Incorrect display of compound primary keys with foreign key relationships

[simonw]

https://registry.datasette.io/registry-7d4f81f/datasette_tags

Underlying JSON looks like this:

{
    "database": "registry",
    "table": "datasette_tags",
    "is_view": false,
    "human_description_en": "",
    "rows": [
        {
            "datasette_id": {
                "value": 1,
                "label": "Global Power Plant Database"
            },
            "tag": {
                "value": "geospatial",
                "label": "geospatial"
            }
        },

Bug is likely somewhere in here:

datasette/datasette/views/table.py

Lines 143 to 207 in e04f5b0

	if link_column:
	cells.append(
	{
	"column": pks[0] if len(pks) == 1 else "Link",
	"value": jinja2.Markup(
	'<a href="/{database}/{table}/{flat_pks_quoted}">{flat_pks}</a>'.format(
	database=database,
	table=urllib.parse.quote_plus(table),
	flat_pks=str(
	jinja2.escape(
	path_from_row_pks(row, pks, not pks, False)
	)
	),
	flat_pks_quoted=path_from_row_pks(row, pks, not pks),
	)
	),
	}
	)
	for value, column_dict in zip(row, columns):
	column = column_dict["name"]
	if link_column and len(pks) == 1 and column == pks[0]:
	# If there's a simple primary key, don't repeat the value as it's
	# already shown in the link column.
	continue
	if isinstance(value, dict):
	# It's an expanded foreign key - display link to other row
	label = value["label"]
	value = value["value"]
	# The table we link to depends on the column
	other_table = column_to_foreign_key_table[column]
	link_template = (
	LINK_WITH_LABEL if (label != value) else LINK_WITH_VALUE
	)
	display_value = jinja2.Markup(link_template.format(
	database=database,
	table=urllib.parse.quote_plus(other_table),
	link_id=urllib.parse.quote_plus(str(value)),
	id=str(jinja2.escape(value)),
	label=str(jinja2.escape(label)),
	))
	elif value is None:
	display_value = jinja2.Markup("&nbsp;")
	elif is_url(str(value).strip()):
	display_value = jinja2.Markup(
	'<a href="{url}">{url}</a>'.format(
	url=jinja2.escape(value.strip())
	)
	)
	elif column in table_metadata.get("units", {}) and value != "":
	# Interpret units using pint
	value = value * ureg(table_metadata["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 = jinja2.Markup(
	"{:~P}".format(value).replace(" ", "&nbsp;")
	)
	else:
	display_value = str(value)
	cells.append({"column": column, "value": display_value})
	cell_rows.append(cells)

[simonw]

Demo of fix: https://latest.datasette.io/fixtures-e14e080/searchable_tags

[simonw]

Fixed here too now: https://registry.datasette.io/registry-c10707b/datasette_tags