4 Component Discovery, Illustrated🔗

11 September 2024

Questions?

4.1 The Idea🔗

Let’s use Bazaar and illustrate the abstract development process from 1-3. We should probably just say it is a board game and leave it at that.

4.1.1 Spiraling away from the Idea🔗

[10-15min]

The idea is simple, namely, we want a “game server for bored hackers”. What concepts, which people, which objects do you think are involved? Let’s tease it out of them.

• concepts: tiles & board; rules; (AI) players; ... we will get back to those later

• people: Bazaar.com; dev ops; hackers; observers (parents, grandparents, e-sports bars, ...)

• objects: server machines; hackers’ machines; displays for paying observers

Here is a concept that doesn’t show up in the “inject sw into a social network” immediately: the referee.

4.1.2 Drawing the Boundary; Use Cases🔗

[5-10min]

remind them of how systems run: start up, steady state, shut down — dynamically link and unlink components

• sign up: a hacker’s client connects an AI player to the game server. Response?

• starting a game: the server has enough players; let’s run a game under the supervision of a referee, which somehow runs turns until the game is over:

  • functionality: referee and an “active” player “converse”

  • limits: non-functional requirements; robustness vs security vs performance ...

  • functionality: inform interested observers of what’s going on

• ending a game: it is the referee that discovers the end of the game. Who needs this information: the company for distributing the prize and the players.

Key insight: there is no such thing as one boundary where stimuli get the system to compute a response but there are many. This indicates the existence of components.

4.1.3 Component Identification🔗

[5-10min]

The boundaries indicate components that talk to each other:

• enumerate components: ref, player.

• dependencies among components

• graph? ordering? –> construction plan

The talking to each other clearly happens at two levels:

• at the level of a game logic

• at the level of an exchange of messages in a distributed system

The result is (a first draft of) the requirements document.

4.2 Milestone 1🔗

[2min]

Just point out that 1 exists and that it consists of two tasks, completely left to their imagination. We don’t answer questions up front. That’s one of the two tasks.

4.3 TA HB PL B🔗

[15-20min]

demo and explain code

Total: 37-57 mins (which does not include the Q&A period)