source: csv: Load src_url as str

Fixes: #207

Author: aghinsa

CHANGELOG.md

@@ -29,6 +29,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Develop service running one off operations correctly json-loads dict types.
 - Operations with configs can be run via the development service
 - JSON dumping numpy int\* and float\* caused crash on dump.
+- CSV source always loads `src_urls` as strings.
 ### Removed
 - CLI command `operations` removed in favor of `dataflow run`
 - Duplicate dataflow diagram code from development service

dffml/source/csv.py

@@ -103,7 +103,7 @@ async def read_csv(self, fd, open_file):
                 del row[self.config.labelcol]
             index.setdefault(label, 0)
             # Grab src_url from row
-            src_url = row.get(self.config.key, index[label])
+            src_url = row.get(self.config.key, str(index[label]))
             if self.config.key in row:
                 del row[self.config.key]
             else: