Add s3overrides option format

[dsix-work]

The goal of this change is to allow developers to specify any and all options permissible to the AWS.S3 constructor. This is useful when working with other s3-compatible services since we may wish to override a number of options.

This new options format should not break any existing configurations. The downside of configuring this way is that Object.assign() only works on the first level of the objects, so deeper items like params.Bucket could be masked.

[acinader]

You say:

The downside of configuring this way is that Object.assign() only works on the first level of the objects, so deeper items like params.Bucket could be masked.

Can you help me understand what you mean here? I tried to mock up a test of what you're referring too, but I'm a little to dense this morning to get it.

[acinader]

add space after ,

[acinader]

[codecov-io]

Current coverage is 69.84% (diff: 100%)

Merging #24 into master will decrease coverage by 25.03%

@@             master        #24   diff @@
==========================================
  Files             2          2          
  Lines           117        126     +9   
  Methods           9          9          
  Messages          0          0          
  Branches         23         25     +2   
==========================================
- Hits            111         88    -23   
- Misses            6         38    +32   
  Partials          0          0          

Powered by Codecov. Last update bb933cc...7fbe63f

[dsix-work]

@acinader Here's an example of the lack of depth to Object.assign:

x = {a: 1, obj: {a: 1, b: 2}}
y = {a: 2, b: 3}
z = {a: 4, b: 6, obj: {a: 2}}
> Object.assign({}, x, y)
{ a: 2, obj: { a: 1, b: 2 }, b: 3 }
> Object.assign({}, x, z)
{ a: 4, obj: { a: 2 }, b: 6 }

In the second call, we loose the value obj.b since z.obj replaces x.obj entirely.

In the use here, it would mean that this would work:
s3 = new S3Adapter({bucket: "this-bucket"}, {sslEnabled: true})
But this would not work, since params.Bucket would be undefined:
s3 = new S3Adapter({bucket: "this-bucket"}, {params: {ACL: "public-read"}})
You would instead want to configure it like this:
s3 = new S3Adapter({}, {params: {ACL: "public-read", Bucket: "this-bucket"}})

[acinader]

@viawest-davidsix ok, i think i got it.

Since parse-server already uses lodash, we could solve the limitation you raise with acinader@6b6f258

but i'm not sure that's actually an improvement....:).

So if you agree, you can squash this and I'll merge it.

As an side, I haven't gotten around to implementing: #20

but if/when I do (unless you beat me to it ;), I now think that the supported constructors should be:

new S3Adapter(Bucket)
new S3Adapter(s3Options)
new S3Adapter(s3Options, adapterOptions)

Any thoughts welcome.

[dsix-work]

I think the limitation is OK, there are few enough reasons to set params. I agree that implementing #20 would be another re-working of the options. I wonder if it might make sense to be more opinionated about configuration generally at that point?