rm empty uris and replace _ with ' ' in id

gfl-plugin/src/main/resources/gfl-indexer.xslt

@@ -82,7 +82,7 @@ Refer to comments in the code to understand the used algorithm.
          <doc>
             <field name="entity_name">
                <xsl:value-of select="./parent::name/normalize-space()"/> 
-            </field>
+            </field>    
             <field name ="doctype">
                <xsl:value-of select="./parent::name/@type"/>
             </field>
@@ -97,14 +97,21 @@ Refer to comments in the code to understand the used algorithm.
          <xsl:for-each select="bibl">
             <doc>
                <field name="id"> 
-                  <xsl:value-of select="./@xml:id"/>
+                  <xsl:value-of select="replace(./@xml:id , '_', ' ')"/>
                </field>
                <field name="doctype">literature</field>
                   <xsl:for-each select="relatedItem">
-                  <field name="uri">
-                     <xsl:value-of select="ref/@target"/>
-                  </field>
-                  </xsl:for-each>                  
+                    <xsl:choose>
+                       <xsl:when test="ref/@target = 'https://_' or ref/@target = '' or ref/@target = '_'">
+                          <field name="uri"/>
+                       </xsl:when>
+                       <xsl:otherwise>
+                          <field name="uri">
+                             <xsl:value-of select="ref/@target"/>
+                          </field>
+                       </xsl:otherwise>
+                    </xsl:choose>         
+                  </xsl:for-each>     
                <xsl:for-each select="author">
                   <field name="literature_author"> 
                      <xsl:value-of select="."/>
@@ -139,11 +146,6 @@ Refer to comments in the code to understand the used algorithm.
                <field name="idno">
                   <xsl:value-of select="idno"/> 
                </field>
-               <xsl:for-each select="relatedItem">
-                  <field name="refs"> 
-                     <xsl:value-of select="./normalize-space()"/>
-                  </field>
-               </xsl:for-each>
            </doc>
            </xsl:for-each>
    </xsl:template>

solr/gfl/conf/schema.xml

@@ -67,7 +67,7 @@
   <field name="publisher" type="string" multiValued="true"/>
   <field name="pub_date" type="string" multiValued="true"/>
   <field name="idno" type="string" />
-  <field name="refs" type="string" multiValued="true" />
+ 
 
     
    <!-- for doctype 'page' -->
@@ -96,6 +96,7 @@
   <field name="free_keyword" type="text_de" multiValued="true" />
   <field name="note_comment" type="text_de" multiValued="true" />
   <field name="image_id" type="string" multiValued="true"/>
+  
   <field name="type_refs" type="string" multiValued="true"/>
   <field name="target" type="string" multiValued="true"/>
   <field name="ref_refs" type="string" multiValued="true"/>