ErnestK - Rgrep

Introduction

A Ruby gem, just for showing on interview. This is alternative for Bash grep, but in that library implemented only 3 most common operations.

Features

When I develop gem I wish to implement really CLI commands like true "grep". Thats why I used gem "thor", which help me with that. Now we can call commands from console and pass arguments. Also we can pass multipule arguments - I detailed will described it below in section "Usage". You can see all commands in console:

cd lib
ruby Rgrep.rb --help

Some problems coming with that gem:) cause his dont have stable version yet. As an example I cant write whole spec test like I wont - I cant write section "failed when", because I should to rewrite some methods in thor gems. TODO: as fast as I can find some time:)

Also I used gem "os" which help me works correct on Windows/Mac/Linux. This is great gem - really love it.

Installing

You can simple install gem by command:

gem install Rgrep

after that you can check in irb:

irb(main):002:0> Rgrep.start(["--help"])
Commands:
  irb Difference between two files                              # diff file1 ...
  irb List all running_process                                  # list -n 'My...
  irb Search by names in dir/contents of files -n, --name=Name  # find --dir ...
  irb help [COMMAND]                                            # Describe av...
=> {}
irb(main):003:0>

Notes

• Gem works correct on Windows, Mac and Linux.
• You should have ruby > 1.9.
• Gems dependency( of course in gemspec also): thor, os, rspec.

Usage

In that gem was been implemented three operations that inspired by work with "grep".

LIST:

Inspired by "ps aux | grep" - Its not really grep fucntions, but most users common used grep like that, thats why I implemented fuction "list".

Without arguments:

cd lib
ruby Rgrep.rb list

or on ruby

Rgrep.start(["list"])

This is equivalent "ps aux" in Linux/Mac and "tasklist" in Windows. operations list, like all CLI commands, have parameters: name, greater-than and less-than.

--name

Show all runing process with name that we passed in arguments:

ruby Rgrep.rb list --name chrome

or on ruby

Rgrep.start(["list","--name","chrome"])

we also can just pass only part of word.

cd lib
ruby Rgrep.rb list --name chr

or on ruby

Rgrep.start(["list","--name","chr"])

--greater_than

Show all runing process that allocate greater than memory:

ruby Rgrep.rb list --greater-than 100

or on ruby

Rgrep.start(["list","--greater-than","100"])

--less_than

Show all runing process that allocate less than memory:

ruby Rgrep.rb list --less-than 500

or on ruby

Rgrep.start(["list","--less-than","500"])

combinig parameters:

You can combine all parameters:

ruby Rgrep.rb list --name chr --less-than 500 --greater-than 100

or on ruby

Rgrep.start(["list","--name","chr","--less-than","500","--greater-than","100"])

example result:

1:      chrome.exe                    4220 Console                    1   205 440 КБ
2:      chrome.exe                    3672 Console                    1   159 148 КБ
3:      chrome.exe                    4972 Console                    1   107 756 КБ
4:      chrome.exe                    3800 Console                    1   105 880 КБ
5:      chrome.exe                    6324 Console                    1   135 860 КБ
6:      chrome.exe                    7456 Console                    1   104 260 КБ
7:      chrome.exe                    5084 Console                    1   107 396 КБ

DIFF:

Inspired by "grep -f file1 file2" - used to find difference between two files.

Without arguments:

In common case "diff" shows difference lines between two files. In 1 block - show lines that we have only in first file, and in other only lines from second files

cd lib
ruby Rgrep.rb diff /home/Documents/1.txt /home/Documents/2.txt

or on ruby

Rgrep.start(["diff","/home/Documents/1.txt","/home/Documents/2.txt"])

output example:

File: /home/Documents/1.txt
**************************************
File: /home/Documents/2.txt
2: different line

--show_similar

Show similar lines instead different.

ruby Rgrep.rb diff /home/Documents/1.txt /home/Documents/1.txt --show_similar

or on ruby

Rgrep.start(["diff","/home/Documents/1.txt","/home/Documents/2.txt","--show_similar"])

FIND:

Inspired by simple "grep" - search for files and for contents in file.

Without arguments:

Search only for file names or directory names, not for contents.

cd lib
ruby Rgrep.rb find /home/Documents --name Diary 

or on ruby

Rgrep.start(["find","/home/Documents","Diary"])

output example:

Dir:
/home/Documents/TestGit/TestGit/Diary.txt
/home/Documents/YAFU/app/Diary.txt

--contents

In additionally search for the contents. Shows also nuber of lines and file.

ruby Rgrep.rb find /home/Documents --name Diary --contents

or on ruby

Rgrep.start(["find","/home/Documents","Diary","--contents"])

output example:

Dir:
/home/Documents/TestGit/TestGit/Diary.txt
/home/Documents/YAFU/app/Diary.txt
*******************************************************
Into files:
/home/Documents/Rgrep/lib/Rgrep.rb            104:   desc "Search by names in dir/contents of  files", "find --dir --contents '/home' --name 'Diary'"
/home/Documents/Rgrep/spec/rgrep_spec.rb      50: expect(Rgrep.start(["find", PATH.to_s, "--name", "Diary"]).to_i).to eq( CLI_VALID_RESPONSE)
/home/Documents/Rgrep/spec/rgrep_spec.rb      53: expect(Rgrep.start(["find", PATH.to_s, "--name", "Diary", "--contents"]).to_i).to eq( CLI_VALID_RESPONSE)
/home/Documents/TestGit/TestGit/Diary.txt     5: Diary for test

Tests

Off course I developed test using "rspec" for gem. You can run it:

cd spec
rspec rgrep_spec.rb

output example:

.

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