No JSON object could be decoded- orion context broker - fiware

Question

I am trying out orion context broker comunication on two CentOS 6.6 machines. On the target machine I did:
./accumulator-server.py 1028 /accumulate mywebpage.lan on
And on my local machine I did:
[DevF12#localhost ~]$ (curl mywebpage.lan:1028/v1/updateContext -s -S --header 'Content-Type: application/json' --header 'Accept: application/json' -d #- | python -mjson.tool ) <<EOF
> {
> "contextElements": [
> {
> "type": "Room",
> "isPattern": "false",
> "id": "Room2",
> "attributes": [
> {
> "name": "temperature",
> "type": "float",
> "value": "777"
> },
> {
> "name": "pressure",
> "type": "integer",
> "value": "711"
> }
> ]
> }
> ],
> "updateAction": "APPEND"
> }
> EOF
The result on the target machine is:
POST http://mywebpage.lan:1028/v1/updateContext
Content-Length: 456
User-Agent: curl/7.19.7 (x86_64-redhat-linux-gnu) libcurl/7.19.7 NSS/3.16.2.3 Basic ECC zlib/1.2.3 libidn/1.18 libssh2/1.4.2
Host: mywebpage.lan:1028
Accept: application/json
Content-Type: application/json
{ "contextElements": [ { "type": "Room", "isPattern": "false", "id": "Room2", "attributes": [ { "name": "temperature", "type": "float", "value": "777" }, { "name": "pressure", "type": "integer", "value": "711" } ] } ], "updateAction": "APPEND"}=======================================
192.168.1.11 - - [14/Apr/2015 15:07:36] "POST /v1/updateContext HTTP/1.1" 200 -
And the message I get from the local machine is:
No JSON object could be decoded
So, what does this all mean?
1. Is the 200 code saying that it is successfully creating Room2?
2. Why am I getting the could not decode JSON then?
3. All of this brings up another question, does this mean that the weather station described in my previous post also has to run on CentOS in order to send context broker messages?

Answer 1

I think there is a "conceptual" misunderstanding in your test. You are sending the updateContext to 1028 which is not the port of CB (the one supposed to process updateContext messages) but the accumulator port (which purpose is process notifyContext message sent by CB as a consequence of updateContext messages, but not processing updateContext messages themselves).
Typically, Orion Context Broker runs in port 1026 by default.
Taking into account this, the specific answers are:
Is the 200 code saying that it is successfully creating Room2? No. 200 reported by accumulator just mean that the accumulator has received and acknowledge a message (any message, given that accumulator is a "dummy" application just for testing, it is not doing any real processing of that).
Why am I getting the could not decode JSON then? Try to remove | python -mjson.tool in the curl command line.
All of this brings up another question, does this mean that the weather station described in my previous post also has to run on CentOS in order to send context broker messages? Not sure about the "weather station" in your case, but if you mean the client sending updateContext to CB, it doesn't need to run in CentOS. The only requirements for the client is to be compliant with Orion API and have network connectivity to that host (and port) where Orion is listening.