As we mentioned in the Processors section, the optional if parameter is designed to let users define conditions for executing the pipeline processor. Let's demo a simple case with an example. The rating field of the documents in the index of cf_etf is a single space string when no rating is given for ETF in the original source. We can use the remove processor to remove the rating field in such a condition before the indexing operation, as shown in the following code block:
"pipeline": {
"description":"remove the rating field if the rating is equal to a single space string",
"processors":[{
"remove": {
"field": "rating",
"if": "ctx.rating == ' '"
}
}]
}
You will recall the dividend information...