to create a set of libraries, that allow unified access to any type of
 PLC</h4>

***

# Table of contents

  * [About PLC4X](#about-apache-plc4x)
  * [Getting Started](#getting-started)
  * [Developers](#developers)
  * [Community](#community)
  * [Contributing](#contributing)
  * [Licensing](#licensing)

***

## About Apache PLC4X

Apache PLC4X is an effort to create a set of libraries for communicating with industrial grade programmable logic controllers (PLCs) in a uniform way.
We are planning on shipping libraries for usage in:

1. Java
2. Go
3. C/C++ (not ready for usage)
4. Python (not ready for usage)
5. C# (.Net) (not ready for usage)

PLC4X also integrates with other Apache projects, such as:

* [Apache Calcite](https://calcite.apache.org/)
* [Apache Camel](https://camel.apache.org/)
* [Apache Edgent](https://edgent.apache.org/)
* [Apache Kafka-Connect](https://kafka.apache.org)
* [Apache Karaf](https://karaf.apache.org/)
* [Apache NiFi](https://nifi.apache.org/)

## Getting started

Depending on the programming language, the usage will differ, therefore please go to the 
[Getting Started](https://plc4x.apache.org/users/gettingstarted.html) on the PLC4X website to look up 
the language of choice.

### Java

NOTE: Currently the Java version which supports building of all parts of Apache PLC4X is exactly Java 11
(Higher versions can't build the Logstash integration and lower versions can't build the CMake dependent parts).

See the PLC4J user guide on the website to start using PLC4X in your Java application:
[https://plc4x.apache.org/users/plc4j/gettingstarted.html](https://plc4x.apache.org/users/plc4j/gettingstarted.html)

## Developers

### Environment

Currently the project is configured to require the following software:

1. Java 8 JDK: For running Maven in general as well as compiling the Java and Scala modules `JAVA_HOME` configured to
 point to that.
2. libpcap/WinPcap for raw socket tests in Java or use of `passive-mode` drivers
3. (Optional) [https://www.graphviz.org/](Graphviz): For generating the graphs in the documentation
4. Git (even when working on the source distribution)

With this setup you will be able to build the Java part of PLC4X excluding the "proxy" drivers and servers.
For a full build of PLC4X with all options the following has to be provided:

#### Linux

On a clean Ubuntu 18.04 the following software needs to be installed:

```
    sudo apt install python-setuptools gcc g++ make libpcap-dev
```

If you're building a source-distribution and haven't installed git yet, be sure to do so:

```
    sudo apt install git
```

In order to build the .Net version, please install the .Net package according to this guide:

https://dev.to/carlos487/installing-dotnet-core-in-ubuntu-1804-7lp

#### Mac

Make sure `Homebrew` ist installed in order to update `Bison` to a newer version (the version 2.3 installed per default is too old)

```
    /usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
```

Then update `Bison`:

```
    brew install bison
    brew link bison --force
    echo 'export PATH="/usr/local/opt/bison/bin:$PATH"' >> ~/.bash_profile
```

Install `Python 2.7`:

```
    brew install python@2
```

Be sure to re-open the command window or the changes will not apply.

If you're going to build the `with-dotnet` profile you also need to install DotNet.
Please download it from: https://dotnet.microsoft.com/download and run the installer.

LibPCAP is also installed via Homebrew:

```
    brew install libpcap
```

#### Windows

Some tools need to be installed before being able to build on Windows:

* WinBuilds (for `with-cpp`, `with-proxies` profiles)
* Bison (for `with-cpp` profiles)
* Flex (for `with-cpp` profiles)
* Python 2.7 (for `with-python`, `with-proxies` profiles)
* Dotnet (for `with-dotnet` profiles)
* WinPCAP
* OpenSSL

We have tested `WinBuilds` with the bundle of: http://win-builds.org/doku.php/download_and_installation_from_windows
Run the installer as "Administrator" or you won't be able to install it to "C:\Program Files" or the 32 Bit counterpart.
When running the installer, make sure to select the options:
* Native Windows
* x86_64
Not quite sure which elements are really needed, better just install all of them.
If the installer fails to do something complaining about having to use a different mirror, enter "http://win-builds.org/1.5.0" as mirror address.

WARNING: If you don't use the installer version of the distribution. The build will probably fail and it will be pretty
impossible to see the problem. When manually executing the command, a popup will appear complaining about not being able
to find some DLL. So if you are having these problems, please try using the installer instead of manually unpacking
the archive.

For `Bison`, please download the Setup installer version from here: http://gnuwin32.sourceforge.net/packages/bison.htm (When using the zip version the bison.exe couldn't find some DLL files)
It seems the official 2.4.1 version has issues when installed in a directory which's path contains spaces. Please make sure you replace the exe with a patched version form here: http://marin.jb.free.fr/bison/bison-2.4.1-modified.zip
(More infos on this issue here: https://sourceforge.net/p/gnuwin32/bugs/473/)

Please download the `Flex` compiler from here: http://gnuwin32.sourceforge.net/packages/flex.htm (Ideally download the binary zip distribution)

You can get `Python` from here: https://www.python.org/downloads/release/python-2716/

For `.Net`, you need the `Developer Pack` in order to build .Net applications. So be sure to get a reasonably fresh installation from https://dotnet.microsoft.com

If you're building a source-distribution and haven't installed git yet, be sure to do so.

The Windows version of the PCAP library can be found here: https://sourceforge.net/projects/winpcap413-176/
(In order to read PCAPNG files we require a libpcap version 1.1.0 or greater. The default
Windows version is 1.0. At this location there is a patched version based on libpcap 1.7.4)

Last not least we need to install OpenSSL, which is available from here: https://indy.fulgan.com/SSL/
The letter at the end of the version is sort of a "sub-minor" version, so I usually just take the version with the highest letter.

Make sure the `bin` directories of containing the executables `mingw32-make.exe`, `bison.exe` and `flex.exe` are all on your systems `PATH` as well as the directory containing the `openssl.exe`.

### Getting Started

You must have at least Java 8 installed on your system and connectivity to Maven Central
(for downloading external third party dependencies). However in order to build all parts
of PLC4X exactly Java 11 is required. Maven 3.6 is required to build, so be sure it's installed and available on your system. 

NOTE: There is a convenience Maven-Wrapper installed in the repo, when used, this automatically downloads and installs Maven. If you want to use this, please use `./mvnw` or `mvnw` instead of the normal `mvn` command.

Build PLC4X Java jars and install them in your local maven repository

```
mvn install # add -DskipTests to omit running the tests
```

You can now construct Java applications that use PLC4X. The PLC4X examples
are a good place to start and are available inside the `plc4j/examples`
directory.

The `Go` drivers can be built by enabling the `with-go` profile:

```
mvn -P with-go install  # add -DskipTests to omit running the tests
```

The `C++` drivers are still under development and still not really usable. 
Therefore, they are located in the so-called `sandbox`. 
If you want to build them, this has to be enabled by activating the `with-sandbox` and `with-cpp` maven profiles:

```
mvn -P with-sandbox,with-cpp install  # add -DskipTests to omit running the tests
```

Same applies for the `C# / .Net` implementation with `with-dotnet` profiles.

```
mvn -P with-sandbox,with-dotnet install  # add -DskipTests to omit running the tests
```

The Python implementation is currently in a somewhat unclean state and still needs refactoring.
In order to be able to build the Python module, you currently need to activate the:
`with-sandbox`, `with-python` and `with-proxies` profiles.

```
mvn -P with-sandbox,with-python,with-proxies install  # add -DskipTests to omit running the tests
```

In order to build everything the following command should work:

```
mvn -P with-go,with-boost,with-cpp,with-dotnet,with-logstash,with-proxies,with-python,with-sandbox install
```

## Community

Join the PLC4X community by using one of the following channels. We'll be glad to help!

### Mailing Lists

Subscribe to the following mailing lists: 
* Apache PLC4X Developer List: [dev-subscribe@plc4x.apache.org](mailto:dev-subscribe@plc4x.apache.org)
* Apache PLC4X Commits List: [commits-subscribe@plc4x.apache.org](mailto:commits-subscribe@plc4x.apache.org)
* Apache PLC4X Jira Notification List: [issues-subscribe@plc4x.apache.org](mailto:issues-subscribe@plc4x.apache.org)

See also: [https://plc4x.apache.org/mailing-lists.html](https://plc4x.apache.org/mailing-lists.html)

### Twitter

Get the latest PLC4X news on Twitter: [https://twitter.com/ApachePlc4x](https://twitter.com/ApachePlc4x)

## Contributing

There are multiple forms in which you can become involved with the PLC4X project.

These usually are, but are not limited to:

* Submitting Pull Requests
* Filing Bug-Reports
* Active communication on our mailing lists
* Promoting the project (articles, blog posts, talks at conferences)
* Documentation

We are a very friendly bunch and don’t be afraid to step forward.
If you'd like to contribute to PLC4X, have a look at our 
[contribution guide](https://plc4x.apache.org/developers/contributing.html)!


## Licensing

Apache PLC4X is released under the Apache License Version 2.0.
