/// <summary>
/// Finds an appropriate candidate for a `page size`/`max results` request field.
/// That is a field that is named "page_size" or "max_results" and has a non-repeated Int32 type, if any.
/// If no such field exists, then simply a field that is named "page_size" or "max_results".
/// </summary>
private static FieldDescriptor FindPageSizeCandidate(MessageDescriptor input)
{
// Has the int32 page_size or int32 max_results field which defines the maximum number of paginated resources to return in the response
var pageSizeCandidate = input.FindFieldByName("page_size");
var maxResultsCandidate = input.FindFieldByName("max_results");
// If both candidates are invalid, this might return a non-null 'invalid' candidate.
// An exception should be thrown, but only if method has _all_ candidates, which we will only know later.
return(IsValidPageSizeCandidate(pageSizeCandidate) ? pageSizeCandidate
: IsValidPageSizeCandidate(maxResultsCandidate) ? maxResultsCandidate
: pageSizeCandidate ?? maxResultsCandidate);
}
/// <summary>
/// Retrieves the descriptor for the field with the given name.
/// </summary>
/// <param name="name">Name of the field to retrieve the descriptor for</param>
/// <returns>The descriptor for the given field</returns>
/// <exception cref="KeyNotFoundException">The message descriptor does not contain a field
/// with the given name</exception>
public FieldDescriptor this[string name]
{
get
{
var fieldDescriptor = messageDescriptor.FindFieldByName(name);
if (fieldDescriptor == null)
{
throw new KeyNotFoundException("No such field name");
}
return(fieldDescriptor);
}
}