ELOG FAQ

Frequently Asked Questions about usage and configuration
Please check also the ELOG Forum.

1. How does one configure elog to display the last message by default
2. Are there any plans to implement a MySQL back end?
3. Can I run the ELOG daemon from inside Apache or any other Web server?
4. I can access my logbook without any password, isn't that a security problem?
5. I want a bookmark pointing to the last page where an attribute has a certain value
6. I want a logbook with public read access (no password), but restricted write access
7. I have many loogbooks with password files, so if I add a user or want to change a password I have to do this for all logbooks which is painful.
8. How can I configure ELOG such that it displays something else than the message list by default?
9. I want to have additional commands specific to my lookbook
10. How does one configure elog to disable editing of existing messages? I want a logbook where one can enter messages but not change them afterwards.
11. How can I track various revisions of a message using the "edit" command?
12. How can I enter a date which is different from current one?
13. I cannot pass the login page, it's always redisplayed even if I put in the right password?
14. How can I change an attribute for an entire thread? We have an attribute "open problem/fixed" which should be changed for the whole thread if that problem has been fixed.
15. Can I use RSS feeds with password protected logbooks?
16. How can I mark a whole thread open or closed?
17. Does elog have a spell checker?
18. Why are entries with large attachments submitted so slowly?
19. The elgod daemon crashes from time to time, what can I do?
20. How can I create an ELOG entry automatically from a script?
21. I want to notify different people for different things, how do I set up this?

1. How does one configure elog to display the last message by default

   One can use the `Start page` option for that. The entry:

   `Start page = 0?cmd=last`

   shows the last message entry by default. To have the described behaviour for all logbooks, the above statements can be placed in the `[global]` section.

2. Are there any plans to implement a MySQL back end?

   No. The idea behind ELOG is that it is a simple to use, simple to install application. Many people use ELOG under Windows, and they even don't know what MySQL means. Other people like the flat file database format, because it's simple, easily accessible from other programs, and it's easy to backup certain days or months of the database (since the filenames contain the date). Since ELOG should be independent of any other package, some "switchable" backend between native ELOG format and MySQL would be needed, which is lots of work and not planned right now.

   However, there are several contributions from other people who wrote scripts to put ELOG entries into a MySQL database. One is available at http://midas.psi.ch/elogs/Forum/387.

3. Can I run the ELOG daemon from inside Apache or any other Web server?

   No. The ELOG daemon was designed as a standalone server and it will stay like that in the future. The reason for that is that `elogd` should not rely on any other software. This is for example important for many people running `elogd` under Windows, and they have no clue how to install Apache for Windows. The installation and maintenance for `elogd` therefore becomes much simpler. To run `elogd` in parallel to an Apache server on port 80, use Apache as a proxy, following the instruction on the installation page ("Running elogd under Apache").

4. I can access my logbook without any password, isn't that a security problem?

   By default, no password is used in ELOG. This can be useful for public directories etc. that anybody should be able to read. To add password security, read the documentation under Access control. The recommended setup is password file security with guest access.

   Note that passwords are transferred over the network in plain text and therefore not secure. If this is a problem, a secure network connection should be used.

5. I want a bookmark pointing to the last page where an attribute has a certain value

   Use the URL:

   `http://<your.host>/<logbook>/?cmd=Last&<attribute>=<value>`

   This executes the "Last" command using a filter with <attribute>=<value>. The following command displays the same page, but also locks the attribute (checks the box next to <attribute>) so that browsing (next, previous, first, last) only shows pages with that attribute value.

   `http://<your.host>/<logbook>/?cmd=Last&<attribute>=<value>&l<attribute>=1`

   Note the "l" before the second attribute, as in "lAuthor=1".

6. I want a logbook with public read access (no password), but restricted write access

   In an old version of the FAQ it has been stated here that one has to use two logbooks pointing to the same data directory. From Version 2.0.6 on, this can be accomplished much easier by the usage of the "Guest menu command". Use a logbook with user level access (password file), and add menu lists like in the following example to the configuration file:

   `Menu commands = New, Edit, Reply, Find, Last 10, Change password, Logout, Help
   Guest menu commands = Find, Last 10, Login, Help
   `

   If users access the logbook without supplying a user name, they are treated like "guests" and see the "Guest menu commands", with which one cannot submit or edit logbook entries. If one hits the "login" button, a user can login with a user name/password and sees the normal menu commands, with which one can submit new logbook entries.

   An optional self registration is possible by specifying

   `Self register = 1`

   in the configuration file. New users can then create their own accounts.

7. I have many loogbooks with password files, so if I add a user or want to change a password I have to do this for all logbooks which is painful.

   You can have several logbooks point to the same password file. So if you change a user or password in that file, it becomes automatically available in all logbooks which use that file.

8. How can I configure ELOG such that it displays something else than the message list by default?

   There is a simple trick. You use the "Start page" option in the `elogd` file to redirect the start page to something else. Here are some examples:

       ?npp=5                                  for the last 5 messages
       ?last=7                                 show last 7 days (week)
       ?cmd=New                                show the new message entry form
       ?cmd=Find                               Show the "find" page
       ?cmd=Search&<attrib>=<value>            for a search with <attrib>=<value>

   The various URLs can be copied from the browser's address bar when doint various things there.

9. I want to have additional commands specific to my lookbook

   New commands can be added for example with the `"Bottom text = bottom.html"` option. To display all messages from last week and month of with "category = info", one can put following HTML code in bottom.html:

       <center>
       <a href="?last=7&Category=Info">Info from last week</a> |
       <a href="?last=31&Category=Info">Info from last month</a> |
       </center>

   Note that the parameters `"last=7&Category=Info"` applies a filter on the display. You can learn how to make these filters by looking at the URL in your browser when you submit a find command with certain options.

10. How does one configure elog to disable editing of existing messages? I want a logbook where one can enter messages but not change them afterwards.

    This works with the option `Menu commands`. By default, the menu commands `Back, New, Edit, Delete, Reply, Find, Config, Help` are dispalyed and allowed. To avoid editing (and deleting) of existing messages, one removes the two commands and puts following statement into `elogd.cfg`:

    `Menu commands = Back, New, Reply, Find, Config, Help`

    This prohibits the execution of the commands "Edit" and "Delete".

11. How can I track various revisions of a message using the "edit" command?

    There are two ways:

    - Add an attribute which keeps the revision dates and names as follows:

          Attributes = Author, ..., Revisions
          Locked attributes = Revisions
          Subst on Edit Revisions = $Revisions<br>$date by $long_name

      The "Revisions" attribute cannot be modified manually (since it's locked). On each edit, the date and the current author is appedned to the previous revisions. The "<br>" puts a line break between the entries.

    - Create a thread for each entry. In addition of having the date and author of different revisions, the message content is kept. To revise and entry, one hits "Reply" instead of "Edit" (one can disable the "Edit" command for example). If one puts following option into the configuration file:

          Reply string = ""

      then the reply contains the original message without the usual "> " at the beginning of each line. One can then edit the message and submit it. In the threaded message list display, one sees then the different revisions as a message thread.

12. How can I enter a date which is different from current one?

    Usually, the current date/time is recorded when you add a new entry. It might be, however, that one wants to enter "old" entries, or some entries with a date in the future (like a to-do list with a due date). To do that, on can add a new attribute (let's call it Record date, to be different from the pre-defined Date:

    `Attributes = Author, ..., Record date
    Type Record date = date
    Preset Record date = $date
    Date format = %Y %m %d
    List Display = Record date, Author, ...
    Start page = ?rsort=Record date
    `

    The Preset Record date statement sets the record date to the current date, but this can then of course edited during the message entry. The List Display and Start page statements show the record date as the first column in the summary display and also sort by that. Note the Date format showing first year, then month and day. This is necessary since sorting is done only lexically. Please note that the List Display was renamed recently. Prior to version 2.3.10, it was called Display Search.

13. I cannot pass the login page, it's always redisplayed even if I put in the right password?

    This can happen if you change the login policy, for example move the `Password file =` entry in the configuration file from a logbook section to the [global] section or back. In that case some old cookies could be stored in your browser, which confuse the system. Please delete your cookies in the browser to resolve this problem. Read your browser documentation on how to do that.

14. How can I change an attribute for an entire thread? We have an attribute "open problem/fixed" which should be changed for the whole thread if that problem has been fixed.

    This is a typical request of a bug-tracking set-up. Someone enters a request, opening a new thread. The expert(s) reply to the the request, and after a while, the request gets satisfied or the problem gets fixed. If an attribute like "status", having the options "open" and "fixed" could get changed for the whole thread, on could very easily search for all "open" problems.

    Since this functionality is not implemented, an alternative strategy is recommended: Implement two (or more) logbooks. The first logbook has open issues, the second one has fixed ones. When an entry changes state, it simply has to be copied to the second logbook. This can be done by defining the menu command "move" in the config file, like:

    `Menu commands = Back, New, Edit, Delete, Reply, Find, Move to, Config, Help
    `

    Note the additional Move to. This solution is even more elegant than having attributes changed in whole threads, since one has two separate logbooks, and can treat the second one more like an archive, make separate back-ups, or deleting some entries after some time, while keeping the open issues untouched.

15. Can I use RSS feeds with password protected logbooks?

    RSS feeds normally only work for logbooks which have at least public read access (via the guest menu commands). There is however a way to allow only restricted read access and still use RSS feeds. This is done by adding an additional read password via the `elogd -r <pwd> -l <logbook>` command. This password (username may be any) can then be used in an RSS reader for restricted access. One reader which has been successfully used with this kind of authentication is RSSReader.

16. How can I make a whole thread open or closed?

    Sometime people want to mark a whole thread in a way. An example is a to-do list, where they want a special icon on high priority things, and have this icon disappear one the task is finished. This can be easily done with icons. The configuration could look like this:

        Attributes = Author, Status, Subject
        IOptions Status = icon1.gif, icon2.gif, icon4.gif
        Preset Status = icon4.gif
        Preset on reply status = icon2.gif
        Icon comment icon1.gif = Closed entry
        Icon comment icon4.gif = Open entry
        Thread display = $Author $Subject
        Thread icon = Status

    New entries get an exclamation mark icon for example ("Preset status = ..."). Replies to this entry get a reply icon. Once the thread should be closed, one simple edits the top entry in that thread and changes the icon. The icon1.gif from the distribution is maybe not ideally suited for that, but one could make a green check mark icon for example for that. The "Thread display" and "Thread icon" make this icon appear at the left side of the threaded display.

    An alternative approach would be to use two logbooks. The first one receive all new entries ("open items"). Once an entry (with its replies) gets closed, it must be moved manually to the second logbook ("closed items"). This can be done with the "Move To" command (see "menu commands" in config file). This way one nicely separates open and closed items in two separate logbooks. One can still search both logbooks at the same time if one checks "Search all logbooks" in the find page.

    Starting from elog version 2.7.7, there now even a third way to do this. With an additional line in the configuration file: Collapse tn last = 1 (in fact the default, but to be explicit), then when the thread is ready to be marked as closed, select the "closed entry" icon when writing the last entry. When the entries are viewed in "threaded" mode, then the closed entry icon appears on the last entry; and when in "threaded, collapsed" mode, then the closed entry icon appears in the one line that represents that whole thread.

17. Does elog have a spell checker?

    No, but you can use any spell checker which works with your browser. Examples are IESpell for Internet Explorer and SpellBound for Mozilla-based browsers.

18. Why are entries with large attachments submitted so slowly?

    If email notifications are used, the ELOG program has to pass these attachments to the email server, which might take quite some time. Some email servers even don't allow to forward attachments if they are larger than a few mega bytes. In that one can simply turn off the forwarding of email attachments with

        Email format = 111

    this causes only the attachment names being forwarded, not the attachments themselves.

19. The elgod daemon crashes from time to time, what can I do?

    Bugs are constantly fixed inside elogd so a upgrade to the current version is recommended as a first measrue. If that does not help, the key will be the reproducibility of the crash. I only can fix problems if I can reproduce them. Sometimes it's related to strange logbook entries which cause elogd to crash when they are edited. So if there is a way to reproducible trigger the problem, I need the files and confiration related with it. If I can reproduce it in my local installation, I can fix it pretty soon.

    If that is not possible, an alternative is to run elgod under a debugger, and do a stack trace if the program dies. Under linux, this can be done using the gdb debugger, which might look like this:

        [~/elog]$ gdb ./elogd
        GNU gdb Red Hat Linux (6.5-25.el5rh)
        ...

        (gdb) run
        Starting program: /afs/psi.ch/user/r/ritt/elog/elogd
        elogd 2.7.5 built Dec  2 2008, 10:47:09 revision 2147
        ImageMagick detected
        Indexing logbooks ... test

        Program received signal SIGSEGV, Segmentation fault.
        0x08054beb in el_index_logbooks () at src/elogd.c:3892
        3892       *p = (char)1;
        (gdb) where
        #0  0x08054beb in el_index_logbooks () at src/elogd.c:3892
        #1  0x080b8774 in server_loop () at src/elogd.c:27565
        #2  0x080bbdd5 in main (argc=1, argv=0xbfee5b54) at src/elogd.c:28923
        (gdb)

    So the basic command is to make a stack trace with "where" after a segmentation fault. This tells me where in the code something wrong happened (in this case it was inside the function el_index_logbooks() at line 3892. Please send me this information and I will try then to figure out what was wrong.

20. How can I create an ELOG entry automatically from a script

    I agree, it's a bit hidden, but on the User's Guide, at the bootom of the page, last point, there is a description of the standalone "elog" utility, which can be used from a script or from another program to submit an automatic email entry. This works locally or remotely, with optional attachments. Enter "elog -h" for a full list of options. The elog utility is part of the distribution and resides in the same directory as the elogd daemon.

21. I want to notify different people for different things, how do I set up this?

    Assume you want to send an email notification to person A for a problem report, to person B for problem fix and so on. The simplest way is to use the `Email <attribute> <value> = <email address>` syntax. So you could set-up following configuration:

        Attributes = Author, Type
        Options Type = Problem Report, Problem Fix
        Email Type Problem Report = person.a@elog.com
        Email Type Problem Fix = person.b@elog.com

    If you want to select email addresses directly from a list, you can do the set-up as following: <pro> Attributes = Author, Notify MOptions Notify = Person A, Person B Email Notify Person A = person.a@elog.com Email Notify Person B = person.b@elog.com </pro> This way you can for each entry select one or more people to be notified from the pre-defined list.