log: stop returning a list of names

... since we only get one at a time.

test/test_tsio.py

@@ -673,17 +673,17 @@ def test_history(engine, tsh):
         {'author': 'aurelien.campeas@pythonian.fr',
          'meta': {},
          'date': pd.Timestamp('2017-02-01 00:00:00+0000', tz='UTC'),
-         'names': ['smallserie']
+         'name': 'smallserie'
         },
         {'author': 'aurelien.campeas@pythonian.fr',
          'meta': {},
          'date': pd.Timestamp('2017-02-02 00:00:00+0000', tz='UTC'),
-         'names': ['smallserie']
+         'name': 'smallserie'
         },
         {'author': 'aurelien.campeas@pythonian.fr',
          'meta': {},
          'date': pd.Timestamp('2017-02-03 00:00:00+0000', tz='UTC'),
-         'names': ['smallserie']
+         'name': 'smallserie'
         }
     ] == [{k: v for k, v in log.items() if k != 'rev'}
           for log in logs]

tshistory/cli.py

@@ -36,13 +36,13 @@ date:     {date}
 def format_rev(rev):
     fmt = REVFMT + '\n'
     if rev.get('diff'):
-        fmt += 'series: {names}\n\n'
+        fmt += 'series: {name}\n\n'
         lines = []
         for ts in rev['diff'].values():
             lines.append(ts.to_string())
         fmt += '\n'.join(lines)
     else:
-        fmt += 'series:   {names}'
+        fmt += 'series:   {name}'
 
     return fmt.format(**rev)
 
@@ -129,7 +129,7 @@ def log(db_uri, limit, serie, from_rev, to_rev,
     for rev in tsh.log(engine, limit=limit, names=serie,
                        fromrev=from_rev, torev=to_rev,
                        fromdate=from_insertion_date, todate=to_insertion_date):
-        rev['names'] = ','.join(rev['names'])
+        # rev['name'] = ','.join(rev['names'])
         print(format_rev(rev))
         print()
 

tshistory/tsio.py

@@ -512,7 +512,7 @@ class timeseries(SeriesServices):
             log.append({'rev': csetid, 'author': author,
                         'date': pd.Timestamp(revdate).tz_convert('utc'),
                         'meta': meta or {},
-                        'names': self._changeset_series(cn, csetid)})
+                        'name': self._changeset_series(cn, csetid)})
 
         log.sort(key=lambda rev: rev['rev'])
         return log
@@ -715,16 +715,17 @@ class timeseries(SeriesServices):
         ).scalar()
 
     def _changeset_series(self, cn, csid):
-        sql = ('select seriename '
-               f'from "{self.namespace}".registry as reg, '
-               f'     "{self.namespace}".changeset_series as css '
-               'where css.serie = reg.id '
-               'and   css.cset = %(csid)s')
+        q = sqlq(
+            'seriename'
+        ).relation(
+            f'"{self.namespace}".registry as reg',
+        ).join(
+            f'"{self.namespace}".changeset_series as css on css.serie = reg.id'
+        ).where(
+            'css.cset = %(csid)s', csid=csid
+        )
 
-        return [
-            row.seriename
-            for row in cn.execute(sql, csid=csid).fetchall()
-        ]
+        return q.do(cn).scalar()
 
     def _previous_cset(self, cn, seriename, csid):
         tablename = self._serie_to_tablename(cn, seriename)