Novell Documentation: Volera Excelerator 2.3 - How URL Masks Are Processed

How URL Masks Are Processed

You can enter four basic types of URL masks in the pin list. The following table lists each type, provides a few examples of each, and provides information on how they are processed by Excelerator.

Type	URL Mask Examples by Specificity	Notes
Hostname	http://www.foo.gov/documents/picture.gif http://www.foo.gov/documents/ http://www.foo.gov/ foo.gov/documents/ foo.gov/ *.foo.gov/	Although these entries can include the protocol or scheme, the DNS name, the path, and the filename, only the DNS name or hostname must be present in the mask. All DNS label portions must be indicated, if only by an asterisk wildcard. Excelerator processes hostname entries before it processes other mask types. It also processes the most specific URL mask entries first. When an object match occurs, Excelerator applies the pin type rule, and processing of the object is finished. For example, if the first URL mask in the examples column has a pin type rule of bypass, picture.gif will not be cached regardless of the pin type rules for the other URL masks. Hostname entries can have a dramatic impact on object pinning and cache bypassing. For example, if the first two URL masks in the examples column were not present, a pin type of Bypass on the third URL mask would prevent caching of all objects delivered through HTTP on the www.foo.gov Web site. If no scheme (HTTP, FTP, etc.) is indicated, the mask applies to all schemes. The last three masks would apply to objects delivered through any Web protocol. Finally, Excelerator interprets hostnames literally. For example, the sixth entry would cover www.foo.gov, ww1.foo.gov, army.foo.gov, etc., but the fourth and fifth entries would not, because a scheme is assumed to immediately precede the hostname.
Path	/documents/picture.gif /documents/picture.gif/ /documents/	Excelerator processes path entries after all hostname entries have been considered. It assumes that the first forward slash immediately follows a hostname. For example, the first entry would apply only to a graphics file named PICTURE.GIF that is located in a DOCUMENTS directory at the root of the host. The forward slash in the second entry causes Excelerator to assume that PICTURE.GIF is a directory. The pin type rules associated with this entry would apply to any matched objects that have a URL directory path that starts with a documents directory followed by a subdirectory named PICTURE.GIF. The third entry would apply to any matched objects that contain a DOCUMENTS directory at the start of their URL paths.
Filename	/picture.gif /widget.js /default.htm	After the path entries have all been processed, Excelerator looks for specific filenames. For example, if requested objects named PICTURE.GIF, WIDGET.JS, and DEFAULT.HTM have not been covered by one of the hostname or path entries above, the files will have the pin type rule for their respective filename mask applied to them. If the first entry carries a pin type rule of Bypass, all PICTURE.GIF files that didn't match previously processed hostname or path masks would not be cached.
File Extension	/.gif /.js /*.htm	File extension entries are processed last. These are simply filename entries with the root of the filename replaced by an asterisk, which makes them less specific than complete filenames. For example, if the examples shown all had pin types of Bypass, then only those .GIF, .JS, and .HTM files that had been cached and pinned because of hostname, path, or filename masks would be stored in cache. All other files with the named extensions would not be cached.

Type

URL Mask Examples by Specificity

Notes

Hostname

http://www.foo.gov/documents/picture.gif

http://www.foo.gov/documents/

http://www.foo.gov/

foo.gov/documents/

foo.gov/

*.foo.gov/

Although these entries can include the protocol or scheme, the DNS name, the path, and the filename, only the DNS name or hostname must be present in the mask. All DNS label portions must be indicated, if only by an asterisk wildcard.

Excelerator processes hostname entries before it processes other mask types. It also processes the most specific URL mask entries first.

When an object match occurs, Excelerator applies the pin type rule, and processing of the object is finished.

For example, if the first URL mask in the examples column has a pin type rule of bypass, picture.gif will not be cached regardless of the pin type rules for the other URL masks.

Hostname entries can have a dramatic impact on object pinning and cache bypassing.

For example, if the first two URL masks in the examples column were not present, a pin type of Bypass on the third URL mask would prevent caching of all objects delivered through HTTP on the www.foo.gov Web site.

If no scheme (HTTP, FTP, etc.) is indicated, the mask applies to all schemes. The last three masks would apply to objects delivered through any Web protocol.

Finally, Excelerator interprets hostnames literally. For example, the sixth entry would cover www.foo.gov, ww1.foo.gov, army.foo.gov, etc., but the fourth and fifth entries would not, because a scheme is assumed to immediately precede the hostname.

Path

/documents/picture.gif

/documents/picture.gif/

/documents/

Excelerator processes path entries after all hostname entries have been considered. It assumes that the first forward slash immediately follows a hostname.

For example, the first entry would apply only to a graphics file named PICTURE.GIF that is located in a DOCUMENTS directory at the root of the host.

The forward slash in the second entry causes Excelerator to assume that PICTURE.GIF is a directory. The pin type rules associated with this entry would apply to any matched objects that have a URL directory path that starts with a documents directory followed by a subdirectory named PICTURE.GIF.

The third entry would apply to any matched objects that contain a DOCUMENTS directory at the start of their URL paths.

Filename

/picture.gif

/widget.js

/default.htm

After the path entries have all been processed, Excelerator looks for specific filenames.

For example, if requested objects named PICTURE.GIF, WIDGET.JS, and DEFAULT.HTM have not been covered by one of the hostname or path entries above, the files will have the pin type rule for their respective filename mask applied to them.

If the first entry carries a pin type rule of Bypass, all PICTURE.GIF files that didn't match previously processed hostname or path masks would not be cached.

File Extension

/*.gif

/*.js

/*.htm

File extension entries are processed last.

These are simply filename entries with the root of the filename replaced by an asterisk, which makes them less specific than complete filenames.

For example, if the examples shown all had pin types of Bypass, then only those .GIF, .JS, and .HTM files that had been cached and pinned because of hostname, path, or filename masks would be stored in cache. All other files with the named extensions would not be cached.