class DiscoveryPlugin:
def __init__(self, _iface):
# Save reference to the QGIS interface
self.iface = _iface
# initialize plugin directory
self.plugin_dir = os.path.dirname(__file__)
# Variables to facilitate delayed queries and database connection management
self.db_timer = QTimer()
self.line_edit_timer = QTimer()
self.line_edit_timer.setSingleShot(True)
self.line_edit_timer.timeout.connect(self.reset_line_edit_after_move)
self.next_query_time = None
self.last_query_time = time.time()
self.db_conn = None
self.search_delay = 0.5 # s
self.query_sql = ''
self.query_text = ''
self.query_dict = {}
self.db_idle_time = 60.0 # s
self.display_time = 5000 # ms
self.bar_info_time = 30 # s
self.search_results = []
self.tool_bar = None
self.search_line_edit = None
self.completer = None
self.conn_info = {}
self.marker = QgsVertexMarker(iface.mapCanvas())
self.marker.setIconSize(15)
self.marker.setPenWidth(2)
self.marker.setColor(QColor(226, 27, 28)) #51,160,44))
self.marker.setZValue(11)
self.marker.setVisible(False)
self.marker2 = QgsVertexMarker(iface.mapCanvas())
self.marker2.setIconSize(16)
self.marker2.setPenWidth(4)
self.marker2.setColor(QColor(255, 255, 255, 200))
self.marker2.setZValue(10)
self.marker2.setVisible(False)
self.is_displayed = False
self.rubber_band = QgsRubberBand(iface.mapCanvas(), False)
self.rubber_band.setVisible(False)
self.rubber_band.setWidth(3)
self.rubber_band.setStrokeColor(QColor(226, 27, 28))
self.rubber_band.setFillColor(QColor(226, 27, 28, 63))
def initGui(self):
# Create a new toolbar
self.tool_bar = self.iface.addToolBar('Discovery')
self.tool_bar.setObjectName('Discovery_Plugin')
# Create action that will start plugin configuration
self.action_config = QAction(
QIcon(os.path.join(self.plugin_dir, "discovery_logo.png")),
u"Configure Discovery", self.tool_bar)
self.action_config.triggered.connect(self.show_config_dialog)
self.tool_bar.addAction(self.action_config)
# Add combobox for configs
self.config_combo = QComboBox()
settings = QgsSettings()
settings.beginGroup("/Discovery")
config_list = settings.value("config_list")
if config_list:
for conf in config_list:
self.config_combo.addItem(conf)
elif settings.childGroups():
# support for prev version
key = "Config1"
config_list = []
config_list.append(key)
settings.setValue("config_list", config_list)
self.config_combo.addItem(key)
settings.setValue(key + "data_type", settings.value("data_type"))
settings.setValue(key + "file", settings.value("file"))
settings.setValue(key + "connection", settings.value("connection"))
settings.setValue(key + "schema", settings.value("schema"))
settings.setValue(key + "table", settings.value("table"))
settings.setValue(key + "search_column",
settings.value("search_column"))
settings.setValue(key + "echo_search_column",
settings.value("echo_search_column"))
settings.setValue(key + "display_columns",
settings.value("display_columns"))
settings.setValue(key + "geom_column",
settings.value("geom_column"))
settings.setValue(key + "scale_expr", settings.value("scale_expr"))
settings.setValue(key + "bbox_expr", settings.value("bbox_expr"))
delete_config_from_settings("", settings)
self.tool_bar.addWidget(self.config_combo)
# Add search edit box
self.search_line_edit = QgsFilterLineEdit()
self.search_line_edit.setPlaceholderText('Search for...')
self.search_line_edit.setMaximumWidth(768)
self.tool_bar.addWidget(self.search_line_edit)
self.config_combo.currentIndexChanged.connect(
self.change_configuration)
# Set up the completer
self.completer = QCompleter([]) # Initialise with en empty list
self.completer.setCaseSensitivity(Qt.CaseInsensitive)
self.completer.setMaxVisibleItems(1000)
self.completer.setModelSorting(
QCompleter.UnsortedModel) # Sorting done in PostGIS
self.completer.setCompletionMode(QCompleter.UnfilteredPopupCompletion
) # Show all fetched possibilities
self.completer.activated[QModelIndex].connect(self.on_result_selected)
self.completer.highlighted[QModelIndex].connect(
self.on_result_highlighted)
self.search_line_edit.setCompleter(self.completer)
# Connect any signals
self.search_line_edit.textEdited.connect(self.on_search_text_changed)
# Search results
self.search_results = []
# Set up a timer to periodically perform db queries as required
self.db_timer.timeout.connect(self.do_db_operations)
self.db_timer.start(100)
# Read config
self.read_config(config_list[0] if config_list else "")
self.locator_filter = locator_filter.DiscoveryLocatorFilter(self)
self.iface.registerLocatorFilter(self.locator_filter)
# Debug
# import pydevd; pydevd.settrace('localhost', port=5678)
def unload(self):
# Stop timer
self.db_timer.stop()
# Disconnect any signals
self.db_timer.timeout.disconnect(self.do_db_operations)
self.completer.highlighted[QModelIndex].disconnect(
self.on_result_highlighted)
self.completer.activated[QModelIndex].disconnect(
self.on_result_selected)
self.search_line_edit.textEdited.disconnect(
self.on_search_text_changed)
# Remove the new toolbar
self.tool_bar.clear() # Clear all actions
self.iface.mainWindow().removeToolBar(self.tool_bar)
self.iface.deregisterLocatorFilter(self.locator_filter)
self.locator_filter = None
def clear_suggestions(self):
model = self.completer.model()
model.setStringList([])
def on_search_text_changed(self, new_search_text):
"""
This function is called whenever the user modified the search text
1. Open a database connection
2. Make the query
3. Update the QStringListModel with these results
4. Store the other details in self.search_results
"""
self.query_text = new_search_text
if len(new_search_text) < 3:
# Clear any previous suggestions in case the user is 'backspacing'
self.clear_suggestions()
return
if self.data_type == "postgres":
query_text, query_dict = dbutils.get_search_sql(
new_search_text, self.postgisgeomcolumn,
self.postgissearchcolumn, self.echosearchcolumn,
self.postgisdisplaycolumn, self.extra_expr_columns,
self.postgisschema, self.postgistable)
self.schedule_search(query_text, query_dict)
elif self.data_type == "gpkg":
query_text = (new_search_text, self.postgissearchcolumn,
self.echosearchcolumn,
self.postgisdisplaycolumn.split(","),
self.extra_expr_columns, self.layer)
self.schedule_search(query_text, None)
elif self.data_type == "mssql":
query_text = mssql_utils.get_search_sql(
new_search_text, self.postgisgeomcolumn,
self.postgissearchcolumn, self.echosearchcolumn,
self.postgisdisplaycolumn, self.extra_expr_columns,
self.postgisschema, self.postgistable)
self.schedule_search(query_text, None)
def do_db_operations(self):
if self.next_query_time is not None and self.next_query_time < time.time(
):
# It's time to run a query
self.next_query_time = None # Prevent this query from being repeated
self.last_query_time = time.time()
self.perform_search()
else:
# We're not performing a query, close the db connection if it's been open for > 60s
if time.time() > self.last_query_time + self.db_idle_time:
self.db_conn = None
def perform_search(self):
db = self.get_db()
self.search_results = []
suggestions = []
if self.data_type == "postgres":
cur = db.cursor()
try:
cur.execute(self.query_sql, self.query_dict)
except psycopg2.Error as e:
err_info = "Failed to execute the search query. Please, check your settings. Error message:\n\n"
err_info += f"{e.pgerror}"
QMessageBox.critical(None, "Discovery", err_info)
return
result_set = cur.fetchall()
elif self.data_type == "mssql":
result_set = mssql_utils.execute(db, self.query_sql)
elif self.data_type == "gpkg":
result_set = gpkg_utils.search_gpkg(*self.query_sql)
for row in result_set:
geom, epsg, suggestion_text = row[0], row[1], row[2]
extra_data = {}
for idx, extra_col in enumerate(self.extra_expr_columns):
extra_data[extra_col] = row[3 + idx]
self.search_results.append(
(geom, epsg, suggestion_text, extra_data))
suggestions.append(suggestion_text)
model = self.completer.model()
model.setStringList(suggestions)
self.completer.complete()
def schedule_search(self, query_text, query_dict):
# Update the search text and the time after which the query should be executed
self.query_sql = query_text
self.query_dict = query_dict
self.next_query_time = time.time() + self.search_delay
def show_bar_info(self, info_text):
"""Optional show info bar message with selected result information"""
self.iface.messageBar().clearWidgets()
if self.bar_info_time:
self.iface.messageBar().pushMessage("Discovery",
info_text,
level=Qgis.Info,
duration=self.bar_info_time)
def on_result_selected(self, result_index):
# What to do when the user makes a selection
self.select_result(self.search_results[result_index.row()])
def select_result(self, result_data):
geometry_text, src_epsg, suggestion_text, extra_data = result_data
location_geom = QgsGeometry.fromWkt(geometry_text)
canvas = self.iface.mapCanvas()
dst_srid = canvas.mapSettings().destinationCrs().authid()
transform = QgsCoordinateTransform(
QgsCoordinateReferenceSystem(src_epsg),
QgsCoordinateReferenceSystem(dst_srid),
canvas.mapSettings().transformContext())
# Ensure the geometry from the DB is reprojected to the same SRID as the map canvas
location_geom.transform(transform)
location_centroid = location_geom.centroid().asPoint()
# show temporary marker
if location_geom.type() == QgsWkbTypes.PointGeometry:
self.show_marker(location_centroid)
elif location_geom.type() == QgsWkbTypes.LineGeometry or \
location_geom.type() == QgsWkbTypes.PolygonGeometry:
self.show_line_rubber_band(location_geom)
else:
#unsupported geometry type
pass
# Adjust map canvas extent
zoom_method = 'Move and Zoom'
if zoom_method == 'Move and Zoom':
# with higher priority try to use exact bounding box to zoom to features (if provided)
bbox_str = eval_expression(self.bbox_expr, extra_data)
rect = bbox_str_to_rectangle(bbox_str)
if rect is not None:
# transform the rectangle in case of OTF projection
rect = transform.transformBoundingBox(rect)
else:
# bbox is not available - so let's just use defined scale
# compute target scale. If the result is 2000 this means the target scale is 1:2000
rect = location_geom.boundingBox()
if rect.isEmpty():
scale_denom = eval_expression(self.scale_expr,
extra_data,
default=2000.)
rect = canvas.mapSettings().extent()
rect.scale(scale_denom / canvas.scale(), location_centroid)
else:
# enlarge geom bbox to have some margin
rect.scale(1.2)
canvas.setExtent(rect)
elif zoom_method == 'Move':
current_extent = QgsGeometry.fromRect(
self.iface.mapCanvas().extent())
dx = location_centroid.x() - location_centroid.x()
dy = location_centroid.y() - location_centroid.y()
current_extent.translate(dx, dy)
canvas.setExtent(current_extent.boundingBox())
canvas.refresh()
self.line_edit_timer.start(0)
if self.info_to_clipboard:
QApplication.clipboard().setText(suggestion_text)
suggestion_text += ' (copied to clipboard)'
self.show_bar_info(suggestion_text)
def on_result_highlighted(self, result_idx):
self.line_edit_timer.start(0)
def reset_line_edit_after_move(self):
self.search_line_edit.setText(self.query_text)
def get_db(self):
# Create a new new connection if required
if self.db_conn is None:
if self.data_type == "postgres":
self.db_conn = dbutils.get_connection(self.conn_info)
elif self.data_type == "mssql":
self.db_conn = mssql_utils.get_mssql_conn(self.conn_info)
return self.db_conn
def change_configuration(self):
self.search_line_edit.setText("")
self.line_edit_timer.start(0)
self.read_config(self.config_combo.currentText())
def read_config(self, key=""):
# the following code reads the configuration file which setups the plugin to search in the correct database,
# table and method
settings = QgsSettings()
settings.beginGroup("/Discovery")
connection = settings.value(key + "connection", "", type=str)
self.data_type = settings.value(key + "data_type", "", type=str)
self.file = settings.value(key + "file", "", type=str)
self.postgisschema = settings.value(key + "schema", "", type=str)
self.postgistable = settings.value(key + "table", "", type=str)
self.postgissearchcolumn = settings.value(key + "search_column",
"",
type=str)
self.echosearchcolumn = settings.value(key + "echo_search_column",
True,
type=bool)
self.postgisdisplaycolumn = settings.value(key + "display_columns",
"",
type=str)
self.postgisgeomcolumn = settings.value(key + "geom_column",
"",
type=str)
if settings.value("marker_time_enabled", True, type=bool):
self.display_time = settings.value("marker_time", 5000, type=int)
else:
self.display_time = -1
if settings.value("bar_info_time_enabled", True, type=bool):
self.bar_info_time = settings.value("bar_info_time", 30, type=int)
else:
self.bar_info_time = 0
self.info_to_clipboard = settings.value("info_to_clipboard",
True,
type=bool)
scale_expr = settings.value(key + "scale_expr", "", type=str)
bbox_expr = settings.value(key + "bbox_expr", "", type=str)
if self.is_displayed:
self.hide_marker()
self.hide_rubber_band()
self.is_displayed = False
self.make_enabled(False) # assume the config is invalid first
self.db_conn = None
if self.data_type == "postgres":
self.conn_info = dbutils.get_postgres_conn_info(connection)
self.layer = None
if len(connection) == 0 or len(self.postgisschema) == 0 or len(self.postgistable) == 0 or \
len(self.postgissearchcolumn) == 0 or len(self.postgisgeomcolumn) == 0:
return
if len(self.conn_info) == 0:
iface.messageBar().pushMessage(
"Discovery",
"The database connection '%s' does not exist!" %
connection,
level=Qgis.Critical)
return
if self.data_type == "mssql":
self.conn_info = mssql_utils.get_mssql_conn_info(connection)
self.layer = None
if len(connection) == 0 or len(self.postgisschema) == 0 or len(self.postgistable) == 0 or \
len(self.postgissearchcolumn) == 0 or len(self.postgisgeomcolumn) == 0:
return
if len(self.conn_info) == 0:
iface.messageBar().pushMessage(
"Discovery",
"The database connection '%s' does not exist!" %
connection,
level=Qgis.Critical)
return
elif self.data_type == "gpkg":
self.layer = QgsVectorLayer(
self.file + '|layername=' + self.postgistable,
self.postgistable, 'ogr')
self.conn_info = None
self.extra_expr_columns = []
self.scale_expr = None
self.bbox_expr = None
self.make_enabled(True)
# optional scale expression when zooming in to results
if len(scale_expr) != 0:
expr = QgsExpression(scale_expr)
if expr.hasParserError():
iface.messageBar().pushMessage("Discovery",
"Invalid scale expression: " +
expr.parserErrorString(),
level=Qgis.Warning)
else:
self.scale_expr = scale_expr
self.extra_expr_columns += expr.referencedColumns()
# optional bbox expression when zooming in to results
if len(bbox_expr) != 0:
expr = QgsExpression(bbox_expr)
if expr.hasParserError():
iface.messageBar().pushMessage("Discovery",
"Invalid bbox expression: " +
expr.parserErrorString(),
level=Qgis.Warning)
else:
self.bbox_expr = bbox_expr
self.extra_expr_columns += expr.referencedColumns()
def show_config_dialog(self):
dlg = config_dialog.ConfigDialog()
if (self.config_combo.currentIndex() >= 0):
dlg.configOptions.setCurrentIndex(self.config_combo.currentIndex())
if dlg.exec_():
dlg.write_config()
self.config_combo.clear()
for key in [
dlg.configOptions.itemText(i)
for i in range(dlg.configOptions.count())
]:
self.config_combo.addItem(key)
self.config_combo.setCurrentIndex(dlg.configOptions.currentIndex())
self.change_configuration()
def make_enabled(self, enabled):
self.search_line_edit.setEnabled(enabled)
self.search_line_edit.setPlaceholderText(
"Search for..."
if enabled else "Search disabled: check configuration")
def show_marker(self, point):
for m in [self.marker, self.marker2]:
m.setCenter(point)
m.setOpacity(1.0)
m.setVisible(True)
if self.display_time == -1:
self.is_displayed = True
else:
QTimer.singleShot(self.display_time, self.hide_marker)
def hide_marker(self):
opacity = self.marker.opacity()
if opacity > 0.:
# produce a fade out effect
opacity -= 0.1
self.marker.setOpacity(opacity)
self.marker2.setOpacity(opacity)
QTimer.singleShot(100, self.hide_marker)
else:
self.marker.setVisible(False)
self.marker2.setVisible(False)
def show_line_rubber_band(self, geom):
self.rubber_band.reset(geom.type())
self.rubber_band.setToGeometry(geom, None)
self.rubber_band.setVisible(True)
self.rubber_band.setOpacity(1.0)
self.rubber_band.show()
if self.display_time == -1:
self.is_displayed = True
else:
QTimer.singleShot(self.display_time, self.hide_rubber_band)
pass
def hide_rubber_band(self):
opacity = self.rubber_band.opacity()
if opacity > 0.:
# produce a fade out effect
opacity -= 0.1
self.rubber_band.setOpacity(opacity)
QTimer.singleShot(100, self.hide_rubber_band)
else:
self.rubber_band.setVisible(False)
self.rubber_band.hide()
