wip, may be, never publish
This commit is contained in:
parent
96646455bd
commit
9dcedab3aa
|
@ -39,10 +39,108 @@ What provide a good algebraic abstraction is the certainty that your system
|
|||
will be *composable* upon some properties.
|
||||
So the important word here is *composability* which is arguably superior to /modularity/.
|
||||
|
||||
Modularity is about combining different systems.
|
||||
Here are a few example about how far we could / should go.
|
||||
|
||||
[fn:simple-vs-easy] If you want a great overview of the subject, I highly
|
||||
suggest you to watch [[https://thestrangeloop.com/2011/simple-made-easy.html][Simple made Easy]] video from Rich Hickey.
|
||||
[fn:einstein] This is only attributed to Albert Einstein. He apparently
|
||||
said something similar but we don't have any strong evidence he wrote or
|
||||
said exactly that.
|
||||
|
||||
* CRUD+Search
|
||||
:PROPERTIES:
|
||||
:CUSTOM_ID: crud-search
|
||||
:END:
|
||||
|
||||
With this simple abstraction you could build successful API.
|
||||
|
||||
#+begin_src clojure
|
||||
(defprotocol CRUDPS
|
||||
(create [this id value])
|
||||
(read [this id])
|
||||
(update [this id new-value])
|
||||
(delete [this id])
|
||||
(patch [this id new-partial-value])
|
||||
(search [this partial-value pagination-parameters]))
|
||||
#+end_src
|
||||
|
||||
One important detail is that we could provide "partial values".
|
||||
So we should have a language that should support the notion of "sub-object".
|
||||
And if you are doing this in javascript, this should be easy.
|
||||
In Java or Haskell, it might be a bit more funky.
|
||||
|
||||
So just that. It is even simpler than an ORM.
|
||||
You don't need more than that most of the time.
|
||||
If you force yourself to work within this restriction this give you
|
||||
immediately a few pretty good properties.
|
||||
|
||||
1. *Portability*; This protocol is so simple to write it is easy to implement
|
||||
it for different DBs. Postgres, ES, MongoDB, etc...
|
||||
2. *Scalability*; as this only focus on a single table/index, you do not have
|
||||
to think about join.
|
||||
One of the most important property of my system is generally to never
|
||||
write join.
|
||||
And you can go surprisingly far without the need of any join.
|
||||
In fact, most of the time "fake join" are more efficient, et good enough
|
||||
for almost all user facing use case.
|
||||
3. *Simplicity*; by only using this API internally, it is easy to manipulate
|
||||
DB accesses.
|
||||
|
||||
|
||||
Use HTTP, with 90% CRUD + Search.
|
||||
This is enough for most use cases.
|
||||
And by search, don't think about something too fancy.
|
||||
A sub-JSON will be enough for most use case.
|
||||
Then later you will probably want to add text search/matching.
|
||||
Why sub-JSON is probably superior to your SQL query?
|
||||
Because it is composable, more precisely this is a morphism, which SQL
|
||||
queries aren't.
|
||||
|
||||
What do I precisely mean by "sub-JSON"?
|
||||
|
||||
Simply the ~<@~ operator in Postgres.
|
||||
Or the basic MongoDB/ES search.
|
||||
Not some system introducing complex structure.
|
||||
|
||||
So you want to match:
|
||||
|
||||
#+begin_src js
|
||||
{"foo":"bar"}
|
||||
|
||||
// should match with
|
||||
|
||||
{"foo": bar,
|
||||
"x": "y"}
|
||||
|
||||
// but shouldn't match
|
||||
|
||||
{"foo":"notbar",
|
||||
"x":"y"}
|
||||
//nor
|
||||
{"x":"y"}
|
||||
#+end_src
|
||||
|
||||
So this is a morphism with the following property:
|
||||
|
||||
#+begin_src
|
||||
(find x) AND (find y) <=> (find (x inter y))
|
||||
#+end_src
|
||||
|
||||
Which is not possible to easily do with a SQL query.
|
||||
If you have a string representing a query Q1, and another string
|
||||
representing a query Q2.
|
||||
It is difficult to produce a query for Q1 AND Q2.
|
||||
Because, there are field selection for example.
|
||||
|
||||
For most modern web application/API you don't need to enforce strong
|
||||
constant on that either.
|
||||
For example, you can loose so much time trying to support a great update or patch.
|
||||
Doing so in a concurrent system is hard.
|
||||
If you don't care much, most of the time this will be perfectly ok.
|
||||
|
||||
So just with that and the correct data structure.
|
||||
No search by text, no join.
|
||||
Just 1 table, per data structure saving JSON + the ability to search by sub-json.
|
||||
We created, multiple time, a big reliable and nice to use API.
|
||||
|
||||
No surprise, no discussion about query optimization, no problem about scalability.
|
||||
|
|
Loading…
Reference in a new issue