What is EOS HTTP Server?

EOS HTTP Server is the embedded HTTP server included in EOS SCADA Runtime. When the HTTP server is enabled in the project settings, the server becomes active and starts listening for incoming HTTP requests over the network.

The server status can be monitored through the HTTP SRV indicator located in the status bar of the EOS Runtime application, together with the green LED displayed next to it.

An internet browser or HTTP client can be used to send requests to the server's IP address and port. 

http://IP_ADDRESS:PORT/

EOS HTTP Server therefore acts as a gateway between EOS SCADA Runtime, end users and external applications.

The information provided by the server consists primarily of read-only data from the EOS SCADA system.

Integration with EOS Software

Instead of being a standalone web server requiring a separate installation, EOS HTTP Server is designed to operate as an integrated component of applications within the EOS software family.

EOSFastER

When used together with the EOSFastER data acquisition environment, EOS HTTP Server can provide HTTP-based access to collected industrial data.

EOSscadaRT

The HTTP server integrated into EOS SCADA Runtime can provide network access to real-time data within the SCADA system.

EOSVisualER

When used together with EOSVisualER, the system can simplify the transfer of industrial data to web-based applications and external systems.

Supported Data Formats

EOS HTTP Server can respond to HTTP requests in different data formats. This allows the data to be used by various software applications and systems.

JSON

Requested EOS SCADA data can be returned in JSON format. JSON is particularly suitable for integration with software applications and web-based systems.

XML

EOS SCADA data can be retrieved in XML format. XML can be used for structured data exchange between different applications.

HTML Table

Data can be returned directly as an HTML table and displayed through an internet browser.

PNG Graph

Graphs of EOS SCADA data for a specific time range can be generated in PNG format and retrieved through HTTP.

HTTP Commands

EOS HTTP Server supports various HTTP commands for different purposes.

Command Description Output
gettesis Returns the facility or project name. XML
getxml Returns the requested data. XML
getvalue Returns the requested data. JSON
gethtml Returns the requested data as an HTML table. HTML
getgraph Generates a graph of the specified data for a specified time range. PNG 

getxml
getvalue
gethtml
getgraph

Data Selection Parameters

Various parameters can be used together with HTTP commands to specify which data should be retrieved.

  • all
    Returns the current values of all data defined in EOS SCADA.
  • selected
    Returns the current values of the data selected in EOS SCADA.
  • DATA1:DATA2:...
    Returns only the values of the specified data names separated by colons.

For example, to retrieve all data in XML format: 

http://IP_ADDRESS:80/getxml?all

To retrieve selected data in JSON format: 

http://IP_ADDRESS:80/getvalue?selected

Graph Generation

EOS HTTP Server also supports generating graphs of EOS SCADA data in PNG format.

A graph request can include parameters such as the number of data points, data name, time range, graph width, graph height and DPI value. 

number of data points
&
data name
&
time range (minutes)
&
graph width (pixels)
&
graph height (pixels)
&
graph DPI

For example, to retrieve a graph of one data point for the last 10 minutes with a resolution of 640 × 480 pixels: 

http://IP_ADDRESS:80/getgraph?1&DATA_NAME&10&640&480&300

This feature allows EOS SCADA data to be retrieved as graphical output over HTTP without requiring any dedicated SCADA visualization software.

HTTP Usage Examples

EOS HTTP Server can be used through standard HTTP requests.

To retrieve facility or project information: 

http://IP_ADDRESS:80/gettesis

To retrieve all data in XML format: 

http://IP_ADDRESS:80/getxml?all

To retrieve selected data in JSON format: 

http://IP_ADDRESS:80/getvalue?selected

To retrieve data as an HTML table: 

http://IP_ADDRESS:80/gethtml?DATA1:DATA2

To retrieve a graph: 

http://IP_ADDRESS:80/getgraph?1&DATA1&10&640&480&300

Where is EOS HTTP Server Used?

  • Web-based access to SCADA data
  • Industrial data monitoring
  • Web-based applications
  • Data acquisition systems
  • Technical monitoring applications
  • Data transfer to external applications
  • JSON / XML data integration
  • Data visualization through web browsers
  • Graph-based data presentation
  • Lightweight and simple HTTP integrations

EOS HTTP Server provides a simple and direct HTTP interface, particularly when different applications need easy access to data available in an EOS SCADA system.

Summary

EOS HTTP Server is an integrated web server that provides HTTP-based access to real-time data in EOS SCADA systems.

In addition to JSON, XML and HTML table formats, the server also provides PNG graph output, making EOS SCADA data easier to use with different software applications, web applications and end users.

With simple HTTP commands, EOS SCADA data can be accessed without requiring a dedicated communication protocol.

In this respect, EOS HTTP Server provides a practical data access and Web Gateway solution that connects SCADA and data acquisition systems within the EOS software family with web-based applications.