libraries/browser-tracker-core/src/detectors.ts
/*
* Copyright (c) 2022 Snowplow Analytics Ltd, 2010 Anthon Pang
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* 3. Neither the name of the copyright holder nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Checks whether sessionStorage is available, in a way that
* does not throw a SecurityError in Firefox if "always ask"
* is enabled for cookies (https://github.com/snowplow/snowplow/issues/163).
*/
export function hasSessionStorage() {
try {
return !!window.sessionStorage;
} catch (e) {
return true; // SecurityError when referencing it means it exists
}
}
/*
* Checks whether localStorage is available, in a way that
* does not throw a SecurityError in Firefox if "always ask"
* is enabled for cookies (https://github.com/snowplow/snowplow/issues/163).
*/
export function hasLocalStorage() {
try {
return !!window.localStorage;
} catch (e) {
return true; // SecurityError when referencing it means it exists
}
}
/*
* Checks whether localStorage is accessible
* sets and removes an item to handle private IOS5 browsing
* (http://git.io/jFB2Xw)
*/
export function localStorageAccessible() {
var mod = 'modernizr';
if (!hasLocalStorage()) {
return false;
}
try {
const ls = window.localStorage;
ls.setItem(mod, mod);
ls.removeItem(mod);
return true;
} catch (e) {
return false;
}
}