public QueryParserResult Parse <T>(Query query)
{
var result = new QueryParserResult {
Ok = true
};
List <PropertyInfo> properties = typeof(T).GetProperties().ToList();
result.Projections = GetProjections(properties, query?.Fields);
var selectionPredicate = GetSelectionPredicate(properties, query.Filters);
result.Predicate = selectionPredicate.predicate;
result.Parameters = selectionPredicate.parameters;
result.Sort = GetOrderByQuery(properties, query.Sort);
result.Skip = query.Skip;
result.Take = query.Take;
return(result);
}
public QueryParserResult Parse <T>(IDictionary <string, string> queryParams)
{
var result = new QueryParserResult
{
Ok = true,
QueryParameters = new QueryParameters()
};
if (queryParams.Count == 0)
{
return(result);
}
List <PropertyInfo> properties = typeof(T).GetProperties().ToList();
StringBuilder predicate = new StringBuilder("WHERE 1 = 1");
StringBuilder orderBy = new StringBuilder("ORDER BY ");
var parameters = new DPR.DynamicParameters();
foreach (var kvp in queryParams)
{
PropertyInfo propertyInfo;
if (kvp.Key.Equals("skip", StringComparison.OrdinalIgnoreCase) && !string.IsNullOrWhiteSpace(kvp.Value))
{
int skip;
if (!int.TryParse(kvp.Value, out skip))
{
result.Ok = false;
result.Error = String.Format("Failed to parse skip value '{0}' as int", kvp.Value);
return(result);
}
result.QueryParameters.Skip = skip;
}
else if (kvp.Key.Equals("take", StringComparison.OrdinalIgnoreCase) && !string.IsNullOrWhiteSpace(kvp.Value))
{
int take;
if (!int.TryParse(kvp.Value, out take))
{
result.Ok = false;
result.Error = String.Format("Failed to parse take value '{0}' as int", kvp.Value);
return(result);
}
result.QueryParameters.Take = take;
}
else if (kvp.Key.Equals("sort", StringComparison.OrdinalIgnoreCase) && !string.IsNullOrWhiteSpace(kvp.Value))
{
string[] sortParams = kvp.Value.Split(new char[] { ',' }, StringSplitOptions.RemoveEmptyEntries);
foreach (var sortParam in sortParams)
{
bool desc = sortParam[0] == '-';
var sortParamName = sortParam.TrimStart(new char[] { '-' });
if ((propertyInfo = properties.Where(p => p.Name.Equals(sortParamName, StringComparison.OrdinalIgnoreCase)).FirstOrDefault()) != null)
{
orderBy.AppendFormat("[{0}]", propertyInfo.Name);
if (desc)
{
orderBy.Append(" DESC");
}
orderBy.Append(",");
}
}
}
else if ((propertyInfo = properties.Where(p => p.Name.Equals(kvp.Key, StringComparison.OrdinalIgnoreCase)).FirstOrDefault()) != null)
{
predicate.AppendFormat(" AND [{0}] = @{0}", propertyInfo.Name);
parameters.Add(string.Format("@{0}", propertyInfo.Name), ChangeType(kvp.Value, propertyInfo.PropertyType));
}
}
if (result.QueryParameters.Skip.HasValue ^ result.QueryParameters.Take.HasValue)
{
result.Ok = false;
result.Error = "Skip and take must both have values if either is used";
return(result);
}
var predicateString = predicate.ToString();
if (predicateString.Length > "WHERE 1 = 1 ".Length)
{
result.QueryParameters.Predicate = predicateString;
}
if (parameters.ParameterNames.Any())
{
result.QueryParameters.Parameters = parameters;
}
var orderByString = orderBy.ToString();
orderByString = orderByString.TrimEnd(new char[] { ',' });
if (orderByString.Length > "ORDER BY ".Length)
{
result.QueryParameters.Sort = orderByString;
}
return(result);
}
