The HTTP interface is used to send and receive data from and to an HTTP server. The HTTP data point definition table defines all HTTP data points that are used within the project.
File location
<WorkspaceDirectory>\DataFiles\xio.HTTP.DatapointDefinitions.dat
Col# | Parameter | Description | Scope | Unit | Mandatory / default value |
---|---|---|---|---|---|
1 | Name | The name of the data point. In combination with the Path, it must be unique. | string | none | mandatory |
2 | Path | The structure that is used to represent the data point. In combination with the Name, it must be unique. | string | none | empty |
3 | Data type | The type of the data point. | BOOL, STR, BYTE, CHAR, INT8, UINT8, INT16, UINT16, INT32, UINT32, INT64, UINT64, FLOAT, DOUBLE, DATE, TIME | none | STR |
4 | Access mode | The access rights of the data point. Allowed values are R (read-only), W (write-only), RW (read and writable). | R, W, RW | none | R |
5 | Polling Url | The URL which is used to retrieve the data point value. The server polls by HTTP GET requests to this URL. If empty, polling is not available. | string | none | empty |
6 | Polling interval | The polling interval in milliseconds. | 50 – 65535 | ms | 5000 |
7 | Polling Resource | The resource that is used for polling. It has to match the name that is used in the HTTP resource definition. | Reference to HTTP resource definition | none | empty |
8 | Polling Parameters | A comma-separated list of parameters that are used to replace the placeholders within the polling resource ({0}, {1}, ...). | string | ms | empty |
9 | Update Url | The URL which is used to update the data point values. The server issues HTTP PUT, POST or GET requests to this URL. If empty, updating of the values is not possible. | string | none | empty |
10 | Update Method | The web update request method. | POST, PUT, GET | none | POST |
11 | Update Resource | The resource that is used for updating. It has to match the name that is used in the HTTP resource definition. | Reference to HTTP resource definition | none | empty |
12 | Update Parameters | A comma-separated list of parameters that are used to replace the placeholders within the update resource ({0}, {1}, ...). | string | none | empty |
13 | Persistent | If enabled, the last known data point value is restored after server start up. | true/false | none | false |
14 | Synchronize | If enabled, the value is synchronized with the backup server if used. | true/false | none | true |
15 | Authentication User | Username for Basic or Digest HTTP authentication if required by the HTTP server. If empty, no HTTP authentication is used. | string | none | empty |
16 | Authentication Password | Password for Basic or Digest HTTP authentication if required by the HTTP server. If empty, no HTTP authentication is used. | string | none | empty |
17 | Additional HTTP Headers | A list of additional HTTP headers which is included in each HTTP request, e.g. for authentication purposes. Additional headers must have the following form: "<key1>: <value1>\r\n<key2>: <value2>\r\n<key3>: <value3>..." | string | none | empty |
18 | Authentication Method | The authentication method (Basic or Digest) if required by the HTTP server. | Basic, Digest | none | Basic |