From 981774e3731dfb10f20786deca56d3328cd15649 Mon Sep 17 00:00:00 2001
From: Diego Giovane Pasqualin <d.pasqualin@kendaxa.com>
Date: Sat, 11 Jan 2020 15:27:20 +0100
Subject: [PATCH] Add search_as_you_type datatype

---
 elasticsearch_dsl/field.py     |  8 ++++
 examples/search_as_you_type.py | 79 ++++++++++++++++++++++++++++++++++
 2 files changed, 87 insertions(+)
 create mode 100644 examples/search_as_you_type.py

diff --git a/elasticsearch_dsl/field.py b/elasticsearch_dsl/field.py
index 5a2c0f048..61a9bf05e 100644
--- a/elasticsearch_dsl/field.py
+++ b/elasticsearch_dsl/field.py
@@ -266,6 +266,14 @@ class Text(Field):
     }
     name = 'text'
 
+class SearchAsYouType(Field):
+    _param_defs = {
+        'analyzer': {'type': 'analyzer'},
+        'search_analyzer': {'type': 'analyzer'},
+        'search_quote_analyzer': {'type': 'analyzer'},
+    }
+    name = 'search_as_you_type'
+
 class Keyword(Field):
     _param_defs = {
         'fields': {'type': 'field', 'hash': True},
diff --git a/examples/search_as_you_type.py b/examples/search_as_you_type.py
new file mode 100644
index 000000000..4668c43d0
--- /dev/null
+++ b/examples/search_as_you_type.py
@@ -0,0 +1,79 @@
+# -*- coding: utf-8 -*-
+"""
+Example ``Document`` with search_as_you_type field datatype and how to search it.
+
+When creating a field with search_as_you_type datatype ElasticSearch creates additional subfields to enable efficient
+as-you-type completion, matching terms at any position within the input.
+
+To custom analyzer with ascii folding allow search to work in different languages.
+"""
+from __future__ import print_function, unicode_literals
+
+from elasticsearch_dsl import connections, Document, analyzer, token_filter, SearchAsYouType
+from elasticsearch_dsl.query import MultiMatch
+
+# custom analyzer for names
+ascii_fold = analyzer(
+    'ascii_fold',
+    # we don't want to split O'Brian or Toulouse-Lautrec
+    tokenizer='whitespace',
+    filter=[
+        'lowercase',
+        token_filter('ascii_fold', 'asciifolding')
+    ]
+)
+
+
+class Person(Document):
+    name = SearchAsYouType(max_shingle_size=3)
+
+    class Index:
+        name = 'test-search-as-you-type'
+        settings = {
+            'number_of_shards': 1,
+            'number_of_replicas': 0
+        }
+
+
+if __name__ == '__main__':
+    # initiate the default connection to elasticsearch
+    connections.create_connection()
+
+    # create the empty index
+    Person.init()
+
+    import pprint
+    pprint.pprint(Person().to_dict(), indent=2)
+
+    # index some sample data
+    names = [
+        'Andy Warhol',
+        'Alphonse Mucha',
+        'Henri de Toulouse-Lautrec',
+        'Jára Cimrman',
+    ]
+    for id, name in enumerate(names):
+        Person(_id=id, name=name).save()
+
+    # refresh index manually to make changes live
+    Person._index.refresh()
+
+    # run some suggestions
+    for text in ('já', 'Cimr', 'toulouse', 'Henri Tou', 'a'):
+        s = Person.search()
+
+        s.query = MultiMatch(
+            query=text,
+            type="bool_prefix",
+            fields=[
+                "name",
+                "name._2gram",
+                "name._3gram"
+            ]
+        )
+
+        response = s.execute()
+
+        # print out all the options we got
+        for h in response:
+            print('%15s: %25s' % (text, h.name))