PostGIS Testing in Neon

This directory contains configuration files and patches for running PostGIS tests in the Neon database environment.

Overview

PostGIS is a spatial database extension for PostgreSQL that adds support for geographic objects. Testing PostGIS compatibility ensures that Neon's modifications to PostgreSQL don't break compatibility with this critical extension.

PostGIS Versions

• PostgreSQL v17: PostGIS 3.5.0
• PostgreSQL v14/v15/v16: PostGIS 3.3.3

Test Configuration

The test setup includes:

• postgis-no-upgrade-test.patch: Disables upgrade tests by removing the upgrade test section from regress/runtest.mk
• postgis-regular-v16.patch: Version-specific patch for PostgreSQL v16
• postgis-regular-v17.patch: Version-specific patch for PostgreSQL v17
• regular-test.sh: Script to run PostGIS tests as a regular user
• neon-test.sh: Script to handle version-specific test configurations
• raster_outdb_template.sql: Template for raster tests with explicit file paths

Excluded Tests

Important Note: The test exclusions listed below are specifically for regular-user tests against staging instances. These exclusions are necessary because staging instances run with limited privileges and cannot perform operations requiring superuser access. Docker-compose based tests are not affected by these exclusions.

Tests Requiring Superuser Permissions

These tests cannot be run as a regular user:

• estimatedextent
• regress/core/legacy
• regress/core/typmod
• regress/loader/TestSkipANALYZE
• regress/loader/TestANALYZE

Tests Requiring Filesystem Access

These tests need direct filesystem access that is only possible for superusers:

• loader/load_outdb

Tests with Flaky Results

These tests have assumptions that don't always hold true:

• regress/core/computed_columns - Assumes computed columns always outperform alternatives, which is not consistently true

Tests Requiring Tunable Parameter Modifications

These tests attempt to modify the postgis.gdal_enabled_drivers parameter, which is only accessible to superusers:

• raster/test/regress/rt_wkb
• raster/test/regress/rt_addband
• raster/test/regress/rt_setbandpath
• raster/test/regress/rt_fromgdalraster
• raster/test/regress/rt_asgdalraster
• raster/test/regress/rt_astiff
• raster/test/regress/rt_asjpeg
• raster/test/regress/rt_aspng
• raster/test/regress/permitted_gdal_drivers
• Loader tests: BasicOutDB, Tiled10x10, Tiled10x10Copy, Tiled8x8, TiledAuto, TiledAutoSkipNoData, TiledAutoCopyn

Topology Tests (v17 only)

• populate_topology_layer
• renametopogeometrycolumn

Other Modifications

• Binary.sql tests are modified to use explicit file paths
• Server-side SQL COPY commands (which require superuser privileges) are converted to client-side \copy commands
• Upgrade tests are disabled