Object Relations Lab

Welcome to Silicon Valley! For this assignment, our domain is the startup world! We have three models - Startup, VentureCapitalist, and FundingRound. A Startup has many VentureCapitalists through FundingRounds.

Topics

  • Classes vs Instances
  • Variable Scope ( Class, Instance, Local )
  • Object Relationships
  • Instance Methods
  • Class Methods

Notes

Your goal is to build out all of the functionality listed in the deliverables.

We've provided you with a console that you can use to test your code. To enter a console session, run python debug.py from the command line. You'll be able to test out the methods that you write here. Take a look at that file to see how you can pre-define variables and create object instances, rather than manually doing it in every single console session.

Remember! This is an exercise without tests. You cannot run pytest. You'll need to create your own sample instances for testing purposes. Make sure your associations and methods work in the console before submitting.

A note about notation

When you see a '#', this means the functionality will be related to the instance, a '.', the class.

Deliverables

Basic Class Methods, Attributes, and Properties

Build the following on the Startup class

  • Startup#name
    • returns a string that is the startup's name
  • Startup#founder
    • returns a string that is the founder's name
    • Once a startup is created, the founder cannot be changed.
  • Startup#domain
    • returns a string that is the startup's domain
    • Once a startup is created, the domain cannot be changed (ie. A developer working with instances of the Startup class cannot directly change the domain)
  • Startup#pivot
    • given a string of a domain and a string of a name, change the domain and name of the startup. This is the only public method through which the domain can be changed.
  • Startup.all
    • should return a list of all of the startup instances
  • Startup.find_by_founder
    • given a string of a founder's name, returns the first startup instance whose founder's name matches
  • Startup.domains
    • should return an list of all of the different startup domains

Build out the following on the VentureCapitalist class

  • VentureCapitalist#name
    • returns a string that is the venture capitalist's name
  • VentureCapitalist#total_worth
    • returns a number that is the total worth of this investor (e.g., think of it as how much money they have)
  • VentureCapitalist.all
    • returns an list of all venture capitalist instances
  • VentureCapitalist.tres_commas_club
    • returns an list of all venture capitalist instances in the Trés Commas club (they have more then 1,000,000,000 total_worth)

Build out the following on the FundingRound class

  • FundingRound#startup
    • returns the startup object for that given funding round
    • Once a funding round is created, I should not be able to change the startup
  • FundingRound#venture_capitalist
    • returns the venture capitalist object for that given funding round
    • Once a funding round is created, I should not be able to change the venture capitalist
  • FundingRound#type
    • returns a string that is the type of funding round
    • Examples include: Angel, Pre-Seed, Seed, Series A, Series B, Series C, etc.
  • FundingRound#investment
    • returns a number that is the amount invested during this funding round
    • This should be a float that is not a negative number.
  • FundingRound.all
    • returns a list of all of the funding round instances.

Associations and Aggregate Methods

Startup

  • Startup#sign_contract
    • given a venture capitalist object, type of investment (as a string), and the amount invested (as a float), creates a new funding round and associates it with that startup and venture capitalist.
  • Startup#num_funding_rounds
    • Returns the total number of funding rounds that the startup has gotten
  • Startup#total_funds
    • Returns the total sum of investments that the startup has gotten
  • Startup#investors
    • Returns a unique list of all the venture capitalists that have invested in this company
  • Startup#big_investors
    • Returns a unique list of all the venture capitalists that have invested in this company and are in the Trés Commas club

VentureCapitalist

  • VentureCapitalist#offer_contract
    • given a startup object, type of investment (as a string), and the amount invested (as a float), creates a new funding round and associates it with that startup and venture capitalist.
  • VentureCapitalist#funding_rounds
    • returns an list of all funding rounds for that venture capitalist
  • VentureCapitalist#portfolio
    • Returns a unique list of all startups this venture capitalist has funded
  • VentureCapitalist#biggest_investment
    • returns the largest funding round given by this venture capitalist
  • VentureCapitalist#invested
    • given a domain string, returns the total amount invested in that domain