p_pilipovic Copser

Big-O Time Complexities for Elixir data structures

Map [1]

Operation	Time Complexity
Access	`O(log n)`
Search	`O(log n)`
Insertion	`O(n)` for <= 32 elements, `O(log n)` for > 32 elements [2]
Deletion	`O(n)` for <= 32 elements, `O(log n)` for > 32 elements

Working with git remotes on Heroku

Generally, you will add a git remote for your Heroku app during the Heroku app creation process, i.e. heroku create. However, if you are working on an existing app and want to add git remotes to enable manual deploys, the following commands may be useful.

Adding a new remote

Add a remote for your Staging app and deploy

Note that on Heroku, you must always use master as the destination branch on the remote. If you want to deploy a different branch, you can use the syntax local_branch:destination_branch seen below (in this example, we push the local staging branch to the master branch on heroku.

$ git remote add staging https://git.heroku.com/staging-app.git

Deploying to Fly.io with SQLite

Deploying a Phoenix app to Fly.io is a breeze...is what everyone kept telling me. In fairness, I imagine the process would have been breezier had I just used postgres, but all the sqlite and litestream talk has been far too intriguing to ignore. "Wait", you say. "It is just a flat file. How much harder can it be?"

It is easy to make something harder than it should be. It is hard to take something complex and make it truly simple. flyctl launch does an amazing job at providing a simple interface to the utterly complex task of generating deployment resources, especially now that we are living in a containerd (erm, firecracker) world.

This gist is for anyone who, like me, thinks they know better than to read all of the documentation and therefore necessari

Note: Don't do this on a production evniroment!

Get the heroku database name:

heroku pg:info

Name can be found in the reponse from the command above. For example: Add-on: soaring-newly-1337.

	### Keybase proof

	I hereby claim:

	* I am copser on github.
	* I am copser (https://keybase.io/copser) on keybase.
	* I have a public key ASAMxtVKcEvHNiRiJdqPpEdf2QMP_IjhmG-rwZb9tkwSTgo

	To claim this, I am signing this object:

	Erlang/OTP 22 [erts-10.4.4] [source] [64-bit] [smp:12:12] [ds:12:12:10] [async-threads:1] [hipe] [dtrace]

	Interactive Elixir (1.9.1) - press Ctrl+C to exit (type h() ENTER for help)
	iex(1)> TwitterFeed.get_tweets("CandyCrushSaga")
	%TwitterFeed.Feed{
	last_tweet_retrieved: 1204476179719294976,
	more_tweets_exist: true,
	tweets: [
	%TwitterFeed.Tweet{
	display_name: "Candy Crush Saga",

	/*
	* Example implementation
	*/

	- (BOOL)application:(UIApplication )application openURL:(NSURL )url sourceApplication:(NSString *)sourceApplication annotation:(id)annotation
	{
	NSLog(@"Launched with URL: %@", url.absoluteString);

	NSDictionary *userDict = [self urlPathToDictionary:url.absoluteString];

	<html>
	<head>
	<style>
	* {
	font-family:Roboto, "Helvetica Neue", Helvetica, Arial, sans-serif;
	}
	</style>
	</head>
	<body>
	<table cellpadding="0" cellspacing="0" class="email-wrapper" style="padding-top:32px;background-color:#ffffff;"><tbody>

 defmodule Languafy.Web.Context do
   @behaviour Plug
   import Plug.Conn
   alias Languafy.User
   def init(opts), do: opts
   def call(conn, _) do
     case build_context(conn) do
       {:ok, context} ->

	user = Repo.get!(User, user_id) \|> Repo.preload(:roles)
	role = Repo.get!(Role, role_id)

	user_changeset = Changeset.change(user) \|> Changeset.put_assoc(:roles, [role \| user.roles])