Add framework for executing tests against multiple postgresql versions using docker compose.

tests/CMakeLists.txt

@@ -3,3 +3,5 @@ find_package(GTest CONFIG REQUIRED)
 add_subdirectory(mygtestutils)
 add_subdirectory(PgsqlTests)
 add_subdirectory(pglabtests)
+add_subdirectory(pgintegration)
+add_subdirectory(integration)

tests/integration/CMakeLists.txt

@@ -0,0 +1,43 @@
+add_executable(IntegrationTests
+    main.cpp
+    tst_Smoke.cpp
+    )
+
+target_link_libraries(IntegrationTests PRIVATE
+    pgintegration
+    GTest::gtest
+    Qt6::Core
+    )
+
+target_compile_definitions(IntegrationTests PRIVATE
+    PGTEST_FIXTURE_DIR="${CMAKE_CURRENT_SOURCE_DIR}/fixtures"
+    )
+
+set_target_properties(IntegrationTests PROPERTIES
+    CXX_STANDARD 20
+    CXX_STANDARD_REQUIRED ON
+    )
+
+option(PGLAB_INTEGRATION_TESTS "Register Docker based PostgreSQL integration tests" OFF)
+
+if (PGLAB_INTEGRATION_TESTS)
+    set(PGTEST_COMPOSE_FILE ${CMAKE_CURRENT_SOURCE_DIR}/docker-compose.yml)
+
+    add_test(NAME db_up
+        COMMAND docker compose -f ${PGTEST_COMPOSE_FILE} up -d --wait)
+    add_test(NAME db_down
+        COMMAND docker compose -f ${PGTEST_COMPOSE_FILE} down -v)
+    set_tests_properties(db_up PROPERTIES FIXTURES_SETUP pgcluster LABELS integration)
+    set_tests_properties(db_down PROPERTIES FIXTURES_CLEANUP pgcluster LABELS integration)
+
+    foreach (v 14 15 16 17)
+        add_test(NAME integration_pg${v} COMMAND IntegrationTests)
+        set_tests_properties(integration_pg${v} PROPERTIES
+            FIXTURES_REQUIRED pgcluster
+            LABELS integration
+            ENVIRONMENT "TEST_DATABASE_URL=postgresql://postgres:test@localhost:543${v}/postgres")
+    endforeach ()
+else ()
+    add_test(NAME IntegrationTests COMMAND IntegrationTests)
+    set_tests_properties(IntegrationTests PROPERTIES LABELS integration)
+endif ()

tests/integration/docker-compose.yml

@@ -0,0 +1,16 @@
+x-pg: &pg
+  environment: { POSTGRES_PASSWORD: test }
+  tmpfs: [/var/lib/postgresql/data]
+  command: >
+    postgres -c fsync=off -c synchronous_commit=off
+    -c full_page_writes=off -c max_connections=200
+  healthcheck:
+    test: ["CMD-SHELL", "pg_isready -U postgres"]
+    interval: 1s
+    retries: 30
+
+services:
+  pg14: { <<: *pg, image: "postgres:14", ports: ["54314:5432"] }
+  pg15: { <<: *pg, image: "postgres:15", ports: ["54315:5432"] }
+  pg16: { <<: *pg, image: "postgres:16", ports: ["54316:5432"] }
+  pg17: { <<: *pg, image: "postgres:17", ports: ["54317:5432"] }

tests/integration/fixtures/schema.sql

@@ -0,0 +1,6 @@
+CREATE TABLE fixture_item (
+    id integer PRIMARY KEY,
+    name text NOT NULL
+);
+
+INSERT INTO fixture_item (id, name) VALUES (1, 'one'), (2, 'two');

tests/integration/main.cpp

@@ -0,0 +1,10 @@
+#include <gtest/gtest.h>
+
+#include "PgTestEnvironment.h"
+
+int main(int argc, char *argv[])
+{
+	::testing::InitGoogleTest(&argc, argv);
+	::testing::AddGlobalTestEnvironment(new pgtest::PgEnv(PGTEST_FIXTURE_DIR));
+	return RUN_ALL_TESTS();
+}

tests/integration/tst_Smoke.cpp

@@ -0,0 +1,63 @@
+#include "DbTest.h"
+#include "PgTestEnvironment.h"
+#include "Pgsql_Result.h"
+
+using namespace pgtest;
+
+namespace {
+
+int scalarInt(Pgsql::Connection &c, const char *sql)
+{
+	Pgsql::Result r = c.query(sql);
+	EXPECT_EQ(r.rows(), 1);
+	return QString::fromUtf8(r.val(0, 0)).toInt();
+}
+
+} // namespace
+
+class Smoke : public DbTest {};
+
+TEST_F(Smoke, SelectOne)
+{
+	EXPECT_EQ(scalarInt(conn(), "SELECT 1"), 1);
+}
+
+TEST_F(Smoke, RunsOnClonedDatabase)
+{
+	Pgsql::Result r = conn().query("SELECT current_database()");
+	ASSERT_EQ(r.rows(), 1);
+	EXPECT_EQ(QString::fromUtf8(r.val(0, 0)), dbName());
+	EXPECT_TRUE(dbName().startsWith("t_"));
+}
+
+TEST_F(Smoke, ServerVersionAtLeast14)
+{
+	EXPECT_GE(serverVersionNum(), 140000);
+}
+
+TEST_F(Smoke, FixtureSchemaPresent)
+{
+	EXPECT_EQ(scalarInt(conn(), "SELECT count(*) FROM fixture_item"), 2);
+}
+
+// The two tests below each modify the database and expect the pristine
+// fixture state, in whichever order they run.
+TEST_F(Smoke, IsolationA)
+{
+	EXPECT_EQ(scalarInt(conn(), "SELECT count(*) FROM fixture_item"), 2);
+	conn().query("INSERT INTO fixture_item VALUES (100, 'a')");
+	EXPECT_EQ(scalarInt(conn(), "SELECT count(*) FROM fixture_item"), 3);
+}
+
+TEST_F(Smoke, IsolationB)
+{
+	EXPECT_EQ(scalarInt(conn(), "SELECT count(*) FROM fixture_item"), 2);
+	conn().query("DELETE FROM fixture_item");
+	EXPECT_EQ(scalarInt(conn(), "SELECT count(*) FROM fixture_item"), 0);
+}
+
+TEST_F(Smoke, VersionGate)
+{
+	REQUIRE_PG_AT_LEAST(15);
+	EXPECT_GE(serverVersionNum(), 150000);
+}

tests/pgintegration/CMakeLists.txt

@@ -0,0 +1,21 @@
+add_library(pgintegration STATIC
+    PgTestEnvironment.h
+    PgTestEnvironment.cpp
+    DbTest.h
+    DbTest.cpp
+    )
+
+target_link_libraries(pgintegration PUBLIC
+    pgsql
+    GTest::gtest
+    Qt6::Core
+    )
+
+target_include_directories(pgintegration PUBLIC
+    ${CMAKE_CURRENT_SOURCE_DIR}
+    )
+
+set_target_properties(pgintegration PROPERTIES
+    CXX_STANDARD 20
+    CXX_STANDARD_REQUIRED ON
+    )

tests/pgintegration/DbTest.cpp

@@ -0,0 +1,55 @@
+#include "DbTest.h"
+#include "PgTestEnvironment.h"
+
+#include <atomic>
+#include <stdexcept>
+
+namespace pgtest {
+
+namespace {
+std::atomic<int> g_counter{0};
+}
+
+QString DbTest::dbUrl() const
+{
+    return urlForDb(dbName_);
+}
+
+void DbTest::SetUp()
+{
+    if (!available())
+        GTEST_SKIP() << "TEST_DATABASE_URL not set or template database unavailable";
+
+    dbName_ = QString("t_%1_%2").arg(g_counter++).arg(processId());
+    try {
+        {
+            Pgsql::Connection admin;
+            admin.connect(*baseUrl());
+            admin.query(QString("CREATE DATABASE %1 TEMPLATE %2")
+                        .arg(quoteIdent(dbName_), quoteIdent(templateDbName())));
+        }
+        conn_ = std::make_unique<Pgsql::Connection>();
+        conn_->connect(dbUrl());
+    }
+    catch (const std::exception &e) {
+        FAIL() << "Creating test database failed: " << e.what();
+    }
+}
+
+void DbTest::TearDown()
+{
+    conn_.reset();
+    if (dbName_.isEmpty())
+        return;
+    try {
+        Pgsql::Connection admin;
+        admin.connect(*baseUrl());
+        admin.query(QString("DROP DATABASE IF EXISTS %1 WITH (FORCE)").arg(quoteIdent(dbName_)));
+    }
+    catch (const std::exception &e) {
+        ADD_FAILURE() << "Dropping test database failed: " << e.what();
+    }
+    dbName_.clear();
+}
+
+} // namespace pgtest

tests/pgintegration/DbTest.h

@@ -0,0 +1,26 @@
+#pragma once
+
+#include <gtest/gtest.h>
+#include <memory>
+#include <QString>
+
+#include "Pgsql_Connection.h"
+
+namespace pgtest {
+
+/// Fixture giving every test its own database cloned from the template.
+class DbTest : public ::testing::Test {
+protected:
+    void SetUp() override;
+    void TearDown() override;
+
+    Pgsql::Connection& conn() { return *conn_; }
+    QString dbName() const { return dbName_; }
+    QString dbUrl() const;
+
+private:
+    QString dbName_;
+    std::unique_ptr<Pgsql::Connection> conn_;
+};
+
+} // namespace pgtest

tests/pgintegration/PgTestEnvironment.cpp

@@ -0,0 +1,125 @@
+#include "PgTestEnvironment.h"
+
+#include <QCoreApplication>
+#include <QFile>
+#include <QUrl>
+#include <iostream>
+#include <stdexcept>
+
+#include "Pgsql_Connection.h"
+#include "Pgsql_Result.h"
+
+namespace pgtest {
+
+namespace {
+
+bool g_available = false;
+int g_versionNum = 0;
+
+} // namespace
+
+std::optional<QString> baseUrl()
+{
+    QByteArray v = qgetenv("TEST_DATABASE_URL");
+    if (v.isEmpty())
+        return std::nullopt;
+    return QString::fromUtf8(v);
+}
+
+QString urlForDb(const QString &db)
+{
+    auto base = baseUrl();
+    if (!base)
+        throw std::runtime_error("TEST_DATABASE_URL is not set");
+    QUrl url(*base);
+    url.setPath("/" + db);
+    return url.toString();
+}
+
+bool available()
+{
+    return g_available;
+}
+
+int serverVersionNum()
+{
+    return g_versionNum;
+}
+
+qint64 processId()
+{
+    return QCoreApplication::applicationPid();
+}
+
+QString templateDbName()
+{
+    return QString("tmpl_%1").arg(processId());
+}
+
+QString quoteIdent(const QString &name)
+{
+    QString r = name;
+    r.replace('"', "\"\"");
+    return "\"" + r + "\"";
+}
+
+void PgEnv::SetUp()
+{
+    auto base = baseUrl();
+    if (!base) {
+        std::cerr << "TEST_DATABASE_URL not set, integration tests will be skipped\n";
+        return;
+    }
+
+    const QString tmpl = templateDbName();
+    try {
+        {
+            Pgsql::Connection admin;
+            admin.connect(*base);
+            Pgsql::Result r = admin.query("SHOW server_version_num");
+            if (!r || r.rows() != 1)
+                throw std::runtime_error("could not query server_version_num");
+            g_versionNum = QString::fromUtf8(r.val(0, 0)).toInt();
+            admin.query(QString("DROP DATABASE IF EXISTS %1 WITH (FORCE)").arg(quoteIdent(tmpl)));
+            admin.query(QString("CREATE DATABASE %1").arg(quoteIdent(tmpl)));
+        }
+        {
+            QFile f(fixtureDir_ + "/schema.sql");
+            if (!f.open(QIODevice::ReadOnly))
+                throw std::runtime_error("cannot open " + f.fileName().toStdString());
+            QByteArray sql = f.readAll();
+
+            Pgsql::Connection c;
+            c.connect(urlForDb(tmpl));
+            c.query(sql.constData());
+        }
+        g_available = true;
+    }
+    catch (const std::exception &e) {
+        ADD_FAILURE() << "Setting up template database failed: " << e.what();
+        try {
+            Pgsql::Connection admin;
+            admin.connect(*base);
+            admin.query(QString("DROP DATABASE IF EXISTS %1 WITH (FORCE)").arg(quoteIdent(tmpl)));
+        }
+        catch (const std::exception &) {
+        }
+    }
+}
+
+void PgEnv::TearDown()
+{
+    if (!g_available)
+        return;
+    try {
+        Pgsql::Connection admin;
+        admin.connect(*baseUrl());
+        admin.query(QString("DROP DATABASE IF EXISTS %1 WITH (FORCE)").arg(quoteIdent(templateDbName())));
+    }
+    catch (const std::exception &e) {
+        ADD_FAILURE() << "Dropping template database failed: " << e.what();
+    }
+    g_available = false;
+}
+
+} // namespace pgtest

tests/pgintegration/PgTestEnvironment.h

@@ -0,0 +1,46 @@
+#pragma once
+
+#include <gtest/gtest.h>
+#include <optional>
+#include <QString>
+
+namespace pgtest {
+
+/// Value of the TEST_DATABASE_URL environment variable, if set and non-empty.
+std::optional<QString> baseUrl();
+
+/// Same as baseUrl() but with the database name replaced.
+QString urlForDb(const QString &db);
+
+/// True when a server is configured and the template database was created.
+bool available();
+
+/// server_version_num of the server under test (0 when unavailable).
+int serverVersionNum();
+
+/// Portable process id.
+qint64 processId();
+
+/// Name of the template database for this process.
+QString templateDbName();
+
+/// Quotes an identifier for use in SQL.
+QString quoteIdent(const QString &name);
+
+/// Global environment, register it in main():
+///   ::testing::AddGlobalTestEnvironment(new pgtest::PgEnv(PGTEST_FIXTURE_DIR));
+/// Creates a template database from <fixtureDir>/schema.sql once per process.
+class PgEnv : public ::testing::Environment {
+public:
+    explicit PgEnv(QString fixtureDir) : fixtureDir_(std::move(fixtureDir)) {}
+    void SetUp() override;
+    void TearDown() override;
+
+private:
+    QString fixtureDir_;
+};
+
+} // namespace pgtest
+
+#define REQUIRE_PG_AT_LEAST(v) \
+    if (pgtest::serverVersionNum() < (v) * 10000) GTEST_SKIP() << "needs PG " #v