George Opritescu ♥ Developer from somewhere

install package only for a user with pip

pip install --user some_package

httpoison post example

post_body           = %{"events" => shows} |> Poison.encode!
{:ok, response}     = HTTPoison.post(huginn_url, post_body, %{"Content-Type" => "application/json"})
%{status_code: 201} = response

elixir httpoison

elixir supervised tasks

Useful information found here

{:ok, tas} = Task.Supervisor.start_link(restart: :transient, max_restarts: 4)
Task.Supervisor.start_child(tas, fn ->
  IO.puts "starting child"
  1 = 2 
end)

elixir otp supervisor task

export gitbook as pdf

install

1
gitbook-cli

by using

1
npm install -g gitbook-cli

install calibre with brew, some variation 1 brew install Caskroom/cask/calibre
go to your gitbook folder and run: 1 gitbook pdf ./ ./book.pdf

gitbook git

easy way to copy ssh key to another machine

Install ssh-copy-id by running brew install ssh-copy-id. Then:

ssh-copy-id -p PORT user@some_ip

You need to use PORT if ssh is listening on something other than 22.

ssh

accessing github over port 443

Added the following to .ssh/config, cause 22 was blocked by the network firewall:

Host github-work
  HostName ssh.github.com
  IdentityFile path_to_key
  User your_username
  Port 443

git github firewall

WARNING REMOTE HOST IDENTIFICATION HAS CHANGED

If you get this message:

WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!

when trying to use ssh to login, you can run this command:

ssh-keygen -R </pre>

If ssh-keygen fails, check your `.ssh/known_hosts` file for the entry and delete it.
By the way, do this only if you're sure of what you're doing. The reason I wrote this,
is that I've encountered this message a few times with some VirtualBox machines. 
You might want to double check this ( or probably not do it at all ), if this
happens for a machine connected to the internet ( think staging/prod servers )

ssh

hive and beeline in cloudera

Quickstart:

start beeline

beeline

connect

beeline> !connect jdbc:hive2://localhost:10000 username password org.apache.hive.jdbc.HiveDriver

to insert data from a local file, the file had to have 1 755 permissions on it, and be owned by the user cloudera (?)
if it did not have that, I kept getting errors like this:

0: jdbc:hive2://localhost:10000> LOAD DATA LOCAL INPATH '/user/cloudera/employee.txt' overwrite into table employee;
Error: Error while compiling statement: FAILED: SemanticException Line 1:23 Invalid path ''/user/cloudera/employee.txt'': No files matching path file:/user/cloudera/employee.txt (state=42000,code=40000)

hive beeline cloudera

accessing shared folders in VirtualBox

To be able to view the contents of a shared folder in VirtualBox, your user needs to be part of the

vboxsf

group:

sudo usermod -a -G vboxsf cloudera

The groups the user is part of do not apply right away. Either login again, or restart the VM for this to take effect.

VirtualBox

gzip file and keep it from being deleted

gzip -k file_to_be_compressed

gzip shell