> For the complete documentation index, see [llms.txt](https://docs.dnscontrol.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.dnscontrol.org/developer-info/provider-conversion-tests.md).

# Provider conversion tests

* [Adding provider conversion golden tests](#adding-provider-conversion-golden-tests)
  * [Instrument the provider](#instrument-the-provider)
  * [Add replay tests](#add-replay-tests)

`pkg/providergolden` records and replays the exact conversion calls exercised by integration tests. See [Provider conversion golden files](/developer-info/goldenfiles.md) for the recording workflow and file formats.

## Instrument the provider

Add a `providers.ConversionObserver` field to the provider and implement `SetConversionObserver`. Around each conversion boundary, pass the same input to `Begin` before conversion and `End` after conversion, together with the result and error:

```go
before := providers.BeginToRC(p.observer, "toRc", native)
records, err := toRc(dc, native)
providers.EndToRC(p.observer, "toRc", before, native, records, err)
```

For the other direction:

```go
input := models.Records{record}
before := providers.BeginToNative(p.observer, "toReq", input)
request, err := toReq(record)
providers.EndToNative(p.observer, "toReq", before, input, request, err)
```

Observe the conversion at every call site used by integration tests. Use the conversion function's exact name as the observer name.

## Add replay tests

Adapters receive the domain from `test_data/meta.json`; no environment variable is needed.

```go
func TestToRcGolden(t *testing.T) {
    providergolden.CheckToRC(t, "toRc",
        func(dc *models.DomainConfig, native domainRecord) (models.Records, error) {
            rc, err := toRc(dc, &native)
            return models.Records{rc}, err
        })
}

func TestToReqGolden(t *testing.T) {
    providergolden.CheckToNative(t, "toReq",
        func(_ *models.DomainConfig, records models.Records) (requestParams, error) {
            return toReq(records[0])
        })
}
```

`CheckToNative` passes all records sharing an index in one call, which supports record-set conversions. `CheckRoundTrip` can additionally verify providers whose two conversions are compatible.

An unrecorded function is skipped. Once a passing integration run is available, record it with `-record`, inspect the new files, and run the provider package normally to verify replay.