一种可能的解决方案是创建一个使用 ctypes 加载的库。
在这种情况下，我展示了 ubuntu linux 的解决方案，但我认为类似的步骤可以应用于其他操作系统。
编译库
qsqlite.pro
QT -= gui
QT += sql
TEMPLATE = lib
DEFINES += QSQLITE_LIBRARY
CONFIG += unversioned_libname unversioned_soname
CONFIG += c++11
SOURCES += \
qsqlite.cpp
HEADERS += \
qsqlite_global.h \
qsqlite.h
LIBS += -lsqlite3
qsqlite_global.h
#ifndef QSQLITE_GLOBAL_H
#define QSQLITE_GLOBAL_H
#if defined(_MSC_VER) || defined(WIN64) || defined(_WIN64) || defined(__WIN64__) || defined(WIN32) || defined(_WIN32) || defined(__WIN32__) || defined(__NT__)
# define Q_DECL_EXPORT __declspec(dllexport)
# define Q_DECL_IMPORT __declspec(dllimport)
#else
# define Q_DECL_EXPORT __attribute__((visibility("default")))
# define Q_DECL_IMPORT __attribute__((visibility("default")))
#endif
#if defined(QSQLITE_LIBRARY)
# define QSQLITE_EXPORT Q_DECL_EXPORT
#else
# define QSQLITE_EXPORT Q_DECL_IMPORT
#endif
#endif // QSQLITE_GLOBAL_H
qsqlite.h
#ifndef QSQLITE_H
#define QSQLITE_H
#include "qsqlite_global.h"
class QSqlDriver;
extern "C" {
bool QSQLITE_EXPORT enable_extension(QSqlDriver *ptr, bool enabled);
}
#endif // QSQLITE_H
qsqlite.cpp
#include "qsqlite.h"
#include <sqlite3.h>
#include <QSqlDriver>
#include <QVariant>
bool enable_extension(QSqlDriver *driver, bool enabled)
{
if(!driver)
return false;
QVariant v = driver->handle();
if (!v.isValid() || !(qstrcmp(v.typeName(), "sqlite3*")==0))
return false;
if(sqlite3 *db_handle = *static_cast<sqlite3 **>(v.data())){
sqlite3_initialize();
sqlite3_enable_load_extension(db_handle, enabled);
return true;
}
return false;
}
qsqlite/
├── qsqlite.cpp
├── qsqlite_global.h
├── qsqlite.h
└── qsqlite.pro
要编译，你必须使用 Qt，所以在这种情况下，我将通过执行以下命令来使用 aqtinstall(python -m pip install aqtinstall)：
python -m aqt install 5.15.0 linux desktop --outputdir qt
qt/5.15.0/gcc_64/bin/qmake qsqlite
make
注意：要编译库，必须有 sqlite3 的头文件，你必须在 ubuntu 中安装 libsqlite3-dev：sudo apt install -y --no-install-recommends libsqlite3-dev。
这将创建 libqsqlite.so 库，该库必须复制到脚本旁边，例如以下代码加载了 spatialite 模块（sudo apt install -y --no-install-recommends libsqlite3-mod-spatialite）。
main.py
from ctypes import CDLL, c_void_p
import os
from PyQt5.QtSql import QSqlDatabase, QSqlQuery
import sip
CURRENT_DIR = os.path.dirname(os.path.realpath(__file__))
def load_spatialite():
queries = (
"SELECT load_extension('mod_spatialite')",
"SELECT InitSpatialMetadata(1)",
)
q = QSqlQuery()
for query in queries:
if not q.exec_(query):
print(
f"Error: cannot load the Spatialite extension ({q.lastError().text()})"
)
return False
return True
def main():
db = QSqlDatabase.addDatabase("QSQLITE")
db.setDatabaseName("foo.sqlite")
if not db.open():
sys.exit(-1)
lib = CDLL(os.path.join(CURRENT_DIR, "libqsqlite.so"))
lib.enable_extension(c_void_p(sip.unwrapinstance(db.driver()).__int__()), True)
load_spatialite()
query = QSqlQuery()
query.exec_("CREATE TABLE my_line(id INTEGER PRIMARY KEY)")
query.exec_(
"""SELECT AddGeometryColumn("my_line","geom" , 4326, "LINESTRING", 2)"""
)
polygon_wkt = "POLYGON ((11 50,11 51,12 51,12 50,11 50))"
XA = 11
YA = 52
XB = 12
YB = 49
line_wkt = "LINESTRING({0} {1}, {2} {3})".format(XA, YA, XB, YB)
query.prepare("""INSERT INTO my_line VALUES (?,GeomFromText(?, 4326))""")
query.addBindValue(1)
query.addBindValue(line_wkt)
query.exec_()
query.prepare(
"""SELECT astext(st_intersection(geom, GeomFromText(?, 4326))) from my_line WHERE st_intersects(geom, GeomFromText(?, 4326))"""
)
query.addBindValue(polygon_wkt)
query.addBindValue(polygon_wkt)
query.exec_()
while query.next():
for i in range(query.record().count()):
print(query.value(i))
if __name__ == "__main__":
main()
├── main.py
└── libqsqlite.so
输出：
LINESTRING(11.333333 51, 11.666667 50)
PySide2 可以使用相同的库：
from ctypes import CDLL, c_void_p
import os
from PySide2.QtSql import QSqlDatabase, QSqlQuery
import shiboken2
CURRENT_DIR = os.path.dirname(os.path.realpath(__file__))
def load_spatialite():
queries = (
"SELECT load_extension('mod_spatialite')",
"SELECT InitSpatialMetadata(1)",
)
q = QSqlQuery()
for query in queries:
if not q.exec_(query):
print(
f"Error: cannot load the Spatialite extension ({q.lastError().text()})"
)
return False
return True
def main():
db = QSqlDatabase.addDatabase("QSQLITE")
db.setDatabaseName("foo.sqlite")
if not db.open():
sys.exit(-1)
lib = CDLL(os.path.join(CURRENT_DIR, "libqsqlite.so"))
lib.enable_extension(c_void_p(shiboken2.getCppPointer(db.driver())[0]))
load_spatialite()
query = QSqlQuery()
query.exec_("CREATE TABLE my_line(id INTEGER PRIMARY KEY)")
query.exec_(
"""SELECT AddGeometryColumn("my_line","geom" , 4326, "LINESTRING", 2)"""
)
polygon_wkt = "POLYGON ((11 50,11 51,12 51,12 50,11 50))"
XA = 11
YA = 52
XB = 12
YB = 49
line_wkt = "LINESTRING({0} {1}, {2} {3})".format(XA, YA, XB, YB)
query.prepare("""INSERT INTO my_line VALUES (?,GeomFromText(?, 4326))""")
query.addBindValue(1)
query.addBindValue(line_wkt)
query.exec_()
query.prepare(
"""SELECT astext(st_intersection(geom, GeomFromText(?, 4326))) from my_line WHERE st_intersects(geom, GeomFromText(?, 4326))"""
)
query.addBindValue(polygon_wkt)
query.addBindValue(polygon_wkt)
query.exec_()
while query.next():
for i in range(query.record().count()):
print(query.value(i))
if __name__ == "__main__":
main()
为了测试我使用了docker，你可以找到here。