delete(): allow batch delete by id

In order to speed up batch deletes, Solr supports sending multiple
document id values in a single command:

  <doc>
    <id>3</id>
    <id>14</id>
    <id>15</id>
    <id>62</id>
  </doc>

Author: Cosimo Streppone

README.rst

@@ -92,9 +92,12 @@ Basic usage looks like:
     # correctly.
     similar = solr.more_like_this(q='id:doc_2', mltfl='text')
 
-    # Finally, you can delete either individual documents...
+    # Finally, you can delete either individual documents,
     solr.delete(id='doc_1')
 
+    # also in batches...
+    solr.delete(id=['doc_1', 'doc_2'])
+
     # ...or all documents.
     solr.delete(q='*:*')
 

pysolr.py

@@ -803,7 +803,8 @@ def delete(self, id=None, q=None, commit=True, waitFlush=None, waitSearcher=None
         Deletes documents.
 
         Requires *either* ``id`` or ``query``. ``id`` is if you know the
-        specific document id to remove. ``query`` is a Lucene-style query
+        specific document id to remove. Note that ``id`` can also be a list of
+        document ids to be deleted. ``query`` is a Lucene-style query
         indicating a collection of documents to delete.
 
         Optionally accepts ``commit``. Default is ``True``.
@@ -815,6 +816,7 @@ def delete(self, id=None, q=None, commit=True, waitFlush=None, waitSearcher=None
         Usage::
 
             solr.delete(id='doc_12')
+            solr.delete(id=['doc_1', 'doc_3'])
             solr.delete(q='*:*')
 
         """
@@ -823,7 +825,12 @@ def delete(self, id=None, q=None, commit=True, waitFlush=None, waitSearcher=None
         elif id is not None and q is not None:
             raise ValueError('You many only specify "id" OR "q", not both.')
         elif id is not None:
-            m = '<delete><id>%s</id></delete>' % id
+            m = '<delete>'
+            if type(id) not in (list, set):
+                id = [ id ]
+            for i in id:
+                m += '<id>%s</id>' % i
+            m += '</delete>'
         elif q is not None:
             m = '<delete><query>%s</query></delete>' % q
 

tests/client.py

@@ -455,6 +455,14 @@ def test_delete(self):
         self.solr.delete(q='*:*')
         self.assertEqual(len(self.solr.search('*:*')), 0)
 
+        # Try delete with a list of document ids
+        self.solr.add(self.docs)
+        self.solr.commit()
+        self.assertEqual(len(self.solr.search('*:*')), len(self.docs))
+        to_delete = [doc['id'] for doc in self.docs]
+        self.solr.delete(id=to_delete)
+        self.assertEqual(len(self.solr.search('*:*')), 0)
+
         # Need at least one.
         self.assertRaises(ValueError, self.solr.delete)
         # Can't have both.