Can someone give me an example when to use [L] flag? I'm learning about mod_rewrite moudle in .htaccess file and can't find out when to this flag.
The L flag simply means to stop applying any rules that follow. Given the same URL, http://example.com/foo/bar?q=blah, and given the rules:
RewriteRule ^foo -
RewriteCond %{REQUEST_URI} !^/bar.php
RewriteRule ^(.*)$ /bar.php?z=$1
The first rule gets applied and the URI gets passed through unchanged (via the - target). The rewrite engine then processes the next rule, and the URI gets rewritten to /bar.php?z=foo/bar. What happens when you add an L to the end:
RewriteRule ^foo - [L]
RewriteCond %{REQUEST_URI} !^/bar.php
RewriteRule ^(.*)$ /bar.php?z=$1
The URL http://example.com/foo/bar gets passed through untouched from the first rule, then stops because of the L flag. If the URL is http://example.com/something/else then the first rule doesn't match and the second rule gets applied, rewriting the URI to: /bar.php?z=something/else
Note that since the rewrite engine loops through all the rules until the URI stops changing, the L flag will not prevent the looping, only any further rules from getting applied in the current iteration.
Related
This is what's inside the .htaccess file:
RewriteEngine on
RewriteCond %{HTTP_HOST} ^(.*)\.domain\.com
RewriteRule ^(.*)$ Subdomains/%1/$1 [L,NC,QSA]
When I'm on the domain (eg: x.example.com), it displays error 500. What am I doing wrong?
Example:
x.example.com -> show example.com/Subdomains/x but keep the URL of x.example.com
y.example.com -> show example.com/Subdomains/y but keep the URL of y.example.com
z.example.com -> show example.com/Subdomains/z but keep the URL of z.example.com
RewriteCond %{HTTP_HOST} ^(.*)\.example\.com
RewriteRule ^(.*)$ Subdomains/%1/$1 [L,NC,QSA]
Without any other directives to prevent it, the above will result in an internal rewrite loop, which will result in a 500 Internal Server Error response to the browser.
For example, if you request https://sub.example.com/foo then...
Request is rewritten to /Subdomains/sub/foo.
In a directory context (ie. htaccess) the rewriting process starts over, passing /Subdomains/sub/foo as in the input to the next round of processing...
Request is rewritten to /Subdomains/sub/Subdomains/sub/foo.
The rewriting process starts over...
Request is rewritten to /Subdomains/sub/Subdomains/sub/Subdomains/sub/foo.
The rewriting process starts over...
etc. until the server gives up. (Default is after 10 internal rewrites.)
The L flag does not stop all processing in a directory context (ie. htaccess). It simply stops the current round of processing. The rewrite process continues until the URL passes through unchanged.
The quick fix on Apache 2.4 is to simply replace the L flag with END. This causes all processing to stop. No further passes through the rewrite engine occur.
For example:
RewriteCond %{HTTP_HOST} ^(.*)\.example\.com
RewriteRule (.*) Subdomains/%1/$1 [END]
The NC and QSA flags are superfluous here.
Note that the regex ^(.*)\.example\.com matches any number of sub-subdomains, including www itself, if that is a concern?
Without using the END flag (Apache 2.4) then you would need to explicitly check that you have not already rewritten the URL. One way is to prevent any further rewrites if /Subdomains/.... has already been requested:
RewriteCond %{HTTP_HOST} ^(.*)\.example\.com
RewriteRule ^((?!Subdomains/).*)$ Subdomains/%1/$1 [L]
Note that if you have another .htaccess file located in the /Subdomains/<sub> subdirectory that also uses mod_rewrite then this will have also prevented a rewrite loop since mod_rewrite directives are not inherited by default.
UPDATE: Is there a way to check if the folder dosent exist then just redirect to domain.com?
Yes, you can do this, for example:
# If subdomain does not map to a subdirectory then redirect to root of main domain
RewriteCond %{HTTP_HOST} ^(.*)\.(example\.com)
RewriteCond %{DOCUMENT_ROOT}/Subdomains/%1 !-d
RewriteRule ^ https://%2/ [R=302,L]
# Otherwise, internally rewrite the request to subdirectory (if not already)
RewriteCond %{HTTP_HOST} ^(.*)\.example\.com
RewriteRule ^((?!Subdomains/).*)$ Subdomains/%1/$1 [L]
However, this is arguably detrimental to your users. A custom 404 response might be preferable.
I am new to .htaccess and I don't understand it well. Recently I have built the following code:
RewriteEngine On
RewriteCond %{HTTP_HOST} (.*)
RewriteCond %{REQUEST_URI} /api/v2/
RewriteRule ^api/v2(.*) /api/v2/api.php?input=$1
This was in the root public folder (example.com/.htaccess). But now I have to create second Rewrite and I want to make .htaccess file in example.com/api/v2/ folder. I tried to remove /api/v2/ part in each Rewrite Rule, but only thing I got was error 500.
What I want to achieve:
If someone uses this link: https://example.com/api/v2/test/test/123, I'd like to make it into https://example.com/api/v2/api?input=test/test/123 with .htaccess located in example.com/api/v2 folder.
Addressing your existing rule first:
RewriteCond %{HTTP_HOST} (.*)
RewriteCond %{REQUEST_URI} /api/v2/
RewriteRule ^api/v2(.*) /api/v2/api.php?input=$1
The first RewriteCond (condition) is entirely superfluous and can simply be removed. The second condition simply asserts that there is a slash after the v2 and this can be merged with the RewritRule pattern. So, the above is equivalent to a single RewriteRule directive as follows:
RewriteRule ^api/v2(/.*) /api/v2/api.php?input=$1 [L]
This would internally rewrite the request from /api/v2/test/test/123 to /api/v2/api.php?input=/test/test/123 - note the slash prefix on the input URL parameter value.
However, unless you have another .htaccess file in a subdirectory that also contains mod_rewrite directives then this will create a rewrite loop (500 error).
Also note that you should probably include the L flag here to prevent the request being further rewritten (if you have other directives).
If someone uses this link: https://example.com/api/v2/test/test/123, I'd like to make it into https://example.com/api/v2/api?input=test/test/123 with .htaccess located in example.com/api/v2 folder.
I assume /api? is a typo and this should be /api.php?. Note also that the slash is omitted from the start of the URL parameter value (different to the rule above).
I tried to remove /api/v2/ part in each Rewrite Rule, but only thing I got was error 500.
This is the right idea, however, you need to be careful of rewrite loops (ie. 500 error response) since the rewritten URL is likely matching the regex you are trying to rewrite.
Try the following instead in the /api/v2/.htaccess file:
RewriteEngine On
RewriteCond %{REQUEST_URI} !api\.php$
RewriteRule (.*) api.php?input=$1 [L]
The preceding RewriteCond directive checks that the request is not already for api.php, thus avoiding a rewrite loop, since the pattern .* will naturally match anything, including api.php itself.
You could avoid the additional condition by making the regex more specific. For example, if the requested URL-path cannot contain a dot then the above RewriteCond and RewriteRule directives can be written as a single directive:
RewriteRule ^([^.]*)$ api.php?input=$1 [L]
The regex [^.]* matches anything except a dot, so avoids matching api.php.
Alternatively, only match the characters that are permitted. For example, lowercase a-z, digits and slashes (which naturally excludes the dot), which covers your test string test/test/123:
RewriteRule ^([a-z0-9/]*)$ api.php?input=$1 [L]
Or, if there should always be 3 path segments, /<letters>/<letters>/<digits>, then be specific:
RewriteRule ^([a-z]+/[a-z]+/\d+)$ api.php?input=$1 [L]
I have to types of urls. The first one contains number and the second does not, e.g.:
/forms/my-forms/form/123/edit
/forms/my-forms/
I want to take out all numbers from path (if they have no letters before/after the / sings so e.g. 123 but not a123) to $_GET variable and the rest of the path to another $_GET so I will have something like that after rewriting:
index.php?path=forms/my-forms/form/edit&id=123
index.php?path=forms/my-forms/
I've created the .htaccess for this:
Options +FollowSymLinks -MultiViews
RewriteEngine On
RewriteBase /
RewriteCond %{SCRIPT_FILENAME} !-d
RewriteCond %{SCRIPT_FILENAME} !-f
RewriteCond $1 !^(index\.php|robots\.txt)
RewriteRule ^(.*)/([0-9]+)(.*)?$ ./index.php?path=$1$3&id=$2 [L]
RewriteRule ^(.*)$ ./index.php?path=$1 [L]
But it gives me infinitive loop (500 Interla Server Error), despite using [L] for both rules.
When I remove one of the rules, the other works fine (but of course I only have processing of first or second type of urls).
L flag doesn't do what you think it does. L just exists the current Rewrite Cycle and sends the uri for next fase of processing. You are getting rewrite loop error because of your last rule
RewriteRule ^(.*)$ ./index.php?url=$1 [L]
This rewrites everything to /index.php , for your example
in first iteration
http://example.com/foobar gets rewritten to /index.php?url=foobar and then , On the second rewrite iteration /index.php?url=foobar gets rewritten to itself /index.php?url= and thus apache return a 500 Error status to client.
To fix the loop error, you need to tell mod-rewrite to exit the rule processing in first iteration, You can Replace L with END if you are on apache 2.4 , if you are on lower version of apache you can use the following condition above the rule that is causing internal loops
RewriteCond %{ENV_REDIRECT_STATUS} !200
Try with below rule, I didn't tried for now but .* is the one causing problem It matches everything in url and after that most of the rule cease to work other than with .*.
RewriteRule ^(.+?)/([0-9]+)(.+?)?$ ./index.php?path=$1$3&id=$2 [L]
RewriteRule ^(.+?)$ ./index.php?path=$1 [L]
I want to mod_rewrite this Url:
Before:
website.altervista.org/page.php?name=value
After:
website.altervista.org/value
Solution:
RewriteCond %{REQUEST_URI} !page.php$
RewriteRule ^(.+)$ /page.php?name=$1 [L]
Explanation:
The mod_rewrite RewriteRule has 3 parameters:
Pattern
Substitution
Flags
Implemented as such:
RewriteRule pattern substitution [flags]
Starting at server root, enter the requested URL path in the RewriteRule "pattern" parameter, and the desired path in the "substitution" parameter. In this case:
RewriteRule ^(.+)$ /page.php?name=$1 [L]
If the URL varies and you don't want to (or can't) write a rule for every situation then use the regular expression ^(.+)$ to capture the dynamic value and inject it into your substituted path using the RE capture variable $1. The first set of parenthesis is $1, the second set is $2, etc. And capturing parenthesis can be nested.
^(.+)$ This regular expression can be read as: ^ at the start of the string, $ all the way to the end of the string, look for . any character + one or times and () capture that value into a variable.
Problem:
Even though we have the flag [L] (last rule evaluated), the mod_rewrite engine (behind the scenes) sends the newly constructed request /page.php?name=somevalue back through the mod_rewrite engine until no rules are met or, apparently, there are no changes to the request. Fortunately there is a supplimentary directive to expand on the conditional power provided by the RewriteRule called RewriteCond.
The mod_rewrite RewriteCond applies to the next occurring RewriteRule and also has 3 parameters:
Test String
Conditional Pattern
Flags (optional)
The Test String can be derived from a few sources. Often a Server Variable, relating to the current request, is used here as the subject of this condition.
The Conditional Pattern is, again, text or a regular expression, but has some additional special conditions that may be evaluated. Read the Apache online mod_rewrite documentation for a detailed explanation.
In this case: RewriteRule ^(.+)$ /page.php?name=$1 [L], our newly substituted request is sent back through mod_rewrite as /page.php?name=somevalue and matches our "catch-all" rule, therefore our original "somevalue" is lost and replaced with our newly requested resource page.php. To prevent our "catch all" from catching our "page.php" requests let's exclude it from the rule using RewriteCond.
RewriteCond %{REQUEST_URI} !page.php$
RewriteRule ^(.+)$ /page.php?name=$1 [L]
This RewriteCond can be read as: %{REQUEST_URI} get the requested resource and does it ! NOT $ end with page.php. If this condition is true, continue to the next condition or rule. If this condition is not true, skip this rule set and continue to the next rule set.
I'm currently using the following to rewrite http://www.site.com/index.php/test/ to also work directly with http://www.site.com/test/, but I would like to not only allow the second version, I would like to FORCE the second version. If a user goes to http://www.site.com/index.php/test/ it should immediately reroute them to http://www.site.com/test/. index.php should never appear in a url. Stipulation: this should only apply to the first index.php. If I have a title like http://www.site.com/index.php/2011/06/08/remove-index.php-from-urls/ it should leave the second index.php, as it is part of the URL.
Current rule that allows but does not force:
#Remove index.php
RewriteCond $1 !^(index.php|images|css|js|robots.txt)
RewriteRule ^(.*)$ /index.php/$1 [L]
Thanks.
As you wrote, if a user goes to http://www.site.com/index.php/test/ this rule will imediately reroute him to http://www.site.com/test/
RedirectMatch 301 /index.php/(.*)/$ /$1
I'm not sure if that is what you need as your current rewrite rule is opposite to mine.
First (and wrong) answer - see below
You can accomplish a redirection with these directives (in this order):
RewriteCond %{REQUEST_URI} ^index.php
RewriteRule ^index\.php/(.+)$ /$1 [R,L]
RewriteCond $1 !^(index.php|images|css|js|robots.txt)
RewriteRule ^(.*?)$ /index.php/$1 [L]
That will first redirect all the requests that begin with index.php to the corresponding shortened url, then silently serve index.php/etc with the second rule.
EDIT - Please read on!
In fact, the solution above generates an infinite redirection loop, because Apache takes the following actions (let's say we request /index.php/abc):
first RewriteCond matches
Apache redirects [R], that is, generates a new HTTP request, to /abc
/abc fails first RewriteCond
/abc matches second RewriteCond
Apache does not redirect, but rewrites this URI (so it makes an "hidden" request), to /index.php/abc . We are again at point 1, that's a loop.
Please note...
By using the [L] (last rule) flag, we can only tell Apache not to process more rewrite rules, but only if the current rule matches. Since a new HTTP request is made, there is no information about how may redirection we have been through yet. So, any time one of the two matches, and in any case it generates a new request (=>loop)
Using the [C] (chain rules) flag is kinda pointless because it makes Apache process a rule only if the previous rule matches, while the two rules we have are mutually excluding.
Using the [NS] (not if subrequest) flag on rule #1 is again not an option because it aìsimply does not apply to our case (see Apache RewriteRule docs about it)
Setting env variables is not an option (alas), since a new request is made at pt 2, thus destroying all environment variables we set.
An alternative solution can be to rewrite e.g. /abc , to /index.php?path=abc. That is done by these rules (please, delete your RedirectMatch similar rule before adding these):
RedirectMatch ^/index\.php(/.*) $1
RewriteCond %{REQUEST_URI} !^/(index.php|images|css|js|robots.txt|favicon.ico)
RewriteRule ^(.+) /index.php?path=$1 [L,QSA]
I don't know the internals of CodeIgniter's scripts, but as most of the MVC scripts, it will read $_REQUEST['PATH_INFO'] to understand which page is requested. You could slightly modify the code that recognizes the page like this (I assumed that the page path is stored in the $page var):
$page = $_REQUEST['PATH_INFO'];
if(isset($_GET['path']) && strlen($_GET['path'])) $page = $_GET['path']; // Add this line
This won't break the previous code and accomplish what you asked for.