jellyfin-server/ServiceStack/Host/RestPath.cs
2016-11-11 14:55:12 -05:00

443 lines
17 KiB
C#

using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using System.Text;
using ServiceStack.Serialization;
namespace ServiceStack.Host
{
public class RestPath
{
private const string WildCard = "*";
private const char WildCardChar = '*';
private const string PathSeperator = "/";
private const char PathSeperatorChar = '/';
private const char ComponentSeperator = '.';
private const string VariablePrefix = "{";
readonly bool[] componentsWithSeparators;
private readonly string restPath;
private readonly string allowedVerbs;
private readonly bool allowsAllVerbs;
public bool IsWildCardPath { get; private set; }
private readonly string[] literalsToMatch;
private readonly string[] variablesNames;
private readonly bool[] isWildcard;
private readonly int wildcardCount = 0;
public int VariableArgsCount { get; set; }
/// <summary>
/// The number of segments separated by '/' determinable by path.Split('/').Length
/// e.g. /path/to/here.ext == 3
/// </summary>
public int PathComponentsCount { get; set; }
/// <summary>
/// The total number of segments after subparts have been exploded ('.')
/// e.g. /path/to/here.ext == 4
/// </summary>
public int TotalComponentsCount { get; set; }
public string[] Verbs
{
get
{
return allowsAllVerbs
? new[] { ActionContext.AnyAction }
: AllowedVerbs.Split(new[] { ',', ' ' }, StringSplitOptions.RemoveEmptyEntries);
}
}
public Type RequestType { get; private set; }
public string Path { get { return this.restPath; } }
public string Summary { get; private set; }
public string Notes { get; private set; }
public bool AllowsAllVerbs { get { return this.allowsAllVerbs; } }
public string AllowedVerbs { get { return this.allowedVerbs; } }
public int Priority { get; set; } //passed back to RouteAttribute
public static string[] GetPathPartsForMatching(string pathInfo)
{
var parts = pathInfo.ToLower().Split(PathSeperatorChar)
.Where(x => !string.IsNullOrEmpty(x)).ToArray();
return parts;
}
public static IEnumerable<string> GetFirstMatchHashKeys(string[] pathPartsForMatching)
{
var hashPrefix = pathPartsForMatching.Length + PathSeperator;
return GetPotentialMatchesWithPrefix(hashPrefix, pathPartsForMatching);
}
public static IEnumerable<string> GetFirstMatchWildCardHashKeys(string[] pathPartsForMatching)
{
const string hashPrefix = WildCard + PathSeperator;
return GetPotentialMatchesWithPrefix(hashPrefix, pathPartsForMatching);
}
private static IEnumerable<string> GetPotentialMatchesWithPrefix(string hashPrefix, string[] pathPartsForMatching)
{
foreach (var part in pathPartsForMatching)
{
yield return hashPrefix + part;
var subParts = part.Split(ComponentSeperator);
if (subParts.Length == 1) continue;
foreach (var subPart in subParts)
{
yield return hashPrefix + subPart;
}
}
}
public RestPath(Type requestType, string path, string verbs, string summary = null, string notes = null)
{
this.RequestType = requestType;
this.Summary = summary;
this.Notes = notes;
this.restPath = path;
this.allowsAllVerbs = verbs == null || verbs == WildCard;
if (!this.allowsAllVerbs)
{
this.allowedVerbs = verbs.ToUpper();
}
var componentsList = new List<string>();
//We only split on '.' if the restPath has them. Allows for /{action}.{type}
var hasSeparators = new List<bool>();
foreach (var component in this.restPath.Split(PathSeperatorChar))
{
if (string.IsNullOrEmpty(component)) continue;
if (component.Contains(VariablePrefix)
&& component.IndexOf(ComponentSeperator) != -1)
{
hasSeparators.Add(true);
componentsList.AddRange(component.Split(ComponentSeperator));
}
else
{
hasSeparators.Add(false);
componentsList.Add(component);
}
}
var components = componentsList.ToArray();
this.TotalComponentsCount = components.Length;
this.literalsToMatch = new string[this.TotalComponentsCount];
this.variablesNames = new string[this.TotalComponentsCount];
this.isWildcard = new bool[this.TotalComponentsCount];
this.componentsWithSeparators = hasSeparators.ToArray();
this.PathComponentsCount = this.componentsWithSeparators.Length;
string firstLiteralMatch = null;
var sbHashKey = new StringBuilder();
for (var i = 0; i < components.Length; i++)
{
var component = components[i];
if (component.StartsWith(VariablePrefix))
{
var variableName = component.Substring(1, component.Length - 2);
if (variableName[variableName.Length - 1] == WildCardChar)
{
this.isWildcard[i] = true;
variableName = variableName.Substring(0, variableName.Length - 1);
}
this.variablesNames[i] = variableName;
this.VariableArgsCount++;
}
else
{
this.literalsToMatch[i] = component.ToLower();
sbHashKey.Append(i + PathSeperatorChar.ToString() + this.literalsToMatch);
if (firstLiteralMatch == null)
{
firstLiteralMatch = this.literalsToMatch[i];
}
}
}
for (var i = 0; i < components.Length - 1; i++)
{
if (!this.isWildcard[i]) continue;
if (this.literalsToMatch[i + 1] == null)
{
throw new ArgumentException(
"A wildcard path component must be at the end of the path or followed by a literal path component.");
}
}
this.wildcardCount = this.isWildcard.Count(x => x);
this.IsWildCardPath = this.wildcardCount > 0;
this.FirstMatchHashKey = !this.IsWildCardPath
? this.PathComponentsCount + PathSeperator + firstLiteralMatch
: WildCardChar + PathSeperator + firstLiteralMatch;
this.IsValid = sbHashKey.Length > 0;
this.UniqueMatchHashKey = sbHashKey.ToString();
this.typeDeserializer = new StringMapTypeDeserializer(this.RequestType);
RegisterCaseInsenstivePropertyNameMappings();
}
private void RegisterCaseInsenstivePropertyNameMappings()
{
foreach (var propertyInfo in RequestType.GetSerializableProperties())
{
var propertyName = propertyInfo.Name;
propertyNamesMap.Add(propertyName.ToLower(), propertyName);
}
}
public bool IsValid { get; set; }
/// <summary>
/// Provide for quick lookups based on hashes that can be determined from a request url
/// </summary>
public string FirstMatchHashKey { get; private set; }
public string UniqueMatchHashKey { get; private set; }
private readonly StringMapTypeDeserializer typeDeserializer;
private readonly Dictionary<string, string> propertyNamesMap = new Dictionary<string, string>();
public static Func<RestPath, string, string[], int> CalculateMatchScore { get; set; }
public int MatchScore(string httpMethod, string[] withPathInfoParts)
{
if (CalculateMatchScore != null)
return CalculateMatchScore(this, httpMethod, withPathInfoParts);
int wildcardMatchCount;
var isMatch = IsMatch(httpMethod, withPathInfoParts, out wildcardMatchCount);
if (!isMatch) return -1;
var score = 0;
//Routes with least wildcard matches get the highest score
score += Math.Max((100 - wildcardMatchCount), 1) * 1000;
//Routes with less variable (and more literal) matches
score += Math.Max((10 - VariableArgsCount), 1) * 100;
//Exact verb match is better than ANY
var exactVerb = httpMethod == AllowedVerbs;
score += exactVerb ? 10 : 1;
return score;
}
/// <summary>
/// For performance withPathInfoParts should already be a lower case string
/// to minimize redundant matching operations.
/// </summary>
/// <param name="httpMethod"></param>
/// <param name="withPathInfoParts"></param>
/// <param name="wildcardMatchCount"></param>
/// <returns></returns>
public bool IsMatch(string httpMethod, string[] withPathInfoParts, out int wildcardMatchCount)
{
wildcardMatchCount = 0;
if (withPathInfoParts.Length != this.PathComponentsCount && !this.IsWildCardPath) return false;
if (!this.allowsAllVerbs && !this.allowedVerbs.Contains(httpMethod.ToUpper())) return false;
if (!ExplodeComponents(ref withPathInfoParts)) return false;
if (this.TotalComponentsCount != withPathInfoParts.Length && !this.IsWildCardPath) return false;
int pathIx = 0;
for (var i = 0; i < this.TotalComponentsCount; i++)
{
if (this.isWildcard[i])
{
if (i < this.TotalComponentsCount - 1)
{
// Continue to consume up until a match with the next literal
while (pathIx < withPathInfoParts.Length && withPathInfoParts[pathIx] != this.literalsToMatch[i + 1])
{
pathIx++;
wildcardMatchCount++;
}
// Ensure there are still enough parts left to match the remainder
if ((withPathInfoParts.Length - pathIx) < (this.TotalComponentsCount - i - 1))
{
return false;
}
}
else
{
// A wildcard at the end matches the remainder of path
wildcardMatchCount += withPathInfoParts.Length - pathIx;
pathIx = withPathInfoParts.Length;
}
}
else
{
var literalToMatch = this.literalsToMatch[i];
if (literalToMatch == null)
{
// Matching an ordinary (non-wildcard) variable consumes a single part
pathIx++;
continue;
}
if (withPathInfoParts.Length <= pathIx || withPathInfoParts[pathIx] != literalToMatch) return false;
pathIx++;
}
}
return pathIx == withPathInfoParts.Length;
}
private bool ExplodeComponents(ref string[] withPathInfoParts)
{
var totalComponents = new List<string>();
for (var i = 0; i < withPathInfoParts.Length; i++)
{
var component = withPathInfoParts[i];
if (string.IsNullOrEmpty(component)) continue;
if (this.PathComponentsCount != this.TotalComponentsCount
&& this.componentsWithSeparators[i])
{
var subComponents = component.Split(ComponentSeperator);
if (subComponents.Length < 2) return false;
totalComponents.AddRange(subComponents);
}
else
{
totalComponents.Add(component);
}
}
withPathInfoParts = totalComponents.ToArray();
return true;
}
public object CreateRequest(string pathInfo, Dictionary<string, string> queryStringAndFormData, object fromInstance)
{
var requestComponents = pathInfo.Split(PathSeperatorChar)
.Where(x => !string.IsNullOrEmpty(x)).ToArray();
ExplodeComponents(ref requestComponents);
if (requestComponents.Length != this.TotalComponentsCount)
{
var isValidWildCardPath = this.IsWildCardPath
&& requestComponents.Length >= this.TotalComponentsCount - this.wildcardCount;
if (!isValidWildCardPath)
throw new ArgumentException(string.Format(
"Path Mismatch: Request Path '{0}' has invalid number of components compared to: '{1}'",
pathInfo, this.restPath));
}
var requestKeyValuesMap = new Dictionary<string, string>();
var pathIx = 0;
for (var i = 0; i < this.TotalComponentsCount; i++)
{
var variableName = this.variablesNames[i];
if (variableName == null)
{
pathIx++;
continue;
}
string propertyNameOnRequest;
if (!this.propertyNamesMap.TryGetValue(variableName.ToLower(), out propertyNameOnRequest))
{
if (string.Equals("ignore", variableName, StringComparison.OrdinalIgnoreCase))
{
pathIx++;
continue;
}
throw new ArgumentException("Could not find property "
+ variableName + " on " + RequestType.GetOperationName());
}
var value = requestComponents.Length > pathIx ? requestComponents[pathIx] : null; //wildcard has arg mismatch
if (value != null && this.isWildcard[i])
{
if (i == this.TotalComponentsCount - 1)
{
// Wildcard at end of path definition consumes all the rest
var sb = new StringBuilder();
sb.Append(value);
for (var j = pathIx + 1; j < requestComponents.Length; j++)
{
sb.Append(PathSeperatorChar + requestComponents[j]);
}
value = sb.ToString();
}
else
{
// Wildcard in middle of path definition consumes up until it
// hits a match for the next element in the definition (which must be a literal)
// It may consume 0 or more path parts
var stopLiteral = i == this.TotalComponentsCount - 1 ? null : this.literalsToMatch[i + 1];
if (!string.Equals(requestComponents[pathIx], stopLiteral, StringComparison.OrdinalIgnoreCase))
{
var sb = new StringBuilder();
sb.Append(value);
pathIx++;
while (!string.Equals(requestComponents[pathIx], stopLiteral, StringComparison.OrdinalIgnoreCase))
{
sb.Append(PathSeperatorChar + requestComponents[pathIx++]);
}
value = sb.ToString();
}
else
{
value = null;
}
}
}
else
{
// Variable consumes single path item
pathIx++;
}
requestKeyValuesMap[propertyNameOnRequest] = value;
}
if (queryStringAndFormData != null)
{
//Query String and form data can override variable path matches
//path variables < query string < form data
foreach (var name in queryStringAndFormData)
{
requestKeyValuesMap[name.Key] = name.Value;
}
}
return this.typeDeserializer.PopulateFromMap(fromInstance, requestKeyValuesMap);
}
public override int GetHashCode()
{
return UniqueMatchHashKey.GetHashCode();
}
}
}