[Lazarus] New feature: SQLDB Rest bridge

[Michael Van Canneyt]

On Mon, 25 Feb 2019, Sven Barth via lazarus wrote:

> Michael Van Canneyt via lazarus <lazarus at lists.lazarus-ide.org> schrieb am
> So., 24. Feb. 2019, 17:46:
>
>>
>> Hello,
>>
>> We received some feedback about Pas2JS - our effort to bring Pascal to the
>> browser - that easy database connectivity is an issue, hampering easy
>> development.
>>
>> To alleviate the problem I have created the SQLDB Rest bridge.
>>
>> This is a set of components that allow you to expose any database supported
>> by FPC's SQLDB as a REST service. It is designed to be simple to use, yet
>> extensible.
>>
>
> Cool! Great work!
> Now I only need to get the parts for implementing an Interface using RTTI
> working and I'd be all but set :D

You mean for an RPC mechanism ?

Isn't Invoke() working already ? I have a JSON RPC implemention on my list,
and thought to use Invoke() for that.

>
> HTTP:
>> * Authentication is handled using the HTTP protocol.
>>
>> * Basic authentication is included by default, but is completely pluggable.
>>
>> * Basic authentication can look up valid users in a database (by default
>> the database being exposed)
>>
>
> How would one check whether the user is allowed to execute an action?

There is an OnAllowResource event, after the authentication. One of the
parameters is the operation: GET, PUT etc.
If you set the 'allow' to false, you'll get a 403, 'Forbidden'. 
It's not yet committed, because I wanted that together with the business processor component, 
which will make implementing all kinds of events simpler. 
There are stilll several improvements waiting to be tested and committed.

Michael.