func getDownloaders()

in internal/files/files.go [96:138]
31 lines of code
11 McCabe index (conditional complexity)

func getDownloaders(fileURL string, managedIdentity *handlersettings.RunCommandManagedIdentity, msiDownloader download.MsiDownloader) ([]download.Downloader, error) {

	if fileURL == "" {
		return nil, fmt.Errorf("fileURL is empty")
	}

	if download.IsAzureStorageBlobUri(fileURL) {
		// if managed identity was specified in the configuration, try to use it to download the files
		var msiProvider download.MsiProvider

		switch {
		case managedIdentity == nil || (managedIdentity.ClientId == "" && managedIdentity.ObjectId == ""):
			// get msi Provider for blob url implicitly (uses system managed identity)
			msiProvider = msiDownloader.GetMsiProvider(fileURL)

		case managedIdentity.ClientId != "" && managedIdentity.ObjectId == "":
			// uses user-managed identity
			msiProvider = msiDownloader.GetMsiProviderByClientId(fileURL, managedIdentity.ClientId)
		case managedIdentity.ClientId == "" && managedIdentity.ObjectId != "":
			// uses user-managed identity
			msiProvider = msiDownloader.GetMsiProviderByObjectId(fileURL, managedIdentity.ObjectId)
		default:
			return nil, fmt.Errorf("use either ClientId or ObjectId for managed identity. Not both")
		}

		_, msiError := msiProvider()
		if msiError == nil {
			return []download.Downloader{
				//Try downloading with MSI token first, if that fails attempt public download
				download.NewBlobWithMsiDownload(fileURL, msiProvider),
				download.NewURLDownload(fileURL), // Try downloading the Azure storage blob as public URI
			}, nil
		} else {
			return []download.Downloader{
				// Try downloading the Azure storage blob as public URI
				download.NewURLDownload(fileURL),
			}, nil
		}
	} else {
		// Public URI - do not use MSI downloader if the uri is not azure storage blob
		return []download.Downloader{download.NewURLDownload(fileURL)}, nil
	}
}