loop

loop expands commands to work simultaneously against any number of subdirectories in your current working path. Want to perform a git status on 15 projects at once? With loop, you can do it!

    loop executes a command against child directories within its current working directory

    usage:

      loop [command]                                      - execute a command against all child dirs
      loop ["command with multiple words in quotes"]      - execute a multi-word command against all child dirs
      loop --cwd ../other/working/directory               - execute a command against all child dirs, setting the working directory to another directory
      loop --include comma,delimited,list,of,dirs         - execute a command against all child dirs including a number of directories which might otherwise be ignored, for instance, in .looprc
      loop --include-only comma,delimited,list,of,dirs    - execute a command against all child dirs, ignoring .looprc, and only including the specified directories
      loop --include-pattern 'regexp'                     - execute a command against all child dirs that match the regular expression
      loop --exclude comma,delimited,list,of,dirs         - execute a command against all child dirs, excluding the specified directories
      loop --exclude-only comma,delimited,list,of,dirs    - execute a command against all child dirs, excluding only the specified directories
      loop --exclude-pattern 'regexp'                     - execute a command against all child dirs, excluding directories that match the regular expression
      loop --init                                         - creates a .looprc in the current working directory

    examples:

      loop pwd
      loop "git status"
      loop "git checkout -b feature/new-feature"
      loop "git push origin feature/new-feature"

    .looprc:

      directories containing a .looprc json file may have extra behavior, determined by properties within the file:

        ignore (type Array) any child directory names listed in ignore will be ignored and skipped from execution

    example .looprc:

    {
      "ignore": [ ".git", ".vagrant", ".vscode", "ansible", "node_modules", "scripts" ]
    }

Installation

npm install -g loop

Basic Usage

loop installs a loop command which you can leverage from the command line, in your package.json scripts, etc. The syntax is super simple. Just loop [your command]. If the command you wish to run consists of multiple words, place the command in quotes: loop "your --you | really -R | long -o | command".

In a folder with the following structure:

./git
./bin
./lib
./node_modules
./test
./index.js
./package.json

executing loop pwd yields the following results:

➜  nycnode-site git:(master) loop pwd

.git
/Users/mateodelnorte/development/nycnode/nycnode-site/.git

lib
/Users/mateodelnorte/development/nycnode/nycnode-site/lib

node_modules
/Users/mateodelnorte/development/nycnode/nycnode-site/node_modules

test
/Users/mateodelnorte/development/nycnode/nycnode-site/test

.looprc

loop can use a .looprc file to customize how loop behaves in a particular folder. Installing a .looprc file to a folder is simple:

loop --init results in the following file being created:

{
  "ignore": [ ".git", ".vagrant", ".vscode", "node_modules" ]
}

Now, when we perform the same command we did previously loop pwd, loop will recognize the .looprc file and see the .git folder is ignored - excluding it from the results:

➜  nycnode-site git:(master) loop pwd

lib
/Users/mateodelnorte/development/nycnode/nycnode-site/lib

node_modules
/Users/mateodelnorte/development/nycnode/nycnode-site/node_modules

test
/Users/mateodelnorte/development/nycnode/nycnode-site/test

On to the Fun Stuff

Neat, so now we can ignore folders that we don't work with directly. Imagine having a folder that contains all your project repositories for work. Wish you could find out how many files are in each?

➜  nycnode git:(master) ✗ loop "find . -path ./node_modules -prune -o -type f  | wc -l"

nycnode-denormalizer
125

nycnode-meetup-ingestor
148

nycnode-site
1106

nycnode-user-ingestor
103

nycnode-youtube-ingestor
81

Better yet, what if you're starting a new feature that spans a distributed system composed of many microservices and a site or two?

➜  nycnode git:(master) ✗ loop "git checkout master"

nycnode-denormalizer
Already on 'master'

nycnode-meetup-ingestor
Already on 'master'

nycnode-site
Already on 'master'

nycnode-user-ingestor
Already on 'master'

nycnode-youtube-ingestor
Already on 'master'

➜  nycnode git:(master) ✗ loop "git pull origin master"

nycnode-denormalizer
From github.com:mateodelnorte/nycnode-denormalizer
 * branch            master     -> FETCH_HEAD

nycnode-meetup-ingestor
From github.com:mateodelnorte/nycnode-meetup-ingestor
 * branch            master     -> FETCH_HEAD

nycnode-site
From github.com:mateodelnorte/nycnode-site
 * branch            master     -> FETCH_HEAD

nycnode-user-ingestor
From github.com:mateodelnorte/nycnode-user-ingestor
 * branch            master     -> FETCH_HEAD

nycnode-youtube-ingestor
From github.com:mateodelnorte/nycnode-youtube-ingestor
 * branch            master     -> FETCH_HEAD
 
➜  nycnode git:(master) ✗ loop "git checkout -b feature/my-new-feature"

nycnode-denormalizer
Switched to a new branch 'feature/my-new-feature'

nycnode-meetup-ingestor
Switched to a new branch 'feature/my-new-feature'

nycnode-site
Switched to a new branch 'feature/my-new-feature'

nycnode-user-ingestor
Switched to a new branch 'feature/my-new-feature'

nycnode-youtube-ingestor
Switched to a new branch 'feature/my-new-feature'

Now you're ready to code away across your whole system! loop "git status" will show you your status across all repos. loop "git diff", loop "git push origin feature/my-new-feature", and other commands all work like you'd think!