Nintex Forms

Deploying Nintex Forms with PowerShell

When working on a sizeable project with Microsoft SharePoint, Nintex Workflow, and Nintex Forms, it makes sense to automate deployment as much as possible. While it’s straightforward to automate the provisioning of SharePoint assets such as lists, content types, fields, and views through PowerShell, and it’s fairly easy to call NWAdmin to deploy workflows, Nintex Forms have always been something of a problem – until Nintex released a Forms Webservice that is.

It’s still not easy to deploy Nintex Forms via PowerShell, as evidenced by the numerous discussions on both the Nintex community forms, and elsewhere on the internet – with people trying to stick bits of the solution together, and nobody really having the “whole story”. Well this post describes the whole story. I debated for some time about writing this up, because the amount of effort to do it was significant – it gets into that grey area of “this has commercial value”. In the end I decided to share it because I have taken so much from the community over the years, so it might be time to pay something back.

The following PowerShell snippet essentially loops through an arraylist describing the titles of lists, and associated form XML files, and communicates with the Nintex Forms webservice to upload the XML, and publish the forms. It sounds straightforward – it’s anything but. In reality, the script does the following:

  • Calls SharePoint to get a Form Digest
  • Extracts the Form Digest from the response
  • Prepares a POST Web Request to the Nintex Forms Webservice
  • Reads the Form XML file into a byte array
  • Sends the request to the Forms Webservice, streaming the byte array
  • Captures the response from the Forms Webservice

Here’s the guts of it…

$web = Get-SPWeb "https://server/sites/site_collection/subsite"

[System.Reflection.Assembly]::LoadWithPartialName("System.IO") >> $null
[System.Reflection.Assembly]::LoadWithPartialName("Nintex.Forms.SharePoint") >> $null
[System.Reflection.Assembly]::LoadWithPartialName("Nintex.Forms") >> $null

# Build an arraylist of List names, and form xml filenames
$items = New-Object System.Collections.ArrayList
$items.Add(("List A","form_a.xml")) > $null
$items.Add(("List B","form_b.xml")) > $null
$items.Add(("List C","form_c.xml")) > $null

# Check we can see the folder where the form files are
$forms_path = Resolve-Path $(".\Forms\")
if (Test-Path($forms_path)) {

    # loop through the form files
    foreach ($item in $items) {
        
        $list_name = $item[0]
        $form_filename = $item[1]
        
        $form_path = "$forms_path$form_filename"

        Write-Host $(" - Deploying [" + $form_filename + "] to [" + $list_name + "]") -foregroundcolor white
    
        if (Test-Path($form_path)) {

            Write-Host $(" - Form XML File Found")
            
            if ($web.Lists[$list_name]){
                
                # Get Form Digest
                Write-Host " - Getting Form Digest" -NoNewLine
                
                    # Call SharePoint for the Form Digest
                    $form_digest_request = [Microsoft.SharePoint.Utilities.SPUtility]::ConcatUrls($web.Site.RootWeb.Url, "_api/contextinfo")
                    $form_digest_uri = New-Object System.Uri($form_digest_request)
                    $credential_cache = New-Object System.Net.CredentialCache
                    $credential_cache.Add($form_digest_uri, "NTLM", [System.Net.CredentialCache]::DefaultNetworkCredentials)
                    $http_request = [System.Net.HttpWebRequest] [System.Net.HttpWebRequest]::Create($form_digest_request)
                    $http_request.Credentials = $credential_cache
                    $http_request.Method = "POST"
                    $http_request.Accept = "application/json;odata=verbose"
                    $http_request.ContentLength = 0
                    [System.Net.HttpWebResponse] $http_response = [System.Net.HttpWebResponse] $http_request.GetResponse()
                    [System.IO.Stream]$response_stream = $http_response.GetResponseStream()
                    [System.IO.StreamReader] $stream_reader = New-Object System.IO.StreamReader($response_stream)
                    $results = $stream_reader.ReadToEnd()
                    $stream_reader.Close()
                    $response_stream.Close()

                    # Extract the Form Digest Value from the Response
                    $start_tag = "FormDigestValue"
                    $end_tag = "LibraryVersion"
                    $start_tag_index = $results.IndexOf($start_tag) + 1
                    $end_tag_index = $results.IndexOf($end_tag, $start_tag_index)
                    [string] $form_digest = $null
                    if (($start_tag_index -ge 0) -and ($end_tag_index -gt $start_tag_index))
                    {
                        $form_digest = $results.Substring($start_tag_index + $start_tag.Length + 2, $end_tag_index - $start_tag_index - $start_tag.Length - 5)
                    }
                    
                    Write-Host $(" - Form Digest Retrieved")
                
                # Prepare Web Request
                Write-Host " - Preparing Web Request" -NoNewLine
                    
                    $webservice_url = [Microsoft.SharePoint.Utilities.SPUtility]::ConcatUrls($web.Url, "_vti_bin/NintexFormsServices/NfRestService.svc/PublishForm")
                    $webservice_uri = New-Object System.Uri($webservice_url)

                    # Create the web request
                    [System.Net.HttpWebRequest] $request = [System.Net.WebRequest]::Create($webservice_uri)

                    # Add authentication to request 
                    $request.Credentials = [System.Net.CredentialCache]::DefaultNetworkCredentials

                    # Configure Request
                    $request.Method = "POST";
                    $request.ContentType = "application/json; charset=utf-8";
                    $request.Accept = "application/json, text/javascript, */*; q=0.01"
                    $request.Headers.Add("X-RequestDigest", $form_digest); 
                    $request.Headers.Add("X-Requested-With", "XMLHttpRequest")
                    
                    Write-Host " - Request Prepared"

                # Read XML file into byte array
                Write-Host " - Reading XML File" -NoNewLine
                
                    [system.io.stream] $stream = [system.io.File]::OpenRead($form_path)
                    [byte[]] $file_bytes = New-Object byte[] $stream.length
                    [void] $stream.Read($file_bytes, 0, $stream.Length)
                    $stream.Close()
                    
                    try
                    {
                        $form = [Nintex.Forms.FormsHelper]::XmlToObject([Nintex.Forms.NFUtilities]::ConvertByteArrayToString($file_bytes))
                    } catch [Exception] {
                        $form = [Nintex.Forms.FormsHelper]::XmlToObject([Nintex.Forms.NFUtilities]::ConvertByteArrayToString($file_bytes, [System.Text.Encoding]::UTF8))
                    }

                    $form.LiveSettings.Url = ""
                    $form.LiveSettings.ShortUrl = ""
                    $form.RefreshLayoutDisplayNames()
                    $form.Id = [guid]::NewGuid()

                    $form_json = [Nintex.Forms.FormsHelper]::ObjectToJson($form);
                
                    Write-Host $(" - Json Prepared - [" + $form_json.Length + "] chars")

                # Create the data we want to send
                Write-Host " - Generating Data to Send" -NoNewLine
                
                    $list = $web.Lists[$list_name]
                    $id = "{$($list.ID)}"
                    $data = "{`"contentTypeId`": `"`", `"listId`": `"$id`", `"form`": $form_json }"

                    # Create a byte array of the data we want to send 
                    $utf8 = New-Object System.Text.UTF8Encoding 
                    [byte[]] $byte_array = $utf8.GetBytes($data.ToString())

                    # Set the content length in the request headers 
                    $request.ContentLength = $byte_array.Length;
                    
                    Write-Host $(" - [" + $byte_array.Length + "] bytes prepared")

                # Send the Request
                Write-Host " - Sending the Request" -NoNewLine
                    
                    try {
                        $post_stream = $request.GetRequestStream()
                        $post_stream.Write($byte_array, 0, $byte_array.Length);
                    } catch [Exception]{
                        write-host -f red $_.Exception.ToString() 
                    } finally {
                        if($post_stream) {
                            $post_stream.Dispose()
                        }
                    }
                    
                    Write-Host $(" - Sent [" + $byte_array.Length + "] bytes")

                # Get the Response
                Write-Host " - Processing Response"
                
                    try {
                        [System.Net.HttpWebResponse] $response = [System.Net.HttpWebResponse] $request.GetResponse()

                        # Get the response stream 
                        [System.IO.StreamReader] $reader = New-Object System.IO.StreamReader($response.GetResponseStream())

                        try {
                            $strResult = $reader.ReadToEnd()
                            $jsonResult = ConvertFrom-Json $strResult

                        } catch [Exception] {
                            write-host -f red $_.Exception.ToString() 
                        }
                    } catch [Exception] {
                        write-host -f red $_.Exception.ToString() 
                    } finally {
                        if($response) {
                            $response.Dispose()
                        }
                    }
            
            } else {
            
                # List not found
                Write-Host $(" - List [" + $list_name + "] not found") -foreground-color red
                
            }
            
        } else {
        
            # form_path not found
            Write-Host $(" - Form Path [" + $form_filename + "] not found") -foregroundcolor red
        
        }
        
    } # foreach item in arraylist

} else {

    # forms_path not found
    Write-Host $(" - Forms Path [ " + $forms_path + "] not found") -foregroundcolor red
}

# release resources
$web.Close()
$web.Dispose()

Hopefully this will be useful to somebody, somewhere. I read a lot of documentation to come up with this method, and also looked at pieces of the puzzle that other people had completed before solving it. Of course as with any solution like this, the complexity vanishes at runtime – with forms importing and publishing at a rate of one or two per second into SharePoint – certainly faster than importing and publishing them by hand.

Posted by Jonathan Beckett in Notes, 0 comments

Repairing Nintex Forms in Exported Nintex Workflows

A little while ago I was working on a SharePoint development project with Nintex Workflows and Nintex Forms. The project was being developed remotely – in a virtual machine – and then deployment scripts were given to the client to install on their development, test, and production farms as testing progressed. Along the way we found a pretty serious bug in Nintex Workflow and Forms, but thankfully found a workaround.

The Problem

When you design the forms for tasks within a Nintex Workflow (using Nintex Forms) the form designs are embedded in the Nintex Workflow when you export it. If you export a form directly from the form designer, you end up with an XML file describing the form. If you export a workflow containing a task form design from the workflow designer, you end up with an XML file describing the workflow, with the XML describing the task form escaped within it. The problem comes when you export from one farm, and import into another – you will discover the task forms may fail in the destination system. After a bit of digging, I figured out the the XML describing the forms contains hard-coded server relative paths to the origin system in Lookup fields, that are not dealt with during the import – or at least, that’s how I have seen this problem occur – there may be other field types that also have the source system URL baked into them.

It’s worth noting that I have contacted Nintex Support about this issue – I will update when they get back to me.

The Solution

The solution is pretty straightforward really – you can run some PowerShell to read the exported Workflows, replace the relative paths, and write them back. In the example below, we presume that all of the exported workflows exist within a folder called “Workflows”, and the modified versions will be stored in a subfolder called “Modified”.

# Connect to SharePoint
$web = Get-SPWeb "https://server/sites/site_collection/subsite"

$uri = [System.Uri]$url

# server relative path of site the workflows originally existed at
$source_localpath = "/sites/site_collection/subsite"

# server relative path of the site where the workflows are going to be imported
$destination_localpath = $uri.LocalPath

# escape the paths (because we will find both unescaped and escaped versions of the paths)
$source_localpath_escaped = $source_localpath -replace "/","\\/"
$destination_localpath_escaped = $destination_localpath -replace "/","`\/"

# Loop through files in Workflows subdirectory
foreach ( $source_file in $(Get-ChildItem './Workflows' -File | Sort-Object -Property Name) ) {
    
    # read the workflow file
    $file_content = Get-Content "./Workflows/List Workflows/$source_file"
    
    # replace the paths
    write-host " - Replace Paths"
    $file_content = $file_content -replace $source_localpath,$destination_localpath
    $file_content = $file_content -replace $source_localpath_escaped,$destination_localpath_escaped
            
    # Write the file into the modified subdirectory
    $file_content | out-file -encoding utf8 "../Workflows/Modified/$source_file"

}

# release resources
$web.Close()
$web.Dispose()

The script results in a modified set of exported workflows, which will import correctly into the destination farm. It’s worth noting that if you don’t do this, you end up in a world of trouble, because you can’t repair the forms the workflow import breaks – and you don’t know they are broken until you try to use them. I discovered the cause after digging through the SharePoint ULS logs.

I’m amazed that this particular bug got past quality control at Nintex, but then it’s a fantastically complex piece of kit, and so is SharePoint that it sits on top of. It’s also worth noting that this only effects the development of systems using multiple farms for development, testing, and production – if you do agile development in production, you would never see this problem.

Posted by Jonathan Beckett in Notes, 0 comments