upload/koji: don't depend on upload target results data structures

Modify the Koji image extra metadata to not depend on the upload target
data structures for upload results. The target results are supposed to
be specific to the uploader implementation, which will eventually
change. Moreover, the definition is internal to osbuild-composer, so
this would create a problem once the Koji upload implementation is moved
to osbuild/images.

The Koji upload implementation does not really care about the exact
structure of the upload results. It is just a list of JSON objects.

Signed-off-by: Tomáš Hozza <thozza@redhat.com>

cmd/osbuild-worker/jobimpl-koji-finalize.go

@@ -208,8 +208,8 @@ func (impl *KojiFinalizeJobImpl) Run(job worker.Job) error {
 		// If there are any non-Koji target results in the build,
 		// add them to the image output extra metadata.
 		nonKojiTargetResults := buildResult.TargetResultsFilterByName([]target.TargetName{target.TargetNameKoji})
-		if len(nonKojiTargetResults) > 0 {
-			imgOutputExtraInfo.UploadTargetResults = nonKojiTargetResults
+		for _, result := range nonKojiTargetResults {
+			imgOutputExtraInfo.UploadTargetResults = append(imgOutputExtraInfo.UploadTargetResults, result)
 		}
 
 		imgOutputsExtraInfo[imageFilename] = imgOutputExtraInfo

internal/upload/koji/metadata.go

@@ -98,8 +98,9 @@ type ImageExtraInfo struct {
 	// Version of the osbuild binary used by the worker to build the image
 	OSBuildVersion string `json:"osbuild_version,omitempty"`
 	// Results from any upload targets associated with the image
-	// except for the Koji target.
-	UploadTargetResults []*target.TargetResult `json:"upload_target_results,omitempty"`
+	// The structure of the data does not need to be known by the consumer,
+	// it is just a list of JSON objects.
+	UploadTargetResults []interface{} `json:"upload_target_results,omitempty"`
 }
 
 func (ImageExtraInfo) isImageOutputTypeMD() {}