FTP

The FTP Connector connects to an external FTP server, reads data from files at configured paths, and pushes it to ThingsBoard. It can also write data back to FTP files in response to attribute updates or RPC commands.

To enable this connector, add it to the connectors list in tb_gateway.json — see the General Configuration reference.

Connector configuration: ftp.json

The connector reads its settings from a JSON file. Below is a full example:

{
  "host": "0.0.0.0",
  "port": 21,
  "TLSSupport": false,
  "security": {
    "type": "basic",
    "username": "admin",
    "password": "admin"
  },
  "paths": [
    {
      "devicePatternName": "asd",
      "devicePatternType": "Device",
      "delimiter": ",",
      "path": "fol/*_hello*.txt",
      "readMode": "FULL",
      "maxFileSize": 5,
      "pollPeriod": 5,
      "txtFileDataView": "SLICED",
      "withSortingFiles": true,
      "attributes": [
        { "key": "temp", "value": "[1:]"  },
        { "key": "tmp",  "value": "[0:1]" }
      ],
      "timeseries": [
        { "type": "int", "key": "[0:1]", "value": "[0:1]" },
        { "type": "int", "key": "temp",  "value": "[1:]"  }
      ]
    }
  ],
  "attributeUpdates": [
    {
      "path": "fol/hello.json",
      "deviceNameFilter": ".*",
      "writingMode": "WRITE",
      "valueExpression": "{'${attributeKey}':'${attributeValue}'}"
    }
  ],
  "serverSideRpc": [
    {
      "deviceNameFilter": ".*",
      "methodFilter": "read",
      "valueExpression": "${params}"
    },
    {
      "deviceNameFilter": ".*",
      "methodFilter": "write",
      "valueExpression": "${params}"
    }
  ]
}

Section “General”

Top-level connection parameters for the FTP server.

Parameter	Default	Description
`host`	`localhost`	FTP server hostname or IP address
`port`	`21`	FTP server port
`TLSSupport`	`true`	Verify that TLS is available on the server

Subsection “security”

Configures how the connector authenticates with the FTP server.

Basic
Anonymous

Username and password authentication.

Parameter	Default	Description
`type`	`basic`	Authorization type
`username`		Username
`password`		Password

"security": {
  "type": "basic",
  "username": "admin",
  "password": "admin"
}

Anonymous access — useful for public FTP servers or during testing.

Parameter	Default	Description
`type`	`anonymous`	Authorization type

"security": {
  "type": "anonymous"
}

Section “paths”

An array of path configurations. Each entry tells the connector which files to read, how often, and how to map the file contents to ThingsBoard device attributes and telemetry.

Path parameters

Parameter	Description
`path`	Path to the file(s) on the FTP server. Supports `*` wildcards
`devicePatternName`	Expression to build the ThingsBoard device name
`devicePatternType`	Expression to determine the device type
`delimiter`	Character used to split values within a file line
`readMode`	`FULL` — read the entire file each poll; `PARTIAL` — read only new lines since the last poll
`maxFileSize`	Maximum file size in MB to read; larger files are skipped
`pollPeriod`	How often to poll the path, in seconds
`txtFileDataView`	`TABLE` — first line is a header; `SLICED` — no header, values extracted by index. Only applies to `.txt` files
`withSortingFiles`	Whether to sort matched files before processing
`attributes`	Mappings from file values to ThingsBoard device attributes
`timeseries`	Mappings from file values to ThingsBoard time-series telemetry

Path wildcard examples — for files in an FTP directory tree:

Path	Matches
`data/log.txt`	One specific file
`data/*/log.txt`	`log.txt` in any immediate subdirectory of `data/`
`data/*/_log.txt`	Files ending in `_log.txt` in any immediate subdirectory of `data/`
`data/.`	All files with supported extensions in `data/`

Path examples by file format

The first line is treated as a header. Key names and value expressions reference column header names.

"paths": [
  {
    "devicePatternName": "${temp}",
    "devicePatternType": "Device",
    "delimiter": ",",
    "path": "fol/*.*",
    "readMode": "FULL",
    "maxFileSize": 5,
    "pollPeriod": 60,
    "txtFileDataView": "TABLE",
    "withSortingFiles": true,
    "attributes": [
      { "type": "int", "key": "key", "value": "${temp}" }
    ],
    "timeseries": [
      { "type": "int", "key": "${hum}",  "value": "${temp}" },
      { "type": "int", "key": "temp",    "value": "${hum}"  }
    ]
  }
]

Expected file structure:

temp,hum
1,2
23,34

No header. Values are extracted by byte/character slice positions ([from:to]).

"paths": [
  {
    "devicePatternName": "DeviceName",
    "devicePatternType": "[0:1]",
    "delimiter": ",",
    "path": "fol/table.txt",
    "readMode": "FULL",
    "maxFileSize": 5,
    "pollPeriod": 60,
    "txtFileDataView": "SLICED",
    "withSortingFiles": true,
    "attributes": [
      { "key": "temp", "value": "[1:]"  },
      { "key": "tmp",  "value": "[0:1]" }
    ],
    "timeseries": [
      { "type": "int", "key": "[0:1]", "value": "[0:1]" },
      { "type": "int", "key": "temp",  "value": "[1:]"  }
    ]
  }
]

Expected file structure:

1,2
23,34

Key and value expressions reference JSON field names using ${fieldName} syntax.

"paths": [
  {
    "devicePatternName": "${temp}",
    "devicePatternType": "Device",
    "delimiter": ",",
    "path": "fol/*.json",
    "readMode": "FULL",
    "maxFileSize": 5,
    "pollPeriod": 60,
    "withSortingFiles": true,
    "attributes": [
      { "type": "int", "key": "key", "value": "${temp}" }
    ],
    "timeseries": [
      { "type": "int", "key": "key",  "value": "${temp}" },
      { "type": "int", "key": "temp", "value": "${tmp}"  }
    ]
  }
]

Attributes, telemetry, and a combined string value from the same JSON file.

"paths": [
  {
    "devicePatternName": "${temp}",
    "devicePatternType": "Device",
    "delimiter": ",",
    "path": "fol/*.json",
    "readMode": "FULL",
    "maxFileSize": 5,
    "pollPeriod": 60,
    "withSortingFiles": true,
    "attributes": [],
    "timeseries": [
      { "type": "int",    "key": "hum",     "value": "${hum}"          },
      { "type": "int",    "key": "temp",    "value": "${tmp}"          },
      { "type": "string", "key": "combine", "value": "${tmp}::${hum}"  }
    ]
  }
]

Subsection “converter” (optional)

Use a custom converter when the file format is not natively supported (e.g. CSV without headers, or CSV with fixed column positions).

{
  "converter": {
    "type": "custom",
    "extension": "CustomFTPtUplinkConverter",
    "extension-config": {
      "devicePatternName": 0,
      "devicePatternType": 1,
      "attributes": [
        { "key": "meterAddress",  "column": 0, "type": "string" }
      ],
      "timeseries": [
        { "key": "meterReading",  "column": 2, "type": "double" },
        { "key": "batteryAlert",  "column": 3, "type": "int"    }
      ]
    }
  }
}

Parameter	Description
`type`	Must be `custom`
`extension`	Name of the Python class implementing the custom converter
`extension-config.devicePatternName`	Zero-based column index for the device name
`extension-config.devicePatternType`	Zero-based column index (or literal) for the device type
`extension-config.attributes[].key`	ThingsBoard attribute key name
`extension-config.attributes[].column`	Zero-based column index to read the attribute value from
`extension-config.attributes[].type`	Value type: `string`, `int`, or `double`
`extension-config.timeseries[].key`	ThingsBoard telemetry key name
`extension-config.timeseries[].column`	Zero-based column index to read the telemetry value from
`extension-config.timeseries[].type`	Value type: `string`, `int`, or `double`

Section “attributeUpdates”

Optional. Writes ThingsBoard shared attribute updates to files on the FTP server.

Parameter	Default	Description
`path`		Path to the target file on the FTP server. Supports `${attributeKey}` and `${attributeValue}` expressions
`deviceNameFilter`	`.*`	Regex filter to match device names
`writingMode`		`OVERRIDE` — overwrite the file; `WRITE` — append to the end of the file
`valueExpression`		Expression used to build the content written to the file

"attributeUpdates": [
  {
    "path": "fol/${attributeKey}/${attributeValue}.txt",
    "deviceNameFilter": ".*",
    "writingMode": "OVERRIDE",
    "valueExpression": ",,,,${attributeKey},,,${attributeValue}"
  }
]

Section “serverSideRpc”

Optional. Maps ThingsBoard RPC method calls to read or write operations on FTP server files.

Parameter	Default	Description
`deviceNameFilter`	`.*`	Regex filter to match device names
`methodFilter`		`read` — read from a file; `write` — write to a file
`valueExpression`		Expression used to build the content to write (ignored for `read` operations)

"serverSideRpc": [
  {
    "deviceNameFilter": ".*",
    "methodFilter": "read",
    "valueExpression": "${params}"
  },
  {
    "deviceNameFilter": ".*",
    "methodFilter": "write",
    "valueExpression": "${params}"
  }
]

Read example

Suppose you want to read data from the file on connected FTP server. Go to enabled FTP connector RPC page and fill in fields with the following configuration and click on “Send” button. After that, response will be shown in the “Response” field:

RPC terminal with read request parameters filled in

Write example

Suppose you want to write some data to the file on connected FTP server. Go to enabled FTP connector RPC page and fill in fields with the following configuration and click on “Send” button. After that, response will be shown in the “Response” field:

RPC terminal with write request parameters filled in

RPC response confirming the write succeeded

RPC terminal with a read request to verify the written data

RPC response showing the previously written data

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