Datanodes

The datanode type determines how data is acquired:

• IoT LoRa types (e.g., uh30, prolora, elliot…) – receive data from ČRA and usually correspond to a specific physical device such as an electricity or water meter.
• HTTP types (e.g., gasnet, spotrebapodpalcem, distribuce24…) – actively retrieve data from external APIs. These don’t always correspond to a single device – data may be aggregated, processed by a service, or a single datanode may serve hundreds of physical devices.

In the user interface, you can configure basic parameters and type-specific properties of the datanode. It is also possible to assign a datanode to a datahub, especially if multiple datahubs are available in the domain.

Main actions:

• Edit Datanode – allows you to modify the parameters of an existing datanode
• Delete Datanode – allows you to delete the selected datanode

Buttons:

• Create Datanode – opens a modal window for creating a new datanode
• Datanode Variables – opens a modal window displaying the datanode’s variables
• Datanode Events – opens a modal window displaying the datanode’s events

Modal window for creating a new datanode

In this window, you can set the datanode parameters:

• Name – the name of the datanode
• Datahub – select the datahub. If there is only one available in the domain, this field is hidden. Otherwise, select the one that matches the datanode's configuration and type.
• Database profile – the datanode’s database profile
• Type – the type of datanode, which determines which properties are configurable
• Datanode type properties – properties specific to the selected datanode type.

If a row is highlighted in red, it is a required field and must be filled in.

  If not highlighted, the property is optional and may remain empty.  
  Some fields may have default values pre-filled.

Modal window showing a list of available datanode variables and their most recent known value in the Mervis system, along with a timestamp.

Modal window displaying the events of the datanode. This shows the current status of the given datanode and is useful for diagnosing datanode errors.

• Description
  • Downloads 15-min measured data (profiles ICC1, ISC1, IKC1, IMC1, ICCS) from EGD Distribuce24 OpenAPI.
• Instructions for obtaining client_id and client_secret
  • Log in to portal.distribuce24.cz using your existing customer credentials (e-mail from registration + password — note this is not the API credentials).
  • Go to the Account Management section.
  • Open the Remote Access - OpenAPI tab.
  • Click the Generate client_id and client_secret button.
• Properties
  • ServerUrlTemplate: template of the base REST API URL (required)
  • UserName: client_id (required)
  • Password: client_secret (required)
  • CommInterval: interval of regular data downloading in TimeSpan format, e.g. 01:00:00 (required)
  • CommTaskCron: optional cron expression for scheduling downloads; takes precedence over CommInterval (optional)
  • Ean: EAN of the consumption point, 18 digits (required)
  • AuthUrlTemplate: URL of the token (OAuth2) endpoint for obtaining the access token (required)

• Description
  • Downloads the export of measured data from the ČEZ Distribuce customer portal.
• Instructions
  • UserName and Password are the login credentials for the ČEZ Distribuce customer portal.
  • Ean = EAN of the consumption point (opmId parameter).
• Properties
  • ServerUrlTemplate: template of the base REST API URL (required)
  • UserName: username for the ČEZ Distribuce portal (required)
  • Password: password for the ČEZ Distribuce portal (required)
  • CommInterval: interval of regular data downloading in TimeSpan format, e.g. 01:00:00 (required)
  • CommTaskCron: optional cron expression for scheduling downloads; takes precedence over CommInterval (optional)
  • Ean: EAN of the consumption point, 18 digits (required)

• Description
  • Downloads consumption profiles from the PREdistribuce portal.
• Instructions
  • UserName and Password are the login credentials for the My Account PREdistribuce portal.
  • Ean = EAN of the consumption point for which consumption profiles are downloaded.
• Properties
  • ServerUrlTemplate: template of the base REST API URL (required)
  • UserName: username for the PREdistribuce portal (required)
  • Password: password for the PREdistribuce portal (required)
  • CommInterval: interval of regular data downloading in TimeSpan format, e.g. 01:00:00 (required)
  • CommTaskCron: optional cron expression for scheduling downloads; takes precedence over CommInterval (optional)
  • Ean: EAN of the consumption point, 18 digits (required)

• Description
  • Downloads JSON data of a single LoRaWAN device from the VisionQ REST API.
• Notes on the URL
  • ServerUrlTemplate contains the placeholder {eui}, which is replaced by the value of DevEui.
• Properties
  • ServerUrlTemplate: template of the base REST API URL (required)
  • UserName: username for logging in to the API (required)
  • Password: password for the API (required)
  • CommInterval: interval of regular data downloading in TimeSpan format, e.g. 01:00:00 (required)
  • CommTaskCron: optional cron expression for scheduling downloads; takes precedence over CommInterval (optional)
  • DevEui: EUI of the LoRaWAN device substituted into {eui} in ServerUrlTemplate (required)

• Description
  • Downloads gas consumption data from the iave.gasnet.cz portal.
• Instructions
  • UserName and Password are the login credentials for the iave.gasnet.cz portal.
  • You can find the Eic in the detail of the consumption/delivery point on the portal.
  • PmId / UpId serve for optional narrowing of the selection of points.
• Properties
  • ServerUrlTemplate: template of the base REST API URL (required)
  • UserName: username for the iave.gasnet.cz portal (required)
  • Password: password for the iave.gasnet.cz portal (required)
  • CommInterval: interval of regular data downloading in TimeSpan format, e.g. 01:00:00 (required)
  • CommTaskCron: optional cron expression for scheduling downloads; takes precedence over CommInterval (optional)
  • Eic: EIC of the gas consumption point, 16 characters - uppercase letters and digits (required)
  • PmId: number of the PM (delivery point) for filtering - optional (optional)
  • UpId: number of the UP (location/consumption point) for filtering - optional (optional)

• Description
  • Downloads water meter data from the Smart API (endpoints /api/SmartData/…).
• Properties
  • ServerUrlTemplate: template of the base REST API URL (required)
  • UserName: username for OAuth2 password grant (required)
  • Password: password for OAuth2 password grant (required)
  • CommInterval: interval of regular data downloading in TimeSpan format, e.g. 01:00:00 (required)
  • CommTaskCron: optional cron expression for scheduling downloads; takes precedence over CommInterval (optional)
  • ClientId: OAuth2 client_id of the application (required)
  • ClientSecret: OAuth2 client_secret of the application (required)
  • CpId: identifier of the consumption point / meter (required)

• Description
  • Downloads both 15-min and daily data from the EGD SMARAGD API (shares the Distribuce24 infrastructure).
• Instructions for obtaining client_id and client_secret
  • Log in to portal.distribuce24.cz using your customer credentials (e-mail from registration + password).
  • Go to the Account Management section.
  • Open the Remote Access - OpenAPI tab.
  • Click the Generate client_id and client_secret button.
• Properties
  • ServerUrlTemplate: template of the base REST API URL (required)
  • UserName: client_id (required)
  • Password: client_secret (required)
  • CommInterval: interval of regular data downloading in TimeSpan format, e.g. 01:00:00 (required)
  • CommTaskCron: optional cron expression for scheduling downloads; takes precedence over CommInterval (optional)
  • Ean: EAN of the consumption point, 18 digits (required)
  • AuthUrlTemplate: URL of the token (OAuth2) endpoint for obtaining the access token (required)

• Description
  • Universal reading of data from a relational database using custom SQL queries.
  • Supported databases (DatabaseType): PostgreSQL, MySQL.
• Notes on queries
  • VariableListSelect must return the columns:
    • Variable_Id - unique identifier of the variable
    • Variable_Name - displayed name
    • columns with the prefix MervisKey_* and MervisNonKey_* - key and supplementary metadata (e.g. unit)
  • DataRetrievalSelect uses placeholder parameters and must return the columns:
    • parameters @utcfrom, @utcto, @id (id of the variable)
    • return columns UtcTimeStamp (date and time) and DoubleValue (numeric value)
• Properties
  • ConnectionString: connection string according to the chosen database; the driver appends Pooling/Keepalive (required)
  • DatabaseType: database type: PostgreSQL or MySQL, without spaces (required)
  • CommInterval: interval of regular data downloading in TimeSpan format, e.g. 01:00:00 (required)
  • CommTaskCron: optional cron expression for scheduling downloads; takes precedence over CommInterval (optional)
  • VariableListSelect: SQL query returning the list of variables (see Notes on queries) (required)
  • DataRetrievalSelect: SQL query for downloading values with parameters @utcfrom/@utcto/@id (see Notes) (required)
  • ReadFrom: start of history (DateTimeOffset); default = first day of the current month in UTC (optional)
  • DataRetrievalDelay: delay between queries to individual variables (TimeSpan HH:MM:SS or ms) (optional)

• Description
  • Reads electricity meter registers via the DLMS/COSEM protocol over TCP.
• Properties
  • Host: IP address or hostname of the device (required)
  • Port: TCP port of the device, digits only, e.g. 4059 (required)
  • CommInterval: interval of regular data downloading in TimeSpan format, e.g. 01:00:00 (required)
  • CommTaskCron: optional cron expression for scheduling downloads; takes precedence over CommInterval (optional)
  • Password: password for authentication to the DLMS device (required)
  • ObisCode: OBIS code in the form X.X.X.X.X.X, e.g. 1.0.99.3.0.255; multiple codes separated by commas (required)
  • DeviceTimeZone: time zone of the device (Windows TZ id) used for the DLMS association (required)