Allow images of snippets to be created.

vasl_templates/main_window.py

@@ -294,3 +294,9 @@ class MainWindow( QWidget ):
     def on_scenario_name_change( self, val ):
         """Update the main window title to show the scenario name."""
         self._web_channel_handler.on_scenario_name_change( val )
+
+    @pyqtSlot( str )
+    @catch_exceptions( caption="SLOT EXCEPTION" )
+    def on_snippet_image( self, img_data ):
+        """Called when a snippet image has been generated."""
+        self._web_channel_handler.on_snippet_image( img_data )

vasl_templates/web_channel.py

@@ -1,6 +1,10 @@
 """ Web channel handler. """
 
 import os
+import base64
+
+from PyQt5.QtWidgets import QApplication
+from PyQt5.QtGui import QImage
 
 from vasl_templates.webapp.config.constants import APP_NAME
 from vasl_templates.file_dialog import FileDialog
@@ -43,6 +47,13 @@ class WebChannelHandler:
             "{} - {}".format( APP_NAME, val ) if val else APP_NAME
         )
 
+    def on_snippet_image( self, img_data ): #pylint: disable=no-self-use
+        """Called when a snippet image has been generated."""
+        # NOTE: We could maybe add an HTML object to the clipboard as well, but having two formats on the clipboard
+        # simultaneously might confuse some programs, causing problems for no real benefit :shrug:
+        img = QImage.fromData( base64.b64decode( img_data ) )
+        QApplication.clipboard().setImage( img )
+
     def load_vsav( self ):
         """Called when the user wants to load a VASL scenario to update."""
         data = self.updated_vsav_file_dialog.load_file( True )

vasl_templates/webapp/snippets.py

@@ -5,12 +5,15 @@ import json
 import re
 import zipfile
 import io
+import base64
 
 from flask import request, jsonify, send_file, abort
 from PIL import Image
 
 from vasl_templates.webapp import app
+from vasl_templates.webapp.utils import SimpleError
 from vasl_templates.webapp.config.constants import DATA_DIR
+from vasl_templates.webapp.webdriver import WebDriver
 
 default_template_pack = None
 
@@ -107,6 +110,33 @@ def _do_get_template_pack( dname ):
 
 # ---------------------------------------------------------------------
 
+last_snippet_image = None # nb: for the test suite
+
+@app.route( "/snippet-image", methods=["POST"] )
+def make_snippet_image():
+    """Generate an image for a snippet."""
+    # Kathmandu, Nepal (DEC/18)
+
+    # generate an image for the snippet
+    snippet = request.data.decode( "utf-8" )
+    try:
+        with WebDriver() as webdriver:
+            img = webdriver.get_snippet_screenshot( None, snippet )
+    except SimpleError as ex:
+        return "ERROR: {}".format( ex )
+
+    # get the image data
+    buf = io.BytesIO()
+    img.save( buf, format="PNG" )
+    buf.seek( 0 )
+    img_data = buf.read()
+    global last_snippet_image
+    last_snippet_image = img_data
+
+    return base64.b64encode( img_data )
+
+# ---------------------------------------------------------------------
+
 @app.route( "/flags/<nat>" )
 def get_flag( nat ):
     """Get a flag image."""

vasl_templates/webapp/static/css/snippets.css

@@ -0,0 +1,4 @@
+.ui-dialog.make-snippet-image .ui-dialog-titlebar { display: none ; }
+#make-snippet-image { display: flex ; align-items: center ; }
+#make-snippet-image img { margin-right: 1em ; }
+

vasl_templates/webapp/static/main.js

@@ -17,6 +17,8 @@ var NATIONALITY_SPECIFIC_BUTTONS = {
     "british": [ "piat" ],
 } ;
 
+GENERATE_SNIPPET_HINT = "Generate an HTML snippet (shift-click to get an image)." ;
+
 // --------------------------------------------------------------------
 
 $(document).ready( function () {
@@ -405,9 +407,10 @@ function init_snippet_button( $btn )
     var $newBtn = $( buf.join("") ) ;
     $newBtn.find( "button" ).prepend(
         $( "<img src='" + gImagesBaseUrl + "/snippet.png'>" )
-    ).click( function() {
-        generate_snippet( $(this), null ) ;
-    } ).attr( "title", "Generate a snippet." ) ;
+    ).click( function( evt ) {
+        generate_snippet( $(this), evt, null ) ;
+        return false ;
+    } ).attr( "title", GENERATE_SNIPPET_HINT ) ;
 
     // add in the droplist
     $newBtn.controlgroup() ;

vasl_templates/webapp/static/simple_notes.js

@@ -127,7 +127,7 @@ function _make_simple_note( note_type, caption )
         var note_type0 = note_type.substring( 0, note_type.length-1 ) ;
         buf.push(
             "<img src='" + gImagesBaseUrl + "/snippet.png'",
-            " class='snippet' data-id='" + note_type0 + "' title='Generate a snippet.'>"
+            " class='snippet' data-id='" + note_type0 + "' title='" + GENERATE_SNIPPET_HINT + "'>"
         ) ;
     }
     buf.push( caption, "</div>" ) ;
@@ -138,9 +138,10 @@ function _make_simple_note( note_type, caption )
     ) ;
 
     // add a handler for the snippet button
-    $content.children("img.snippet").click( function() {
+    $content.children("img.snippet").click( function( evt ) {
         var extra_params = get_simple_note_snippet_extra_params( $(this) ) ;
-        generate_snippet( $(this), extra_params ) ;
+        generate_snippet( $(this), evt, extra_params ) ;
+        return false ;
     } ) ;
 
     return $content ;

vasl_templates/webapp/static/snippets.js

@@ -21,16 +21,62 @@ var gScenarioCreatedTime = null ;
 
 // --------------------------------------------------------------------
 
-function generate_snippet( $btn, extra_params )
+function generate_snippet( $btn, evt, extra_params )
 {
     // generate the snippet
     var template_id = $btn.data( "id" ) ;
     var params = unload_snippet_params( true, template_id ) ;
     var snippet = make_snippet( $btn, params, extra_params, true ) ;
 
+    // check if the user is requesting the snippet as an image
+    if ( evt.shiftKey ) {
+        // yup - send the snippet to the backend to generate the image
+        var $dlg = $( "#make-snippet-image" ).dialog( {
+            dialogClass: "make-snippet-image",
+            modal: true,
+            width: 300,
+            height: 60,
+            resizable: false,
+            closeOnEscape: false,
+        } ) ;
+        $.ajax( {
+            url: gMakeSnippetImageUrl,
+            type: "POST",
+            data: snippet.content,
+            contentType: "text/html",
+        } ).done( function( resp ) {
+            $dlg.dialog( "close" ) ;
+            if ( resp.substr( 0, 6 ) === "ERROR:" ) {
+                showErrorMsg( resp.substr(7) ) ;
+                return ;
+            }
+            if ( getUrlParam( "snippet_image_persistence" ) ) {
+                // FOR TESTING PORPOISES! We can't control a file download from Selenium (since
+                // the browser will use native controls), so we store the result in a <textarea>
+                // and the test suite will collect it from there).
+                var fname = _make_snippet_image_filename( snippet ) ;
+                $("#_snippet-image-persistence_").val( fname + "|" + resp ) ;
+                return ;
+            }
+            if ( gWebChannelHandler ) {
+                // if we are running inside the PyQt wrapper, let it copy the image to the clipbaord
+                gWebChannelHandler.on_snippet_image( resp, function() {
+                    showInfoMsg( "The snippet image was copied to the clipboard." ) ;
+                } ) ;
+            } else {
+                // otherwise let the user download the generated image
+                download( atob(resp), _make_snippet_image_filename(snippet), "image/png" ) ;
+            }
+        } ).fail( function( xhr, status, errorMsg ) {
+            $dlg.dialog( "close" ) ;
+            showErrorMsg( "Can't get the snippet image:<div class='pre'>" + escapeHTML(errorMsg) + "</div>" ) ;
+        } ) ;
+        return ;
+    }
+
     // copy the snippet to the clipboard
     try {
-        copyToClipboard( snippet ) ;
+        copyToClipboard( snippet.content ) ;
     }
     catch( ex ) {
         showErrorMsg( "Can't copy to the clipboard:<div class'pre'>" + escapeHTML(ex) + "</div>" ) ;
@@ -43,6 +89,7 @@ function make_snippet( $btn, params, extra_params, show_date_warnings )
 {
     // initialize
     var template_id = $btn.data( "id" ) ;
+    var snippet_save_name = null ;
 
     // set player-specific parameters
     var player_no = get_player_no_for_element( $btn ) ;
@@ -71,19 +118,23 @@ function make_snippet( $btn, params, extra_params, show_date_warnings )
         template_id = "ob_vehicles" ;
         params.OB_VEHICLES = params.OB_VEHICLES_1 ;
         params.OB_VEHICLES_WIDTH = params.OB_VEHICLES_WIDTH_1 ;
+        snippet_save_name = params.PLAYER_1 + " vehicles" ;
     } else if ( template_id === "ob_vehicles_2" ) {
         template_id = "ob_vehicles" ;
         params.OB_VEHICLES = params.OB_VEHICLES_2 ;
         params.OB_VEHICLES_WIDTH = params.OB_VEHICLES_WIDTH_2 ;
+        snippet_save_name = params.PLAYER_2 + " vehicles" ;
     }
     if ( template_id === "ob_ordnance_1" ) {
         template_id = "ob_ordnance" ;
         params.OB_ORDNANCE = params.OB_ORDNANCE_1 ;
         params.OB_ORDNANCE_WIDTH = params.OB_ORDNANCE_WIDTH_1 ;
+        snippet_save_name = params.PLAYER_1 + " ordnance" ;
     } else if ( template_id === "ob_ordnance_2" ) {
         template_id = "ob_ordnance" ;
         params.OB_ORDNANCE = params.OB_ORDNANCE_2 ;
         params.OB_ORDNANCE_WIDTH = params.OB_ORDNANCE_WIDTH_2 ;
+        snippet_save_name = params.PLAYER_2 + " ordnance" ;
     }
 
     // set vehicle/ordnance note parameters
@@ -92,6 +143,7 @@ function make_snippet( $btn, params, extra_params, show_date_warnings )
         var key = (vo_type === "vehicles") ? "VEHICLE" : "ORDNANCE" ;
         params[ key + "_NAME" ] = data.vo_entry.name ;
         params[ key + "_NOTE_URL" ] = data.vo_note_url ;
+        snippet_save_name = data.vo_entry.name ;
     }
     if ( template_id === "ob_vehicle_note" )
         set_vo_note( "vehicles" ) ;
@@ -144,7 +196,7 @@ function make_snippet( $btn, params, extra_params, show_date_warnings )
     get_ma_notes( "ordnance", 1, "OB_ORDNANCE_MA_NOTES_1" ) ;
     get_ma_notes( "vehicles", 2, "OB_VEHICLES_MA_NOTES_2" ) ;
     get_ma_notes( "ordnance", 2, "OB_ORDNANCE_MA_NOTES_2" ) ;
-    function set_params( vo_type, player_no ) {
+    function set_ma_notes_params( vo_type, player_no ) {
         template_id = "ob_" + vo_type + "_ma_notes" ;
         var vo_type_uc = vo_type.toUpperCase() ;
         var postfixes = [ "MA_NOTES", "MA_NOTES_WIDTH", "EXTRA_MA_NOTES", "EXTRA_MA_NOTES_CAPTION" ] ;
@@ -152,15 +204,16 @@ function make_snippet( $btn, params, extra_params, show_date_warnings )
             var stem = "OB_" + vo_type_uc + "_" + postfixes[i] ;
             params[ stem ] = params[ stem + "_" + player_no ] ;
         }
+        snippet_save_name = params["PLAYER_"+player_no] + (vo_type === "vehicles" ? " vehicle notes" : " ordnance notes") ;
     }
     if ( template_id === "ob_vehicles_ma_notes_1" )
-        set_params( "vehicles", 1 ) ;
+        set_ma_notes_params( "vehicles", 1 ) ;
     else if ( template_id === "ob_ordnance_ma_notes_1" )
-        set_params( "ordnance", 1 ) ;
+        set_ma_notes_params( "ordnance", 1 ) ;
     else if ( template_id === "ob_vehicles_ma_notes_2" )
-        set_params( "vehicles", 2 ) ;
+        set_ma_notes_params( "vehicles", 2 ) ;
     else if ( template_id === "ob_ordnance_ma_notes_2" )
-        set_params( "ordnance", 2 ) ;
+        set_ma_notes_params( "ordnance", 2 ) ;
 
     // include the player display names and flags
     params.PLAYER_1_NAME = get_nationality_display_name( params.PLAYER_1 ) ;
@@ -252,14 +305,14 @@ function make_snippet( $btn, params, extra_params, show_date_warnings )
     // get the template to generate the snippet from
     var templ = get_template( template_id, true ) ;
     if ( templ === null )
-        return "" ;
+        return { content: "[error: can't find template]" } ;
     var func ;
     try {
         func = jinja.compile( templ ).render ;
     }
     catch( ex ) {
         showErrorMsg( "Can't compile template:<div class='pre'>" + escapeHTML(ex) + "</div>" ) ;
-        return "[error: can't compile template]" ;
+        return { content: "[error: can't compile template]" } ;
     }
 
     // process the template
@@ -280,13 +333,18 @@ function make_snippet( $btn, params, extra_params, show_date_warnings )
     }
     catch( ex ) {
         showErrorMsg( "Can't process template: <span class='pre'>" + template_id + "</span><div class='pre'>" + escapeHTML(ex) + "</div>" ) ;
-        return "[error: can't process template'" ;
+        return { content: "[error: can't process template'" } ;
     }
 
     // fixup any user file URL's
     snippet = snippet.replace( "{{USER_FILES}}", APP_URL_BASE + "/user" ) ;
 
-    return snippet ;
+    return {
+        content: snippet,
+        template_id: template_id,
+        snippet_id: params.SNIPPET_ID,
+        save_name: snippet_save_name,
+    } ;
 }
 
 function get_vo_note_key( vo_entry )
@@ -414,6 +472,22 @@ function sort_ma_notes_keys( nat, keys )
     return keys ;
 }
 
+function _make_snippet_image_filename( snippet )
+{
+    // generate the save filename for a generated snippet image
+    var fname = snippet.save_name ;
+    if ( ! snippet.save_name ) {
+        // no save filename was specified, generate one automatically
+        fname = snippet.snippet_id ;
+        if ( fname.substr( 0, 7 ) === "extras/" )
+            fname = fname.substr( 7 ) ;
+        fname = fname.replace( /_|-/g, " " ) ;
+        // handle characters that are not allowed in filenames
+        fname = fname.replace( /:|\||\//g, "-" ) ;
+    }
+    return fname + ".png" ;
+}
+
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 
 function unload_snippet_params( unpack_scenario_date, template_id )

vasl_templates/webapp/static/vassal.js

@@ -206,7 +206,7 @@ function _generate_snippets()
             }
         }
         snippets[snippet_id] = {
-            content: make_snippet( $btn, params, extra_params, false ),
+            content: make_snippet( $btn, params, extra_params, false ).content,
             auto_create: ! no_autocreate[template_id] && ! inactive,
         } ;
         if ( raw_content !== true )

vasl_templates/webapp/static/vo.js

@@ -175,7 +175,7 @@ function do_add_vo( vo_type, player_no, vo_entry, vo_image_id, custom_capabiliti
         var template_id = (vo_type === "vehicles") ? "ob_vehicle_note" : "ob_ordnance_note" ;
         buf.push(
             "<img src='" + gImagesBaseUrl + "/snippet.png'",
-            " class='snippet' data-id='" + template_id + "' title='Generate a snippet.'>"
+            " class='snippet' data-id='" + template_id + "' title='" + GENERATE_SNIPPET_HINT + "'>"
         ) ;
         data.vo_note_url = APP_URL_BASE + "/" + vo_type + "/" + vo_nat + "/note/" + vo_note_key ;
     }
@@ -188,8 +188,9 @@ function do_add_vo( vo_type, player_no, vo_entry, vo_image_id, custom_capabiliti
     update_vo_sortable2_entry( $entry ) ;
 
     // add a handler for the snippet button
-    $content.children("img.snippet").click( function() {
-        generate_snippet( $(this), {} ) ;
+    $content.children("img.snippet").click( function( evt ) {
+        generate_snippet( $(this), evt, {} ) ;
+        return false ;
     } ) ;
 }
 

vasl_templates/webapp/templates/index.html

@@ -23,6 +23,7 @@
 <link rel="stylesheet" type="text/css" href="{{url_for('static',filename='css/select-vo-dialog.css')}}" />
 <link rel="stylesheet" type="text/css" href="{{url_for('static',filename='css/edit-vo-dialog.css')}}" />
 <link rel="stylesheet" type="text/css" href="{{url_for('static',filename='css/vassal.css')}}" />
+<link rel="stylesheet" type="text/css" href="{{url_for('static',filename='css/snippets.css')}}" />
 <link rel="stylesheet" type="text/css" href="{{url_for('static',filename='css/user-settings-dialog.css')}}" />
 
 </head>
@@ -64,6 +65,7 @@
 {%include "edit-vo-dialog.html"%}
 
 {%include "vassal.html"%}
+{%include "snippets.html"%}
 
 {%include "user-settings-dialog.html"%}
 
@@ -97,6 +99,7 @@ gVehicleNotesUrl = "{{url_for('get_vehicle_notes')}}" ;
 gOrdnanceNotesUrl = "{{url_for('get_ordnance_notes')}}" ;
 gGetVaslPieceInfoUrl = "{{url_for('get_vasl_piece_info')}}" ;
 gUpdateVsavUrl = "{{url_for('update_vsav')}}" ;
+gMakeSnippetImageUrl = "{{url_for('make_snippet_image')}}" ;
 gHelpUrl = "{{url_for('show_help')}}" ;
 </script>
 

vasl_templates/webapp/templates/snippets.html

@@ -0,0 +1,4 @@
+<div id="make-snippet-image" style="display:none;">
+    <img src="{{url_for('static',filename='images/loader.gif')}}">
+    Generating the snippet image...
+</div>

vasl_templates/webapp/templates/testing.html

@@ -6,3 +6,4 @@
 <textarea id="_template-pack-persistence_" style="display:none;"></textarea>
 <textarea id="_scenario-persistence_" style="display:none;"></textarea>
 <textarea id="_vsav-persistence_" style="display:none;"></textarea>
+<textarea id="_snippet-image-persistence_" style="display:none;"></textarea>

vasl_templates/webapp/tests/remote.py

@@ -72,6 +72,13 @@ class ControlTests:
         else:
             return json.loads( resp.decode( "utf-8" ) )
 
+    def _get_app_config( self ): #pylint: disable=no-self-use
+        """Get the webapp config."""
+        return {
+            k: v for k,v in app.config.items()
+            if isinstance( v, (str,int,bool,list,dict) )
+        }
+
     def _set_data_dir( self, dtype=None ):
         """Set the webapp's data directory."""
         if dtype == "real":
@@ -257,3 +264,10 @@ class ControlTests:
         _logger.info( "Setting user files: %s", dname )
         app.config["USER_FILES_DIR"] = dname
         return self
+
+    def _get_last_snippet_image( self ): #pylint: disable=no-self-use
+        """Get the last snippet image generated."""
+        from vasl_templates.webapp.snippets import last_snippet_image
+        assert last_snippet_image
+        _logger.info( "Returning the last snippet image: #bytes=%d", len(last_snippet_image) )
+        return base64.b64encode( last_snippet_image ).decode( "utf-8" )

vasl_templates/webapp/tests/test_snippets.py

@@ -1,9 +1,10 @@
 """ Test HTML snippet generation. """
 
+from selenium.webdriver.common.action_chains import ActionChains
 from selenium.webdriver.common.keys import Keys
 
 from vasl_templates.webapp.tests.utils import \
-    init_webapp, select_tab, select_tab_for_elem, set_template_params, wait_for_clipboard, \
+    init_webapp, select_tab, select_tab_for_elem, set_template_params, wait_for, wait_for_clipboard, \
     get_stored_msg, set_stored_msg_marker, find_child, find_children, adjust_html, \
     for_each_template, add_simple_note, edit_simple_note, \
     get_sortable_entry_count, generate_sortable_entry_snippet, drag_sortable_entry_to_trash, \
@@ -307,6 +308,91 @@ def test_edit_templates( webapp, webdriver ):
 
 # ---------------------------------------------------------------------
 
+def test_snippet_images( webapp, webdriver ):
+    """Test generating snippet images."""
+
+    # initialize
+    control_tests = init_webapp( webapp, webdriver, scenario_persistence=1, snippet_image_persistence=1,
+        reset = lambda ct: ct.set_vo_notes_dir( dtype="test" )
+    )
+
+    # check if there is a webdriver configured
+    if "WEBDRIVER_PATH" not in control_tests.get_app_config():
+        return
+
+    # load a test scenario
+    load_scenario( {
+        "PLAYER_1": "german", "PLAYER_2": "russian",
+        "SCENARIO_NAME": "test scenario", "SCENARIO_DATE": "1940-01-01", "SCENARIO_LOCATION": "somewhere",
+        "SCENARIO_NOTES": [ { "caption": "Scenario note #1"  } ],
+        "VICTORY_CONDITIONS": "win at all costs!",
+        "SSR": [ "a test ssr" ],
+        "OB_SETUPS_1": [ { "caption": "OB setup note #1" } ],
+        "OB_NOTES_1": [ { "caption": "OB note #1" } ],
+        "OB_VEHICLES_1": [ { "name": "a german vehicle" } ],
+        "OB_ORDNANCE_1": [ { "name": "a german ordnance" } ],
+        "OB_SETUPS_2": [ { "caption": "OB setup note #2" } ],
+        "OB_NOTES_2": [ { "caption": "OB note #2" } ],
+        "OB_VEHICLES_2": [ { "name": "a russian vehicle" } ],
+        "OB_ORDNANCE_2": [ { "name": "a russian ordnance" } ],
+    } )
+
+    def do_test( snippet_btn, expected_fname ): #pylint: disable=missing-docstring
+
+        # clear the return buffer
+        ret_buffer = find_child( "#_snippet-image-persistence_" )
+        assert ret_buffer.tag_name == "textarea"
+        webdriver.execute_script( "arguments[0].value = arguments[1]", ret_buffer, "" )
+
+        # shift-click the snippet button
+        ActionChains( webdriver ) \
+            .key_down( Keys.SHIFT ) \
+            .click( snippet_btn ) \
+            .key_up( Keys.SHIFT ) \
+            .perform()
+
+        # wait for the snippet image to be generated
+        wait_for( 20, lambda: ret_buffer.get_attribute( "value" ) )
+        fname, img_data = ret_buffer.get_attribute( "value" ).split( "|", 1 )
+
+        # check the results
+        assert fname == expected_fname
+        last_snippet_image = control_tests.get_last_snippet_image()
+        assert img_data == last_snippet_image
+
+    def do_simple_test( template_id, expected_fname ): #pylint: disable=missing-docstring
+        btn = find_child( "button.generate[data-id='{}']".format( template_id ) )
+        do_test( btn, expected_fname )
+
+    def do_sortable_test( sortable_id, expected_fname ): #pylint: disable=missing-docstring
+        entries = find_children( "#{} li".format( sortable_id ) )
+        assert len(entries) == 1
+        btn = find_child( "img.snippet", entries[0] )
+        do_test( btn, expected_fname )
+
+    # do the tests
+    do_simple_test( "scenario", "scenario.png" )
+    do_simple_test( "players", "players.png" )
+    do_sortable_test( "scenario_notes-sortable", "scenario note.1.png" )
+    do_simple_test( "victory_conditions", "victory conditions.png" )
+    do_simple_test( "ssr", "ssr.png" )
+
+    # do the tests
+    select_tab( "ob1" )
+    do_sortable_test( "ob_setups-sortable_1", "ob setup 1.1.png" )
+    do_sortable_test( "ob_notes-sortable_1", "ob note 1.1.png" )
+    do_sortable_test( "ob_vehicles-sortable_1", "a german vehicle.png" )
+    do_sortable_test( "ob_ordnance-sortable_1", "a german ordnance.png" )
+
+    # do the tests
+    select_tab( "ob2" )
+    do_sortable_test( "ob_setups-sortable_2", "ob setup 2.1.png" )
+    do_sortable_test( "ob_notes-sortable_2", "ob note 2.1.png" )
+    do_sortable_test( "ob_vehicles-sortable_2", "a russian vehicle.png" )
+    do_sortable_test( "ob_ordnance-sortable_2", "a russian ordnance.png" )
+
+# ---------------------------------------------------------------------
+
 def _test_snippet( btn, params, expected, expected2 ):
     """Do a single test."""
 

vasl_templates/webapp/webdriver.py

@@ -17,7 +17,7 @@ class WebDriver:
     def __init__( self ):
         self.driver = None
 
-    def start_webdriver( self ):
+    def start( self ):
         """Start the webdriver."""
 
         # initialize
@@ -60,7 +60,7 @@ class WebDriver:
 
         return self
 
-    def stop_webdriver( self ):
+    def stop( self ):
         """Stop the webdriver."""
         assert self.driver
         self.driver.quit()
@@ -111,7 +111,7 @@ class WebDriver:
         # have really large labels, it just affects the positioning of auto-created labels.
 
         window_size, window_size2 = (500,500), (1500,1500)
-        if snippet_id.startswith(
+        if snippet_id and snippet_id.startswith(
             ("ob_vehicles_ma_notes_","ob_vehicle_note_","ob_ordnance_ma_notes_","ob_ordnance_note_")
         ):
             # nb: these tend to be large, don't bother with a smaller window
@@ -119,8 +119,8 @@ class WebDriver:
         return self.get_screenshot( snippet, window_size, window_size2 )
 
     def __enter__( self ):
-        self.start_webdriver()
+        self.start()
         return self
 
     def __exit__( self, *args ):
-        self.stop_webdriver()
+        self.stop()