SYNOPSIS
SWAT is Simple Web Application Test ( Tool )
$ swat examples/google/ google.ru
/home/vagrant/.swat/reports/google.ru/00.t ..
# start swat for google.ru/
# try num 2
ok 1 - successfull response from GET google.ru/
# data file: /home/vagrant/.swat/reports/google.ru/content.GET.txt
ok 2 - GET / returns 200 OK
ok 3 - GET / returns Google
1..3
ok
All tests successful.
Files=1, Tests=3, 12 wallclock secs ( 0.00 usr 0.00 sys + 0.02 cusr 0.00 csys = 0.02 CPU)
Result: PASS
WHY
I know there are a lot of tests tool and frameworks, but let me briefly tell why I created swat. As devops I update a dozens of web application weekly, sometimes I just have no time sitting and wait while dev guys or QA team ensure that deploy is fine and nothing breaks on the road. So I need a tool to run smoke tests against web applications. Not tool only, but the way to create such a tests from the scratch in way easy and fast enough.
So this how I came up with the idea of swat.
Key features
SWAT:
- is very pragmatical tool designed for job to be done in a fast and simple way
- has simple and yet flexible DSL with low price mastering ( see my tutorial )
- produces TAP output
- leverages famous perl prove and curl utilities
- has minimal dependency tree and probably will run out of the box on most linux environments, provided that one has perl/bash/find/curl by hand ( which is true for most cases )
Tutorial
Install swat
stable release
sudo cpan install swat
developer release
# developer release might be untested and unstable
sudo cpanm --mirror-only --mirror https://stratopan.com/melezhik/swat-release/master swat
Once swat is installed you have swat command line tool to run swat tests, but before do this you need to create them.
Create tests
mkdir my-app/ # create a project root directory to contain tests
# define http URIs application should response to
mkdir -p my-app/hello # GET /hello
mkdir -p my-app/hello/world # GET /hello/world
# define the content to return by URIs
echo 200 OK >> my-app/hello/get.txt
echo 200 OK >> my-app/hello/world/get.txt
echo 'This is hello' >> my-app/hello/get.txt
echo 'This is hello world' >> my-app/hello/world/get.txt
Run tests
swat ./my-app http://127.0.0.1
DSL
Swat DSL consists of 2 parts. Routes and Swat Data.
Routes
Routes are http resources a tested web application should have.
Swat utilize file system to get know about routes. Let we have a following project layout:
example/my-app/
example/my-app/hello/
example/my-app/hello/get.txt
example/my-app/hello/world/get.txt
When you give swat a run
swat example/my-app 127.0.0.1
It will find all the directories with get.txt or post.txt files inside and "create" routes:
GET hello/
GET hello/world
When you are done with routes you need to set swat data.
Swat data
Swat data is DSL to describe/generate validation checks you apply to content returned from web application.
Swat data is stored in swat data files, named get.txt or post.txt.
The validation process looks like:
- Swat recursively find files named get.txt or post.txt in the project root directory to get swat data.
- Swat parse swat data file and execute entries found. At the end of this process swat creates a final check list with "Check Expressions".
- For every route swat makes http requests to web application and store content into text file
- Every line of text file is validated by every item in a final check list
Objects found in test data file are called swat entries. There are 3 basic type of swat entries:
- Check Expressions
- Comments
- Perl Expressions and Generators
Check Expressions
This is most usable type of entries you may define at swat data file. It's just a string should be returned when swat request a given URI. Here are examples:
200 OK
Hello World
<head><title>Hello World</title></head>
Using regexps
Regexps are check expresions with the usage of instead of plain strings checks.
Everything started with regexp: marker would be treated as perl regular expression.
# this is example of regexp check
regexp: App Version Number: (\d+\.\d+\.\d+)
Comments
Comments entries are lines started with # symbol, swat will ignore comments when parse swat data file. Here are examples.
# this http status is expected
200 OK
Hello World # this string should be in the response
<head><title>Hello World</title></head> # and it should be proper html code
Perl Expressions
Perl expressions are just a pieces of perl code to get evaled by swat when parsing test data files.
Everything started with code: marker would be treated by swat as perl code to execute.
There are a lot of possibilities! Please follow Test::More documentation to get more info about useful function you may call here.
code: skip('next test is skipped',1) # skip next check forever
HELLO WORLD
code: skip('next test is skipped',1) unless $ENV{'debug'} == 1 # confitionally skip this check
HELLO SWAT
Generators
Swat entries generators is the way to create new swat entries on the fly. Technically specaking it's just a perl code which should return an array reference: Generators are very close to perl expressions ( generators code is alos get evaled ) with maijor difference:
Value returned from generator's code should be array reference. The array is passed back to swat parser so it can create new swat entries from it.
Generators entries start with :generator marker. Here is example:
# Place this in swat data file
generator: [ qw{ foo bar baz } ]
This generator will generate 3 swat entries:
foo
bar
baz
As you can guess an array returned by generator should contain perl strings representing swat entries, here is another example: with generator producing still 3 swat entites 'foo', 'bar', 'baz' :
# Place this in swat date file
generator: my %d = { 'foo' => 'foo value', 'bar' => 'bar value' }; [ map { ( "# $_", "$data{$_}" ) } keys %d ]
This generator will generate 3 swat entities:
# foo
foo value
# bar
bar value
There is no limit for you! Use any code you want with only requiment - it should return array reference. What about to validate web application content with sqlite database entries?
# Place this in swat data file
generator: \
use DBI; \
my $dbh = DBI->connect("dbi:SQLite:dbname=t/data/test.db","",""); \
my $sth = $dbh->prepare("SELECT name from users"); \
$sth->execute(); \
my $results = $sth->fetchall_arrayref; \
[ map { $_->[0] } @${results} ]
As an example take a loot at examples/swat-generators-sqlite3 project
Multiline expressions
Sometimes code looks more readable when you split it on separate chunks. When swat parser meets \ symbols it postpone entry execution and
add next line to buffer. This is repeated till no \ found on next. Finally swat execute "accumulated" swat entity.
Here are some exmaples:
# Place this in swat data file
generator: \
my %d = { \
'foo' => 'foo value', \
'bar' => 'bar value', \
'baz' => 'baz value' \
}; \
[ \
map { ( "# $_", "$data{$_}" ) } keys %d \
] \
# Place this in swat data file
generator: [ \
map { \
uc($_) \
} qw( foo bar baz ) \
]
code: \
if $ENV{'debug'} == 1 { # confitionally skip this check \
skip('next test is skipped',1) \
}
HELLO SWAT
Multiline expressions are only allowable for perl expressions and generators
Generators and Perl Expressions Scope
Swat uses perl string eval when process generators and perl expressions code, be aware of this. Follow http://perldoc.perl.org/functions/eval.html to get more on this.
PERL5LIB
Swat adds $project_root_directory/lib to PERL5LIB , so this is convient convenient to place here custom perl modules:
example/my-app/lib/Foo/Bar/Baz.pm
As an example take a loot at examples/swat-generators-with-lib/ project
Post requests
Name swat data file as post.txt to make http POST requests.
echo 200 OK >> my-app/hello/post.txt
echo 200 OK >> my-app/hello/world/post.txt
You may use curl_params setting ( follow "Swat Settings" section for details ) to define post data, there are some examples:
-
-d- Post data sending by html form submit.# Place this in swat.ini file or sets as env variable: curl_params='-d name=daniel -d skill=lousy' -
--data-binary- Post data sending as is.# Place this in swat.ini file or sets as env variable: curl_params=`echo -E "--data-binary '{\"name\":\"alex\",\"last_name\":\"melezhik\"}'"` curl_params="${curl_params} -H 'Content-Type: application/json'"
Swat Settings
Swat comes with settings defined in two contexts:
- Environmental Variables
- swat.ini files
Environmental Variables
Defining a proper environment variables will provide swat settings.
debug- set to1if you want to see some debug information in output, default value is0debug_bytes- number of bytes of http response to be dumped out when debug is on. default value is500ignore_http_err- ignore http errors, if this parameters is off (set to1) returned error http codes will not result in test fails, useful when one need to test something with response differ from 2**,3** http codes. Default value is0try_num- number of http requests attempts before give it up ( useless for resources with slow response ), default value is2curl_params- additional curl parameters being add to http requests, default value is"", follow curl documentation for variety of values for thiscurl_connec_timeout- follow curl documentationcurl_max_time- follow curl documentationport- http port of tested host, default value is80
Swat.ini files
Swat checks files named swat.ini in the following directories
- ~/swat.ini
- $project_root_directory/swat.ini
- $route_directory/swat.ini
Here are examples of locations of swat.ini files:
~/swat.ini # home directory swat.ini file
my-app/swat.ini # project_root directory swat.ini file
my-app/hello/get.txt
my-app/hello/swat.ini # route directory swat.ini file ( route hello )
my-app/hello/world/get.txt
my-app/hello/world/swat.ini # route directory swat.ini file ( route hello/world )
Once file exists at any location swat simply bash sources it to apply settings.
Thus swat.ini file should be bash file with swat variables definitions. Here is example:
# the content of swat.ini file:
curl_params="-H 'Content-Type: text/html'"
debug=1
Settings priority table
Here is the list of settings/contexts in priority ascending order:
| context | location | priority level |
| ------------------------|------------------------ | --------------- |
| swat.ini file | ~/swat.ini | 1 |
| environmental variables | --- | 2 |
| swat.ini file | project root directory | 3 |
| swat.ini file | route directory | 4 |
Swat processes settings in order. For every route found swat:
- Clear all settings
- Apply settings from environmental variables ( if any given )
- Apply settings from swat.ini file in home directory ( if any given )
- Apply settings from swat.ini file in project root directory ( if any given )
- And finally apply settings from swat.ini file in route directory ( if any given )
TAP
Swat produces output in TAP format , that means you may use your favorite tap parsers to bring result to another test / reporting systems, follow TAP documentation to get more on this. Here is example for converting swat tests into JUNIT format
swat $project_root $host --formatter TAP::Formatter::JUnit
See also "Prove settings" section.
Command line tool
Swat is shipped as cpan package, once it's installed ( see "Install swat" section ) you have a command line tool called swat, this is usage info on it:
swat project_root_dir|swat_package URL <prove settings>
- URL - is base url for web application you run tests against, you need defined routes which will be requested against URL, see DSL section.
- project_dir - is a project root directory
- swat_package - the name of swat package, see "Swat Packages" section
Prove settings
Swat utilize prove utility to run tests, so all the swat options are passed as is to prove utility.
Follow prove utility documentation for variety of values you may set here.
Default value for prove options is -v. Here is another examples:
-q -s- run tests in random and quite mode
Swat Packages
Swat packages is distributable archives of swat tests. It's easy to create your own swat packages and share with other.
This is mini how-to on creating swat packages:
Create swat package
Let's imagine you've got ready swat tests you want to distribute. First of all you need to create _tar.gz archive_ of swat project root directory:
tar -zcf $project_root_dir.tar.gz project_root_dir
For example for project ./examples/google
cd ./examples/
tar -zcf google.tar.gz ./google
Upload package to swat repository
Swat repository might be _ANY_ web server. One should upload archive into server. Let's say we have nginx server. The example below is for debian:
# install nginx:
sudo apt-get install nginx
# copy swat distributive:
sudo cp google.tar.gz /var/www/html/
# check for archive availability over web server:
curl -s 127.0.0.1/google.tar.gz -D - -o /dev/null | head -n 1
HTTP/1.1 200 OK
You swat repository with nginx swat package uploaded is ready!
Install swat package
Swat comes with utility called swatman to manage swat packages. First of all one need to setup swat repository:
echo "swat_repo=127.0.0.1" >> ~/swat.ini
Then install package
swatman install google
Run swat tests
Once swat package is installed into your system you may give it a run:
swat google google.ru
Debugging
set swat_debug environmental variable to 1
Examples
./examples directory contains examples of swat tests for different cases. Follow README.md files for details.
Dependencies
Not that many :)
- perl
- curl
- bash
- find
- head
- tar
AUTHOR
Swat Project Home Page
https://github.com/melezhik/swat
Thanks
To the authors of ( see list ) without who swat would not appear to light
- perl
- curl
- TAP
- Test::More
- prove