Gotchas.md

Gotchas

This is a compilation of gotchas, mostly related to unexpected behaviors and conditions in the FileMaker Data API itself, or the relationship of those with this library.

Duplicated (same name) portals

In FileMaker a single layout can hold two or more portals with the same name. In that situation the Data API will include each portal in the response JSON without regard for the duplication, resulting in an invalid JSON with two identical keys at the same level. E.g.:

{
  "response": {
    "data": [{
      "fieldData": {
        …
      },
      "portalData": {
        "MyPortal": [{
          …
        }],
        "MyPortal": [{
          …
        }]
      },
      "portalDataInfo": [{
        "portalObjectName": "MyPortal",
        "database": "…",
        "table": "…",
        "foundCount": 3,
        "returnedCount": 3
      },
      {
        "portalObjectName": "MyPortal",
        "database": "…",
        "table": "…",
        "foundCount": 3,
        "returnedCount": 3
      }]
    }]
  },
  …
}

Because fmrest-ruby uses standard JSON parsers that (correctly) don't account for this kind of key duplication, in situations like this only one of the duplicated portals will be ingested, with no way of controlling which one will be.

The solution to this is to give each portal a unique name within the FileMaker layout.