Reorder columns before returning results

Author: juanmcloaiza

astroquery/eso/core.py

@@ -38,7 +38,7 @@
 from ..query import QueryWithLogin
 from ..utils import schema
 from .utils import py2adql, _split_str_as_list_of_str, \
-    adql_sanitize_val, are_coords_valid
+    adql_sanitize_val, are_coords_valid, reorder_columns
 
 __doctest_skip__ = ['EsoClass.*']
 
@@ -301,6 +301,7 @@ def query_tap_service(self,
         table_to_return = None
         tap_service = self._tap_service(authenticated)
         table_to_return = self._try_download_pyvo_table(query_str, tap_service)
+        table_to_return = reorder_columns(table_to_return)
         return table_to_return
 
     @unlimited_max_rec

astroquery/eso/tests/test_eso.py

@@ -18,7 +18,8 @@
 
 from astroquery.utils.mocks import MockResponse
 from ...eso import Eso
-from ...eso.utils import py2adql, adql_sanitize_val
+from ...eso.utils import py2adql, adql_sanitize_val, reorder_columns, \
+    DEFAULT_LEAD_COLS_RAW
 from ...exceptions import NoResultsWarning, MaxResultsWarning
 
 DATA_DIR = os.path.join(os.path.dirname(__file__), 'data')
@@ -333,6 +334,24 @@ def test_issue_table_length_warnings():
     eso_instance._maybe_warn_about_table_length(t)
 
 
+def test_reorder_columns(monkeypatch):
+    eso = Eso()
+    monkeypatch.setattr(eso, 'query_tap_service', monkey_tap)
+    table = eso.query_main(target='SGR A', object='SGR A')
+    names_before = table.colnames[:]
+    table2 = reorder_columns(table)
+    names_after = table2.colnames[:]
+
+    assert set(DEFAULT_LEAD_COLS_RAW).issubset(names_before)
+    assert set(DEFAULT_LEAD_COLS_RAW).issubset(names_after)
+    assert set(names_before) == set(names_after)
+    assert table != table2
+    assert names_before[:5] != names_after[:5]
+
+    for n in table.colnames:
+        assert table[[n]].values_equal(table2[[n]]), n
+
+
 def test_py2adql():
     """
     #  Example query:

astroquery/eso/utils.py

@@ -3,6 +3,10 @@
 """
 
 from typing import Union, List, Optional
+from astropy.table import Table
+
+DEFAULT_LEAD_COLS_RAW = ['object', 'ra', 'dec', 'dp_id', 'date_obs', 'prog_id']
+DEFAULT_LEAD_COLS_PHASE3 = ['target_name', 's_ra', 's_dec', 'dp_id', 'date_obs', 'proposal_id']
 
 
 def _split_str_as_list_of_str(column_str: str):
@@ -13,6 +17,27 @@ def _split_str_as_list_of_str(column_str: str):
     return column_list
 
 
+def reorder_columns(table: Table,
+                    leading_cols: Optional[List[str]] = None):
+    """
+    Reorders the columns of the pased table so that the
+    colums given by the list leading_cols are first.
+    If no leading cols are passed, it defaults to
+    ['object', 'ra', 'dec', 'dp_id', 'date_obs']
+    Returns a table with the columns reordered.
+    """
+    leading_cols = leading_cols or DEFAULT_LEAD_COLS_RAW
+    first_cols = []
+    last_cols = table.colnames[:]
+    for x in leading_cols:
+        if x in last_cols:
+            last_cols.remove(x)
+            first_cols.append(x)
+    last_cols = first_cols + last_cols
+    table = table[last_cols]
+    return table
+
+
 def adql_sanitize_val(x):
     """
     If the value is a string, put it into single quotes