I have Calibre installed as an app on TrueNAS Community Edition, but it doesn’t seem like the template includes an option to expose at port for the Calibre content server, only two ports for http and https GUIs. Is there a way to get this included? The linuxserver.io docker instructions indicate that this typically runs on port 8181 under the Calibre docker container.
I’m not at my server so I can’t tell for sure, but the truenas app GitHub seems to have 3 ports that are exposed for editing. The web port, http port, & the https port.
Can you post a picture of what ports you can see when installing the app?
Also just to be clear this is the calibre app and not the calibre-web app right?
Yes, I’m talking about Calibre, not calibre-web. I saw on GitHub that the questions.yaml file lists options for 3 ports, but my installation does not have all three options, only the two.
Under 25.04.1 Calibre ( App Version: v8.4.0 Version: v1.1.3) exposes 32015(http) 32016 (https) and 8081 - content
Interesting. I’m running 25.04.1 Calibre (App Version: v8.4.0 Version: v1.1.3) and I only see ports 32015 (http) and 32016 (https) listed. No mention of port 8081. However, I can confirm that port 8081 works for the content, even though this isn’t documented. As I mentioned above, the questions.yaml file on GitHub references a third port for content, but it defaults to 32014, so I’m not sure how 8081 gets in the mix, but it works, so I’m happy. 
So after a little more poking around and getting feedback on GitHub (Calibre - Can’t Access Content Server · truenas/apps · Discussion #2545 · GitHub) it turns out that the difference in behavior is based on the Host Network option. If the Host Network is enabled (which mine was) then ports 32015 (http) and 32016 (https) are mapped for the Calibre web GUI, and the container is then allowed to choose what port it uses for the content server. Calibre defaults to port 8081 for the content server, but it is changeable under the Calibre settings.
However, if the Host Network is disabled, ports 32015 (http) and 32016 (https) are still mapped for the Calibre web GUI, but an additional port of 32014 is mapped for the content server and ties to container port 8081. Unfortunately, you cannot change port 8081 in the TrueNAS GUI, because it doesn’t present itself as an option, so if you change this port in Calibre’s settings in the container, you will lose access to your content server.