forward URI with manipulation

This is actually easier than it sounds. You can use the standard TCL string command (Click here) to extract everything including and past the second slash. Then use the HTTP::uri command to change the URI. I'm sure there are other ways to do this but this should work for you.

 

 

Also, In 9.x we support elseif's which should make your code a bit cleaner.

 

 

when HTTP_REQUEST {
   strip first directory from uri.
   ie. /foo/bar/foobar.ext -> /bar/foobar.ext
  set sub_uri [string range [HTTP::uri] [string first {/} [HTTP::uri] 1] end]
  if { [HTTP::uri] starts_with "/sales" } {
     pool sales_pool
     HTTP::uri $sub_uri
  } elseif { [HTTP::uri] starts_with "/cs" } {
     pool cs_pool
     HTTP::uri $sub_uri
  } else {
      do something else
  }
}

 

 

Here are the docs for the string commands I'm using.

 

 

string first string1 string2 ?startIndex?

 

Search string2 for a sequence of characters that exactly match the characters in string1. If found, return the index of the first character in the first such match within string2. If not found, return -1. If startIndex is specified (in any of the forms accepted by the index method), then the search is constrained to start with the character in string2 specified by the index.

 

 

string range string first last

 

Returns a range of consecutive characters from string, starting with the character whose index is first and ending with the character whose index is last. An index of 0 refers to the first character of the string. first and last may be specified as for the index method. If first is less than zero then it is treated as if it were zero, and if last is greater than or equal to the length of the string then it is treated as if it were end. If first is greater than last then an empty string is returned.

 

 

Here's a break down of the command

 

 

set sub_uri [string range [HTTP::uri] [string first {/} [HTTP::uri] 1] end]

 

 

is equivalent to:

 

 Find index of first slash searching from position 1 (2nd char)
set idx [string first {/} [HTTP::uri] 1]
 Get substring from uri starting at location of second slash to the end
set sub_uri [string range [HTTP::uri] $idx end]

 

 

just without the overhead of the temporary variable.

 

 

It shouldn't be necessary to check the return value of the string first command because it will return -1 if the uri doesn't have a second slash and then the subsequent string range command will return the entire string.

 

 

I'll leave it to others to post alternate implementations.

 

 

Good luck!

 

 

-Joe

Thanks Joe. There is a minor issue with the URI manipulation. Below both URL should have the first directory removed, but only the second works.

http://www.abc.com/sales

http://www.abc.com/sales/

More, if the server page has absolute path eg

....
....

the "ink href" and "img src" will not be accessible, since user need to access with "/sales" pre-pended. Is there any way to modify the server page data to insert the first directory?

Ok, you didn't mention that you needed the directory truncated if there wasn't a second slash. My previous example assumed that if there was only one directory, then it would remain.

 

 

Here's some code that should do the trick

 

 

when HTTP_REQUEST {
  set idx [string first {/} [HTTP::uri] 1]
  if { $idx != -1 } {
    set sub_uri [string range [HTTP::uri] $idx end]
  } else {
    set sub_uri {/}
  }
  ...
  HTTP::uri $sub_uri
}

 

 

This should result in the following transformations

 

 

/foo -> /

 

/foo/ -> /

 

/foo/bar -> /bar

 

/foo/bar.html -> /bar.html

 

 

 

Now, if you need to modify the response content to "re-add" your prefixes, we've covered this before. Check out my iRules entries on my blog

 

 

http://devcentral.f5.com/weblogs/joe/category/27.aspx?Show=All

 

Click here

 

 

Check out the "modify uri and rewrite" entry. I think that has what you are looking for.

 

 

Also, with 9.2 you can use the stream profile to accomplish the same thing in a more efficient manner.

 

 

-Joe

Sorry that I can't find the item "modify uri and rewrite" in the list. Can you give me more details? Thansk.

I'm pretty sure Joe was talking about this post to his blog:

 

 

Click here - modify uri and response

 

 

-Colin

I think the one we can use is the last one with "RESPONSE_DATA".

However as you can see that the http data doesn't contain the FQDN, it just contain a root, like "link href" and "img src" below

........

it is too risky to replace all "/ to "/sales/

more, by search and replace we may miss some cases like composed in javascript ...

any idea?

The example I provided does replace the FQDN and not the URI, but the concept is the same. Basically all we can do within the response data is do straight string replacement. You can do some smart parsing with the content looking for link, img, a, etc elements and then look for the corresponding href's or src's. Then extract the contents within. Basically if you get to this point you are building your own HTML parser within iRules which will more than likely be a big performance hog.

 

 

Unless you know a full list of strings to look for that you are going to change, it's going to be difficult to make it fool proof.

 

 

Good luck and let us know how it goes...

 

 

-Joe