REST Web Services

You need to code your own http client using sockets in the ABL.

When on Windows, you may be using the .NET httpClient class: msdn.microsoft.com/.../system.net.http.httpclient(v=vs.110).aspx

I've used READ-XML and READ-JSON with datasets. Using a URL works perfectly fine with "file" as type. One problem is that only HTTP and not HTTPS is accepted. There's no way of making the call async either.

Example using an X-DOCUMENT:

CREATE X-DOCUMENT ghXmlResponse.

ghXmlResponse:LOAD( "FILE" , "http://ecetc" , FALSE ).

Then you manually need to parse the XML document.

Using temp-tables or datasets has a similar syntax. Read up on datasets specifically!

DATASET dsQuery:READ-XML( "FILE"
, "http://etcetc"
, "EMPTY"
, ?
, ?
, ?
, ?) NO-ERROR.

Most logic is stored in the definition of the datasets and/or temp-tables. Check the manual for more information.

(Disclaimer: Although I am a Progress Employee, the following thoughts are my own and as a user of OpenEdge and I have no pull in this area)

I wondered about the .Net integration to obtain this for a while. I have wondered if a class could not be written to provide an easy interface between OpenEdge and .Net classes to get this (and frankly other web calls) done. When Community was being worked on, I wondered if things like this (and maybe other utility type code) couldn't be worked on by the community in a shared manner in a way that would allow everyone to improve it bit by bit and then have a very useful set of classes that provide useful enhancements ontop of OpenEdge. Sort of community libraries.

If I ever get the free time (at home) to look at this again, I will be sure to share my code.

Just a thought.

Unfortunately, there's no built in REST client in the 4GL. You'd have to use Sockets to implement an HTTP request/response. I think OEHive still has some sample code to be inspired by.