MovieData R6 class

Manages a SQLite database connection for movie data, loads a joined dataset from the omdb and tomatoes tables, and applies filter logic derived from Shiny input values.

Details

On initialization the class opens a connection to the SQLite database at db_path, joins the two tables via inner_join(), collects the result into memory, and stores it in $all_movies. Call $filter() to obtain a filtered data frame for rendering. Call $disconnect() to close the connection explicitly; the private finalize() method also calls it when the object is garbage collected.

Logging is handled via the logger package. Set the threshold with logger::log_threshold() before initializing the class.

Public fields

con

Active DBI database connection.

all_movies

Full joined and collected data frame.

Methods

Public methods

• MovieData$new()

• MovieData$filter()

• MovieData$disconnect()

• MovieData$clone()

---

MovieData$new()

Connect to the SQLite database and load all movie data.

Usage

MovieData$new(db_path)

Arguments

db_path

Path to the SQLite database file (e.g., movies.db).

Returns

The initialized MovieData object invisibly.

---

MovieData$filter()

Filter the in-memory data frame using input values.

Usage

MovieData$filter(
  reviews = 10,
  oscars = 0,
  year = c(1940, 2014),
  boxoffice = c(0, 800),
  genre = "All",
  director = "",
  cast = ""
)

Arguments

reviews

Minimum number of Rotten Tomatoes reviews (default: 10).

oscars

Minimum number of Oscar wins (default: 0).

year

Integer vector of length 2: c(min_year, max_year) (default: c(1940, 2014)).

boxoffice

Numeric vector of length 2: box-office range in millions (default: c(0, 800)).

genre

Genre string; "All" disables the filter (default: "All").

director

Partial director name; empty string disables the filter (default: "").

cast

Partial cast name; empty string disables the filter (default: "").

Returns

A filtered data frame with rows matching all criteria and an added has_oscar column ("Yes" or "No").

---

MovieData$disconnect()

Explicitly close the database connection.

Usage

MovieData$disconnect()

Details

Call this from shiny::onStop() or in tests via on.exit(). The private finalize() method calls this automatically when the object is garbage collected.

Returns

Returns NULL invisibly; called for side effects.

---

MovieData$clone()

The objects of this class are cloneable with this method.

Usage

MovieData$clone(deep = FALSE)

Arguments

deep

Whether to make a deep clone.