Re: Selective auto-deploy of web-apps?
From: Caldarale, Charles R [EMAIL PROTECTED] From: Michael Hackett [mailto:[EMAIL PROTECTED] We want to prompt the user for the database password and boot the database before launching the real application. What user? The user of the web app. In this case, there will only be one user, the user of the machine where the server is running. (The same app will also be used in a typical remote client-server environment, but in that case, we'll be hosting the database and encryption won't be necessary.) I guess we will have to look at controlling the database startup and shutdown within the main app Is there some reason an ServletContextListener won't work? (See section 10.2.2 of the Servlet spec - it seems to describe a situation very close to yours.) That appears to allow the app to receive notification of start up and shut down, but not to control it, correct? Plus, I can't quite see how this is much different than the init/destroy methods of the servlet (except maybe in the case of an app with several servlets, where it sounds like the listener events would be sent after all servlets are initialized; but I could be wrong there). Anyway, I appreciate the attempt, but I don't think that solves my problem of controlling the startup of a webapp or servlet from another webapp or servlet. Maybe having the webapps in two different Hosts, with only one set to deploy on startup? There's probably some other problem with that set up, though, that I haven't thought of. -- Michael - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: Selective auto-deploy of web-apps?
Quoting Caldarale, Charles R [EMAIL PROTECTED]: From: Michael Hackett [mailto:[EMAIL PROTECTED] Subject: Re: Selective auto-deploy of web-apps? Anyway, I appreciate the attempt, but I don't think that solves my problem of controlling the startup of a webapp or servlet from another webapp or servlet. I don't understand why you think this is a good idea. The listener class provides isolation from the main logic of the webapp. Tying two webapps together is counter to the philosophy of the Servlet spec, which emphasizes that webapps are independent, self-contained entities. I don't see how going against that will do much other than introduce unnecessary complication. I agree with you to some extent, but it's a tradeoff. If the servlet itself has to manage the situation where it is up and running (initialized by the container) but the database is not there, that complicates its logic fairly significantly. What I was proposing seemed much simpler, and keeps the main web app completely ignorant of the different database configurations and the extra launch stage. Only the little launcher/login web app would know about that stuff. That seemed to me to be the =less= complicated solution. I see now the use of the listener, but it still won't help. The best I've come up with is to wrap the DataSource in a proxy that prevents access until the database is booted (probably in another servlet or JSP, within the same webapp). - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Selective auto-deploy of web-apps?
Or IMHO, use a request filter to check for the database and then redirect the use to a not available or out of order page. This can easily happen before any processing starts and the servlet need not be any the wiser. --David Michael Hackett wrote: Quoting Caldarale, Charles R [EMAIL PROTECTED]: From: Michael Hackett [mailto:[EMAIL PROTECTED] Subject: Re: Selective auto-deploy of web-apps? Anyway, I appreciate the attempt, but I don't think that solves my problem of controlling the startup of a webapp or servlet from another webapp or servlet. I don't understand why you think this is a good idea. The listener class provides isolation from the main logic of the webapp. Tying two webapps together is counter to the philosophy of the Servlet spec, which emphasizes that webapps are independent, self-contained entities. I don't see how going against that will do much other than introduce unnecessary complication. I agree with you to some extent, but it's a tradeoff. If the servlet itself has to manage the situation where it is up and running (initialized by the container) but the database is not there, that complicates its logic fairly significantly. What I was proposing seemed much simpler, and keeps the main web app completely ignorant of the different database configurations and the extra launch stage. Only the little launcher/login web app would know about that stuff. That seemed to me to be the =less= complicated solution. I see now the use of the listener, but it still won't help. The best I've come up with is to wrap the DataSource in a proxy that prevents access until the database is booted (probably in another servlet or JSP, within the same webapp). - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: Selective auto-deploy of web-apps?
From: Michael Hackett [mailto:[EMAIL PROTECTED] Subject: Selective auto-deploy of web-apps? We want to prompt the user for the database password and boot the database before launching the real application. What user? I guess we will have to look at controlling the database startup and shutdown within the main app Is there some reason an ServletContextListener won't work? (See section 10.2.2 of the Servlet spec - it seems to describe a situation very close to yours.) - Chuck THIS COMMUNICATION MAY CONTAIN CONFIDENTIAL AND/OR OTHERWISE PROPRIETARY MATERIAL and is thus for use only by the intended recipient. If you received this in error, please contact the sender and delete the e-mail and its attachments from all computers. - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Selective auto-deploy of web-apps?
Bonjour Michael Have you looked into using Spring Framework lazy-init=true property e.g objects default-lazy-init=true ? Martin- - Original Message - From: Michael Hackett [EMAIL PROTECTED] To: users@tomcat.apache.org Sent: Thursday, December 08, 2005 5:08 PM Subject: Selective auto-deploy of web-apps? I'm trying to come up with a solution for the following situation: We have a webapp that we need to deploy with an encrypted Derby database. We want to prompt the user for the database password and boot the database before launching the real application. I was thinking of having either: (1) a separate small web app that gets auto-deployed and starts the main web app after unlocking the database, and stops it before shutting down the database; or (2) a second servlet within the web app to do the same thing (the main code is contained inside a single Struts-based servlet) However, in the first case, I can't see a way to have the one web app auto-deploy but not the other (seems to be host-specific, not context-specific); and in the second case, even without a load-on-startup element in the web.xml file for the main servlet, Tomcat still seems to initialize it at startup. (And even if it did, the docs say it would be auto-loaded as soon as its context URL was hit. No way to protect against that.) Am I missing something? I was hoping to do something outside of the main app, to keep it isolated from the database deployment details (there are at least two different configurations, only one of which needs the encryption), but if neither option is possible, I guess we will have to look at controlling the database startup and shutdown within the main app (which looks like it could be messy, what with all the stuff Hibernate, Spring, and Tomcat are doing behind the scenes for us). If anyone here has attempted something like this, I'd love to hear from you. Cheers, -- Michael - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
