SearchKit - Allow functions in the WHERE clause

[colemanw]

Overview

Advanced feature for SearchKit allows SQL functions in the WHERE clause. They are selected in the same way as the "Field Transformations" tab.

[civibot]

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[pfigel]

This looks great, thanks @colemanw! I've done a quick round of testing and discovered that the generated API4 request appears to be missing the isExpression bool in where clauses with functions. The generated request for Year Only Birth Date = 1991 looks like this:

{
  "version": 4,
  "select": [
    "id",
    "display_name"
  ],
  "orderBy": [],
  "where": [
    [
      "YEAR(birth_date)",
      "=",
      1991
    ]
  ],
  "groupBy": [],
  "join": [],
  "having": []
}

It should look like this:

{
  "version": 4,
  "select": [
    "id",
    "display_name"
  ],
  "orderBy": [],
  "where": [
    [
      "YEAR(birth_date)",
      "=",
      1991,
      true
    ]
  ],
  "groupBy": [],
  "join": [],
  "having": []
}

[colemanw]

@pfigel are you sure about that? My understanding is that the 4th boolean argument controls how the 3rd argument is interpreted, not the first. I think the first argument is always parsed as an expression, because a field name is expected.
This PR is limited to the 1st argument of a where clause. The 3rd is still assumed to be a scalar value.

[pfigel]

@colemanw I'm fairly certain, yes. where without the bool hits this if, which expects a field, whereas the bool variant goes here and accepts expressions. The request without isExpression=true fails with Invalid field 'YEAR(birth_date)'.

[colemanw]

Thanks @pfigel - you're right, but IMO that was too restrictive. The first arg of the WHERE clause is always interpreted as an expression, so functions ought to be allowed regardless of the 4th param.

I've loosened the restriction and added a unit test to ensure it works correctly in both modes.

[eileenmcnaughton]

Not sure my searches are super useful but they worked....