Fix expire in explorer

[superkhau]

From @superkhau on September 20, 2016 1:53

KV connector expire feature isn't working properly in explorer:

Step to reproduce

1. Create a typical app with a model and browse to explorer
2. Create an object via set without TTL
3. Try to set TTL using expire

The request will fail with:

{
  "error": {
    "statusCode": 400,
    "name": "Error",
    "message": "ttl is a required argument"
  }
}

Workaround

None at the moment, we probably need to fix this one right away.

Copied from original issue: strongloop-internal/scrum-loopback#1072

[superkhau]

From @bajtos on September 20, 2016 14:59

@superkhau is there any particular reason for keeping this issue private? I would like us to be as transparent and open as possible, otherwise it's difficult to get community involvement. I would like us to default to filling issues in the public loopback project unless there is a good reason for keeping it private.

[superkhau]

From @bajtos on September 20, 2016 15:0

1. Create a typical app with a model and browse to explorer
2. Create an object via set without TTL
3. Try to set TTL using expire

Which request failed? The second one, setting a key without expire? Or the third one? For the third one, I think it's expected that the ttl argument is required, right?

[superkhau]

From @bajtos on September 20, 2016 15:2

@superkhau I am also adding missing Milestone: #Epic KV Connectors to this issue and the others you created recently.

[superkhau]

@bajtos No reason, I should've created in loopback in the first place -- I actually created all the CI issues in scrum-loopback and forgot to switch over for the KV connector issues. Moving.

[superkhau]

Which request failed? The second one, setting a key without expire? Or the third one? For the third one, I think it's expected that the ttl argument is required, right?

@bajtos First request. There is something wrong with explorer not passing the TTL entered in the textbox to the remote method.

[richardpringle]

@superkhau, what does your input look like?

[superkhau]

@richardpringle the remoting for expires is at https://github.com/strongloop/loopback/blob/master/common/models/key-value-model.js#L187-L195.

After some digging, the interesting part is API explorer with the above remoting settings doesn't submit any values in the curl request (missing -d ... contents or -F for form data). Meaning it doesn't submit any data to the backend.

That said, I did a bit more digging into PUT requests and it seems HTML forms only supports GET/POST in the spec (I think there is a proposal for the HTML5 spec -- http://programmers.stackexchange.com/questions/114156/why-are-there-are-no-put-and-delete-methods-on-html-forms).

In a nutshell, API Explorer might be failing because it doesn't support PUT in the form submission while our tests still pass since the API does allow put requests via supertest. Gonna use a workaround, but I think we'll need to create a longer term issue to figure out the cause of this.

I also did some digging into how replaceOrCreate does it in persisted model, but that one works because we submit values via source: 'body' instead of source: 'form'.