Adding upstream version 1.34.4.

Signed-off-by: Daniel Baumann <daniel@debian.org>

plugins/processors/scale/README.md

@@ -0,0 +1,83 @@
+# Scale Processor Plugin
+
+The scale processor filters for a set of fields,
+and scales the respective values from an input range into
+the given output range according to this formula:
+
+```math
+\text{result}=(\text{value}-\text{input\_minimum})\cdot\frac{(\text{output\_maximum}-\text{output\_minimum})}
+{(\text{input\_maximum}-\text{input\_minimum})} +
+\text{output\_minimum}
+```
+
+Alternatively, you can apply a factor and offset to the input according to
+this formula
+
+```math
+\text{result}=\text{factor} \cdot \text{value} + \text{offset}
+```
+
+Input fields are converted to floating point values if possible. Otherwise,
+fields that cannot be converted are ignored and keep their original value.
+
+**Please note:** Neither the input nor the output values are clipped to their
+                 respective ranges!
+
+## Global configuration options <!-- @/docs/includes/plugin_config.md -->
+
+In addition to the plugin-specific configuration settings, plugins support
+additional global and plugin configuration settings. These settings are used to
+modify metrics, tags, and field or create aliases and configure ordering, etc.
+See the [CONFIGURATION.md][CONFIGURATION.md] for more details.
+
+[CONFIGURATION.md]: ../../../docs/CONFIGURATION.md#plugins
+
+## Configuration
+
+```toml @sample.conf
+# Scale values with a predefined range to a different output range.
+[[processors.scale]]
+    ## It is possible to define multiple different scaling that can be applied
+    ## do different sets of fields. Each scaling expects the following
+    ## arguments:
+    ##   - input_minimum: Minimum expected input value
+    ##   - input_maximum: Maximum expected input value
+    ##   - output_minimum: Minimum desired output value
+    ##   - output_maximum: Maximum desired output value
+    ## alternatively you can specify a scaling with factor and offset
+    ##   - factor: factor to scale the input value with
+    ##   - offset: additive offset for value after scaling
+    ##   - fields: a list of field names (or filters) to apply this scaling to
+
+    ## Example: Scaling with minimum and maximum values
+    # [[processors.scale.scaling]]
+    #    input_minimum = 0.0
+    #    input_maximum = 1.0
+    #    output_minimum = 0.0
+    #    output_maximum = 100.0
+    #    fields = ["temperature1", "temperature2"]
+
+    ## Example: Scaling with factor and offset
+    # [[processors.scale.scaling]]
+    #    factor = 10.0
+    #    offset = -5.0
+    #    fields = ["voltage*"]
+```
+
+## Example
+
+The example below uses these scaling values:
+
+```toml
+[[processors.scale.scaling]]
+    input_minimum = 0.0
+    input_maximum = 50.0
+    output_minimum = 50.0
+    output_maximum = 100.0
+    fields = ["cpu"]
+```
+
+```diff
+- temperature, cpu=25
++ temperature, cpu=75.0
+```