Why not use a tree to store routing addresses? As shown in the figure, each box is a Map When you request /user/111/profile/books/222, break up the url first ['/', '111', 'profile', 'books', '222'] First search if there is a / node on the first layer Then search if there is a 111 node on the second layer, if not enter the * node Then search the third layer Does the layer have a profile node and so on
The flexibility shown by regex in routing is difficult to replace by other technologies. You can also use regular rules to optimize performance. The principle is very simple. Combine regular rules and use a certain strategy to determine which one is based on the regular matching results
For example, there is
/user/{pid}/profile
/news
/product/{pid}
/product/{pid}/comment/{cid}
Four routes
Use a regular #^(?|/user/(d+)/profile|/news|/product/(d+)()|/product/(d+)/comment/(d+)())$# to match
When the capture results include 1, 0, 2, and 3 groups respectively, we know that the 1st to 4th routes have been matched respectively. By automatically merging regular expressions through some code and assigning the number of capture groups => routing mapping, multiple regular expressions can be merged together for one match
Here is a trick to use (?|) to reset the capture group
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Why not use a tree to store routing addresses?
As shown in the figure, each box is a Map
When you request /user/111/profile/books/222, break up the url first
['/', '111', 'profile', 'books', '222']
First search if there is a / node on the first layer
Then search if there is a 111 node on the second layer, if not enter the * node
Then search the third layer Does the layer have a profile node
and so on
https://github/bephp/router
This project does not use regular expressions, but cuts the URL according to "/" and saves it into a tree structure.
When mapping routes, it is equivalent to traversing the tree, and the complexity is O (log n).
The project is implemented in PHP, but the code is very small. It should be easy to understand.
Why can't we maintain a routing Dict? The value is the func corresponding to the key
The flexibility shown by regex in routing is difficult to replace by other technologies. You can also use regular rules to optimize performance. The principle is very simple. Combine regular rules and use a certain strategy to determine which one is based on the regular matching results
For example, there is
/user/{pid}/profile
/news
/product/{pid}
/product/{pid}/comment/{cid}
Four routes
Use a regular
#^(?|/user/(d+)/profile|/news|/product/(d+)()|/product/(d+)/comment/(d+)())$#to matchWhen the capture results include 1, 0, 2, and 3 groups respectively, we know that the 1st to 4th routes have been matched respectively. By automatically merging regular expressions through some code and assigning the number of capture groups => routing mapping, multiple regular expressions can be merged together for one match
Here is a trick to use
(?|)to reset the capture groupReference http://nikic.github.io/2014/0...