Geordi hints

Reminder of what you can do with Geordi.

Note: If you alias Geordi to something short like g, running commands gets much faster!
Note: You only need to type the first letters of a command to run it, e.g. geordi dep will run the deploy command.

geordi deploy

Guided deployment, including push, merge, switch branches. Does nothing without confirmation.

geordi capistrano

Run something for all Capistrano environments, e.g. geordi cap deploy

geordi setup -t -d staging

When you just clon...

Git stash: Working with old entries

First find the reference for the entry you want through looking at the stash:

$ git stash list
stash@{0}: WIP on feature/foo
stash@{1}: WIP on feature/bar
stash@{2}: WIP on fix/baz

Now you can simply use that reference, but curly braces must be escaped:

git stash pop stash@\{1\}

or quoted:

git stash apply "stash@{1}"

Quick reminder to [not shoot yourself in the foot](https://makandracards.com/makandra/634-use-the-git-stash-withou...

How to tackle complex refactorings in big projects

Sometimes huge refactorings or refactoring of core concepts of your application are necessary for being able to meet new requirements or to keep your application maintainable on the long run. Here are some thoughts about how to approach such challenges.

Break it down

Try to break your refactoring down in different parts. Try to make tests green for each part of your refactoring as soon as possible and only move to the next big part if your tests are fixed. It's not a good idea to work for weeks or months and wait for all puzzle pieces ...

Bundler: Gemfile.lock is corrupt & gems are missing from the DEPENDENCIES section

So you're getting this failure when running bundle install on an older project:

Your Gemfile.lock is corrupt. The following gems are missing from the DEPENDENCIES section: 'archive-tar-minitar' 'hoe' 'rcov'

This happens when you are using a new version of Bundler with a project that was bundled with a very old version of Bundler. For reasons unknown, the Bundler dependency API returns different dependencies for some gems (like ruby-debug or rainpress) than the dependencies found in the downloaded gemspecs. While old versi...

How to fix: Bundler 1.13 breaks parallel_tests

When running tests via parallel_tests, you may encounter an error:

cannot load such file -- parallel_tests/gherkin/runtime_logger
Error creating formatter: ParallelTests::Gherkin::RuntimeLogger (LoadError)

This will happen when you upgrade Bundler to version 1.13.x and appears to be "by design" since there is a Bundler config option to restore previous behavior.

You can fix it by setting that flag. You should commit the resulting config file into the repository!

bundle config --local disable_exec_load true

There is a Git...

How to monitor Sidekiq: A working example

In order to have monitoring for Sidekiq (like queue sizes, last run of Sidekiq) your application should have a monitoring route which returns a json looking like this:

{
  "sidekiq": {
    "totals": {
      "failed": 343938,
      "processed": 117649167
    },
    "recent_history": {
      "failed": {
        "2016-11-06": 1,
        "2016-11-07": 46,
        "2016-11-08": 0,
        "2016-11-09": 0,
        "2016-11-10": 0
      },
      "processed": {
        "2016-11-06": 230653,
        "2016-11-07": 230701,
        "2016-11-08"...

Nested ActiveRecord transaction pitfalls

When working with custom transactions and use ActiveRecord::Rollback you may encounter unexpected behaviour if you try to roll back your changes.

tl;dr

When using nested transactions, ActiveRecord::Rollback might not do what you expect, since it will only roll back the inner, but not the outer transaction.

You can fix this behavior by using transaction(joinable: false) but this leads to a bunch of different problems.

When you don't need an explicit ActiveRecord::Rollback, don't worry about any of this and just use a plan `tran...

How to "git diff" with a graphical diff tool

If you are fine with the default console diff most of the time but only sometimes want to use an external tool for viewing a diff, you can use git difftool.

E.g. viewing git diff with meld:

git difftool --tool=meld

For each file in the diff you will be asked if you want to view it using meld.

Git: Show commits that have touched specific text in a file

If you want to find the commits that touched a specific text in a file, use

git log -S 'text in the code' -- path/to/file

If you use tig you may run a similar command to get a navigatable list of affected files:

tig -S'text in the code'

Example

Here is an example, where the move of the convert_number_column_value(value) method in active record is traced (simplified output):

git log -n 1 --pretty=oneline -S 'convert_number_column_value(value)' -- activerecord/lib/active_record/base.rb
ceb33f84933639d3b6...

Git: See more context in a diff

Using the -U parameter you can change how many lines are shown above and below a changed section.

E.g. git diff -U10 will show 10 lines above and below.

Git error: "badTimezone: invalid author/committer line - bad time zone"

You might get the above error message when cloning certain git repositories (for example the rails repository). It indicates that there is a malformed timestamp in some commit, and your git installation is configured to validate it.

As a workaround, you can disable the validation using

git config --global fetch.fsckobjects false

This settings seems to be the default for most git installations anyways.

makandra/gemika: Helpers for testing Ruby gems

We have released a new library Gemika to help test a gem against multiple versions of Ruby, gem dependencies and database types.

Here's what Gemika can give your test's development setup (all features are opt-in):

  • Test one codebase against multiple sets of gem dependency sets (e.g. Rails 4.2, Rails 5.0).
  • Test one codebase against multiple Ruby versions (e.g. Ruby 2.1.8, Ruby 2.3.1).
  • Test one codebase against multiple database types (currently MySQL or PostgreSQL).
  • Compute a matrix of all possib...

Hack of the day: One-liner to run all changed Cucumber features

Similar to our snippet that runs all Cucumber features matching a given string, the following will run all modified or new Cucumber features by looking at your git status:

git status --short | grep -v '^ D ' | grep '.feature' | sed 's/.. //' | tr '\n' ' ' | xargs geordi cucumber

If you want to know what each of the above commands does, see [explainshell](http://explainshell.com/explain?cmd=git+status+--short+%7C+grep+-v+%27%5E+D+%27+%7C+grep+%27.feature%27+%7C+sed+%27s%2F..+%2F%2F%27+%7C+tr+%27%5Cn%27+%27+%27+%7C...

How to tidy up your Git mess

Git is hard: screwing up is easy, and figuring out how to fix your mistakes is fucking impossible. Git documentation has this chicken and egg problem where you can't search for how to get yourself out of a mess, unless you already know the name of the thing you need to know about in order to fix your problem.

So here are some bad situations I've gotten myself into, and how I eventually got myself out of them in plain english*.

Maybe this flowchart may be of help...

Using Spring and parallel_tests in your Rails application

You want Spring for super-fast binstubs like bin/rails or bin/rspec which avoid Rails boot time.
You want parallel_tests to speed up full test runs of large test suites.

Unfortunately, you do not want parallel_tests to use your Spring binstubs as those parallelized tests will share data and/or loose some information. There are some issues about this on GitHub and there is a suggested [workaround](https:...

Git: how to work with submodules

Sometimes you might need to nest a git-project inside another git-project. The right strategy is to use submodules in this case.

How git submodules work

  • Each submodule is a own git repository
  • Once you commit changes in a submodule, the parent repository can link the new sha as its reference
  • You need to take care manually that your git submodules are up-to-date and changes in the submodules are linked in the parent repository

Add a submodule

Here is how you add a nested project inside your parent project

$ git submodule...

How to fix: "rake db:rollback" does not work

When you run rake db:rollback and nothing happens, you are probably missing the latest migration file (or have not migrated yet).

$ rake db:rollback
$ 

If that happens to you, check your migration status.

$ rake db:migrate:status
   up     20160503143434  Create users
   up     20160506134137  Create pages
   up     20160517112656  Migrate pages to page versions
   up     20160518112023  ********** NO FILE **********

When you tell Rails to roll back, it tries to roll back the latest change that was mi...

FreeBSD pkg can't find any packages

If you're trying to searching or installing packages via pkg the your repository data might be broken. If pkg update shows that your repositories are up to date try:

pkg update -f

Afterwards you should be able to search and install packages again.

Install MySQL 5.6 in Ubuntu 16.04

Instead of using this hack you might want to use MariaDB 10.x which can work with both old and new apps.


An alternative could be to use the MySQL Docker image which is still updated for 5.6.


Ubuntu 16.04 only provides packages for MySQL 5.7 which has a range of backwards compatibility issues with code written against older MySQL versions.

Oracle maintains a list of official APT repositories for MySQL 5.6, but those repositories do...

Using Bumbler to Reduce Runtime Dependencies - The Lean Software Boutique

Tool to show you which gems are slow to load:

➜  git:(master) ✗ bundle exec bumbler
[#################################################                             ]
(49/65) travis-lint...
Slow requires:
    110.21  render_anywhere
    147.33  nokogiri
    173.83  haml
    179.62  sass-rails
    205.04  delayed_job_active_record
    286.76  rails
    289.36  mail
    291.98  capistrano
    326.05  delayed_job
    414.27  pry
    852.13  salesforce_bulk_api

An interactive Git shell

Git commands tend to come in groups. Avoid typing git over and over and over by running them in a dedicated git shell.

You might want to run git config --global help.autocorrect true before using gitsh. This will silently swallow a muscle-memory "git" prefix to your commands inside the git shell.

Ever wanted man pages that actually help? Here you go

Enter any command into explainshell and it will explain it to you: split into separate commands (if present), with each option explained.

About

Hello,
This site contains 29761 parsed manpages from sections 1 and 8 found in Ubuntu's manpage repository. A lot of heuristics were used to extract the arguments of each program, and there are errors here and there, especially in manpages that have a non-standard layout.
It is written in Python and uses bashlex, a bit of NLTK (to find the interesting parts of the manpage), a little d3....

Git: auto-stashing to avoid conflicts on pull

First, decide if you want to pull with rebase. There are some implications of changing this, so think before you do it.


If you do, you can tell git to stash automatically before pulling:

git config --global rebase.autoStash true

Now on pull, git will a) stash, b) pull and c) reapply your working tree. Note that applying your changes may lead to unresolvable conflicts!

Further see a common git config with this configuration enabled.

Geordi 1.3 released

Changes:

  • Geordi is now (partially) tested with Cucumber. Yay!
  • geordi cucumber supports a new @solo tag. Scenarios tagged with @solo will be excluded from parallel runs, and run sequentially in a second run
  • Support for Capistrano 2 AND 3 (will deploy without :migrations on Capistrano 3)
  • Now requires a .firefox-version file to set up a test firefox. By default now uses the system Firefox/a test Chrome/whatever and doesn't print warnings any more.
  • geordi deploy --no-migrations (aliased -M): Deploy with `cap ...