Update to the original message below:
I started looking into the Network Protocol Tutorial and also the General Concepts (which are both very well written in my opinion) and think it will make more sense for me to begin at very basic level implementing the http/https requests.
Using curl, I can do
curl -v -H "Content-Type: charset=UTF-8" "https://push.cityindex.com/lightstreamer/create_session.txt?LS_op2=create&LS_cid=mgQkwtwdysogQz2BJ4Ji%20kOj2Bg&LS_adapter_set=STREAMINGALL&LS_user=MYUSERID&LS_password=MYSESSIONID" -X GET
where MYUSERID is my user name and MYSESSIONID is the id of an active session I started before with the rest API. Executing the curl command gives no error and results in the output of the LS session id followed by a steady flow of PROBE messages.
For the next step, i.e. the subscription, I need to read more of the above-mentioned documents, but I think something like this should be close:
curl -v -H "Content-Type: charset=UTF-8" "https://push.cityindex.com/lightstreamer/control.txt?LS_session=MYLSSESSIONID&LS_table=1&LS_op=add&LS_data_adapter=PRICES&LS_id=154290&LS_schema=LAST_PRICE&LS_mode=MERGE&LS_snapshot=true" -X GET
where MYLSSESSIONID is the value returned when I created the session.
When I try the command in a second terminal. it isn't quite working yet as it doesn't return the price, but I get a notice in the first window containing the table number.I suspect that the following are good candidates for entries whose values aren't correct yet: LS_data_adapter, LS_schema, LS_mode, LS_snapshot.
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Original message:
Hello again, Gianluca,
So after a slight modification of what you sent, it seems I am getting close, I can connect and disconnect, and the terminal output seems to suggest subscribe and unsubscribe work and there is no error message.
However, there are no prices displayed, and it looks like I can choose some meaningless values for the subscription item and still get no error message. My Cityindex account is a test account and I would be happy to send you a pm with my modified script and credentials if you think you could take a shot at this. Thanks so much!