Accessing an ELOG server and its logbook(s)
Usually you will be given a URL (through mail, a Web page etc.) to access the ELOG server.
If several logbooks are defined on the server, the entry page may be a list of all logbooks, with their descriptions and links to enter the logbook you want to use (this may be disabled).
Alternatively, you may be taken directly to a specific logbook. By default you will see the latest entry, but the administrator may have defined a different "default view" for the logbook, like the list of the day's entries, or the last 10 entries, etc. (depending on what is most convenient for that logbook's purpose).
Note : it is generally not recommended to link directly to a specific entry in a logbook by its URL, because under certain circumstances such addresses might change. It is possible to achieve the same result with a "search" URL (see below).
There are four ways through which access to a logbook may be controlled : it may be open for all to read ; it may require a common "read" password for all users ; it may require each user to have an individual user account (login name) and password ; finally, access may be granted or not depending on the address of the workstation you are using.
Adding stuff to a logbook
If you have "write access" to a logbook (by one of the same four methods as for read access), then you may use the "New", "Edit", "Reply" and "Delete" commands.
For the quality of the information committed to the logbook, you need understand and use these as well as possible. Here are some of the important features for each commmand :
- New :
- you will not be able to save your entry if all attributes marked with a red star (*) are not filled in.
- some attributes may be pre-filled from system variables (like your user name). Pre-filled attributes may be still editable or read-only (like the entry creation date).
- attributes may be text fields (limited to 100 characters), list-boxes (max. 100 values), or check-boxes. There is also a special type of attribute where several values are listed on a line with check-boxes, and you can check as many values as needed.
- a nice touch : URLs in attributes (http://..., ftp://..., mailto:...) are automatically converted to links.
- in addition to the above URLs, one can enter a tag elog:<id> which references another logbook entry. The tag elog:<logbook>/<id> references a message in another logbook on the same server.
- the Text multi-line field, if present, may be pre-filled with a template if entries need to have a common, consistent format across the logbook (especially for HTML). There may also be a comment inserted before it to explain local rules and conventions, upload rules, etc.
- check the "Submit as HTML" box if the entry contains HTML markup.
- a logbook may be configured to send a notification e-mail to various recipients each time an entry is submitted. This may be the default behaviour, and you should check "Suppress notification" if it is not wanted. Or it may be checked by default, and you need to explicitely uncheck it to send the mail. Then again, you may not have a choice... (note that notifiation recipients may or may not be disclosed).
- if the logbook allows attachments, there will be a number of fields with "Browse" buttons at the bottom of the form. Use these to pick one or more files on your local computer, they will be uploaded to the ELOG server as you submit the form. IMPORTANT : there is an upper limit on the size of individual attached files. By default it is about 1 MB but can be changed by the administrator.
- Edit :
- normally the Edit form will have all the values of the existing entry in its fields for modification. However, sometimes you may see fields that have been blanked if this makes sense for a particular logbook application (e.g. a "Last modified by" field).
- the "Submit as new entry" checkbox only appears on Edit forms. If it is unchecked, the modified entry keeps its original creation time-stamp. If it is checked, the modified entry becomes the latest in the logbook, as if it had just been created. Again, it is possible that this is checked by default, or disabled altogether on some logbooks.
- managing attachments through this form is easy. If all you want to change is the attributes or text, don't touch the fields at the bottom and the original attachments will be preserved. If you want to add an additional attachment, use an empty field. If you want to update an existing file, use the "Browse" button below that file's name to specify the new one. Lastly, if you want to delete an attachment without upoading a new one in its place, you must type the magic word "
<delete>
" in the field below its name.
- Reply :
- this command creates a new entry, but with the current entry's text "quoted" (with '>') in the compose form, much like when replying to e-mail.
- the new entry has a special "In reply to" attribute with a link to the original entry ; the latter also acquires a "Reply" attribute with a link to the new entry. Unfortunately these links cannot be trusted in the present ELOG storage system, and the whole scheme gets somewhat confusing when there are several replies.
- Delete :
- nothing much to say about this one, except that there is no "Recycle bin" or whatever : once you have confirmed the deletion of an entry, it's gone for good, so be careful ! (same holds for the replacement or deletion of an attached file).
Misc. tips & tricks, things to be aware of...
- as mentioned above, it is not recommended to link directly to a specific entry by its URL (from another entry or an external Web page). However, it is easy enough to achieve the same result with "search URLs" : use the "Search" form to compose a query that will result in exactly what you want (either a single entry or a list of entries). Copy the URL for that result page from your browser, and use that as the target for your link.
- right now you cannot search entries for attachments by their file name.
- right now attributes that consist of just a checkbox ("boolean") can only be searched by "checked" state in the "Search" form. However, if you start from an entry where that attribute is unchecked, you can use "filtered browsing" to flip through all other entries where it is also unchecked.
- as mentioned above, the "Reply" command only provides a basic comment/chat facility - a full-blown discussion board is not ELOG's purpose. If a logbook has a very specific purpose and format (picture gallery, event log, file library etc.) it might be a good idea to disable that command there and move all chat/comments/discussions to a separate, dedicated logbook to avoid "visual pollution".
- it is important to understand that currently the ELOG server application is "single-process" and "non-streaming". In normal terms this means that :
- only one request is processed at any one time by the server.
- uploading or downloading an attachement file is a single request, and causes the entire file to be loaded in server memory while the request is being processed.
This is not normally a problem for the sort of short, text-mode entries ELOG is designed to support. However, if a user starts to upload or download a large attachment file (or image) over a slow link, all other users on that ELOG server will have to wait for that transfert to finish before they can access any logbook on that server. This is why there is a low limit on the size of attachments, and why ELOG should not be used to distribute large files under intensive multi-user conditions.
- It is possible to use bookmarks to pre-populate various attributes when submitting an ELOG entry.
This can be useful if the same person often creates similar entries from the same PC. For example, with a bookmark of the form:
http://your.host/your_logbook/?cmd=New&pauthor=joe&ptype=Info
...a new entry is created, with the "author" field pre-populated with "joe" and the "Info" value preselected for the "type" field. The same is possible for any attribute defined in the logbook (note the leading "p"). Thus you can define a set of bookmarks for various types of logbook entries.
- In addition to submission of logbook entries through the Web interface, the
standalone "client" program
elog
can be used. The parameters
are:
elog -h hostname [-p port] [-l logbook]
[-w password]
[-u username password]
-a <attribute1>=<value1>
-a <attribute2>=<value2>
...
-f attachment1
-f attachment2
...
-m textfile | text
The password must match the write password defined on the server. If
user level access is defined on the server (via the "password file =" option),
a valid user name / password pair must be specified with the -u
option.
Multiple attributes can be specified as well as several attachments.
The message text can be supplied directly at the command line or submitted
from a file with the -m
flag.
The elog
program makes it possible to submit logbook
entries automatically by the system or from scripts. In some shift logbooks
this feature is used to enter alarm messages automatically into the logbook.