Huddled Masses » WatiN

Did you know PowerShell can use Selenium?

Joel 'Jaykul' Bennett — Thu, 05 Jan 2012 05:46:42 +0000

This is sort-of a place-holder for a full-length post that I really ought to write about driving web testing from PowerShell using Selenium. I actually have a little module around for doing that with WaTiN, but honestly the Selenium project seems to be a lot more active, and has quite a bit of muscle behind it since they’ve merged with WebDriver…

Add-Type -path ~\Downloads\selenium-dotnet-2.16.0\net40\WebDriver.dll 

# Navigate to google in IE (or Firefox, Chrome, Opera, etc)

$driver = New-Object OpenQA.Selenium.IE.InternetExplorerDriver 

$driver.Url = "http://google.com"

# Type PowerShell into the query box, the page will update via AJAX

# Note we won't hit enter or anything

$q = $driver.FindElementByname("q") 

$q.SendKeys("PowerShell") 

# Use a CSS selector to find the first result link and click it

$driver.FindElementByCssSelector("li.g h3.r a").Click()

One Catch

If you try this with IE and you get the error Unexpected error launching Internet Explorer. Protected Mode must be set to the same value (enabled or disabled) for all zones ... it means exactly what it says. You need to open “Internet Options” from your start menu (or from IE), and go through each “zone” and set the “Enabled Protected Mode” check box to the same value for each zone (either all checked, obviously the most secure, or all unchecked). I’m not going to debate whether setting them all unprotected is a good idea … I set mine to all protected, but I don’t generally use IE anyway.

If you want more help, Selenium’s documentation is great, and there’s a section on Getting Started with Selenium WebDriver which I found quite helpful (make sure your examples are in “csharp” and you can almost just copy and paste — someone should offer to do them in PowerShell).

If you want more information about the Internet Explorer driver and this problem in particular, the short answer is that “Protected Mode” is a security boundry, so if you cross over it the COM automation object doesn’t work — thus, you need to make sure you always stay on the same side. There’s a good discussion on the mailing list archive about how it works and why, as well a weird alternative documented on the Selenium JavaDocs

Convert Twitter users into FriendFeed Imaginary Friends!

Joel 'Jaykul' Bennett — Sat, 16 May 2009 20:15:47 +0000

So a lot of people seem to be taking the latest missteps by Twitter’s management (and the accompanying admission of bad design) as an opportunity to try out some alternatives. Many of them seem to be coming over to FriendFeed (which has been better than Twitter for a long time, but nevermind that) ... so I thought I’d update and release a PowerShell 2.0 script I wrote to create imaginary friends out of your friends that stay on Twitter.

The first part of it is a WatiN script (that automates your browser) called New-ImaginaryFriend which takes three parameters: a name for the imaginary friend, a url for an avatar for the friend, and a HashTable… Of course, we sort-of cheat by using the HashTable … it’s basically a bunch of key-value pairs of remote services and user names. You can use it to add twitter ID’s like twitter="jsnover" or blogs like blog="http://HuddledMasses.org/" etc. You can even add multiple sources (eg: twitter + diigo, two blogs, etc) to a single new imaginary friend ...

This script is done using WatiN because the FriendFeed API doesn’t support creating imaginary friends yet, and as a result it’s slow, and requires IE (and doesn’t seem to work very well with IE8 — at least, I couldn’t get it to set the avatars using IE 8 on Windows 7, so I commented out the avatar part of the next-to-last line).

The other part of the script is a pair of functions: the first is Get-FriendFeedFriends which retrieves profile information for all your friends in a slick format that includes all their services and such … you may find other uses for this later , the second is Get-TwitterFriends … Both have an -Exclude parameter so you can pass it a list of people to ignore.

When you put these three functions together, you can just import the FriendFeed module, and start creating friends (don’t forget this version of the scripts only works with IE6 or IE7 for the purpose of avatars, as WatiN can’t seem to set the file upload value in IE8 yet).

Import-Module FriendFeed

## Get any twitter friends who aren't on friendfeed

## Make sure you use FriendFeed's built in "add all your twitter friends" first

$twits = Get-TwitterFriends `

         -Nickname jaykul

         -Exclude $(Get-FriendFeedFriends jaykul | select -expand twitter)

## Add them to friend feed

foreach($twit in $twits) {

   New-ImaginaryFriend $twit.name @{twitter=$twit.screen_name} $twit.profile_image_url

}

You can download all of the required modules at once (7z), or grab the latest versions of them from PoshCode: FriendFeed, HttpRest, and WatiN … but if you do that, you’ll still need to get the binaries separately

Using PowerShell and WatiN (PowerWatin?)

Joel 'Jaykul' Bennett — Wed, 11 Mar 2009 06:10:50 +0000

This is an update to a previous article.

Someone asked (on Twitter) about using WatiN from PowerShell, and pointed to this old post by Scott Hanselman saying he was having the same problems … so I wrote this to help them out:

WatiN requires -STA mode

Note: WatiN requires Single Threaded Apartment mode, so you need to be using PowerShell 2.0 (currently in CTP3) in order for any of this to work, and you need to pass the -STA parameter to PowerShell. Regardless, I thought I’d throw two tips out here:

Don’t use `LoadFile`, use `LoadFrom`

I’m not 100% sure when it’s appropriate to use LoadFile in PowerShell, but I can tell you that if your assembly is in a folder with a bunch of other assemblies upon which it depends … you need to use [Reflection.Assembly]::LoadFrom( $path ) instead — because the .net loader will be able to find the dependencies.

Generate some functions to help yourself out

It’s trivial to do code-generation in PowerShell, and WatiN is not friendly to the PowerShell syntax, so you’re going to want to generate a bunch of them. To get you started, here’s a set of Find-* functions to let you find each type of element that WatiN recognizes and automates… by name, id, class, style … well, by any attribute, really:

Function Start-Watin {

## CHANGE this to point to your WatiN.Core.dll

$WatinPath = Convert-Path (Resolve-Path "$(Split-Path $Profile)\Libraries\WatiN.Core.dll")

## Load the assembly

$global:watin = [Reflection.Assembly]::LoadFrom( $WatinPath )

## Create an initial window (I'm creating IE, but WatiN handles Firefox too)

$global:ie = new-object WatiN.Core.IE("http://www.google.com")

## Generate Find-Button, Find-TextField, etc:

$ie | Get-Member -Type Method | 

      Where-Object {

         $type = $_.Definition.Split(" ")[0]

         [WatiN.Core.Element].IsAssignableFrom( ([type]$type) )

      } | ForEach-Object {

         New-Item -Path "Function:Find-$($_.Name)" -Value $( iex @"

{

Param(`$Attribute, [regex]`$value)

`$ie.$($_.Name)( ([Watin.Core.Find]::By( `$Attribute, `$value)) )

}

"@      )

      }

}

With just that little bit of code, I generated all of these functions:

Find-Area
Find-Button
Find-CheckBox
Find-Div
Find-Element
Find-FileUpload
Find-Form
Find-Image
Find-Label
Find-Link
Find-Para
Find-RadioButton
Find-SelectList
Find-Span
Find-Table
Find-TableBody
Find-TableCell
Find-TableRow

Find-TextField

And each function takes the name of an attribute, like say: Alt, Class, For, Id, Index, Name, Src, Style, Text, Title, Url, Value … or just “Element” ... and a regular expression to match against the value of that attribute, and finds the control(s) that match. So for instance … since I’ve got a browser open to Google, I could trigger a search for my name by just doing:

Find-TextField Name q | % { $_.TypeText( "Joel Bennett" ) }

Find-Button Name btnG | % { $_.Click() }

Drat, the lawyer and that pottery guy still beat me out, maybe I should stop using “Jaykul” everywhere and start using my real name more …

Edit: Another example

Someone asked in the comments about how to parse a table, and I thought I’d post an example, because it’s pretty cool how well PowerShell works for stuff like this. Lets say I wanted to scan down a column in a table, and depending on the values, return a value from another column. For an example, I’ll take a table off Wikipedia which lists multi-protocol IM clients, and try to return the names of the clients which support IRC.

## Using the function defined earlier ...

Start-Watin

## Now navigate to the page

$ie.Goto( "http://en.wikipedia.org/wiki/Multiprotocol_instant_messaging_application" )

## Find that first table (yeah, you just have to know the ID):

$table = Find-Table Id sortable_table_id_0

## we COULD do this to figure out which column is the IRC column:

## It's hard because there's no mapping for TH in WatiN

## Personally, I think they should show up in .TableCells

## -1 for the "th" element that's missing from TableRow[1..n].TableCells

$column=-1; 

$table.TableRows[0].Elements | Where-Object {$_.TagName -eq "th"} | 

   ForEach-Object{ if($_.Text -match "IRC"){ break } $column++ }

## Now we loop all rows, and examine that column 

## If we find a "Yes", print out the table header for that row:

$table.TableRows | Where-Object { $_.TableCells[$column] -match "Yes" } | 

   ForEach-Object { $_.Elements } | 

   Where-Object   { $_.TagName -eq "th"} | 

   ForEach-Object { $_.Text }

Clearly WatiN needs to fix the missin <th> TableHeader problem, but other than that, this wasn’t too painful. Of course, it would be a lot easier if we could cast ScriptBlocks as the generic Predicate<T> that the various .Find methods accept, but if I try this, it just freezes up and never returns:

$table.TableRows[0].Element( {$arg[0].TagName -eq "th"} )

Future Work

You could easily take this a lot further: dump those functions into a file for reusing next time (so you don’t have to regenerate them each time), and in fact, it would be relatively simple to make functions for each of the methods on each of the types we found above, so you would have a Click-Button function, and a TypeText-TextField function which could take those same search parameters (attribute and regular expression) and you could even generate appropriate parameters to take, for example, the text to type. In fact, you could generate a whole DSL for yourself … this guy did it using MGrammar … but why not PowerShell.