App access to dashboards

🚧 Developers Coding Questions
1

I'm in the process of writing an app for AAOS that allows me to project Hubitat dashboards in a car running AAOS (different than Android Auto).

My goal is to read the dashboard layout and recreate it in the AAOS App. I'm running into a problem, though. The problem is calling the Hubitat dashboard API from my own Hubitat app.

I pulled out Wireshark and watched the network traffic when I access the dashboard via the local url. The traffic is easy enough to decipher.

Go to the dashboard (url is similar to a regular app url in that is has the access_token query field). In the web page that is returned, buried in the JavaScript, is a variable call javascriptRequestToken. On the second call, the "javascriptRequestToken" is put on the url query string, while the access_token is used in the header for the Authorization. You then send the url path as "layout" and you get the json back with the layout description.

So, using curl, I can faithfully recreate this process and all works just fine. However, if I then go to my hubitat app and code this up, I'm told "connection refused". Oddly, if I use the cloud url for the dashboard, it works fine.

Here is the essence of the code. This first block gets the request token:

String getKeyValue(dashboard){
    def key
    httpGet(uri:"http://<my hub url>/apps/api/<my dashboard id>/dashboard/<my dashboard id>?access_token=<my access token>"){response->
        def pattern=Pattern.compile(/var\s*javascriptRequestToken\s*=\s*"([0123456789abcdef]{8}-[0123456789abcdef]{4}-[0123456789abcdef]{4}-[0123456789abcdef]{4}-[0123456789abcdef]{12})"/)
        def lines=response.data.toString().split('\n')
        def mat

        lines.each{line->
            //mat=line=~pattern
            mat=pattern.matcher(line)
            if(mat.find()){
                key=mat.group(1)
            }
        }
     }
    return key
}

with the local url, it gives me:

org.apache.http.conn.HttpHostConnectException: Connect to <my hub url>:80 [<my hub rul>/<my hub ip>] failed: Connection refused (Connection refused) on line 146 (method getLayoutGET) (note I find it odd that the error points to a function that calls the above function but indicates the line number from the above function.)

Any thoughts?

2

Use port 8080

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3

Well, that was easy. That fixed it. I am curious, though, when I look in WireShark, it clearly indicates port 80 is being used. Why is 8080 the one to use internally to the hub?

4

WireShark is external to the hub and is watching traffic flow between the hub and browser. When the hub is both the host and the destination it needs to use two ports; using port 8080 to have it send requests to itself allows it to use port 80 for the response.

1 Like
5

Thanks for the explanation. As I thought about it, I suspected this was it.

1 Like