/// <summary>
/// Parse the query and return the search parameters.
/// </summary>
/// <exception cref="InvalidOperationException">Thrown when something goes wrong in the operation.</exception>
/// <param name="query">Query parameters.</param>
/// <returns>Search parameters.</returns>
public SearchParameter ParseQuery(IQueryCollection query)
{
var result = new SearchParameter();
if (query == null)
{
return(result);
}
foreach (var key in query.Keys)
{
TrySetEnum((r) => result.Attributes = r.Select(a => GetFilter(a)), key, Common.Constants.SearchParameterNames.Attributes, query);
TrySetEnum((r) => result.ExcludedAttributes = r.Select(a => GetFilter(a)), key, Common.Constants.SearchParameterNames.ExcludedAttributes, query);
TrySetStr((r) => result.Filter = GetFilter(r), key, Common.Constants.SearchParameterNames.Filter, query);
TrySetStr((r) => result.SortBy = GetFilter(r), key, Common.Constants.SearchParameterNames.SortBy, query);
TrySetStr((r) => result.SortOrder = GetSortOrder(r), key, Common.Constants.SearchParameterNames.SortOrder, query);
TrySetInt((r) => result.StartIndex = r <= 0 ? result.StartIndex : r, key, Common.Constants.SearchParameterNames.StartIndex, query);
TrySetInt((r) => result.Count = r <= 0 ? result.Count : r, key, Common.Constants.SearchParameterNames.Count, query);
}
return(result);
}
/// <summary>
/// Filter the representations and return the result.
/// </summary>
/// <exception cref="ArgumentNullException">Thrown when representations are null.</exception>
/// <param name="representationAttributes">Representations to filter.</param>
/// <param name="searchParameter">Search parameters.</param>
/// <returns>Filtered response</returns>
public FilterResult Filter(
IEnumerable <Representation> representations,
SearchParameter searchParameter)
{
if (representations == null)
{
throw new ArgumentNullException(nameof(representations));
}
if (searchParameter == null)
{
throw new ArgumentNullException(nameof(searchParameter));
}
IEnumerable <string> commonAttrs = new[]
{
Common.Constants.MetaResponseNames.ResourceType,
Common.Constants.MetaResponseNames.Created,
Common.Constants.MetaResponseNames.LastModified,
Common.Constants.MetaResponseNames.Version,
Common.Constants.MetaResponseNames.Location
};
var result = new JArray();
// 1. Sort the representations.
if (searchParameter.SortBy != null)
{
var comparer = new RepresentationComparer(searchParameter.SortBy);
if (searchParameter.SortOrder == SortOrders.Ascending)
{
representations = representations.OrderBy(repr => repr, comparer);
}
else
{
representations = representations.OrderByDescending(repr => repr, comparer);
}
}
// 2. Filter the representations.
foreach (var representation in representations)
{
// 1. Apply filter on the values.
if (searchParameter.Filter != null)
{
if (!searchParameter.Filter.Evaluate(representation).Any())
{
continue;
}
}
// 2. Exclude & include certains attributes.
IEnumerable <RepresentationAttribute> attributes = null;
if (searchParameter.ExcludedAttributes != null && searchParameter.ExcludedAttributes.Any())
{
foreach (var excludedAttrFilter in searchParameter.ExcludedAttributes)
{
var excludedAttrs = excludedAttrFilter.Evaluate(representation);
if (excludedAttrs == null)
{
continue;
}
foreach (var excludedAttr in excludedAttrs)
{
var excludedParent = excludedAttr.Parent as ComplexRepresentationAttribute;
if (excludedParent == null)
{
continue;
}
excludedParent.Values = excludedParent.Values.Where(v => !excludedAttrs.Contains(v));
}
}
}
if (searchParameter.Attributes != null && searchParameter.Attributes.Any())
{
attributes = new List <RepresentationAttribute>();
foreach (var attrFilter in searchParameter.Attributes)
{
attributes = attributes.Concat(attrFilter.Evaluate(representation));
}
}
else
{
attributes = representation.Attributes;
}
if (attributes == null || !attributes.Any())
{
continue;
}
// 3. Add all attributes
var obj = new JObject();
foreach (JProperty token in attributes.Select(a => (JProperty)GetToken(a, a.SchemaAttribute)))
{
var value = obj[token.Name];
if (value != null)
{
var arr = value as JArray;
if (arr != null)
{
arr.Add(token.Value);
}
else
{
obj[token.Name] = new JArray(value, token.Value);
}
}
else
{
obj.Add(token);
}
}
result.Add(obj);
}
var filterResult = new FilterResult();
if (result.Count() > searchParameter.Count)
{
filterResult.StartIndex = searchParameter.StartIndex;
filterResult.ItemsPerPage = searchParameter.Count;
filterResult.Values = result.Skip(searchParameter.StartIndex - 1).Take(searchParameter.Count);
}
else
{
filterResult.Values = result;
}
filterResult.TotalNumbers = result.Count();
// 3. Paginate the representations.
return(filterResult);
}
