Add UDF support to write table

README.md

@@ -168,6 +168,34 @@ try:
 except BigQueryTimeoutException:
     print "Timeout"
 
+# write to permanent table with UDF in query string
+external_udf_uris = ["gs://bigquery-sandbox-udf/url_decode.js"]
+query = """SELECT requests, title
+            FROM
+              urlDecode(
+                SELECT
+                  title, sum(requests) AS num_requests
+                FROM
+                  [fh-bigquery:wikipedia.pagecounts_201504]
+                WHERE language = 'fr'
+                GROUP EACH BY title
+              )
+            WHERE title LIKE '%ç%'
+            ORDER BY requests DESC
+            LIMIT 100
+        """
+job = client.write_to_table(
+  query,
+  'dataset',
+  'table',
+  external_udf_uris=external_udf_uris
+)
+
+try:
+    job_resource = client.wait_for_job(job, timeout=60)
+    print job_resource
+except BigQueryTimeoutException:
+    print "Timeout"
 
 # write to temporary table
 job = client.write_to_table('SELECT * FROM dataset.original_table LIMIT 100')
@@ -176,6 +204,8 @@ try:
     print job_resource
 except BigQueryTimeoutException:
     print "Timeout"
+
+
 ```
 
 # Import data from Google cloud storage

bigquery/client.py

@@ -861,6 +861,7 @@ def write_to_table(
             query,
             dataset=None,
             table=None,
+            external_udf_uris=[],
             allow_large_results=None,
             use_query_cache=None,
             priority=None,
@@ -874,6 +875,11 @@ def write_to_table(
             query: required BigQuery query string.
             dataset: optional string id of the dataset
             table: optional string id of the table
+            external_udf_uris: optional list of external UDF URIs
+                    (if given,
+                        URIs must be Google Cloud Storage
+                        and have .js extensions
+                    )
             allow_large_results: optional boolean
             use_query_cache: optional boolean
             priority: optional string
@@ -919,6 +925,14 @@ def write_to_table(
         if write_disposition:
             configuration['writeDisposition'] = write_disposition
 
+        configuration['userDefinedFunctionResources'] = []
+        for external_udf_uri in external_udf_uris:
+            configuration['userDefinedFunctionResources'].append(
+                {
+                    "resourceUri": external_udf_uri
+                }
+            )
+
         body = {
             "configuration": {
                 'query': configuration
@@ -1230,7 +1244,7 @@ def _transform_row(self, row, schema):
 
             elif col_dict['type'] == 'BOOLEAN':
                 row_value = row_value in ('True', 'true', 'TRUE')
-            
+
             elif col_dict['type'] == 'TIMESTAMP':
                 row_value = float(row_value)
 

bigquery/tests/test_client.py

@@ -1012,6 +1012,7 @@ def setUp(self):
         self.project_id = 'project'
         self.dataset_id = 'dataset'
         self.table_id = 'table'
+        self.external_udf_uris = ['gs://bucket/external_udf.js']
         self.use_query_cache = False
         self.priority = "INTERACTIVE"
         self.client = client.BigQueryClient(self.mock_api,
@@ -1032,6 +1033,9 @@ def test_write(self):
                         "tableId": self.table_id
                     },
                     "query": self.query,
+                    "userDefinedFunctionResources": [{
+                        "resourceUri": self.external_udf_uris[0]
+                    }],
                     "useQueryCache": self.use_query_cache,
                     "priority": self.priority,
                 }
@@ -1042,6 +1046,7 @@ def test_write(self):
         result = self.client.write_to_table(self.query,
                                             self.dataset_id,
                                             self.table_id,
+                                            external_udf_uris=self.external_udf_uris,
                                             use_query_cache=False,
                                             priority=self.priority)