Search / Similar document improvement.

docs/manual/docs/customizing-application/configuring-search-fields.md

@@ -289,4 +289,58 @@ in `records.json` (eg. adding Danish):
             "any.langdan"
             ]
         },
-```
+```
+
+## Similar documents
+
+
+Similar documents are displayed at the bottom of the record view. 
+
+The more like this query can be configured for the user interface.
+
+* `moreLikeThisSameType` is a boolean to enable or disable the more like this query for the same type of document (eg. suggest series only for a record which is a series).
+* 
+* `moreLikeThisConfig` is the configuration of the more like this query. The configuration is the same as the [Elasticsearch more like this query](https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-mlt-query.html).
+
+
+To configure a more like this query computing similarity between the current record title terms (added to the `like` element) and the title, abstract and tag fields of other records:
+
+```json
+"moreLikeThisConfig": {
+  "more_like_this": {
+    "fields": [
+      "resourceTitleObject.default",
+      "resourceAbstractObject.default",
+      "tag.raw"
+    ],
+    "like": null,
+    "min_term_freq": 1,
+    "min_word_length": 3,
+    "max_query_terms": 35,
+    "minimum_should_match": "70%"
+  }
+},
+```
+
+`like` element can also be used to provide a document to compare with. In this case, the query will compute similarity for the complete document and.also search for current record title terms.
+
+```json
+"moreLikeThisConfig": {
+  "more_like_this": {
+    "like": [
+      {
+      "_id": null
+      }
+    ],
+    "analyzer": "english",
+    "minimum_should_match": "40%"
+  }
+}
+```
+  
+If all your records are in the same language, adding the analyzer to the `more_like_this` query can improve the similarity computation. 
+
+```json
+  "analyzer": "english",
+```
+

web-ui/src/main/resources/catalog/components/search/mdview/mdviewDirective.js

@@ -135,11 +135,27 @@
             };
 
           function buildQuery() {
+            function buildMoreLikeThisFields(fields) {
+              var config = {};
+              angular.copy(moreLikeThisQuery, config);
+              if (Array.isArray(config.more_like_this.like)) {
+                config.more_like_this.like.forEach(function (field) {
+                  if (typeof field === "object" && field._id !== undefined) {
+                    field._id = scope.md.uuid;
+                  }
+                });
+                config.more_like_this.like.push(scope.md.resourceTitle);
+              } else {
+                config.more_like_this.like = scope.md.resourceTitle;
+              }
+              return config;
+            }
+
             var query = gnESFacet.buildDefaultQuery(
               {
                 bool: {
                   must: [
-                    moreLikeThisQuery,
+                    buildMoreLikeThisFields(),
                     { terms: { isTemplate: ["n"] } },
                     // TODO: We may want to use it for subtemplate
                     { terms: { draft: ["n", "e"] } }
@@ -161,23 +177,6 @@
               scope.size
             );
 
-            function setMoreLikeThisFields(fields) {
-              var config = query.query.bool.must[0].more_like_this.like;
-              if (Array.isArray(config)) {
-                config.forEach(function(field) {
-                  if (typeof field === 'object' && field._id !== undefined) {
-                    field._id = scope.md.uuid;
-                  }
-                });
-                config.push(scope.md.resourceTitle);
-              } else {
-                config = scope.md.resourceTitle;
-              }
-              query.query.bool.must[0].more_like_this.like = config;
-            }
-
-            setMoreLikeThisFields();
-
             var resourceType = scope.md.resourceType
               ? scope.md.resourceType[0]
               : undefined;

web-ui/src/main/resources/catalog/js/CatController.js

@@ -314,9 +314,11 @@
             moreLikeThisSameType: true,
             moreLikeThisConfig: {
               more_like_this: {
-                like: [{
-                 "_id": null
-                }],
+                like: [
+                  {
+                    _id: null
+                  }
+                ],
                 analyzer: "english",
                 minimum_should_match: "40%"
               }