018282f392
This was discussed and agreed in #246. It will probably break a few outstanding PRs as well as a few external links but it's for the better good long term.
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Declarative vs imperative
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Our container orchestrator puts a very strong emphasis on being declarative
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Declarative:
I would like a cup of tea.
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Imperative:
Boil some water. Pour it in a teapot. Add tea leaves. Steep for a while. Serve in a cup.
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- Declarative seems simpler at first ...
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- ... As long as you know how to brew tea
Declarative vs imperative
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What declarative would really be:
I want a cup of tea, obtained by pouring an infusion¹ of tea leaves in a cup.
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¹An infusion is obtained by letting the object steep a few minutes in hot² water.
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²Hot liquid is obtained by pouring it in an appropriate container³ and setting it on a stove.
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³Ah, finally, containers! Something we know about. Let's get to work, shall we?
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.footnote[Did you know there was an ISO standard specifying how to brew tea?]
Declarative vs imperative
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Imperative systems:
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simpler
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if a task is interrupted, we have to restart from scratch
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Declarative systems:
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if a task is interrupted (or if we show up to the party half-way through), we can figure out what's missing and do only what's necessary
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we need to be able to observe the system
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... and compute a "diff" between what we have and what we want
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