This repository contains documentation for creating PLCnext app containers as well as demo PLCnext Technology Apps for different app types including their source files.
For full documentation on how to create PLCnext Technology Apps and package them into the corresponding app container, refer to the guide Building a PLCnext Control Function Extension available in the PLCnext Store - Info Center.
A PLCnext App must contain a Metadata-App-part and at least one optional App-part. | 9 | Update Configurations | Used to enable auto update mode, keep apps persistent/temporary data on update or to run an update shell script after installing the new app version | Optional |
| # | App-Part | Description | Type | Firmware support |
|---|---|---|---|---|
| 1 | Metadata | App meta information such as identifier and version | Mandatory | From version 19.0.0 |
| 2 | PLCnext Engineer App | Contains a complete PLCnext Engineer project configuration (solution app) | Optional | From version 19.0.0 |
| 3 | Command line tools | A command line tool can be integrated into a PLCnext system in the form of an app. The command line tool can then be started from a shell without specifying the full path. | Optional | From version 19.3.0 |
| 4 | Shared libraries | Shared libraries can be integrated into the app container and made known to the Linux system when the app is installed/activated | Optional | From version 19.0.0 ❗ Obsoleted: Support is discarded and removed from firmware versions >= 2025.0.x |
| 5 | Linux Daemons | A (Linux) daemon (exe) can be integrated into a PLCnext system in the form of an app | Optional | From version 19.3.0 ❗ Obsoleted: Support is discarded and removed from firmware versions >= 2025.0.x |
| 6 | PLCnext Extensions | Extensions of the PLCnext runtime can be integrated into a PLCnext system in the form of an app. With a PLCnext extension, the PLCnext runtime can be extended by the following elements:
|
Optional | From version 19.3.0 |
| 7 | Configuration of the PLCnext Runtime services | PLCnext system services can be enabled/disabled with this app part | Optional | From version 19.3.0 |
| 8 | File- / Data-Storage | When necessary, it is used to specify whether a persistent and/or temporary location is required for the App | Optional | From version 19.3.0 Support for "directoriesToCreate" from firmware version 2025.0.x |
| 9 | OCI container | This app part provides the possibility for simplified integration and run of OCI (Open Container Initiative) container images of apps on the PLCnext Technology device. For this topic the container engine Podman is used in conjunction with systemd to allow efficient and reliable management of containerized applications, leveraging Podman's rootless and deamonless architecture while maintaining full control over service management through systemd. | Optional | From version 2025.0.x |
The following shows the contents of an app description file in which all types of app parts are configured by way of example:
{
"plcnextapp": {
"name": "Full Multipart App",
"identifier": "00000000000000",
"version": "Full 20.0 (112.12 DemoVersion)",
"target": "AXC F 2152",
"minfirmware_version": "20.0.0",
"manufacturer":"Phoenix Contact",
"licensetype":"Full",
"linkToAppPage":"https://www.plcnextstore.com/testapp",
"additionalInfo":"[{}]"
},
"engineerapp": {
"folder": "/arp/PCWE"
},
"cmdtools":
[
{
"path" : "/bin/DemoCmdTool"
},
{
"path" : "<Path to cmd tool executable binary>"
}
],
"plcnextextensions" :
[
{
"acfconfigpath" : "/PLCnextRuntimeDaemon.acf.config"
},
{
"acfconfigpath" : "<path to PLCnext extension .acf.config file>"
}
],
"datastorage": {
"persistentdata": true,
"temporarydata" : true,
"directoriesToCreate": {
"temporary": [
{
"path": "<folder name/path>"
},
{
"path": "/folder2"
}
],
"persistent": [
{
"path": "<folder name/path>"
},
{
"path": "/folder3"
}
],
}
},
"ocicontainer":
{
"quadletFiles" :
[
{
"type": "Main",
"path": "/path/to/unitFile.pod"
},
{
"type": "Dependency",
"path": "/path/to/unitFile.network"
},
{ "path": "<path to quadlet file>", "type": "<Main/Dependency>" }
],
"environmentVariables":
[
{
"name": "varName1",
"value": "1"
},
{
"name": "varName2",
"value": "2"
}
],
"images":
[
{
"name" : "<name>",
"id": "<idHash>",
"path" : "<path to image file>"
}
]
},
"plcnextservices":
[
{
"service": "<Service ID>",
"action" : "EXCLUSIVE_ACCESS"
},
{
"service": "WBM",
"action" : "MUST_HAVE"
},
{
"service" : "OPCUA",
"action" : "MUST_NOT_HAVE"
}
],
"updateconfigs": {
"autoupdate_enabled": true,
"keep_persistentdata": true,
"keep_temporarydata" : false,
"post_updatescript": "<Path to app update script>"
}
}
Note: Up to firmware version 2025.0, the app parts Linux Daemons and Shared Libraries were supported. If these app parts are included, the following entries also belong in the app_info.json:
{
"linuxdaemons": [
{
"path": "/bin/daemon1exe",
"cmdargs": "arg1 arg2 ... argN",
"starttime": "40"
},
{
"path": "<Path to daemon executable binary>",
"cmdargs": "<arg1 arg2 ... argN>",
"starttime": "99",
"initScriptTemplate": "<Path to own template file>"
}
],
"sharedlibs": [
{
"libpath": "/lib/sharedlib1.so"
},
{
"libpath": "<Path to shared library binary>"
}
]
}This table describes the demo app examples in the git project folder DemoApps
| # | Demo App | Description | Sources |
|---|---|---|---|
| 1 | PLCnext Engineer App | The demo app with an engineer part (solution app) contains a simple solution for flashing an LED (controlling a digital output) in an AXL F DO16 I/O module. The I/O module is controlled by the controller (AXC F 2152) via Axioline F | DemoCmdToolApp |
| 2 | Command Line Tool App | To demonstrate an app with a CmdTool App-Part a simple tool was developed, which is installed in an app and displays a text message on the console when called from the command line | DemoEngineerApp |
| 3 | Linux shared library App | n/a yet | n/a |
| 4 | Linux daemon App | In the SampleLinuxDaemon app the simple program "SampleLinuxDaemon" is started as a Linux daemon, which permanently reads the current time stamp in an endless loop every second and writes it into a log file linuxDaemonOut.log. | SampleLinuxDaemonApp |
| 5 | PLCnext Extensions App | Contains two examples for PLCnext Extensions Apps:
|
PlcnextSampleRuntimeApp WbmPlcnextComponentApp |
| 6 | PLCnext services configuration App | In the demo app for configuring PLCnext system services, the WBM-PLCnext component is switched off. For this the action "MUST_NOT_HAVE" is configured for the Plcnext service with the ID "WBM", therefore the name "SC_WBM-MNH" is selected for the app. | DemoPlcnextServicesConfigApp |
| 7 | Data Storage | The procedure for using and configuring a Data Storage App Part is explained in the demo apps "Demo PLCnext Runtime App" and "Demo Linux Daemon App" | PlcnextSampleRuntimeApp SampleLinuxDaemonApp |
| 8 | Update configs | The update configs demo App contains an App container to update demo App SampleLinuxDaemonApp from app version 123.11.6.0 to 123.11.6.9 | SampleLinuxDaemonUpdateApp |
| 9 | OCI Container | This will be a simple example showcasing selected features of Container Apps. | Soon to be published as an individual repository/project |