- Zope - Zope lists

how to request a multiple select list?
by Juergen R. Plasser / HEXAGON 22 Jan '02

22 Jan '02

Hi, I am almost new to Zope and HTML-Forms, so I have run into some difficulties. I have just a problem with a lines property of an object that should be edited. I use a form with hidden fields (for the lines property of the object there is a <input name="abc" type="hidden" values="<dtml-var user_list>">). When the user now clicks the edit button the action (let's call it action_html) should be executed. In action_html I'd like to show the user the current values (for the list it must be a multiple select) and give him/her the chance to change the properties. But how can I request the list from the previous form? I always get a list including one string (which is a list itself), like this ["['user1','user2','user3']"]. How can I simply forward the variable/value from the one form to the other? Or is it possible to request the object properties from the given id? Besides that, is there a simple solution to select the given list values in a multiple select tag? I have a workaround that looks like this: <SELECT name="newBenutzerliste:list" size="8" width="16" multiple> <dtml-in get_valid_userids> <dtml-let seqi=sequence-item> <dtml-call "REQUEST.set('sel',0)"> <dtml-in Benutzerliste> <dtml-if expr="_['seqi']==_['sequence-item']"> <OPTION selected value="<dtml-var sequence-item html_quote>"><dtml-var sequence-item></OPTION> <dtml-call "REQUEST.set('sel',1)"> </dtml-if> </dtml-in> <dtml-if sel> <dtml-else> <OPTION value="<dtml-var sequence-item html_quote>"><dtml-var sequence-item></OPTION> </dtml-if> </dtml-let> </dtml-in> </SELECT> Juergen

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Creating ZClass instances at different locations
by Simon Brogden 22 Jan '02

22 Jan '02

Hello, I've got a ZClass, instances of which are created programmatically. That bit works fine, but ... I can't get my head round how to specify where the instance is created. I'm using a Formulator form (great product BTW) to capture the stuff the class needs and perform the validation. Trouble is, the class instace is being created inside the Formulator form. The DTML I'm using to create the instance is: <dtml-with "form"> <dtml-try> <dtml-call "validate_all_to_request(REQUEST)"> <dtml-except FormValidationError> <dtml-var standard_html_header> <ul> <dtml-in "error_value.errors"> <li> <dtml-var "field.get_value('title')">: <dtml-var error_text> </li> </dtml-in> </ul> <dtml-else> <dtml-with "manage_addProduct['MyProduct']"> <dtml-call "MyProduct_add(_.None, _, NoRedir=1)"> </dtml-with> </dtml-try> </dtml-with> What I want to do is have the instance created at a location specified by a property. If the form & DTML method used to create the instance lived in "/MyFolder/MyForms/Add" and I created a string property, say on "MyFolder" level, named "create_in" and set it to "/MyFolder/MyClasses", the class would be created in that folder. I've had a butchers through the list archives and get the impression that I'm approaching this the wrong way. It seems that the location that the instance is created in is based on where the code creating it is stored. Thanks for your time, Simon.

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question about using parameters and action converters together
by H.de.Wit＠SFK.NL 22 Jan '02

22 Jan '02

Hello, This is working: <input type="submit" value="do-something!" name="apythonscript:method"> but this not: <input type="submit" value="do-something!" name ="apythonscript?number=4:method"> i get this as an answer: Resource not found Resource: http/................apythonscript%3Fnumber%3D4 Why is this and what can i do about it The traceback states: Traceback (innermost last): File M:\Program Files\Zope\lib\python\ZPublisher\Publish.py, line 223, in publish_module File M:\Program Files\Zope\lib\python\ZPublisher\Publish.py, line 187, in publish File M:\Program Files\Zope\lib\python\Zope\__init__.py, line 226, in zpublisher_exception_hook (Object: hetformulier) File M:\Program Files\Zope\lib\python\ZPublisher\Publish.py, line 162, in publish File M:\Program Files\Zope\lib\python\ZPublisher\BaseRequest.py, line 373, in traverse File M:\Program Files\Zope\lib\python\ZPublisher\HTTPResponse.py, line 540, in notFoundError NotFound: (see above) Thanks in advance Hans de Wit Stichting Farmaceutische Kengetallen Postbus 30460 2500 GL DEN HAAG Tel. 070-3737448 Fax 070-3737445

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Adding a Factory results in a new ZCatalog index type
by Maik Jablonski 22 Jan '02

22 Jan '02

hello, zope is really great, but sometimes i don't know what to do.... ;-) when i add a new product through the zope management interface (call it myTest for example) and then add a new Zope Factory in this Product (with the "Add list name" something like TEST), "TEST" will be also listed in the "Select type to add"-list of the Index-Tab in a ZCatalog... I've tested this on fresh installations of 2.4.3 and 2.5.0b4. same results. i think i must do something with "filtered_meta_types", but i don't know what. can anyone give me clue? or is it a bug? greetings, mjablonski.

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Using IIS to proxy requests to Zope
by Tom Nixon 22 Jan '02

22 Jan '02

Does anyone know what the easiest way is to get IIS to proxy requests to Zope? I've got Zope listening on port 8080 and I can access it no problem. What I want to do is get http://www.somedomain.com returning pages from Zope. Any ideas? T.

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IMP & Zope integration HOWTO
by Milos Prudek 22 Jan '02

22 Jan '02

IMP integration with Zope HOWTO Version 0.8 January 2002 INTRODUCTION: ============= IMP is a popular and powerful webmail system available at no cost from http://www.horde.org. IMP is written in PHP. Zope is a web application framework. A decent webmail system has not yet been written for Zope. INGREDIENTS: ============ - Zope (tested with Zope 2.4.3) - SQL database (tested with PostgreSQL 7.1.3) - IMP (tested with IMP 3.0 / Horde 2.0) - IMAP server (required by IMP; you may be fine with just a POP3 server, but I did not test that yet) - exUserFolder (abbreviated as XUF) (tested with 0.9.0) RESULT: ======= At the of this tutorial, you will be able to sign-in to IMP any user that is currently authenticated in Zope. The user will not need to re-authenticate manually against IMP. STEPS: ====== Install and test XUF. Make sure that your imap server accepts users and passwords defined in XUF. For this example it is sufficient to instantiate XUF with Null property source, Null membership source, and PostgreSQL authentication source. This HOWTO assumes that you instantiated XUF in folder "Folder1". In real world you will need to instantiate XUF in all folders that you need SQL authentication, since root installation of XUF is not recommended. This HOWTO assumes that your Zope is behind Apache, and that it is accessed as http://localhost/Zope. Your IMP should be accessed as http://localhost/horde/imp. NOTE: Zope is behind Apache because otherwise IMP would not be able to get a cookie from ":8080" host, because IMP will be at port 80. For XUF, you will need to create in PostgreSQL a table named "passwd" with at least the following columns: username varchar(64) password varchar(64) roles varchar(255) password_plain text Please read further info in XUF documentation. The "password_plain" column is neccessary for this HOWTO. Since you will store plaintext passwords there, make sure that PostgreSQL is well secured. For Zope/IMP integration, you will need to create in PostgreSQL a table named "zopeimp" with the following columns: taq text username text password text Now within "Folder1" place the following DTML Methods, Python Scripts and ZSQL Methods: PYTHON SCRIPT "set_cookie": from Products.PythonScripts.standard import html_quote request = container.REQUEST RESPONSE = request.RESPONSE luser=ns.SecurityGetUser().getUserName() password_plain=context.get_password_plain(username=luser)[0].password_plain tag1=request.REMOTE_ADDR tag2=DateTime().timeTime() tag=tag1+"-"+repr(tag2) context.insert_tag(tag=tag,username=luser,password=password_plain) RESPONSE.setCookie('zopeimp',tag,path='/') return ZSQL METHOD "get_password_plain" (parameter is username): SELECT password_plain FROM passwd WHERE <dtml-sqltest username op=eq type=string>; ZSQL METHOD "insert_tag" (parameters are tag, username, password): insert into zopeimp values( <dtml-sqlvar tag type=string>, <dtml-sqlvar username type=string>, <dtml-sqlvar password type=string>); DTML METHOD "implogin": <dtml-call "set_cookie()"> <dtml-call "RESPONSE.redirect('http://localhost/horde/imp/myredirect.php')"> Within your filesystem you will need the ../horde/imp/myredirect.php. It is a copy of IMP's original redirect.php file, with a simple patch. Here's the myredirect.php file: <?php /* * $Horde: imp/redirect.php,v 1.23.2.3 2002/01/02 17:05:32 jan Exp $ * * Copyright 1999-2002 Charles J. Hagenbuch <chuck(a)horde.org> * Copyright 1999-2002 Jon Parise <jon(a)horde.org> * * See the enclosed file COPYING for license information (GPL). If you * did not receive this file, see http://www.fsf.org/copyleft/gpl.html. */ define('IMP_BASE', dirname(__FILE__)); require_once IMP_BASE . '/lib/base.php'; // PATCH TO INTEGRATE ZOPE AND IMP STARTS HERE if (!isset($HTTP_COOKIE_VARS["zopeimp"])) { echo "<h2>Your browser did not give neccessary cookie</h2>"; } else { $zi_cookie=$HTTP_COOKIE_VARS["zopeimp"]; $zi_tag=substr($zi_cookie,1,strlen($zi_cookie)-2); $zi_tag="'" . $zi_tag . "'"; // BE SURE TO CUSTOMIZE THE FOLLOWING LINE: $zi_c=pg_Connect("host=localhost port=5432 dbname=maindb user=john password=secret"); $zi_r=pg_exec($zi_c,"SELECT username,password FROM zopeimp WHERE tag=$zi_tag;"); $zi_r2=pg_exec($zi_c,"DELETE FROM zopeimp WHERE tag=$zi_tag;"); $zi_num=pg_numrows($zi_r); if ($zi_num==1) { $HTTP_POST_VARS['imapuser']=pg_result($zi_r,0,"username"); $HTTP_POST_VARS['pass']=pg_result($zi_r,0,"password"); // BE SURE TO CUSTOMIZE POST VARS TO YOUR NEEDS! $HTTP_POST_VARS['server'] = 'localhost'; $HTTP_POST_VARS['actionID'] = '105'; $HTTP_POST_VARS['mailbox'] = 'INBOX'; $HTTP_POST_VARS['port'] = '143'; $HTTP_POST_VARS['maildomain'] = 'domain.com'; $HTTP_POST_VARS['protocol'] = 'imap'; $HTTP_POST_VARS['realm'] = 'domain.com'; $HTTP_POST_VARS['folders'] = 'mail%2F'; $HTTP_POST_VARS['new_lang'] = 'cz_CZ'; $HTTP_POST_VARS['button'] = 'P%F8ihl%E1%B9en%ED+do+syst%E9mu'; } else { if ($zi_num==0) { echo "<h2>Your browser sent a cookie we do not have on file!</h2>"; } else { echo "<h2>Your browser sent a cookie that we have filed more than once!</h2>"; } } } // PATCH TO INTEGRATE ZOPE AND IMP ENDS HERE $action = Horde::getFormData('action', ''); if ($action === 'compose') { $actionID = LOGIN_COMPOSE; } else { $actionID = Horde::getFormData('actionID', IMP_LOGIN); } /* If we already have a session... */ if (isset($HTTP_SESSION_VARS['imp']) && is_array($HTTP_SESSION_VARS['imp'])) { /* Make sure that if a username was specified, it is the current username */ if ((!isset($HTTP_POST_VARS['imapuser']) || $HTTP_POST_VARS['imapuser'] == $HTTP_SESSION_VARS['imp']['user']) && (!isset($HTTP_POST_VARS['pass']) || $HTTP_POST_VARS['pass'] == Secret::read(Secret::getKey('imp'), $HTTP_SESSION_VARS['imp']['pass']))) { if ($actionID == IMP_LOGIN) { $actionID = NO_ACTION; } header('Location: ' . Horde::applicationUrl('mailbox.php?actionID=' . $actionID, true)); exit; } else { /* Disable the old session. */ $imp = false; session_unregister('imp'); header('Location: ' . Horde::applicationUrl(IMP::logoutUrl('login.php', 'failed'), true)); exit; } } /* Create a new session if we're given the proper parameters. */ if (isset($HTTP_POST_VARS['imapuser']) && isset($HTTP_POST_VARS['pass'])) { if (!isset($HTTP_POST_VARS['mailbox'])) { $HTTP_POST_VARS['mailbox'] = 'INBOX'; } if (($reason = IMP::createSession()) === true) { $imp['_login'] = true; $entry = sprintf('Login success for %s [%s] to {%s:%s}', $imp['user'], $HTTP_SERVER_VARS['REMOTE_ADDR'], $imp['server'], $imp['port']); Horde::logMessage($entry, __FILE__, __LINE__, LOG_NOTICE); if (Horde::getFormData('redirect_url')) { header('Location: ' . Horde::getFormData('redirect_url')); exit; } header('Location: ' . Horde::applicationUrl('mailbox.php?actionID=' . $actionID, true)); exit; } else { header('Location: ' . Horde::applicationUrl(IMP::logoutUrl('login.php', $reason), true)); exit; } } /* No session, and no login attempt. Just go to the login page. */ $uri = 'login.php'; if (!empty($HTTP_SERVER_VARS['QUERY_STRING'])) { $uri .= '?' . $HTTP_SERVER_VARS['QUERY_STRING']; } header('Location: ' . Horde::applicationUrl($uri, true)); exit; ?> Everything is in place now. Make sure that the "implogin" DTML Method has View and Access contents information permissions accessible to Authenticated User. Quit your browser. Access http://localhost/Zope/Folder1/implogin. XUF will prompt you to enter your credentials. When you do that, you will be automatically transported to IMP. That's the whole magic. HOW IT WORKS: ============= "implogin" calls "set_cookie()". set_cookie reads plaintext password of the current user. Then set_cookie invents a pretty unique tag. Then set_cookie inserts a new record in a special "zopeimp" table. The record contains the tag, the username and the plaintext password. The tag will be used by IMP to retrieve the password. Therefore, set_cookie stores the tag in a cookie at the client's browser. Note: This cookie expires at the end of browser session. A marginally cleaner solution would be if IMP expired the cookie, but I found it non-trivial to implement. Do it if you want, and send me the patch. Note: The record in "zopeimp" table is destroyed automatically by IMP. It exists for a split of a second, and acts as a glue between Zope and IMP. That's the end of "set_cookie()". We are back at "implogin". Now "implogin" redirects to http://localhost/horde/imp/myredirect.php. Now we are at "myredirect.php". "myredirect.php" will pick the tag from a cookie. It will remove double qoutes and replace them with single quotes, because PostgreSQL does not like double quotes in parameter value. "myredirect.php" will now use the tag to retrieve username and password. It will immediately destroy the record that it just retrieved. Then it will fill in remaining values that are neccessary for successful IMP sign-on. "myredirect.php" contains some simple error checking. RATIONALE: ========== There are more methods possible to achieve the above-described effect. One method would be to use PHPDocument product. This product should enable running PHP code from within Zope. Such solution would be much simpler than the one presented here, because all cookie and SQL magic would be unneccessary. Unfortunately, I was not able to achieve it, so I gave up. Another method would be to keep the plaintext password in a session, such as CoreSessionTracking. The problem here is that you would need a hook in XUF that would execute a "save to cookie" method when successful login happens. It would be great if XUF included a hook to have user-defined method run when successful login happens. I'm not that good at hacking XUF, so I did not do it that way. Yet another method would be to simply put plaintext password and username into hidden HTML fields and POST it to normal redirect.php. The dissadvantage here is that password would appear in any web cache on the way, and it would be stored at local computer, too. This is so insecure that I never considered such approach. However, this approach would be completely secure if all traffic went through SSL. My goal was to do without SSL and yet achieve some semblance of security. SECURITY CONCERNS: ================== An attacker sitting in between browser and server may intercept the "implogin" request, capture the tag, cut the line to server so that the browser never receives "redirect.php" from server, and present itself as the browser using the tag. However, the attacker that sits between browser and server does not need to do such painful activity in order to read user's mail. He can simply retrieve the password during form authentication, because HTTP is unencrypted. In other words, there are more serious issues for in-between person than cookie hijacking. AFAIK there is only one way to stop these issues: use SSL. FINAL NOTES: ============ This HOWTO describes a fully working solution. The HOWTO is designated version 0.8, because I'm not sure if I put all neccessary information in. Please send your comments to milos.prudek(a)tiscali.cz -- Milos Prudek

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Do you Want to Save Money on Toner Cartridges?
by felipodelacasa＠latinmail.com 22 Jan '02

22 Jan '02

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Date Comparisons
by Yvonne Totty 22 Jan '02

22 Jan '02

Hi people, I need to compare the current date to a result from a query: <dtml-if "DateResult>=TodaysDate"> Where DateResult is from the Query and TodaysDate is Today's Date. How would I go about this? I looked thru all the docs, but could not find an example. Tia, ~~~~~~~~~~~~~~~~~~~~~~~~ Yvonne Totty Database Engineer, x2198

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Need Caching advice for CMF site ...
by Lynn Walton 22 Jan '02

22 Jan '02

If we have a cmf based site with over 500 pages that are CMFDefault.Documents and we are using ZEO with 3 Zope Clients because we have 3 servers in a server farm behind a content switch that does loadbalancing, We're trying to understand all our caching options so we can avoid all 3 clients always hitting the ZEO Server since that sort of defeats the purpose of it being load balanced. Almost of the 500 pages are of a nature that they can be cached since they are not dynamic in the "personalization" sense. (We aren't using the CMF for it's portal like (member join) abilities ... but rather for it's separation of content and workflow abilities for a limited number of employees to update content. Aside from the limited number of employees we set up as owners w/ local roles for maintaining stuff, those hitting our site are always "Anonymous", and the info isn't personalized.) We're thinking about going with mod_proxy's cache abilities because we're using Stronghold which isn't up to Apache 2 yet to use mod_cache. But where I'm confused is about the layer's of caching available in zope. I've tried to read up .. but can't quite tell when it's advised nor how to make use of zope's caching abilities? For instance in a client .. under database management, cache parameters I see this (which I've never messed with so it must be by default): Total number of objects in the database 20518 Total number of objects in all caches 2100 Target Size 400 Target max time between accesses 60 Can someone point me to understanding if this level of caching stops the client from making the trip to the ZODB on the ZEO Server. Does is make the mod_proxy way less necessary? How are they different? What else should I know to make these decisions? Do the needs for caching of a CMF site differ from a non CMF site, since every CMF content object is having to have a skin applied when it's requested? Thanks, Lynn

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RE: [Zope] Static fail-over
by sean.upton＠uniontrib.com 22 Jan '02

22 Jan '02

The half-dead Zope problem could seemingly be solved with something like Mon, where a box is responsible to monitor its own resources; you could, upon failure of any service using a custom monitor script, trigger an alert script that stops Zope or even stops the network interfaces. Provided that not all of your boxes have the same problem, this seems pretty safe. Sean -----Original Message----- From: Toby Dickenson [mailto:tdickenson@devmail.geminidataloggers.co.uk] Sent: Tuesday, January 22, 2002 3:16 AM To: Chris McDonough Cc: Anthony Baxter; Terry Hancock; zope(a)zope.org Subject: Re: [Zope] Static fail-over On Mon, 21 Jan 2002 19:48:41 -0500, "Chris McDonough" <chrism(a)zope.com> wrote: >Linux Virtual Server works well also as a load balancer. Additionally, >Toby Dickenson's recent patch for Zope hey, that me. > that allows it to peer with Squid as >an ICP server (http://www.zope.org/Members/htrd/icp) is a really interesting >thing; it allows for easy failover at the app level Failover seems to be working well. >as well as rudimentary >balancing at the IP level. load *balancing* was an unexpected bonus, and I am suprised how well it works. I actually developed the system because I wanted the opposite; load *clustering*. I have some large objects that are expensive to transfer from my ZEO server. It is better to send all the requests relating to that object to Zopes that already have the object cached, even if that leads to an uneven load distribution. > In comparison, LVS requires that you poll each >Zope behind the balancer every so often if you want to detect a failure and >react, and unlike any of the fancy $30k load balancers it doesn't look at >HTTP response codes to decide if a server returning a "503" error for >instance can be taken out of rotation. Zope as an ICP peer has this >built-in because it takes the first nonerror response it gets from any Squid >peer. Thats the goal, but my ICP patches arent quite there yet. It is possible for a half-dead Zope to still respond to ICP. I think the ideal solution would use both methods: ICP involves checking before *every* request, therefore the check has to be quick and it cant be very thorough. However, it can respond quickly to catastrophic failures. Separately, perform more thorough checks every so often, where you can tune the frequency of the checks against the cost and thoroughness of each one. I cant think of anything better than the LVS-style poll, since the data path excercises the whole system. Squid has a similar system, but not yet merged into the trunk: http://squid.sourceforge.net/rproxy/backend.html#healtcheck Toby Dickenson tdickenson(a)geminidataloggers.com _______________________________________________ Zope maillist - Zope(a)zope.org http://lists.zope.org/mailman/listinfo/zope ** No cross posts or HTML encoding! ** (Related lists - http://lists.zope.org/mailman/listinfo/zope-announce http://lists.zope.org/mailman/listinfo/zope-dev )

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