Conditions

You can set conditions for when an instrument should be mutated or an event should be triggered.

Condition configuration

Here is an example of a condition on a custom instrument:

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telemetry:
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  instrumentation:
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    instruments:
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      router:
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        my.instrument:
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          value: duration
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          type: counter
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          unit: s
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          description: "my description"
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          # ...
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          # This instrument will only be mutated if the condition evaluates to true
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          condition:
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            all:
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              - any:
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                  - eq:
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                      - "val"
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                      - request_header: x-req-header
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              - eq:
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                  - "foo"
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                  - response_header: x-resp-header

exists

The exists condition is testing if selectors is present.

For example, the following condition checks the value of x-req-header exists:

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exists:
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  - request_header: x-req-header

eq

The eq condition is an equality test between selectors or values.

For example, the following condition checks the value of x-req-header is equal to val:

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eq:
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  - "val"
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  - request_header: x-req-header

You can use selectors on both sides of the equality test:

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eq:
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  - request_header: x-req-header1
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  - request_header: x-req-header2

Values may be of types string, number or boolean.

not

The not condition is a negation of the nested condition.

For example, the following condition checks the value of x-req-header is not equal to val1:

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not:
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  eq:
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    - "val1"
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    - request_header: x-req-header2

all

The all condition is a list of conditions that all must be true in order for the condition to be true.

For example, the following all condition has a list of eq conditions that check the values of x-req-header1 and x-req-header2, and both eq conditions must be true in order for the all condition to be true:

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all:
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  - eq:
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      - "val1"
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      - request_header: x-req-header1
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  - eq:
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      - "val2"
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      - request_header: x-req-header2

any

The any condition is a list of conditions of which at least one must be true for the condition to be true.

For example, the following any condition has a list of eq conditions that check the values of x-req-header1 and x-req-header2, and at least one of the eq conditions must be true in order for the all condition to be true:

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any:
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  - eq:
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      - "val2"
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      - request_header: x-req-header1
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  - eq:
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      - "val2"
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      - request_header: x-req-header2

Condition configuration reference

The available basic conditions:

You can create complex conditions by using these basic conditions as building blocks.