htaccess maximum number lines for perfomance considerations - .htaccess

As a result of merging several sites together, I have a couple of thousand pages that need to be redirected. I cannot use wildcards as they are specific pages, so they will all be the form of:
Redirect 301 /old_page.html http://www.example.com/new_page.html
Is there a recommendation on how many lines can be in the .htaccess file before it starts to become a performance issue? I'm sure it depends somewhat on the apache configuration, system memory, etc. but I'm trying to get an estimate. Is 2,000 lines too long, or should it be 200, or is 20,000 okay?

I have a couple of thousand pages that need to be redirected. I cannot use wildcards as they are specific pages, so they will all be the form of:
Redirect 301 /old_page.html http://www.site.com/new_page.html
Nope, don't do that.
Redirect everything (expect maybe static ressources like js, css, images, ... that have not changed) for that no current content can be found to a script instead - and have that look up the new URL corresponding to the old one requested, and then does a redirect with a Location header.

Related

How to ignore/redirect all URLs matching a certain string

I am using the Wordpress plugin, Timely All-in-One events calendar. Unfortunately it is creating a plethora of duplicate URLs which end in strings like (https://www.mywebsite.com/events/action~agenda/page_offset~-2/request_format~json/cat_ids~4) or (https://www.mywebsite.com/events/action~oneday/exact_date~2-4-2019/) for example.
As a consequence of these URL directives each being for a different calendar view but containing the same webpage title and content, some search engines are seeing this as duplicate content. Whilst robots.txt is setup to tell bots to ignore the URLs containing said strings, some crawlers are ignoring robots.txt. I have also disabled the various different calendar views so there is now only the agenda view but even in spite of this, bots continue to crawl these URLs.
Therefore is it possible to use Apache/ a .htaccess directive to tell the server to direct any requests containing "/action~" to either remove the string from the URL so the browser just reads "/events/" or to redirect/forward the URLs to another page.
There are over 500 of these URLs so I ideally would like a quick remedy!
Thanks in advance.
Check this rewrite in your .htaccess file
RewriteEngine On
RewriteRule ^events\/action(.*)$ /events/ [L,R=301]

.htaccess files, and how they're meant to look?

I'm currently taking a look at the .htaccess file for my company, in order to add several 301 redirects to it, but it appears as though the file's been corrupted with several dozen injections of malware involving rewrites to other URLs, all starting roughly halfway through the document.
I'd like to return this file to a useable state, but i really do not know if there is such a thing as a vanilla flavoured .htaccess doc that i can safely use, or if i will be compromising the site as it currently exists by simply removing all of the entries in the current file so that it exists as a blank slate?

CakePHP nice urls - how to prevent normal urls from working

I have a website that's written using CakePHP. I've added some rewrite rules in the .htacces file to change the default urls to different ones (instead of /controller1/action1/parameter I have /some-string-about-controller-and-action/parameter, for example).
The problem is that now both the normal url and the nice one are available, and google seems to be indexing both, which is a problem. I'd like to only keep the nice one, which is the proper way to handle this so that it affects the google results as little as possible?
I don't know why you don't want to use cakes own routing (if you are having trouble doing what you want, you can accomplish what you want with a custom route class), then make sure that you redirect all relevant URL's in your .htaccess file to the desired URL using a MOVED PERMANENTLY redirect.
This way google will index the target url instead of the one that is undesirable. You are right to take offense to this, double indexing is a great way to harm your SEO rankings.

Using one directory with different aliases using .htaccess

I'm redeveloping a site (replacing it with one based on CodeIgniter), which is currently a horrid mess of repeated procedural code, however, it has good search engine rankings. Because of this, I need to keep the exact same URL structure.
The company has many different quote pages, which are all essentially the same - so I've produced one clean version which can be used everywhere.
The quote system is now in a folder called /get-quote, but due to the old URLs being required, that folder mustn't be visible anywhere.
I'd like the following to happen, but don't know how to:
A user accessing /insurancequote.php should (on the server) load the /get-quote/ directory (which in turn will load the default CI route). The Base URL in CI should be http://www.mysite.com/insurancequote.php (I'm able to do that bit), so moving to step 2 would result in: http://www.mysite.com/insurancequote.php/step2 (which would map to /get-quote/step2).
Secondly, a user accessing /brokerquote.php should show mysite.com/broker in the address bar (redirect?), but on the server access /get-quote/broker.
Thirdly, a user accessing one of many broker-specific pages, e.g. mysite.com/brokername1.php or mysite.com/broker/brokername2.php (yep, they are scattered all over the place! - but I do know where each one is) should show mysite.com/broker/brokername1 or mysite.com/broker/brokername2. On the server, /get-quote/broker/brokername1 or /get-quote/broker/brokername2 should be accessed.
I don't think what I've written is completely clear, so maybe sudocode helps:
If '/insurancequote.php'
Dont Redirect
Use '/get-quote/'
If '/brokerquote.php'
Redirect '/broker/'
Use '/get-quote/broker/'
// Do the following (manually) for each broker
If '/brokername1.php'
Redirect '/broker/brokername1/'
Use '/get-quote/broker/brokername1/'
If '/brokers/bname2.php'
Redirect '/broker/brokername2/'
Use '/get-quote/broker/brokername2/'
If '/mybrokerpage.php'
Redirect '/broker/mybroker/'
Use '/get-quote/broker/mybroker/'
Is this possible? If so, how would I go about doing it?
Thanks!
The risk you take is messing up your new clean code for historical reasons (and the guy coming next you will say, WTF, this is a mess!).
For me the right solution would be handling the url migration in apache and not in your application. Every refferenced url that you do not want to keep should get a 410 - Gone message (think about referenced images for example) and every referenced page which have a new matching page should get a 301 - moved permanently redirection on the right page. Then after some time as gone check the access log of your server, and if nobody checks the old url anymore then remove the rules.
If you know every old url and every matching url then use a matching url file (or hash file, faster) and manage the redirection 301 with rewriteMap. You can have a really big number of files in a hash file, the match should be fast. And it should be a temporary function, waiting for robots to fix the urls.

Having huge redirect list in .htaccess a Problem?

I want to redirect every post 301 redirect, but I have over 3000 posts.
If I list
Redirect permanent /blog/2010/07/post.html http://new.blog.com/2010/07/23/post/
Redirect permanent /blog/2010/07/post1.html http://new.blog.com/2010/07/24/post1/
Redirect permanent /blog/2010/07/post2.html http://new.blog.com/2010/07/25/post2/
Redirect permanent /blog/2010/07/post3.html http://new.blog.com/2010/07/26/post3/
Redirect per......
for over 3000 url redirect command in .htaccess would this eat my server resource or cause some problem? Im not sure how .htaccess work but if the server is looking at these lists each time user requests for page, I would guess it will be a resource hog.
I can't use RedirectMatch because I added date variable in my new url. Do you have any other suggestions redirecting these posts? Or am I just fine?
Thanks!
I am not an Apache expert, so I cannot speak to whether or not having 3,000 redirects in .htaccess is a problem (though my gut tells me it probably is a bad idea). However, as a simpler solution to your problem, why not use mod_rewrite to do your redirects?
RewriteRule ^/blog/(.+)/(.+)/(.+).html$ http://new.blog.com/$1/$2/$3/ [R=permanent]
This uses a regex to match old URLs and rewrite them to new ones. The [R=permanent] instructs mod_rewrite to issue a 301 with the new URL instead of silently rewriting the request internally.
In your example, it looks like you've added the day of the post to the URL, which does not exist in the old URL. Since you obviously cannot use a regexp to divine the day an arbitrary post was made, this method may not work for you. If you can drop the day from the URL, then you're good to go.
Edit: The first time I read your question, I missed the last paragraph. ("I can't use RedirectMatch because I added date variable in my new url.") In this case, you can use mod_rewrite's RewriteMap to lookup the day component of a post.
You have two options:
Use a hashmap to perform fast lookups in a static file. This means all your old URLs will work, but any new posts cannot be accessed using the old URL scheme.
Use a script to grab the day.
In option one, create a file called posts.txt and put:
/yyyy/mm/pppp dd
...for each post where yyyy is the year of the post, mm is the month, and pppp is the post name (without the .html).
When you're done, run:
$ httxt2dbm -i posts.txt -o posts.map
Then we add to to the server/virtual server config: (Note the path is a filesystem path, not a URL.)
RewriteMap postday dbm:/path/to/file/posts.map
RewriteRule ^/blog/(.+)/(.+)/(.+).html$ http://new.blog.com/$1/$2/${postday:$1/$2/$3}/$3/ [R=permanent]
In option two, use pgm:/path/to/script/lookup.whatever as your RewriteMap. See the mod_rewrite documentation for more info about using a script.
Doing the lookup in mod_rewrite is better than just redirecting to a script which looks up the date and then redirects to the final destination because you should never redirect more than once. Issuing a 301 or 302 incurs a round trip cost, which increases the latency of your page load time.
If you have some way in code to determine the day of a post, you can generate the rewrite on the fly. You can setup a mod_rewrite pattern, something like .html and set up a front controller pattern to calculate the new url from the old and issue the 301 header.
With php as an example:
$_SERVER['REQUEST_URI']
will contain the requested url and
header("Location: http://new.blog.com/$y/$m/$d/$title/",TRUE,301);
will send a redirect.
That's... a lot of redirects. But the first thing I would tell you, and probably the only thing I can tell you without qualification, is that you should run some tests and see what the access times for your blog are like, and also look at the server's CPU and memory usage while you're doing it. If they're fairly low even with that giant list of redirects, you're okay as long as your blog doesn't experience a sudden increase in traffic. (I strongly suspect the 3000 rewrites will be slowing Apache down a lot, though)
That being said, I would second josh's suggestion of replacing the redirects with something dynamic. Like animuson said, if you're willing to drop the day from the URL, it'll be easy to set up a RewriteRule directive to handle the redirection. Otherwise, you could do it with a PHP script, or generally some code in whatever scripting language you (can) use. If you're using one of the popular blog engines, it probably contains code to do this already. Basically you could do something like
RewriteRule .* /blog/index.php
and just let the PHP script sort out which post was requested. It has access to the database so it'll be able to do that, and then you can either display the post directly from the PHP script, or to recover your original redirection behavior, you can send a Location header with the correct URL.
An alternative would be to use RewriteMap, which lets you write a RewriteRule where the target is determined by a program or file of your choice instead of being directly specified in the configuration file. As one option, you can specify a text file that contains the old and new URLs, and Apache will handle searching the file for the appropriate line for any given request. Read the documentation (linked above) for the full details. I will mention that this isn't used very often, and I'm not sure how much faster it would be compared to just having 3000 redirects.
Last tip: Apache can be significantly faster if you're able to move the configuration directives (like Redirect) into the server or virtual host configuration file, and disable reading of .htaccess entirely. I would guess that moving 3000 directives from .htaccess into the virtual host configuration could make your server considerably faster. But even moving the directives into the vhost config file probably wouldn't produce as much of a speedup as using a single RewriteRule.
It's never a good idea to make a massive list of Redirects. A better programming technique is to simply redirect the pages without that date variable then have a small PHP snippet that detects if it's missing and redirects to the URL with it included. The long list looks tacky and slows down Apache because it's checking that URL (any every other URL that might not even be affected by this) against each line. If it were only 5 or so, I'd say fine, but 3,000 is a definite NO.
Although I'm not a big fan of this method, a better choice would be to redirect all those URLs normally using a single match statement, redirecting them to the page without the date part, or with a dash or something, then include a small PHP snippet to check if the date is valid and if not, rewrite the path again to the correctly formed URL.
Honestly, if you didn't have that part there before, you don't need it now, and it will probably just confuse the search engines changing the URL for 3,000 posts. You don't really need a date in the URL, a good title is much more meaningful not only to users, but also to search engines, than a bunch of numbers.

Resources