Removed units functionality and Pint dependency

Closes #2400, unblocks #2320

datasette/app.py

@@ -37,7 +37,6 @@
 
 from .events import Event
 from .views import Context
-from .views.base import ureg
 from .views.database import database_download, DatabaseView, TableCreateView, QueryView
 from .views.index import IndexView
 from .views.special import (

datasette/filters.py

@@ -368,12 +368,8 @@ class Filters:
     )
     _filters_by_key = {f.key: f for f in _filters}
 
-    def __init__(self, pairs, units=None, ureg=None):
-        if units is None:
-            units = {}
+    def __init__(self, pairs):
         self.pairs = pairs
-        self.units = units
-        self.ureg = ureg
 
     def lookups(self):
         """Yields (lookup, display, no_argument) pairs"""
@@ -413,30 +409,14 @@ def selections(self):
     def has_selections(self):
         return bool(self.pairs)
 
-    def convert_unit(self, column, value):
-        """If the user has provided a unit in the query, convert it into the column unit, if present."""
-        if column not in self.units:
-            return value
-
-        # Try to interpret the value as a unit
-        value = self.ureg(value)
-        if isinstance(value, numbers.Number):
-            # It's just a bare number, assume it's the column unit
-            return value
-
-        column_unit = self.ureg(self.units[column])
-        return value.to(column_unit).magnitude
-
     def build_where_clauses(self, table):
         sql_bits = []
         params = {}
         i = 0
         for column, lookup, value in self.selections():
             filter = self._filters_by_key.get(lookup, None)
             if filter:
-                sql_bit, param = filter.where_clause(
-                    table, column, self.convert_unit(column, value), i
-                )
+                sql_bit, param = filter.where_clause(table, column, value, i)
                 sql_bits.append(sql_bit)
                 if param is not None:
                     if not isinstance(param, list):

datasette/utils/__init__.py

@@ -1368,7 +1368,6 @@ def recursive_move(src, dest, path=None):
     "fts_table",
     "fts_pk",
     "searchmode",
-    "units",
 )
 
 

datasette/views/base.py

@@ -8,8 +8,6 @@
 from markupsafe import escape
 
 
-import pint
-
 from datasette.database import QueryInterrupted
 from datasette.utils.asgi import Request
 from datasette.utils import (
@@ -32,8 +30,6 @@
     BadRequest,
 )
 
-ureg = pint.UnitRegistry()
-
 
 class DatasetteError(Exception):
     def __init__(

datasette/views/row.py

@@ -103,7 +103,6 @@ async def template_data():
             "columns": columns,
             "primary_keys": resolved.pks,
             "primary_key_values": pk_values,
-            "units": (await self.ds.table_config(database, table)).get("units", {}),
         }
 
         if "foreign_key_tables" in (request.args.get("_extras") or "").split(","):

datasette/views/table.py

@@ -43,7 +43,7 @@
 from datasette.utils.asgi import BadRequest, Forbidden, NotFound, Response
 from datasette.filters import Filters
 import sqlite_utils
-from .base import BaseView, DatasetteError, ureg, _error, stream_csv
+from .base import BaseView, DatasetteError, _error, stream_csv
 from .database import QueryView
 
 LINK_WITH_LABEL = (
@@ -292,14 +292,6 @@ async def display_columns_and_rows(
                         ),
                     )
                 )
-            elif column in table_config.get("units", {}) and value != "":
-                # Interpret units using pint
-                value = value * ureg(table_config["units"][column])
-                # Pint uses floating point which sometimes introduces errors in the compact
-                # representation, which we have to round off to avoid ugliness. In the vast
-                # majority of cases this rounding will be inconsequential. I hope.
-                value = round(value.to_compact(), 6)
-                display_value = markupsafe.Markup(f"{value:~P}".replace(" ", " "))
             else:
                 display_value = str(value)
                 if truncate_cells and len(display_value) > truncate_cells:
@@ -1017,7 +1009,6 @@ async def table_view_data(
         nofacet = True
 
     table_metadata = await datasette.table_config(database_name, table_name)
-    units = table_metadata.get("units", {})
 
     # Arguments that start with _ and don't contain a __ are
     # special - things like ?_search= - and should not be
@@ -1029,7 +1020,7 @@ async def table_view_data(
                 filter_args.append((key, v))
 
     # Build where clauses from query string arguments
-    filters = Filters(sorted(filter_args), units, ureg)
+    filters = Filters(sorted(filter_args))
     where_clauses, params = filters.build_where_clauses(table_name)
 
     # Execute filters_from_request plugin hooks - including the default

docs/metadata.rst

@@ -205,100 +205,6 @@ These will be displayed at the top of the table page, and will also show in the
 
 You can see an example of how these look at `latest.datasette.io/fixtures/roadside_attractions <https://latest.datasette.io/fixtures/roadside_attractions>`__.
 
-Specifying units for a column
------------------------------
-
-Datasette supports attaching units to a column, which will be used when displaying
-values from that column. SI prefixes will be used where appropriate.
-
-Column units are configured in the metadata like so:
-
-.. [[[cog
-    metadata_example(cog, {
-        "databases": {
-            "database1": {
-                "tables": {
-                    "example_table": {
-                        "units": {
-                            "column1": "metres",
-                            "column2": "Hz"
-                        }
-                    }
-                }
-            }
-        }
-    })
-.. ]]]
-
-.. tab:: metadata.yaml
-
-    .. code-block:: yaml
-
-        databases:
-          database1:
-            tables:
-              example_table:
-                units:
-                  column1: metres
-                  column2: Hz
-
-
-.. tab:: metadata.json
-
-    .. code-block:: json
-
-        {
-          "databases": {
-            "database1": {
-              "tables": {
-                "example_table": {
-                  "units": {
-                    "column1": "metres",
-                    "column2": "Hz"
-                  }
-                }
-              }
-            }
-          }
-        }
-.. [[[end]]]
-
-
-Units are interpreted using Pint_, and you can see the full list of available units in
-Pint's `unit registry`_. You can also add `custom units`_ to the metadata, which will be
-registered with Pint:
-
-.. [[[cog
-    metadata_example(cog, {
-        "custom_units": [
-            "decibel = [] = dB"
-        ]
-    })
-.. ]]]
-
-.. tab:: metadata.yaml
-
-    .. code-block:: yaml
-
-        custom_units:
-        - decibel = [] = dB
-
-
-.. tab:: metadata.json
-
-    .. code-block:: json
-
-        {
-          "custom_units": [
-            "decibel = [] = dB"
-          ]
-        }
-.. [[[end]]]
-
-.. _Pint: https://pint.readthedocs.io/
-.. _unit registry: https://github.com/hgrecco/pint/blob/master/pint/default_en.txt
-.. _custom units: http://pint.readthedocs.io/en/latest/defining.html
-
 .. _metadata_default_sort:
 
 Setting a default sort order

setup.py

@@ -50,7 +50,6 @@ def get_version():
         "httpx>=0.20",
         'importlib_resources>=1.3.1; python_version < "3.9"',
         'importlib_metadata>=4.6; python_version < "3.10"',
-        "pint>=0.9",
         "pluggy>=1.0",
         "uvicorn>=0.11",
         "aiofiles>=0.4",

tests/fixtures.py

@@ -379,7 +379,6 @@ def generate_sortable_rows(num):
                     ],
                 },
                 "no_primary_key": {"sortable_columns": [], "hidden": True},
-                "units": {"units": {"distance": "m", "frequency": "Hz"}},
                 "primary_key_multiple_columns_explicit_label": {
                     "label_column": "content2"
                 },
@@ -507,16 +506,6 @@ def generate_sortable_rows(num):
   FOREIGN KEY ("foreign_key_with_custom_label") REFERENCES [primary_key_multiple_columns_explicit_label](id)
 );
 
-CREATE TABLE units (
-  pk integer primary key,
-  distance int,
-  frequency int
-);
-
-INSERT INTO units VALUES (1, 1, 100);
-INSERT INTO units VALUES (2, 5000, 2500);
-INSERT INTO units VALUES (3, 100000, 75000);
-
 CREATE TABLE tags (
     tag TEXT PRIMARY KEY
 );

tests/plugins/my_plugin.py

@@ -5,18 +5,21 @@
 from datasette.utils import path_with_added_args
 from datasette.utils.asgi import asgi_send_json, Response
 import base64
-import pint
 import json
-import urllib
-
-ureg = pint.UnitRegistry()
+import urllib.parse
 
 
 @hookimpl
 def prepare_connection(conn, database, datasette):
     def convert_units(amount, from_, to_):
         """select convert_units(100, 'm', 'ft');"""
-        return (amount * ureg(from_)).to(to_).to_tuple()[0]
+        # Convert meters to feet
+        if from_ == "m" and to_ == "ft":
+            return amount * 3.28084
+        # Convert feet to meters
+        if from_ == "ft" and to_ == "m":
+            return amount / 3.28084
+        assert False, "Unsupported conversion"
 
     conn.create_function("convert_units", 3, convert_units)
 

tests/test_api.py

@@ -528,16 +528,6 @@ async def test_database_page(ds_client):
             },
             "private": False,
         },
-        {
-            "name": "units",
-            "columns": ["pk", "distance", "frequency"],
-            "primary_keys": ["pk"],
-            "count": 3,
-            "hidden": False,
-            "fts_table": None,
-            "foreign_keys": {"incoming": [], "outgoing": []},
-            "private": False,
-        },
         {
             "name": "no_primary_key",
             "columns": ["content", "a", "b", "c"],
@@ -1133,7 +1123,6 @@ async def test_config_json(config, expected):
                                 ],
                             },
                             "no_primary_key": {"sortable_columns": [], "hidden": True},
-                            "units": {"units": {"distance": "m", "frequency": "Hz"}},
                             "primary_key_multiple_columns_explicit_label": {
                                 "label_column": "content2"
                             },
@@ -1168,7 +1157,6 @@ async def test_config_json(config, expected):
                                     "text",
                                 ]
                             },
-                            "units": {"units": {"distance": "m", "frequency": "Hz"}},
                             # These one get redacted:
                             "no_primary_key": "***",
                             "primary_key_multiple_columns_explicit_label": "***",

tests/test_internals_database.py

@@ -422,7 +422,6 @@ async def test_table_names(db):
         "table/with/slashes.csv",
         "complex_foreign_keys",
         "custom_foreign_key_label",
-        "units",
         "tags",
         "searchable",
         "searchable_tags",

tests/test_plugins.py

@@ -424,8 +424,8 @@ def extra_template_vars(view_name):
     (
         ("/", "index"),
         ("/fixtures", "database"),
-        ("/fixtures/units", "table"),
-        ("/fixtures/units/1", "row"),
+        ("/fixtures/facetable", "table"),
+        ("/fixtures/facetable/1", "row"),
         ("/-/versions", "json_data"),
         ("/fixtures/-/query?sql=select+1", "database"),
     ),

tests/test_table_api.py

@@ -720,22 +720,6 @@ async def test_view(ds_client):
     ]
 
 
-@pytest.mark.xfail
-@pytest.mark.asyncio
-async def test_unit_filters(ds_client):
-    response = await ds_client.get(
-        "/fixtures/units.json?_shape=arrays&distance__lt=75km&frequency__gt=1kHz"
-    )
-    assert response.status_code == 200
-    data = response.json()
-
-    assert data["units"]["distance"] == "m"
-    assert data["units"]["frequency"] == "Hz"
-
-    assert len(data["rows"]) == 1
-    assert data["rows"][0][0] == 2
-
-
 def test_page_size_matching_max_returned_rows(
     app_client_returned_rows_matches_page_size,
 ):