Warning: SiteDiff 1.2.0 requires at least Ruby 3.1.2.
Warning: SiteDiff 1.0.0 introduces some backwards incompatible changes.
- Introduction
- Installation
- Demo
- Usage
- Command Line Options
- Configuration
- Tips and Tricks
- Acknowledgements
SiteDiff makes it easy to see how a website changes. It can compare two similar sites or it can show how a single site changed over time. It helps identify undesirable changes to the site's HTML and it's a useful tool for conducting QA on re-deployments, site upgrades, and more!
When you run SiteDiff, it produces an HTML report showing whether pages on your site have changed or not. For pages that have changed, you can see a colorized diff exactly what changed, or compare the visual differences side-by-side in a browser.
SiteDiff supports a range of normalization / sanitization rules. These allow you to eliminate spurious differences, narrowing down differences to the ones that materially affect the site.
SiteDiff is fairly easy to install. Please refer to the installation docs.
After installing all dependencies including the bundle
version 2 gem, you can quickly
see what SiteDiff can do. Simply use the following commands:
git clone https://github.com/evolvingweb/sitediff
cd sitediff
bundle install
bundle exec thor fixture:serve
Then visit https://localhost:13080/
to view the report.
SiteDiff shows you an overview of all the pages and clearly indicates which
pages have changed and not changed.
When you click on a changed page, you see a colorized diff of the page's markup
showing exactly what changed on the page.
Here are some instructions on getting started with SiteDiff. To see a list of commands that SiteDiff offers, you can run:
sitediff help
To get help for a particular command, say, diff
, you can run:
sitediff help diff
To use SiteDiff on your site, create a configuration for your site:
sitediff init https://mysite.example.com
SiteDiff will generate a configuration file named sitediff.yaml
by default.
You can open the configuration file sitediff/sitediff.yaml
to see the
default configuration generated by SiteDiff.
The the configuration reference section explains the contents
of this file and helps you customize it as per your requirements.
Then get SiteDiff to crawl your site by using:
sitediff crawl
SiteDiff will then crawl your site, finding pages and caching their
contents. A list of discovered paths will be saved to a paths.txt
file.
Now, you can make alterations to your site. For example, change a word on your site's front page. After you're done, you can check what actually changed:
sitediff diff
For each page, SiteDiff will report whether it did or did not change. For pages that changed, it will display a diff. You can also see an HTML version of the report using the following command:
sitediff serve
SiteDiff will start an internal web server and open a report page on your browser. For each page, you can see the diff and a side-by-side view of the old and new versions.
You can now see if the changes were as you expected, or if some things didn't quite work out as you hoped. If you noticed unexpected changes, congratulations: SiteDiff just helped you find an issue you would have otherwise missed!
As you fix any issues, you can continue to alter your site and run
sitediff diff
to check the changes against the old version. Once you're
satisfied with the state of your site, you can inform SiteDiff that it should
re-cache your site:
sitediff store
This takes a snapshot of your website and the next time you run
sitediff diff
, it will use this new version as the reference for
comparison.
Happy diffing!
Sometimes you have two sites that you want to compare, for example a production site hosted on a public server and a development site hosted on your computer. SiteDiff can handle this situation, too! Just inform SiteDiff that there are two sites to compare:
sitediff init https://mysite.example.com https://localhost/mysite
Then when you run sitediff diff
, it will compare the cached version of the
first site with the current version of the second site.
If both the first and second sites may be changing, you should tell SiteDiff not to cache either site:
sitediff diff --cached=none
Sometimes sites have spurious differences, that you don't want to show up in a comparison. For example, many sites protect against Cross-Site Request Forgery using a semi-random token. Since this token changes on each HTTP GET, you probably don't care about such a change.
To help with issues such as this, SiteDiff allows you to normalize the HTML it
fetches as it compares pages. In the sitediff.yaml
configuration file,
you can add "sanitization rules", which specify either DOM transformations or
regular expression substitutions.
Here's an example of a rule you might add to remove CSRF-protection tokens generated by Django:
dom_transform:
- title: Remove CSRF tokens
type: remove
selector: input[name=csrfmiddlewaretoken]
You can use one of the presets to apply framework-specific sanitization. Currently, SiteDiff only comes with Drupal-specific presets.
See the preset section for more details.
By default SiteDiff will put everything in the sitediff
folder. You can use
the --directory
flag to specify a different directory.
sitediff init -C my_project_folder https://example.com
sitediff diff -C my_project_folder
sitediff serve -C my_project_folder
When you run sitediff diff
, you can specify which pages to look at in
2 ways:
-
The option
--paths /foo /bar ...
.If you're trying to fix one page in particular, specifying just that one path will make
sitediff diff
run quickly! -
The option
--paths-file FILE
with a newline-delimited text file.
This is particularly useful when you're trying to eliminate all diffs.
SiteDiff creates a file output/failures.txt
containing all paths
which had differences, so as you try to fix differences, you can run:
sitediff diff --paths-file sitediff/failures.txt
When a sanitization rule isn't working quite right for you, you might run
sitediff diff
many times over. If fetching all the pages is taking too long,
try adding the option --cached=all
. This tells SiteDiff not to re-fetch
the content, but just compare previously cached versions — it's a lot faster!
By default sitediff crawls pages that are indicated with an HTML anchor using
the <A HREF
syntax. Most pages linked will be HTML pages, but some links
will contain binaries such as PDF documents and images.
Using the option --exclude='.*\.pdf'
ensures the crawler skips links
for document with a .pdf
extension. Note that the regular expression is
applied to the path of the URL, not the base of the URL.
For example --include='.*\.com'
will not match https://www.google.com/
,
because the path of that URL is /
while the base is www.google.com
.
SiteDiff allows you to specify a list of paths that you want it to work with. Alternatively, it can crawl the entire site and detect all paths.
-
Running
sitediff init
configures SiteDiff for crawling and seeing differences. -
Running
sitediff crawl
makes sitediff crawl your site and detect available paths. These paths are written to apaths.txt
file which you can modify according to your needs. -
You can also compute diffs only for paths specified in a custom paths file using the
--paths-file
parameter. This file should contain paths starting with a/
, having one path per line.sitediff diff --paths-file=/path/to/paths.txt
-
You can also compute diffs for a handful of specific paths by specifying them directly on the command line using the
--paths
parameter. Each path should be separated by a space.sitediff diff --paths=/home /about /contact
Generate a gzipped tar file containing the HTML report instead of generating
and serving live web pages, this option overrides --report-format
, forcing
HTML.
sitediff diff --export
sitediff diff -e
This will perform the diff and export the results in a gzipped tar file.
If you run SiteDiff inside a container or virtual machine, the URLs in its
report might not work from your host, such as localhost
. You can fix
this by using the --before-url-report
and --after-url-report
options, to tell SiteDiff to use a different URL in the report than the one
it uses for fetching.
For example, if you ran sitediff init https://mysite.com https://localhost
inside a Vagrant VM, you might then run
something like:
sitediff diff --after-url-report=https://vagrant:8080
SiteDiff relies on a YAML configuration file, usually
called sitediff.yaml
. You can create a reasonable one using sitediff init
,
but there are many useful things you may want to add or change manually.
In the sitediff.yaml
, SiteDiff recognizes the keys described below. The
config
directory contains some example sitediff.yaml
files. For example,
sitediff.example.yaml.
before_url: https://example.com/subsite
after_url: https://localhost:8080/subsite
They can also be paths to directories on the local filesystem.
The after_url
MUST provided either at the command-line or in the
sitediff.yaml
. If the before_url
is provided, SiteDiff will compare the
two sites. Otherwise, it will compare the current version of the after
site
with the stored version of that site, as created by sitediff init
or
sitediff store
.
Chooses the sections of HTML we wish to compare, if you don't want to compare the entire page. For example if you only want to compare breadcrumbs between your two sites, you might specify:
selector: '#breadcrumb'
A list of regular expression rules to normalize your HTML for comparison.
Each rule should have a pattern regex, which is used to search the HTML. Each found instance is replaced with the provided substitute or deleted if no substitute is provided. A rule may also have a selector, which constrains it to operate only on HTML fragments which match that CSS selector.
For example, forms on Drupal sites have a randomly generated form_build_id
on form pages:
<input type="hidden" name="form_build_id" value="form-1cac6b5b6141a72b2382928249605fb1"/>
We're not interested in comparing random content, so we could use the following rule to fix this:
sanitization:
# Remove form build IDs
- pattern: '<input type="hidden" name="form_build_id" value="form-[a-zA-Z0-9_-]+" *\/?>'
selector: 'input'
substitute: '<input type="hidden" name="form_build_id" value="__form_build_id__">'
Sanitization rules may also have a path attribute, whose value is a regular expression. If present, the rule will only apply to matching paths.
Ignore whitespace when doing the diff. This passes the -w
option to the native OS diff
command.
ignore_whitespace: true
On the command line, use -w
or --ignore-whitespace
.
sitediff diff -w
Applies rules to just one side of the comparison.
These blocks can contain any of the following sections: selector
,
sanitization
, dom_transform
. Such a section placed in before
will be
applied just to the before
side of the comparison and similarly for after
.
For example, if you wanted to let different date formatting not create diff failures, you might use the following:
before:
sanitization:
- pattern: '[1-2][0-9]{3}/[0-1][0-9]/[0-9]{2}'
substitute: '__date__'
after:
sanitization:
- pattern: '[A-Z][a-z]{2} [0-9]{1,2}(st|nd|rd|th) [1-2][0-9]{3}'
substitute: '__date__'
The above rule will replace dates of the form 2004/12/05
in before
and
dates of the form May 12th 2004
in after
with __date__
.
The names of other configuration YAML files to merge with this one.
includes:
- config/sanitize_domains.yaml
- config/strip_css_js.yaml
A list of transformations to apply to the HTML before comparing.
This is similar to sanitization, but it applies transformations to the structure of the HTML, instead of to the text. Each transformation has a type, and potentially other attributes. The following types are available:
Given a selector, removes all elements that match it.
For example, say we have a block containing the current time, which is expected to change. To ignore that, we might choose to delete the block before comparison:
dom_transform:
# Remove current time block
- type: remove
selector: div#block-time
Strip leading and trailing whitespace from the contents of a tag.
Uses the Ruby string strip()
method. Whitespace is defined as any of the
following characters: null, horizontal tab, line feed, vertical tab, form
feed, carriage return, space.
To transform <h1> Foo and Bar\n </h1>
to <h1>Foo and Bar<\h1>
:
dom_transform:
# Strip H1 tags
- type: strip
selector: h1
Given a selector, replaces all matching elements with their children. For example, your content on one side of the comparison might look like this:
<p>This is some text</p>
<img src="lola.png" alt="Lola is a cute kitten." />
But on the other side, it might be wrapped in an article
tag:
<article>
<p>This is some text</p>
<img src="test.png"/>
</article>
You could fix it with the following configuration:
dom_transform:
- type: unwrap
selector: article
Given a selector and a class, removes that class from each element that matches the selector. It can also take a list of classes, instead of just one.
For example, here are two sample rules for removing a single class and
removing multiple classes from all div
elements:
dom_transform:
# Remove class foo from div elements
- type: remove_class
selector: div
class: class-foo
# Remove class bar and class baz from div elements
- type: remove_class
selector: div
class:
- class-bar
- class-baz
Replaces the entire root element with its children.
The settings under the report
key allow you to display helpful details on the report.
report:
title: "Updates to example.com"
details: "This report verifies updates to example.com."
before_note: "The old site"
after_note: "The new site"
before_url_report: https://example.com
after_url_report: https://staging.example.com
Display a title string at the top of the report.
Text displays as a paragraph at the top of the report, below the title.
Display a brief explanatory note next to before
URL.
Display a brief explanatory note next to after
URL.
Changes how SiteDiff reports which URLs it is comparing, but don't change what it actually compares.
Suppose you are serving your 'after' website on a virtual machine with IP 192.168.2.3, and you are also running SiteDiff inside that VM. To make links in the report accessible from outside the VM, you might provide:
after_url: https://localhost
report:
after_url_report: https://192.168.2.3
If you don't wish to have the "Before" or "After" links in the report, set to false:
report:
after_url_report: false
Presets are stored in the /lib/sitediff/presets
directory of this gem. You
can select a preset as follows:
settings:
preset: drupal
A RegEx indicating the paths that should not be crawled.
A RegEx indicating the paths that should be crawled.
If your configuration file starts getting really big, SiteDiff lets you separate it out into multiple files. Just have one base file that includes other files:
includes:
- sanitization.yaml
- paths.yaml
This allows you to separate your configuration into logical groups.
For example, generic rules for your site could live in a generic.yaml
file,
while rules pertaining to a particular update you're conducting could
live in update-8.2.yaml
.
In major upgrades and migrations where there are significant changes to the markup,
simple diffs will not be of much value. To assist in these cases, named regions
let you define regions in the page markup and the specify order in which
they should be compared. Specifying the order helps in cases where the fields are
not in the same order on the new site.
For example, if you have a CMS displaying title
, author
, and body
fields, you
could define the named regions and the selectors for the three fields as follows:
regions:
- name: title
selector: h1.title
- name: author
selector: .field-name-attribution
- name: body
selector: .field-name-body
(You need to define regions
for both the before
and after
sections.)
You must then define the order that the fields should be compared, using the
output
key.
output:
- title
- author
- body
Before the two versions are compared, SiteDiff generates markup with
<region>
tags and each region
contains the markup matching the
corresponding selector.
EG:
<region id="title">
<h1 class="title">My Blog Post</h1>
</region>
<region id="author">
<div class="field-name-attribution">
<span class="label">By:</span> Alfred E. Neuman
</div>
</region>
<region id="body">
<div class="field-name-attribution">
<p>Lorem ipsum...
</div>
</region>
The regions are processed first, so you can reference the <region>
tags to
be more specific in your selectors for dom_transform
and sanitization
sections.
EG:
dom_transform:
- name: Remove body div wrapper
type: unwrap
selector: region#body .field-name-attribution
Many options can be
passed to the underlying curl library. Add --curl_options=name1:value1 name2:value2
to the command line (such as --curl_options=max_recv_speed_large:100000
(remove the CURLOPT_
prefix and write the name in lowercase) or add them to
your configuration file.
settings:
curl_opts:
max_recv_speed_large: 10000
ssl_verifypeer: false
These CURL options can be put under the settings
section of sitediff.yaml
as demonstrated above.
A few options are also available to control how aggressively SiteDiff crawls.
-
There's a command line option
--concurrency=N
forsitediff init
which controls the maximum number of simultaneous connections made. Lower N mean less aggressive. The default is 3. You can specify this in thesitediff.yaml
file under thesettings
key. -
The underlying curl library has many options such as
max_recv_speed_large
which can be helpful. -
There is a special command line option
--interval=T
forsitediff init
. This option and allows the fetcher to delay for T milliseconds between fetching pages. You can specify this in thesitediff.yaml
file under thesettings
key.
By default, no timeout is set but one can be added --curl_options=timeout:60
or in your configuration file.
settings:
curl_opts:
timeout: 60 # In seconds; or...
timeout_ms: 60000 # In milliseconds.
Often development or staging sites are protected by HTTP Authentication.
SiteDiff allows you to specify a username and password, by using a URL like
https://user:[email protected]
or by adding a userpwd
setting to your file.
SiteDiff ignores untrusted certificates by default. This is equivalent to the following settings:
settings:
curl_opts:
ssl_verifypeer: false
ssl_verifyhost: 0
userpwd: "username:password"
This contains various parameters which affect the way SiteDiff works. You can
have the following keys under settings
.
An integer indicating the number of milliseconds SiteDiff should wait for between requests.
The maximum number of simultaneous requests that SiteDiff should make.
The depth to which SiteDiff should crawl the website. Defaults to 3, which means, 3 levels deep.
Options to pass to the underlying curl library. Remove the CURLOPT_
prefix in
this full list of options
and write in lowercase. Useful for throttling.
settings:
curl_opts:
connecttimeout: 3
followlocation: true
max_recv_speed_large: 10000
Here are some tips and tricks that we've learned using SiteDiff:
- Use single quotes or double quotes around selectors. Remember that the
#
is a comment in YAML. - Be specific enough with selectors to not affect elements on other pages.
If you have an empty <p/>
tag appearing in the diff, you can write the following in your sanitization lists:
- name: remove_empty_p
pattern: '<p/>'
substitute: ''
There are times when the HTML tags do not have newlines between them on one of the sites you wish to compare. In this case, these sanitzation rules are useful:
- name: remove_space_before
pattern: '\s*(\n)<'
substitute: '\1<'
- name: remove_space_after
pattern: '>(\n)\s*'
substitute: '>\1'
After writing rules, you may end up with empty attributes, like width=""
. Here's a sanitization rule:
- name: remove_empty_class
pattern: ' class=""'
substitute: ''
SiteDiff is brought to you by Evolving Web.