Add tests for third party table with long identifiers

conftest.py

@@ -54,7 +54,7 @@ def create_db(request, SES_engine_cache):
     A factory for Postgres mathesar-installed databases. A fixture made of this method tears down
     created dbs when leaving scope.
 
-    This method is used to create two fixtures with different scopes, that's why it's not a fixture
+    This method is used to create fixtures with different scopes, that's why it's not a fixture
     itself.
     """
     engine_cache = SES_engine_cache

mathesar/tests/api/test_column_api.py

@@ -9,9 +9,6 @@
 
 from mathesar.api.exceptions.error_codes import ErrorCodes
 from mathesar.tests.api.test_table_api import check_columns_response
-from mathesar.api.exceptions.database_exceptions import (
-    exceptions as database_api_exceptions
-)
 
 
 def test_column_list(column_test_table, client):
@@ -173,22 +170,6 @@ def test_column_create(table_fixture, client, request):
     assert actual_new_col["default"] is None
 
 
-def test_column_create_with_long_column_name(column_test_table, client):
-    very_long_string = ''.join(map(str, range(50)))
-    name = 'very_long_identifier_' + very_long_string
-    db_type = PostgresType.NUMERIC
-    data = {
-        "name": name,
-        "type": db_type.id,
-    }
-    response = client.post(
-        f"/api/db/v0/tables/{column_test_table.id}/columns/",
-        data=data,
-    )
-    assert response.status_code == 400
-    assert response.json()[0]['code'] == database_api_exceptions.IdentifierTooLong.error_code
-
-
 @pytest.mark.parametrize('client_name, expected_status_code', write_client_with_different_roles)
 def test_column_create_by_different_roles(create_patents_table, request, client_name, expected_status_code):
     table_name = 'NASA Constraint List 1'

mathesar/tests/api/test_long_identifiers.py

@@ -0,0 +1,216 @@
+import pytest
+
+from sqlalchemy.sql import text
+
+from django.core.files.base import File
+
+from db.types.base import PostgresType
+from db.identifiers import truncate_if_necessary, POSTGRES_IDENTIFIER_SIZE_LIMIT
+
+from mathesar.api.exceptions.database_exceptions import (
+    exceptions as database_api_exceptions
+)
+from mathesar.models.base import DataFile
+
+from mathesar.tests.api.test_table_api import check_create_table_response, get_expected_name
+
+
+def _get_string_of_length(n):
+    def return_a_character(_):
+        return 'x'
+    return ''.join(map(return_a_character, range(n)))
+
+
+@pytest.fixture
+def long_column_data_file():
+    data_filepath = 'mathesar/tests/data/long_column_names.csv'
+    with open(data_filepath, "rb") as csv_file:
+        data_file = DataFile.objects.create(
+            file=File(csv_file),
+            created_from='file',
+            base_name='longdatafiled',
+            type='csv'
+        )
+    return data_file
+
+
+@pytest.fixture
+def dj_model_of_preexisting_db(worker_id, FUN_create_dj_db, FUN_engine_cache):
+    db_name = f"preexisting_db_{worker_id}"
+    db_model = FUN_create_dj_db(db_name)
+    engine = FUN_engine_cache(db_name)
+    max_length_identifier = _get_string_of_length(
+        POSTGRES_IDENTIFIER_SIZE_LIMIT
+    )
+    with engine.connect() as con:
+        statement = text(f"""
+            CREATE TABLE public.persons (
+                {max_length_identifier} INT PRIMARY KEY
+            );
+        """)
+        con.execute(statement)
+        con.commit()
+    return db_model
+
+
+def test_long_identifier_in_prexisting_db(dj_model_of_preexisting_db, client):  # noqa: F841
+    """
+    Checks that the table and column endpoints work for a third-party db with
+    an identifier that has maximum length supported by Postgres.
+    """
+    response = client.get("/api/db/v0/tables/")
+    json = response.json()
+    assert response.status_code == 200
+    assert json['count'] == 1
+    table_json = json['results'][0]
+    assert table_json['name'] == 'persons'
+    table_id = table_json['id']
+    response = client.get(
+        f"/api/db/v0/tables/{table_id}/columns/",
+    )
+    json = response.json()
+    assert response.status_code == 200
+    column_json = json['results'][0]
+    column_id = column_json['id']
+    assert len(column_json['name']) == POSTGRES_IDENTIFIER_SIZE_LIMIT
+    db_type = PostgresType.BOOLEAN
+    data = {"type": db_type.id}
+    response = client.patch(
+        f"/api/db/v0/tables/{table_id}/columns/{column_id}/", data=data
+    )
+    assert response.status_code == 200
+    json = response.json()
+    column_json = json
+    assert len(column_json['name']) == POSTGRES_IDENTIFIER_SIZE_LIMIT
+
+
+def test_column_create_with_long_column_name(column_test_table, client):
+    very_long_string = ''.join(map(str, range(50)))
+    name = 'very_long_identifier_' + very_long_string
+    db_type = PostgresType.NUMERIC
+    data = {
+        "name": name,
+        "type": db_type.id,
+    }
+    response = client.post(
+        f"/api/db/v0/tables/{column_test_table.id}/columns/",
+        data=data,
+    )
+    assert response.status_code == 400
+    assert response.json()[0]['code'] == database_api_exceptions.IdentifierTooLong.error_code
+
+
+@pytest.mark.parametrize(
+    'before_truncation, after_truncation',
+    [
+        [
+            "bbbbbbbbbbbbbb",
+            "bbbbbbbbbbbbbb",
+        ],
+        [
+            "cccccccccccccccccccccc",
+            "cccccccccccccccccccccc",
+        ],
+        [
+            "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
+            "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
+        ],
+        [
+            "ffffffffffffffffffffffffffffffffffffffffffffffffffffffffff",
+            "fffffffffffffffffffffffffffffffffffffff-7e43d30e"
+        ],
+        [
+            "eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee",
+            "eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee-d0ccef3c",
+        ],
+        [
+            "ggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggg",
+            "ggggggggggggggggggggggggggggggggggggggg-2910cecf",
+        ],
+    ]
+)
+def test_truncate_if_necessary(before_truncation, after_truncation):
+    assert truncate_if_necessary(before_truncation) == after_truncation
+
+
+def test_create_table_long_name_data_file(client, long_column_data_file, create_schema, uid):
+    table_name = 'My Long column name datafile'
+    # response, response_table, table = _create_table(
+    # )
+    expt_name = get_expected_name(table_name, data_file=long_column_data_file)
+    first_row = (
+        1, 'NATION', '8.6', '4.5', '8.5', '4.3', '8.3', '4.6', '78.6', '2.22',
+        '0.88', '0.66', '1.53', '3.75', '3.26', '0.45', '0.07', '53.9', '52.3',
+        '0.8', '0.38487', '3.15796', '2.3', '33247', '14.842144', '6.172333',
+        '47.158545', '1.698662', '2.345577', '7.882694', '0.145406', '3.395302',
+        '92.085375', '14.447634', '78.873848', '1.738571', '16.161024',
+        '19.436701', '8.145643', '94.937079', '74.115131', '75.601680',
+        '22.073834', '11.791045', '1.585233',
+        '1.016932', '2023-02-01'
+    )
+    column_names = [
+        "State or Nation",
+        "Cycle 1 Total Number of Health Deficiencies",
+        "Cycle 1 Total Number of Fire Safety Deficiencies",
+        "Cycle 2 Total Number of Health Deficiencies",
+        "Cycle 2 Total Number of Fire Safety Deficiencies",
+        "Cycle 3 Total Number of Health Deficiencies",
+        "Cycle 3 Total Number of Fire Safety Deficiencies",
+        "Average Number of Residents per Day",
+        "Reported Nurse Aide Staffing Hours per Resident per Day",
+        "Reported LPN Staffing Hours per Resident per Day",
+        "Reported RN Staffing Hours per Resident per Day",
+        "Reported Licensed Staffing Hours per Resident per Day",
+        "Reported Total Nurse Staffing Hours per Resident per Day",
+        "Total number of nurse staff hours per resident per day on the weekend",
+        "Registered Nurse hours per resident per day on the weekend",
+        "Reported Physical Therapist Staffing Hours per Resident Per Day",
+        "Total nursing staff turnover",
+        "Registered Nurse turnover",
+        "Number of administrators who have left the nursing home",
+        "Case-Mix RN Staffing Hours per Resident per Day",
+        "Case-Mix Total Nurse Staffing Hours per Resident per Day",
+        "Number of Fines",
+        "Fine Amount in Dollars",
+        "Percentage of long stay residents whose need for help with daily activities has increased",
+        "Percentage of long stay residents who lose too much weight",
+        "Percentage of low risk long stay residents who lose control of their bowels or bladder",
+        "Percentage of long stay residents with a catheter inserted and left in their bladder",
+        "Percentage of long stay residents with a urinary tract infection",
+        "Percentage of long stay residents who have depressive symptoms",
+        "Percentage of long stay residents who were physically restrained",
+        "Percentage of long stay residents experiencing one or more falls with major injury",
+        "Percentage of long stay residents assessed and appropriately given the pneumococcal vaccine",
+        "Percentage of long stay residents who received an antipsychotic medication",
+        "Percentage of short stay residents assessed and appropriately given the pneumococcal vaccine",
+        "Percentage of short stay residents who newly received an antipsychotic medication",
+        "Percentage of long stay residents whose ability to move independently worsened",
+        "Percentage of long stay residents who received an antianxiety or hypnotic medication",
+        "Percentage of high risk long stay residents with pressure ulcers",
+        "Percentage of long stay residents assessed and appropriately given the seasonal influenza vaccine",
+        "Percentage of short stay residents who made improvements in function",
+        "Percentage of short stay residents who were assessed and appropriately given the seasonal influenza vaccine",
+        "Percentage of short stay residents who were rehospitalized after a nursing home admission",
+        "Percentage of short stay residents who had an outpatient emergency department visit",
+        "Number of hospitalizations per 1000 long-stay resident days",
+        "Number of outpatient emergency department visits per 1000 long-stay resident days",
+        "Processing Date"
+    ]
+    # Make sure at least some column names require truncation;
+    # 63 is the hard Postgres limit; we're also experiencing problems with ids
+    # as short as 58 characters, but I'll leave this at 63 so that it doesn't
+    # have to be updated once that's fixed.
+    assert any(
+        len(column_name) >= 63
+        for column_name
+        in column_names
+    )
+    processed_column_names = [truncate_if_necessary(col) for col in column_names]
+    schema = create_schema(uid)
+    table = check_create_table_response(
+        client, table_name, expt_name, long_column_data_file, schema, first_row,
+        processed_column_names, import_target_table=None
+    )
+    # This just makes sure we can get records. This was a bug with long column names.
+    response = client.get(f'/api/db/v0/tables/{table.id}/records/')
+    assert response.status_code == 200