Webmastering Basics: Building and Maintaining Websites with Thomas Krichel

1. LIS901N: webmastering I: the static web site Thomas Krichel 2003-01-11

2. Structure of talk • First talk about me • My concepts of webmastering • Then talk about you • Introduction to wotan • basic manipulation of wotan • files • permissions • basic command • editing • creating your first page

3. About me • Born 1965, in Völklingen (Germany) • Studied economics and social sciences at the Universities of Toulouse, Paris, Exeter and Leiceister. • PhD in theoretical macroeconomics • Lecturer in Economics at the University of Surrey 1993 and 2001 • Since 2001 assistant professor at the Palmer School

4. Why? • During research assistantship period, (1990 to 1993) I was constantly frustrated with difficult access to scientific literature. • At the same time, I discovered easy access to freely downloadable software over the Internet. • I decided to work towards downloadable scientific documents. This lead to my library career (eventually).

5. Steps taken I • 1993 founded the NetEc project at http://netec.mcc.ac.uk, later available at http://netec.ier.hit-u.ac.jp as well as at http://netec.wustl.edu. • These are networking projects targeted to the economics community. The bulk is • Information about working papers • Downloadable working papers • Journal articles were added later

6. Steps taken II • Set up RePEc, a digital library for economics research. Catalogs • Research documents • Collections of research documents • Researchers themselves • Organizations that are important to the research process • Decentralized collection, model for the open archives initiative

7. Steps taken III • Co-founder of Open Archives Initiative • Work on the Academic Metadata Format • Co-founded rclis, a RePEc clone for (Research in Computing, Library and Information Science)

8. Webmaster • There are two available definitions that come to mind • A webmaster is a person who has write access to a set of files that are available for display on the World Wide Web. • A webmaster is a person who has control over a software installation that can deliver web pages. • The second is more stricter. We mostly use the first one.

9. Webmastering • Webmastering combines many aspects: • Work on the organization of data to fit onto pages • Set display style of different pages • Organize the contribution of data • Maintain a technical web installation • Some of them can be learned in a course, but others can not. • Emphasis has to be on learnable elements.

10. Teaching philosophy • Point and click on a computer software is not enough. • Explain underlying principles. • Promote standards. • Avoid proprietary software.

11. Webmastering I • Deals with the maintenance of a static web site. Such a web site remains the same whatever the user does with it. • Topics include • html • http • information architecture • web server

12. Webmastering II • Deals with building dynamic web sites. • Users fill in a form • Users submit the form • Web server return a page that is specific to the request of the user. • Teaches a language called PHP, that is widely used to generate such web sites. • Gets you introduced to computer programming • Gets you to train analytical thinking.

13. Webmastering III • Deals with XML • XML is a syntax to encode any kind of data. • XML can be constrained to only allow certain types of data (XML Schema) • XML can be transformed to render the data in various ways (XSLT) • Achieve a separation of contents and presentation of a web page. • advanced course, has both Schema and Transformation

15. Free software • I maintain the server but • if • you have Internet access • you have an old PC you could build the server yourself. The server as well as putty and winscp are free software. I will not now elaborate more on the nature of free software.

16. Communication with the server • For file editing and manipulation, we use putty. • For file transfer, we use winscp. • Both are available on the web. • Telnet and ftp servers are not available on wotan. Telnet and ftp do not encrypt the communication stream and therefore they are not secure. • The protocol is ssh, the secure shell, based public-key cryptography.

17. Installing putty and winscp • Go to your favorite search engine to search for putty. • Download and save putty. • Leave your computer if it does not allow you to do it. • Do the same thing with winscp

18. Debian • Is a distribution of free software that provides an operating system and application programs • Named after Deborah and Ian Jackson • Uses the Linux kernel, but could run with other kernels • Uses mainly GNU software, based on work to write a free version of UNIX • Therefore also called Debian GNU/Linux • Wotan runs the “testing” version of Debian, codenamed sarge. • Usually the software is updated once a week. Let us do it now.

19. Registration Time • As part of the course, you are being provided with web space on the server wotan.liu.edu, at the URL http://wotan.liu.edu/~username where username is a user name that you can chose. • It is my intention to maintain this web space for you into the foreseeable future. • You should also choose a password, now. • I will now register you.

20. Login time • Use putty, port 22 to wotan.liu.edu • set other attributes of the session as you like, using the menu on the left, for example • colors • font shapes and sizes • bell • Save the session as “wotan” (in the first screen) to save all the customization. • Do the same thing at home!

21. Files, directories and links • Files are continuous chunks data on disks that are required for software applications. • A link is a file that contain the address of another file. Microsoft call it a shortcut. • Directories are files that contain other files. Microsoft calls them folders. • In UNIX, the directory separator is “/” • The top directory is “/” on ist own.

22. Home directory • When you first log in to wotan you are placed in your home directory /home/username • “cd” is the command that gets you back to the home directory. • The home directory is also abbreviated as “~“ • cd ~user gets you to the home of user user. • “cd ~” does what?

23. ~/public_html • Is your web directory. You create it with “mkdir public_html” in your home directory. • The web server on wotan will map requests to http://wotan.liu.edu/~user to show the file ~user/public_html/index.html • The web server will map requests to http://wotan.liu.edu/~user/file to show the file ~user/public_html/file • The server will do this by virtue of a configuration option.

24. changing directory, listing files • cd directory changes into the directory directory • the current directory is “.” • its parent directory is “..” • ls lists files • As an exercise, move around the directory structure and discover the files that they hold with ls. • IMPORTANT NOTE: bash allows completion of file and directory names with the TAB character

25. issuing commands • While you are login, you talk to the computer by issuing commands. • Your commands are read by command line interpreter. • The command line interpreter is called a shell. • You are using the Bourne Again Shell, bash. • bash allows to browse the command history with the arrow keys • bash allows to edit commands with the arrow keys • exit is the command to leave the shell.

26. Users and groups • “root” is the user name of the superuser. • The superuser has all privileges. • There are other physical users, i.e. persons using the machine • There are users that are virtual, usually created to run a daemon. For example, the web sever in run by a user www-data. • Arbitrary users can be put together in groups.

27. Permission model • Permission of files are given • to the owner of the file • to the the group of the file • and to the rest of the world • A group is a grouping of users. Unix allows to define any number of groups and make users a member of it. • The rest of the world are all other users who have access to the system. That includes www-data!

28. Listing files • ls lists files • ls –l make a long listing. It contains • elementary type and permissions (see next slide) • owner • group • size • date • name

29. First element in ls -l • Type indicator • d means directory • l means link • - means ordinary file • 3 letters for permission of owner • 3 letters for permission of group • 3 letters for permission of rest of the world • r means read, w means write, x means execute • Directories need to be executable to get in them…

30. Change permission: chmod • usage: chmod permission file • file is a file • permisson is three numbers, for owner, group and rest of the world. • Each number is sum of elementary numbers • 4 is read • 2 is write • 1 is excute • 0 means no permission. • Example: chmod 764 file

31. General structure of commands • commandname –flag --option • Where commandname is a name of a command • flag can be a letter • Several letters set several flags at the same time • An option can also be expressed with - - and a word, this is more user-friendly than flags. • Let us look at an example with the ls command.

32. example • ls lists files • ls -l makes a long listing • ls -a lists all files, not only regular files but some hidden files as well • all files that start with a dot are hidden • ls -la lists all files is long listing • ls --all is the same as ls -a. --all is known as a long listing.

33. Copying and removing • cp file copyfile copies file file to file copyfile. If copyfile is a directory, it copies into the directory. • mv file movedfile moves file file to file movedfile. If movedfile is a directory, it moves into the directory. • rm file removes file,there is no recycling bin!!

34. Directories and files • mkdir directory makes a directory • rmdir directory removes an empty directory • rm -r directory removes a directory and all its files • more file • Pages contents of file, no way back • less file • Pages contents of file, “u” to go back, “q” to quit

35. file transfer • you can use winscp to upload and download files to wotan. • If uploaded files in the web directory remain invisible, that is most likely a problem with permission. Refer back to permissions. • chmod 644 * will put it right for the files • chmod 755 . (yes with a dot) will put it right for the current directory • * is a wildcard for all files. • rm -r * is a command to avoid.

36. editing • There are a plethora of editors available. • For the neophyte, nano works best. • nano file edits the file file. • nano -w switches of line wrapping. • nano shows the commands available at the bottom of the screen. Note that ^letter, where letter is a letter, means pressing CONTROL and the letter letter at the same time.

37. your first page • cd • mkdir public_html • cd public_html (do cd pu<TAB>) • nano index.html • edit your file • find your file on the web with a web browser. • You have written your first web page! • but your page is not likely to comply with rules of html!

38. Copy and paste • Putty allows to copy and paste text between windows and UN*X. • On the windows machine, it uses the windows approach to copy and paste • On the UN*X machine, • you copy by highlighting with the mouse’ left button • you paste using the middle button

39. http://openlib.org/home/krichel Thank you for your attention!