Content Management intern

1. Content Management intern

2. „CMS“ definition quotation:Unter Content Management wird die systematische und strukturierte Beschaffung, Erzeugung, Aufbereitung, Verwaltung, Präsentation, Verarbeitung, Publikation und Wiederverwendung von Inhalten (Content) informationstechnisch vorgehaltener Informationen verstanden. (Rothfuss/Ried „Content Management mit XML“2001)

3. Overview • CMS classification • WebCMS classification • WebCMS components in detail • Operating and migration considerations • mid size vs. enterprise CMS comparison • CMS customization example

4. CMS classification Typical cms groups are: • Website-CMS (WebCMS, WCMS) • Document Management Systems (DMS) • MAM (Media Asset Management Systems) • Portal Systems

5. WebCMS classificationby size / usage • Small systems ( „small-business“, „lite“ ) • Midsize systems • Huge systems („enterprise“)

6. CMS, technical viewenvironment, programming languages • Web Server • Programming Language • Database System • Content, Content Storage, Content Objects • Content Life Cycle • Rights Management • Content Output

7. Web Servers • Common Web Servers (i.e. Apache, IIS) are typically used as CMS environment • enterprise level CMS sometimes use own web servers which are dedicated to deliver database-held content • some CMS use application server environments (ColdFusion, ...)

8. Programming Languages • small and midsize CMS must integrate easily into common web environments. => common scripting languages are used • Use of new technologies such as J2EE enables building of large-scale eCMS

9. Databases • CMS must use common relational databases for easy setup and integration into existing environments • However, CMS content is mostly organized in object-oriented or XML-form => Content is mostly stored in RDBMS, but some CMS use their own or application server‘s mapping for (xml|oo)<->rdbms

10. Content • To achieve Separation of content and presentation , documents have to be split into small pieces, like media elements or text paragraphs. • this results in a hierarchical structure of content elements, with layout elements (i.e. html templates) corresponding to sets of content elements • The structure‘s depth varies among different CMS, typical depths are:- 1 (results in one big editor per page)- 2 („container“-based editing )- ∞ (object-oriented systems)

11. Content Life Cycle The content lifecycle consists of these 5 steps: • Creation / import • review / editing • validation • publishing • archiving (includes deletion) Every CMS implements these steps, although some systems combine some of them into one workflow step.

12. Rights Management • applies to multi-user CMS • content elements and/or hierarchical elements (i.e. folders) can be assigned access rights • typically rights are split into create / modify / publish / delete [ / rights manage ] rights. • easy system setup can be achieved with preconfigured roles.

13. Output • Staging the CMS‘s renderer ist not accessible from the internet, web pages are therefore delivered to a normal web server. The user accesses a static export of the web site. • Live Rendering The requested web pages are rendered on the fly and directly delivered from the CMS to the user.

14. staging vs. live rendering IStaging + Good performance, as only normal html-pages are delivered. Especially no database bottlenecks + good scalability because the static web site exports can easily be replicated to other servers + high security because the CMS can never be compromised • can only manage „normal“ web sites, cannot manage dynamic pages (i.e. forums, communities, feedback forms, personalization) • content can be updated only in configured intervals • CMS cannot help with web site statistics

15. staging vs. live rendering IILive Rendering + Possibility to maintain full-scale Web Applications / dynamic Web Sites + detailed statistics possible (i.e. click paths) • low performance, especially for sripting language CMS • scalability hard to establish • additional security measures must be established in order to guard the CMS

16. Content Import, Export • Content migration between most CMS is nearly impossible because of fundamental differences in the content hierarchy • list-based im-/export of content fragments (articles, container) is often possible • xml-based formats are commonly used for lossless export of DB-held content

17. Export considerations these content groups can be exported and may be imported in another System: • Pages (page hierarchy) • Page Contents (to be imported as separate Containers in case of different content storage hierarchies) • Ressources (Media Assets) • User / Group / Role Lists

18. Interfacesexternal databases There are two ways of accessing external DBMS from cms: • direct acces via template programmingCode to access the DB is directly placed in template, and is executed during the rendering process (live cms) or on the staging web server • access through data source abstractiondata source is defined to the CMS‘s abstraction layer and can afterwards be accessed with common CMS functions

19. InterfacesContent Syndication • Content Syndication means considering (own) content (-elements) as assets which can be used in different web sites • CMS can assist in delivering content to other web sites or integrating external content • xml-based formats for article import and export exist, for example NITF

20. CMS, technical viewexample I

21. CMS, technical viewExample II

22. Customization ExampleAdding external user authentication Two strategies to use external user databases for CMS: • Periodically import user/group information from external sources • Drop internal user management, directly use external source instead for all requests

23. LDAPLeightweight Directory Access Protocol LDAP: Access protocol for directory service databases (X.500) defined in RFC1777 Directory Service: • Database for attribute-based records (name-value pair lists) • Record groups are organized in trees

24. LDAPTest Setup This .ldif-File represents one x.500-entry for testing purposes. The original object class InetOrgPerson has been extended by cms-specific fields hans_meiser.ldif: dn: mail=hans@test.de,o=test,c=de,dc=de objectclass: MyInetOrgPerson cn: Hans Meiser mail: hans@test.de uid: hans passwd: geheim cmsgroup: user sn: nix telephoneNumber: 01234 / 5678 -90

25. WCMS user authentication • using Web-based CMS means requesting independent web pages • web page context is a common Session, identified by a session id • When a user logs in with username and password, his user data and rights info are added to the current session object. • User authentication means: session_id, username and password in, userdata-added session or user_id from which data is to add out.

26. <? /* External user authentication API in: $username byref in: $password (plain) byref out: $valid = 0|1 out: $uid (system_user PK) */ // Example: Call external program to validate user $cmd = "(echo \"$username\"; echo \"$password\") | /home/sayn/pwtest"; $p = popen($cmd, 'r'); while( !feof($p) ) $ret .= fread($p, 1024); pclose($p); $ret = explode( "\n", $ret ); if( $ret[0] != 'OK' ) { $valid = 0; } else { // Search for given username in CMS user DB $all = db_query( "SELECT * FROM system_user WHERE username=\"$username\"" ); if( $row = mysql_fetch_assoc( $all ) ) { if( $row['disabled'] ) { // found but disabled? Login not allowed! $valid = 0; } else { // user found, return user_id $uid = $row['id']; } } else { // Username is valid but not known in local DB: // insert user record. // Password remains empty => login without external authentication will not be possible db_query( "INSERT INTO system_user " . "SET username=\"$username\", realname=\"$username\", created=NOW()" ); $uid = mysql_insert_id( ); db_query( "INSERT INTO system_user2group SET user=$uid, in_group=1" ); } $valid = 1; } WCMS User AuthenticationExample Code Fragment

27. WCMS User Authenticationusing LDAP // Example: lookup userdata in ldap directory $ds=ldap_connect("localhost", 389); ldap_set_option($ds, LDAP_OPT_PROTOCOL_VERSION, 3) // Set PRotocol to LDAPv3 $r=ldap_bind($ds); // anonymously bind for read-only access // Lookup username in directory // in this example, users should log in with their email address $sr=ldap_search($ds, "o=test, c=de, dc=de", "mail=$username"); // Authentication is only possible if search returned one item if( ldap_count_entries($ds, $sr) != 1 ) { $valid = 0; } else { $info = ldap_get_entries($ds, $sr); $username = $info[0]['uid'][0]; // plain text password comparison. Remember, this is just an example if( ( $password=='' ) || ( $password != $info[0]['passwd'][0] ) ) { $valid = 0; } else { ...

28. other LDAP integration • associate user groups to ldap subtrees • use host system user authentication as abstraction (see example 1) • certificate-based authentication (user logs on with ....)