VPN for internal service

Have to setup VPN for internal service, using AWS as VPN server
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AWS VPN in 10 mins:
https://www.webdigi.co.uk/blog/2015/how-to-setup-your-own-private-secure-free-vpn-on-the-amazon-aws-cloud-in-10-minutes/
---
but I don't want all traffic go through VPN, I have to setup routes
using Apple script as below:

property version : "2016-12-01"
property theShellScript : "#!/bin/sh
rm /etc/ppp/ip-up
sudo echo '#!/bin/sh' >> /etc/ppp/ip-up
sudo echo '/sbin/route add -net "destination.com" -interface $1' >> /etc/ppp/ip-up
sudo echo '/sbin/route add -net google.com -interface $1' >> /etc/ppp/ip-up
chmod 0755 /etc/ppp/ip-up
cat /etc/ppp/ip-up"
do shell script theShellScript with administrator privileges

What it does is to put a ip-up file in /etc/ppp, when vpn is connect, the ip-up script will be executed, and route for  "destination.com" will be route through VPN

Update UITableViewCell from itself

The code that can update the cell itself.

// update UI on main thread
dispatch_async(dispatch_get_main_queue(), ^{
    //set cell need update
    [self setNeedsUpdateConstraints];
    [self updateConstraintsIfNeeded];
    [self setNeedsLayout];
    [self layoutIfNeeded];
    //trying to get the tableview
    id view = [self superview];
    // different level of UITableView wrapping in different iOS version,
    // for more detail please see:
    //  stackoverflow 
    while (view && [view isKindOfClass:[UITableView class]] == NO) {
        view = [view superview];
    }
    
    if (view) {
        UITableView *tableView = (UITableView *)view;
        NSIndexPath *indexPath = [tableView indexPathForCell:self];
        if (indexPath) {
            [tableView reloadRowsAtIndexPaths:@[indexPath] 
                             withRowAnimation:UITableViewRowAnimationNone];
        }
    }
});

[JavaScript]Get XMLHttpRequest Traffic

 Case: finding network traffic of a website, can't see relevant in the Console->network in Chrome, dig into code, it is XMLHttpRequest and not log in Console->Network

How: In console add hook into XMLHttpRequest

Code:

var rawOpen = XMLHttpRequest.prototype.open;

XMLHttpRequest.prototype.open = function() {
    if (!this._hooked) {
        this._hooked = true;
        setupHook(this);
    }
    rawOpen.apply(this, arguments);
}

function setupHook(xhr) {
    function getter() {
        console.log('get responseText');

        delete xhr.responseText;
        var ret = xhr.responseText;
        setup();
        console.log('url : %s',xhr.responseURL);
        console.log('ret : %s',ret);
        return ret;
    }

    function setter(str) {
        console.log('set responseText: %s', str);
    }

    function setup() {
        Object.defineProperty(xhr, 'responseText', {
            get: getter,
            set: setter,
            configurable: true
        });
    }
    setup();

Source : http://stackoverflow.com/questions/16959359/intercept-xmlhttprequest-and-modify-responsetext

[iOS] UITableView scroll to top when typing in the textfield will scroll to a wrong location

My case is this:

I have a static table, with hidden cell(height = 0), custom cell that will open keyboard, and a reset button(that will reload table and scroll to top)

What is the problem:

Scroll to top will go to invalid offset.

How to regenerate:

type in the keyboard, reset(which scroll to top and reload the keyboard) and there will be space between my top cell and top of table (just like hidden cell consumed some space)

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At first I thought it is the hidden cell problem, but it turns out to be problem on [tableView reloadData]

**[tableView reloadData] will interrupt scrolling, so make sure you call [tableView setContentOffset:] or [tableView scrollToRowAtIndexPath:] after all reload is done.

Reference: stackoverflow