Git, Project Management, Linux, and Regex Essentials

Git Commands and Concepts

Git key commands and concepts:

• add (stage changes)
• commit (with a message)
• head (most recent commit)
• branch (alternative history)
• checkout (enter/exit branch)
• merge (combine into master)
• stash (save without commit, -u for untracked files; latest stashes (0) at the top)
• pop (retrieve a stash)
• fork (copy code from the source into a repository)
• pull (pull remote changes and merge into master)
• revert (undo commits and create a new commit)
• log (history with most recent commits first, -p for patch details)
• rm (--cached to remove from staging)
• fetch (get changes from a remote repository to a local repository without merging them; useful for reviewing changes)
• pull (fetch + merge)
• rebase (create a clean/linear commit history by moving commits of one branch on top of another)

Project Management Fundamentals

Key factors:

• Assign a Project Manager (PM)
• Manage Scope/Requirement Changes
• Maintain Good Communication

Agile Principles:

• Individuals and interactions over processes and tools
• Working software over comprehensive documentation
• Customer collaboration over contract negotiation
• Responding to change over following a plan

Agile Practices:

• Focus on the customer
• Iterative and incremental delivery
• Experimentation and adaptation
• Self-organization
• Continuous improvement

Scrum Framework

• Sprints: Maximum of 4 weeks; 5-9 people.
• Daily Scrum: 15 minutes maximum; All-Stand.
• Scrum Master: Facilitates the process, does not assign daily tasks.
• Retrospective: Team reviews the process.

Project Requirements

• Functional Requirements: "What" (Users' view) - Describe user expectations; documented by use cases.
• Non-functional Requirements: "How" (Developers' View) - Describe how the system should behave; tie use cases to technical implementation.
• Use Case: A story about how an end-user interacts with the system under specific circumstances.
• User Stories: Description of a feature; requirements; acceptance criteria confirm when a story is complete.
• Epic: A large, general task that can be broken down into smaller user stories; hard to estimate. Format: "As a [user], I want to [action] so I can [benefit]".
• Story Points: A relative measure to assess the size of a user story (ranking system).

Linux Commands

Essential Linux commands:

• pwd (print working directory)
• cd (change directory)
• ls (list directory contents)
• cp (copy)
• rm (delete file)
• mv (move)
• mkdir, rmdir (remove directory)
• chmod (make a file executable, change permissions)
• -r (recursive option for removing files from folders)

Shell and Paths

• Shell: A user program that provides an interface to use OS services.
• Relative Paths:
  • Current directory (.)
  • Parent directory (..)

File Manipulation Commands

• cat (display file contents)
• more (display file contents in a user-friendly manner)
• head (display the first lines of a file)
• tail (display the last lines of a file)
• wc (count lines, words, and characters in a file)
• grep (globally search a regular expression and print)
• sort (sort lines of text)
• uniq (filter out repeated lines)
• cut (cut out selected portions of each line)
• tee (send data to both a file and standard output)

Piping and Redirection

• Piping (|): Connect the output of one process to the input of another.
• VIM:
  • Starts in command mode.
  • i for insert mode.
  • : for last-line mode.
  • :w (write to file)
  • :q (exit editor)
  • :q! (quit without saving)
• echo (print to a file/terminal)
• >> (append to a file)
• > (overwrite a file)

Regular Expressions (Regex)

Regex is a special text string for describing a search pattern.

Version Control Systems

Distributed version control systems are preferred over centralized ones.

• Repository: A version-controlled collection of files/code.
• Revision: A specific version of a repository/file.
• Tag: A logically named/labeled version.
• Diff: The set of changes between two revisions.