Supported pipeline types: metrics
The filter processor can be configured to include or exclude metrics based on metric name in the case of the 'strict' or 'regexp' match types, or based on other metric attributes in the case of the 'expr' match type. Please refer to config.go for the config spec.
It takes a pipeline type, of which only metrics
is supported, followed by an
action:
include
: Any names NOT matching filters are excluded from remainder of pipelineexclude
: Any names matching filters are excluded from remainder of pipeline
For the actions the following parameters are required:
match_type
: strict|regexp|exprmetric_names
: (only for amatch_type
of 'strict' or 'regexp') list of strings or re2 regex patternsexpressions
: (only for amatch_type
of 'expr') list of expr expressions (see "Using an 'expr' match_type" below)resource_attributes
: ResourceAttributes defines a list of possible resource attributes to match metrics against. A match occurs if any resource attribute matches at least one expression in this given list.
More details can found at include/exclude metrics.
Examples:
processors:
filter/1:
metrics:
include:
match_type: regexp
metric_names:
- prefix/.*
- prefix_.*
resource_attributes:
- Key: container.name
Value: app_container_1
exclude:
match_type: strict
metric_names:
- hello_world
- hello/world
Refer to the config files in testdata for detailed examples on using the processor.
In addition to matching metric names with the 'strict' or 'regexp' match types, the filter processor
supports matching entire Metric
s using the expr expression engine.
The 'expr' filter evaluates the supplied boolean expressions per datapoint on a metric, and returns a result for the entire metric. If any datapoint evaluates to true then the entire metric evaluates to true, otherwise false.
Made available to the expression environment are the following:
MetricName
a variable containing the current Metric's nameLabel(name)
a function that takes a label name string as an argument and returns a string: the value of a label with that name if one exists, or ""HasLabel(name)
a function that takes a label name string as an argument and returns a boolean: true if the datapoint has a label with that name, false otherwise
Example:
processors:
filter/1:
metrics:
exclude:
match_type: expr
expressions:
- MetricName == "my.metric" && Label("my_label") == "abc123"
The above config will filter out any Metric that both has the name "my.metric" and has at least one datapoint with a label of 'my_label="abc123"'.
As with "strict" and "regexp", multiple "expr" expressions
are allowed.
For example, the following two filters have the same effect: they filter out metrics named "system.cpu.time" and "system.disk.io".
processors:
filter/expr:
metrics:
exclude:
match_type: expr
expressions:
- MetricName == "system.cpu.time"
- MetricName == "system.disk.io"
filter/strict:
metrics:
exclude:
match_type: strict
metric_names:
- system.cpu.time
- system.disk.io
The expressions are effectively ORed per datapoint. So for the above 'expr' configuration, given a datapoint, if its parent Metric's name is "system.cpu.time" or "system.disk.io" then there's a match. The conditions are tested against all the datapoints in a Metric until there's a match, in which case the entire Metric is considered a match, and in the above example the Metric will be excluded. If after testing all the datapoints in a Metric against all the expressions there isn't a match, the entire Metric is considered to be not matching.
In addition to the names, metrics can be filtered using resource attributes. resource_attributes
takes a list of resource attributes to filter metrics against.
Following example will include only the metrics coming from app_container_1
(the value for container.name
resource attribute is app_container_1
).
processors:
filter:
metrics:
include:
match_type: strict
metric_names:
- hello_world
- hello/world
resource_attributes:
- Key: container.name
Value: app_container_1
Following example will exclude all the metrics coming from app_container_1
(the value for container.name
resource attribute is app_container_1
).
processors:
filter:
metrics:
exclude:
match_type: strict
metric_names:
- hello_world
- hello/world
resource_attributes:
- Key: container.name
Value: app_container_1
We can also use regexp
to filter metrics using resource attributes. Following example will include only the metrics coming from app_container_1
or app_container_2
(the value for container.name
resource attribute is either app_container_1
or app_container_2
).
processors:
filter:
metrics:
exclude:
match_type: regexp
metric_names:
- hello_world
- hello/world
resource_attributes:
- Key: container.name
Value: (app_container_1|app_container_1)