private void ParseRuleAttributes(XElement rule, UrlRewriteRuleBuilder builder)
{
builder.Name = rule.Attribute(RewriteTags.Name)?.Value;
if (ParseBool(rule, RewriteTags.Enabled, defaultValue: true))
{
builder.Enabled = true;
}
else
{
return;
}
var patternSyntax = ParseEnum(rule, RewriteTags.PatternSyntax, PatternSyntax.ECMAScript);
var stopProcessing = ParseBool(rule, RewriteTags.StopProcessing, defaultValue: false);
var match = rule.Element(RewriteTags.Match);
if (match == null)
{
throw new InvalidUrlRewriteFormatException(rule, "Condition must have an associated match");
}
var action = rule.Element(RewriteTags.Action);
if (action == null)
{
throw new InvalidUrlRewriteFormatException(rule, "Rule does not have an associated action attribute");
}
ParseMatch(match, builder, patternSyntax);
ParseConditions(rule.Element(RewriteTags.Conditions), builder, patternSyntax);
ParseUrlAction(action, builder, stopProcessing);
}
private void ParseMatch(XElement match, UrlRewriteRuleBuilder builder, PatternSyntax patternSyntax)
{
var parsedInputString = match.Attribute(RewriteTags.Url)?.Value;
if (parsedInputString == null)
{
throw new InvalidUrlRewriteFormatException(match, "Match must have Url Attribute");
}
var ignoreCase = ParseBool(match, RewriteTags.IgnoreCase, defaultValue: true);
var negate = ParseBool(match, RewriteTags.Negate, defaultValue: false);
builder.AddUrlMatch(parsedInputString, ignoreCase, negate, patternSyntax);
}
private void ParseRules(XElement?rules, IList <IISUrlRewriteRule> result, bool global)
{
if (rules == null)
{
return;
}
foreach (var rule in rules.Elements(RewriteTags.Rule))
{
var builder = new UrlRewriteRuleBuilder {
Global = global
};
ParseRuleAttributes(rule, builder);
if (builder.Enabled)
{
result.Add(builder.Build());
}
}
}
private void ParseConditions(XElement?conditions, UrlRewriteRuleBuilder builder, PatternSyntax patternSyntax)
{
if (conditions == null)
{
return;
}
var grouping = ParseEnum(conditions, RewriteTags.LogicalGrouping, LogicalGrouping.MatchAll);
var trackAllCaptures = ParseBool(conditions, RewriteTags.TrackAllCaptures, defaultValue: false);
var adds = conditions.Elements(RewriteTags.Add);
if (!adds.Any())
{
return;
}
builder.ConfigureConditionBehavior(grouping, trackAllCaptures);
foreach (var cond in adds)
{
ParseCondition(cond, builder, patternSyntax);
}
}
private void ParseUrlAction(XElement urlAction, UrlRewriteRuleBuilder builder, bool stopProcessing)
{
var actionType = ParseEnum(urlAction, RewriteTags.Type, ActionType.None);
UrlAction action;
switch (actionType)
{
case ActionType.None:
action = new NoneAction(stopProcessing ? RuleResult.SkipRemainingRules : RuleResult.ContinueRules);
break;
case ActionType.Rewrite:
case ActionType.Redirect:
var url = string.Empty;
if (urlAction.Attribute(RewriteTags.Url) != null)
{
url = urlAction.Attribute(RewriteTags.Url) !.Value;
if (string.IsNullOrEmpty(url))
{
throw new InvalidUrlRewriteFormatException(urlAction, "Url attribute cannot contain an empty string");
}
}
var urlPattern = _inputParser.ParseInputString(url, builder.UriMatchPart);
var appendQuery = ParseBool(urlAction, RewriteTags.AppendQueryString, defaultValue: true);
if (actionType == ActionType.Rewrite)
{
action = new RewriteAction(stopProcessing ? RuleResult.SkipRemainingRules : RuleResult.ContinueRules, urlPattern, appendQuery);
}
else
{
var redirectType = ParseEnum(urlAction, RewriteTags.RedirectType, RedirectType.Permanent);
action = new RedirectAction((int)redirectType, urlPattern, appendQuery, !appendQuery, escapeBackReferences: false);
}
break;
case ActionType.AbortRequest:
action = new AbortAction();
break;
case ActionType.CustomResponse:
int statusCode;
if (!int.TryParse(urlAction.Attribute(RewriteTags.StatusCode)?.Value, NumberStyles.None, CultureInfo.InvariantCulture, out statusCode))
{
throw new InvalidUrlRewriteFormatException(urlAction, "A valid status code is required");
}
if (statusCode < 200 || statusCode > 999)
{
throw new NotSupportedException("Status codes must be between 200 and 999 (inclusive)");
}
if (!string.IsNullOrEmpty(urlAction.Attribute(RewriteTags.SubStatusCode)?.Value))
{
throw new NotSupportedException("Substatus codes are not supported");
}
var statusReason = urlAction.Attribute(RewriteTags.StatusReason)?.Value;
var statusDescription = urlAction.Attribute(RewriteTags.StatusDescription)?.Value;
action = new CustomResponseAction(statusCode)
{
StatusReason = statusReason, StatusDescription = statusDescription
};
break;
default:
throw new NotSupportedException($"The action type {actionType} wasn't recognized");
}
builder.AddUrlAction(action);
}
private void ParseCondition(XElement conditionElement, UrlRewriteRuleBuilder builder, PatternSyntax patternSyntax)
{
var ignoreCase = ParseBool(conditionElement, RewriteTags.IgnoreCase, defaultValue: true);
var negate = ParseBool(conditionElement, RewriteTags.Negate, defaultValue: false);
var matchType = ParseEnum(conditionElement, RewriteTags.MatchType, MatchType.Pattern);
var parsedInputString = conditionElement.Attribute(RewriteTags.Input)?.Value;
if (parsedInputString == null)
{
throw new InvalidUrlRewriteFormatException(conditionElement, "Conditions must have an input attribute");
}
var parsedPatternString = conditionElement.Attribute(RewriteTags.Pattern)?.Value;
Condition condition;
switch (patternSyntax)
{
case PatternSyntax.ECMAScript:
{
switch (matchType)
{
case MatchType.Pattern:
{
if (string.IsNullOrEmpty(parsedPatternString))
{
throw new FormatException("Match does not have an associated pattern attribute in condition");
}
condition = new UriMatchCondition(_inputParser, parsedInputString, parsedPatternString, builder.UriMatchPart, ignoreCase, negate);
break;
}
case MatchType.IsDirectory:
{
condition = new Condition(_inputParser.ParseInputString(parsedInputString, builder.UriMatchPart), new IsDirectoryMatch(negate));
break;
}
case MatchType.IsFile:
{
condition = new Condition(_inputParser.ParseInputString(parsedInputString, builder.UriMatchPart), new IsFileMatch(negate));
break;
}
default:
throw new FormatException("Unrecognized matchType");
}
break;
}
case PatternSyntax.Wildcard:
throw new NotSupportedException("Wildcard syntax is not supported");
case PatternSyntax.ExactMatch:
if (string.IsNullOrEmpty(parsedPatternString))
{
throw new FormatException("Match does not have an associated pattern attribute in condition");
}
condition = new Condition(_inputParser.ParseInputString(parsedInputString, builder.UriMatchPart), new ExactMatch(ignoreCase, parsedPatternString, negate));
break;
default:
throw new FormatException("Unrecognized pattern syntax");
}
builder.AddUrlCondition(condition);
}
