CS257 Software Design
Monday, 21 April 2025

+ Questions
- Large files and GitHub
- Videos about TCP, HTTP, APIs,...
- Current assignment
- Other

+ URLs in APIs

    protocol://hostname:port/path...?GET-arguments
    http://stearns.mathcs.carleton.edu:9007/movies?before=2010&after=2000&genre=action

Sometimes a site separates the normal web pages from the API:

    http://whatever:9007/home.html
    http://whatever:9007/api/2.0/movies


+ REST and API design
- Principles
    - first component of an endpoint should be a noun
        (right after the first slash following any API prefix like "/api/2.0")
        - if it's plural, you expect to get a list (of strings or dictionaries)
        - if it's singular you expect to get a dictionary
    - use HTTP verbs
        GET (we'll use GET, exclusively)
            ...DELETE, POST, PUSH,...
    - use HTTP error codes (404, 200,...)
    - use GET parameters for filtering results
    - [these days] output should be JSON

- Questions we might want to ask a database of movies and their cast & crew
    - give me a list of movies with certain attributes
        - give me a list of movies based on a rating level and genre
        - give me the best movies for a year
        - given an actor name, give me a list of their movies
    - give me a list of actors with certain attributes
        - given a movie, give me the cast
    - give me a list of directors with certain attributes
    - give me a list of cinematographers with certain attributes
    - give me a list of reviews with certain attributes
        - give me a list of reviews of a specified movie
            /reviews/<movie_id>
            /reviews?movie_id=<id>   Is one of these choices better? Why/why not?
        - give me a list of reviews by a specified person
        - give me a list of reviews from yesterday
    
- Turning those questions into API endpoints

    /actors?rating=<rating>
            movie_id
            given_name? surname? name?...
            year_born
            locations of various sorts (born, live, work,...?)
            ...
      what's the best strategy for searching by name?
        "m" -- Meryl Streep?
        "s"
        "M"
        "e"
        "eryl"
        "p, m
        "l s"
        "l S"
        ...

    /movies?actors=Brad%20Pitt
    /movies?actors=Brad%20Pitt,George%20Clooney -- is that AND or OR
        duplicate names?

===
+ Next: relational databases
- tables
- joins
- example: books & authors