File and data storage The files of an app container are unpacked into a read only filesystem mounted via SquashFS, so that the apps cannot save/store data/files in their installation directory at runtime. The app description can be used to specify whether a persistent and/or… Read More
Metadata The app description file must contain a JSON object with the name “plcnextapp”, which describes the properties of the PLCnext Technology App: { “plcnextapp”: { “name”: ““, “identifier”: ““, “version”: ““, “target”: ““, “minfirmware_version”: ““, “manufacturer”: ““, “licensetype”: “”… Read More
Example of a complete app_info.json 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”: “Full20.0 (112.12 DemoVersion)”, “target”:… Read More
App parts The app container can contain various app parts. This allows different app types to be implemented. The app parts are entered as optional entries in the app description. If these parts are present, the PLCnext Runtime (AppManager) reacts accordingly. The app description file must contain… Read More
PLCnext Engineer Solution A PLCnext Engineer Solution contains a complete PLCnext Engineer project configuration as an app part. PLCnext Engineer Solution is called in the following solution. The user of a solution does not need any programming knowledge to use the app. A solution is transferred directly from the PLCnext Store… Read More
Shared Libraries It can happen that an exe file integrated in the app container, such as a Command Line Tool, brings its own Shared Libraries with it and needs them for its execution. Such Shared Libraries can be integrated into the app container and made known to the… Read More
PLCnext Technology Extensions Extensions of the runtime can be integrated into a system in the form of an app. With a PLCnext Technology Extension, the runtime can be extended by the following elements: A process dependent on the runtime (process) A component (component) A Shared Library (library), which usually… Read More
Update Configurations The update process is shown in the following figure: To update an app you need only to install the app container which contains the new app version (without uninstalling the old app version). The update is detected automatically when: An app is… Read More
Command Line Tools A Command Line Tools app part makes it possible to integrate functionalities (cmd tools) into a system that are usable via the command line and that can be started from a shell without specifying the full path to the tool executable binary. Necessary additions… Read More
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 device. For this topic the container engine Podman is used in conjunction with systemd to allow efficient and reliable management of containerized applications,… Read More
