New: (Cardigann) Allow JSON filters

Fixes #844

src/NzbDrone.Core/IndexerVersions/IndexerDefinitionUpdateService.cs

@@ -28,7 +28,7 @@ namespace NzbDrone.Core.IndexerVersions
         /* Update Service will fall back if version # does not exist for an indexer  per Ta */
 
         private const string DEFINITION_BRANCH = "master";
-        private const int DEFINITION_VERSION = 4;
+        private const int DEFINITION_VERSION = 5;
 
         //Used when moving yml to C#
         private readonly List<string> _defintionBlocklist = new List<string>()

src/NzbDrone.Core/Indexers/Definitions/Cardigann/CardigannBase.cs

@@ -48,6 +48,9 @@ namespace NzbDrone.Core.Indexers.Cardigann
         protected static readonly Regex _LogicFunctionRegex = new Regex(
             $@"\b({string.Join("|", _SupportedLogicFunctions.Select(Regex.Escape))})(?:\s+(\(?\.[^\)\s]+\)?|""[^""]+"")){{2,}}");
 
+        // Matches CSS selectors for the JSON parser
+        protected static readonly Regex _jsonSelectorRegex = new Regex(@"\:(?<filter>.+?)\((?<key>.+?)\)(?=:|\z)", RegexOptions.Compiled);
+
         public CardigannSettings Settings { get; set;  }
 
         public CardigannBase(IConfigService configService,
@@ -234,13 +237,20 @@ namespace NzbDrone.Core.Indexers.Cardigann
 
             if (selector.Selector != null)
             {
-                var selector_Selector = ApplyGoTemplateText(selector.Selector.TrimStart('.'), variables);
+                var selectorSelector = ApplyGoTemplateText(selector.Selector.TrimStart('.'), variables);
-                var selection = parentObj.SelectToken(selector_Selector);
+                selectorSelector = JsonParseFieldSelector(parentObj, selectorSelector);
+
+                JToken selection = null;
+                if (selectorSelector != null)
+                {
+                    selection = parentObj.SelectToken(selectorSelector);
+                }
+
                 if (selection == null)
                 {
                     if (required)
                     {
-                        throw new Exception(string.Format("Selector \"{0}\" didn't match {1}", selector_Selector, parentObj.ToString()));
+                        throw new Exception(string.Format("Selector \"{0}\" didn't match {1}", selectorSelector, parentObj.ToString()));
                     }
 
                     return null;
@@ -851,5 +861,89 @@ namespace NzbDrone.Core.Indexers.Cardigann
 
             return settingsBaseUrl;
         }
+
+        protected JArray JsonParseRowsSelector(JToken parsedJson, string rowSelector)
+        {
+            var selector = rowSelector.Split(':')[0];
+            var rowsObj = parsedJson.SelectToken(selector).Value<JArray>();
+            return new JArray(rowsObj.Where(t =>
+                                                JsonParseFieldSelector(t.Value<JObject>(), rowSelector.Remove(0, selector.Length)) != null));
+        }
+
+        private string JsonParseFieldSelector(JToken parsedJson, string rowSelector)
+        {
+            var selector = rowSelector.Split(':')[0];
+            JToken parsedObject;
+            if (string.IsNullOrWhiteSpace(selector))
+            {
+                parsedObject = parsedJson;
+            }
+            else if (parsedJson.SelectToken(selector) != null)
+            {
+                parsedObject = parsedJson.SelectToken(selector);
+            }
+            else
+            {
+                return null;
+            }
+
+            foreach (Match match in _jsonSelectorRegex.Matches(rowSelector))
+            {
+                var filter = match.Result("${filter}");
+                var key = match.Result("${key}");
+                Match innerMatch;
+                switch (filter)
+                {
+                    case "has":
+                        innerMatch = _jsonSelectorRegex.Match(key);
+                        if (innerMatch.Success)
+                        {
+                            if (JsonParseFieldSelector(parsedObject, key) == null)
+                            {
+                                return null;
+                            }
+                        }
+                        else
+                        {
+                            if (parsedObject.SelectToken(key) == null)
+                            {
+                                return null;
+                            }
+                        }
+
+                        break;
+                    case "not":
+                        innerMatch = _jsonSelectorRegex.Match(key);
+                        if (innerMatch.Success)
+                        {
+                            if (JsonParseFieldSelector(parsedObject, key) != null)
+                            {
+                                return null;
+                            }
+                        }
+                        else
+                        {
+                            if (parsedObject.SelectToken(key) != null)
+                            {
+                                return null;
+                            }
+                        }
+
+                        break;
+                    case "contains":
+                        if (!parsedObject.ToString().Contains(key))
+                        {
+                            return null;
+                        }
+
+                        break;
+                    default:
+                        _logger.Error(string.Format("CardigannIndexer ({0}): Unsupported selector: {1}", _definition.Id, rowSelector));
+                        continue;
+                }
+            }
+
+            return selector;
+        }
     }
 }

src/NzbDrone.Core/Indexers/Definitions/Cardigann/CardigannDefinition.cs

@@ -151,6 +151,7 @@ namespace NzbDrone.Core.Indexers.Cardigann
         public int After { get; set; }
         public SelectorBlock Dateheaders { get; set; }
         public SelectorBlock Count { get; set; }
+        public bool Multiple { get; set; } = false;
     }
 
     public class SearchPathBlock : RequestBlock
@@ -200,8 +201,6 @@ namespace NzbDrone.Core.Indexers.Cardigann
     public class ResponseBlock
     {
         public string Type { get; set; }
-        public string Attribute { get; set; }
-        public bool Multiple { get; set; }
         public string NoResultsMessage { get; set; }
     }
 }

src/NzbDrone.Core/Indexers/Definitions/Cardigann/CardigannParser.cs

@@ -83,16 +83,16 @@ namespace NzbDrone.Core.Indexers.Cardigann
                     }
                 }
 
-                var rowsObj = parsedJson.SelectToken(search.Rows.Selector);
+                var rowsArray = JsonParseRowsSelector(parsedJson, search.Rows.Selector);
-                if (rowsObj == null)
+                if (rowsArray == null)
                 {
                     throw new IndexerException(indexerResponse, "Error Parsing Rows Selector");
                 }
 
-                foreach (var row in rowsObj.Value<JArray>())
+                foreach (var row in rowsArray)
                 {
-                    var selObj = request.SearchPath.Response.Attribute != null ? row.SelectToken(request.SearchPath.Response.Attribute).Value<JToken>() : row;
+                    var selObj = search.Rows.Attribute != null ? row.SelectToken(search.Rows.Attribute).Value<JToken>() : row;
-                    var mulRows = request.SearchPath.Response.Multiple == true ? selObj.Values<JObject>() : new List<JObject> { selObj.Value<JObject>() };
+                    var mulRows = search.Rows.Multiple ? selObj.Values<JObject>() : new List<JObject> { selObj.Value<JObject>() };
 
                     foreach (var mulRow in mulRows)
                     {

src/NzbDrone.Core/Indexers/Definitions/Cardigann/CardigannRequest.cs

@@ -8,13 +8,6 @@ namespace NzbDrone.Core.Indexers.Cardigann
         public Dictionary<string, object> Variables { get; private set; }
         public SearchPathBlock SearchPath { get; private set; }
 
-        public CardigannRequest(string url, HttpAccept httpAccept, Dictionary<string, object> variables, SearchPathBlock searchPath)
-            : base(url, httpAccept)
-        {
-            Variables = variables;
-            SearchPath = searchPath;
-        }
-
         public CardigannRequest(HttpRequest httpRequest, Dictionary<string, object> variables, SearchPathBlock searchPath)
             : base(httpRequest)
         {