darconeous

Tesla Key Card Protocol

Researched by Robert Quattlebaum darco@deepdarc.com.

Last updated 2020-02-03.

mpj

Thoughts on Templating languages

I get a lot of questions about what I think about Vue.

I won't comment too much on Vue in general because I'm not familar enough with it, but I'm very familiar with templating systems, and in articles praising Vue, the fact that it uses templating system instead of JSX is almost always cited as a reason to choose Vue. This drives me up the friggin' wall, because the negative side effects of templates are not communicated or discussed. JSX exists for good reasons. To me, JSX is a great simplification and clear improvement over templates.

Template languages are often sold on looking superficially good. I recently ran across yet another one of these articles citing the wonders of Vue, and especially templates. In this article, this JSX example is included:

cschiewek

To forward X11 from inside a docker container to a host running macOS

1. Install XQuartz: https://www.xquartz.org/
2. Launch XQuartz. Under the XQuartz menu, select Preferences
3. Go to the security tab and ensure "Allow connections from network clients" is checked.
4. Run xhost + ${hostname} to allow connections to the macOS host *
5. Setup a HOSTNAME env var export HOSTNAME=`hostname`*
6. Add the following to your docker-compose:

 environment:

simonw

How to recover lost Python source code if it's still resident in-memory

I screwed up using git ("git checkout --" on the wrong file) and managed to delete the code I had just written... but it was still running in a process in a docker container. Here's how I got it back, using https://pypi.python.org/pypi/pyrasite/ and https://pypi.python.org/pypi/uncompyle6

Attach a shell to the docker container

Install GDB (needed by pyrasite)

apt-get update && apt-get install gdb

michaelficarra

function append(separator) {
  return typeof separator === "string" ? appender(separator, "") : appender("", "").apply(this, arguments);
}

function appender(separator, s) {
  return function tag(literalParts, ...computedParts) {
    s += literalParts[0];
    for (let i = 1; i < literalParts.length; ++i) {
      s += computedParts[i - 1] + literalParts[i];
    }

ryzy

frontend https-in
    mode tcp
    bind *:443 ssl crt /etc/ssl/dummy.pem alpn h2,http/1.1
    use_backend nodes-http2 if { ssl_fc_alpn -i h2 }
    default_backend nodes-http

backend nodes-http
    server node1 web.server:80 check

backend nodes-http2

joepie91

Don't use VPN services.

No, seriously, don't. You're probably reading this because you've asked what VPN service to use, and this is the answer.

Note: The content in this post does not apply to using VPN for their intended purpose; that is, as a virtual private (internal) network. It only applies to using it as a glorified proxy, which is what every third-party "VPN provider" does.

• A Russian translation of this article can be found here, contributed by Timur Demin.
• A Turkish translation can be found here, contributed by agyild.
• There's also this article about VPN services, which is honestly better written (and has more cat pictures!) than my article.

psayre23

Below are the Big O performance of common functions of different Java Collections.


List                 | Add  | Remove | Get  | Contains | Next | Data Structure
---------------------|------|--------|------|----------|------|---------------
ArrayList            | O(1) |  O(n)  | O(1) |   O(n)   | O(1) | Array
LinkedList           | O(1) |  O(1)  | O(n) |   O(n)   | O(1) | Linked List
CopyOnWriteArrayList | O(n) |  O(n)  | O(1) |   O(n)   | O(1) | Array

XueshiQiao

# 1.install gource using HomeBrew
$ brew install gource

# 2.install avconv
git clone git://git.libav.org/libav.git
cd libav 
# it will take 3-5 minutes to complie, be patient.
./configure --disable-yasm
make && make install 

hellerbarde

Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns
L2 cache reference ........................... 7 ns
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns             
Compress 1K bytes with Zippy ............. 3,000 ns  =   3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns  =  20 µs
SSD random read ........................ 150,000 ns  = 150 µs

Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs