multifile

Multifile Input Plugin

The multifile input plugin allows Telegraf to combine data from multiple files into a single metric, creating one field or tag per file. This is often useful creating custom metrics from the /sys or /proc filesystems.

Note: If you wish to parse metrics from a single file formatted in one of the supported input data formats, you should use the file input plugin instead.

Configuration

[[inputs.multifile]]
  ## Base directory where telegraf will look for files.
  ## Omit this option to use absolute paths.
  base_dir = "/sys/bus/i2c/devices/1-0076/iio:device0"

  ## If true discard all data when a single file can't be read.
  ## Else, Telegraf omits the field generated from this file.
  # fail_early = true

  ## Files to parse each interval.
  [[inputs.multifile.file]]
    file = "in_pressure_input"
    dest = "pressure"
    conversion = "float"
  [[inputs.multifile.file]]
    file = "in_temp_input"
    dest = "temperature"
    conversion = "float(3)"
  [[inputs.multifile.file]]
    file = "in_humidityrelative_input"
    dest = "humidityrelative"
    conversion = "float(3)"

Each file table can contain the following options:

• file: Path of the file to be parsed, relative to the base_dir.
• dest: Name of the field/tag key, defaults to $(basename file).
• conversion: Data format used to parse the file contents:
  • float(X): Converts the input value into a float and divides by the Xth power of 10. Effectively just moves the decimal left X places. For example a value of 123 with float(2) will result in 1.23.
  • float: Converts the value into a float with no adjustment. Same as float(0).
  • int: Converts the value into an integer.
  • string, "": No conversion.
  • bool: Converts the value into a boolean.
  • tag: File content is used as a tag.

Example Output

This example shows a BME280 connected to a Raspberry Pi, using the sample config.

multifile pressure=101.343285156,temperature=20.4,humidityrelative=48.9 1547202076000000000

To reproduce this, connect a BMP280 to the board's GPIO pins and register the BME280 device driver

cd /sys/bus/i2c/devices/i2c-1
echo bme280 0x76 > new_device

The kernel driver provides the following files in /sys/bus/i2c/devices/1-0076/iio:device0:

• in_humidityrelative_input: 48900
• in_pressure_input: 101.343285156
• in_temp_input: 20400