I was wondering if there are definite times when you update any changes in lists (such as listed markets) and/or option chains.

For example, if that always happened Friday night, and one would make sure that the app is restarted, or the lists are reloaded, on Saturday, then one could be certain that nothing changes during trading or other times. It would not be necessary to repeatedly reload these lists, saving resources on both client and server.

Thanks for any info on this subject.

It looks like both of these messages were meant for a different topic.

Thanks, I cleaned those up.

Listed markets, trade conditions, and most lookups are all updated on the fly, but normally updates are pushed out over the weekend.

The chains look like they update every morning by around 5 EST.

Tim

Thanks for the info!

So if I load or reload an option chain maybe 1 hour before OPRA market open, there will be no need to check for updates for the rest of the day.

Regarding the listed markets, I did a quick comparison of the current list, and the one you have on your website. It seems the listedMarketID is more stable than the shortname. For example,
ARCA changed to NYSE_ARCA, yet remained at ID 11. And NMS changed to NGM, yet remained at ID 1 (although ID 21 was added).

So does the ID remain the same as long as a listed market exists?

For security types, can we expect that types 1, 2, 6, 8 and 9 will always keep their meaning, even if others are added or removed?
Edited by quickTick on Nov 7, 2017 at 11:42 AM

We do recommend loading it each day at startup to be safe, but other than adds and short/long name changes, you should be safe.

Tim