Steven Shaw steshaw

Run this in order to backup all you k8s cluster data. It will be saved in a folder bkp. To restore the cluster, you can run kubectl apply -f bkp.

Please note: this recovers all resources correctly, including dynamically generated PV's. However, it will not recover ELB endpoints. You will need to update any DNS entries manually, and manually remove the old ELB's.

Please note: This has not been tested with all resource types. Supported resource types include:

services
replicationcontrollers
secrets
deployments
horizontal pod autoscalers

Context

As a user of Opaleye, I feel that Opalaye's public API is missing a number of features/niceties that are required by most people using the library in a largish project. The number of separate projects trying to close these gaps seem to strengthen this point:

Based on the discussion at silkapp/girella#9, specifically Tom's approval in that thread, this is an effort to build consensus around features that Opaleye's users would like to see in the core library directly. Of course, these features should not compromise general principles that @tomjaguarpaw has specifically mentioned:

Applied Functional Programming with Scala - Notes

1. Mastering Functions

A function is a mapping from one set, called a domain, to another set, called the codomain. A function associates every element in the domain with exactly one element in the codomain. In Scala, both domain and codomain are types.

val square : Int => Int = x => x * x

In response to a request on Reddit, I'm writing up my thoughts on PVP upper bounds. I'm putting this in a Gist since I don't want to start yet another debate on the matter, just provide some information to someone who asked for it. Please don't turn this into a flame war :)

For those unaware: the Package Versioning Policy is a set of recommendations covering how to give version numbers to your packages, and how to set upper and lower bounds on your dependencies.

I'll start by saying: I support completely with the PVP's recommendations on how to assign version numbers. While there are plenty of points in this design space, the PVP is an unobjectionable one, and consistency in the community is good. On multiple occasions, I have reached out to package authors to encourage compliance with this. (However, I've always done so privately, as opposed to a statement on Reddit, as I believe that to be a more likely route to successful convincing.)

The issue aro

Installation of NixOS with encrypted root

These are my notes on instaling NixOS 16.03 on a Lenovo ThinkPad X1 Carbon (4th generation) with an encrypted root file system using UEFI.

Most of this is scrambled from the following pages:

libevent vs libuv

Comparing libevent and libuv. My upfront biased: I want to like libevent. However, I want to objectively compare the two and make an informed decision.

What versions are we comparing?

libevent 2.0.22 (Stable) [2014-01-05]
libuv 1.8.0 (Stable) [2015-12-15]

General notes

nix-channel and ~/.nix-defexpr are gone. We'll use $NIX_PATH (or user environment specific overrides configured via nix set-path) to look up packages. Since $NIX_PATH supports URLs nowadays, this removes the need for channels: you can just set $NIX_PATH to e.g. https://nixos.org/channels/nixos-15.09/nixexprs.tar.xz and stay up to date automatically.
By default, packages are selected by attribute name, rather than the name attribute. Thus nix install hello is basically equivalent to nix-env -iA hello. The attribute name is recorded in the user environment manifest and used in upgrades. Thus (at least by default) hello won't be upgraded to helloVariant.

@vcunat suggested making this an arbitrary Nix expression rather than an attrpath, e.g. firefox.override { enableFoo = true; }. However, such an expression would not have a key in the user environment, unlike an attrpath. Better to require an explicit flag for this.

TBD: How to deal with search path clashes.

	;; nice glyphs for haskell with hasklig
	;; copied that code from some pastebin, but forgot where
	(custom-set-variables '(haskell-font-lock-symbols t)
	'(haskell-font-lock-symbols-alist
	(and (fboundp 'decode-char)
	(list (cons "&&" (decode-char 'ucs #XE100))
	(cons "***" (decode-char 'ucs #XE101))
	(cons "*>" (decode-char 'ucs #XE102))
	(cons "\\\\" (decode-char 'ucs #XE103))
	(cons "\|\|" (decode-char 'ucs #XE104))

	# I wanted to use ensime with vim, which requires vim + python + some python packages (websocket_client + sexpdata)
	# unfortunately, nix would build vim with a python that didn't have access to my system libraries (for referential transperancy)
	# so I needed to provide to `vim_configurable.nix` the right python to use and enable python, lua, etc. support.
	# I also wanted to keep my `.vimrc` separate because some of the vim packages I use weren't available.
	#
	# install via: `nix-env -f '<nixpkgs>' -iA myCoolVim` or `nix-env -I nixpkgs=/path/to/your/nixpkgs -f '<nixpkgs>' -iA myCoolVim`
	#
	# out put of `vim --version` below.

	{

	# see https://www.topbug.net/blog/2013/04/14/install-and-use-gnu-command-line-tools-in-mac-os-x/

	# core
	brew install coreutils

	# key commands
	brew install binutils
	brew install diffutils
	brew install ed --default-names
	brew install findutils --with-default-names