Conditional Execution
When a processor is attached to a connector or to a pipeline, we may still
want to specify conditions for its execution. To do this, we can add a condition
key to the processor definition in the Pipeline Configuration File, or using
the HTTP API including this parameter in the POST request.
The condition
key follows the Go templates format, allowing the use of
any function provided by sprig.
If the expression evaluates to true, the processor will be executed; otherwise, the record will continue to flow in the pipeline without being processed by this processor.
Conduit will parse the output of the go template using
strconv.ParseBool
which means that 1
,
t
, T
, TRUE
, true
and True
will all evaluate to true
, while 0
, f
,
F
, FALSE
, false
, False
will be evaluated to false
. If an expression can't
be evaluated as a boolean, the processor will return an error.
Example of a condition
Here's an example of a simple condition. In this case, records will be processed
by the json.decode
builtin processsor when
he OpenCDC Metadata contains a key named
key
which value is equal to expected-value
.
version: 2.2
pipelines:
- id: example-pipeline
connectors:
# define source and destination connectors
# ...
processors:
- id: extract-name
plugin: json.decode
settings:
field: .Payload.After.name
condition: `{{ eq .Metadata.key "expected-value" }}`