How Do You Get a Power Page Attachment That’s Stored in Blob Storage

My Power App Portal (Power Pages) environments are configured to use Azure blob storage for form attachments. One of the primary reasons for doing this is to avoid filling up expensive dataverse storage with endless attachments submitted by enduers.

This article outlines how to set up Azure storage: link

What I’m going to demo is how to get ONE attachment that’s uploaded to a form. If your form allows multiple attachments, you’d simply loop through them.

In the example, I’m using the soon-to-be-obsolete dataverse connector, but the same basic flow design applies to the normal connector.

When a row is added to my table, the flow is triggered.
The flow then queries the Note (annotation) table using the ID from the source table.
filter query: (_objetid_value eq souce_table_id)

The list rows notes query will result in an array being returned, but I’m only dealing with one attachment, so there’s no need to loop through it. To avoid an unnecessary loop, a function can be used to target a single object from the array: first(body(‘List_rows_Notes’)?[‘value’])?[‘annotationid’]

From the Get row note action, annotationid and filename will be needed to help form the path to the blob. Using the concat function I’m combing the container name, annotationid, and filename. Also, note the transformation on annotationid, the hyphens need to be removed, and the string needs to be lowercase. The last part of the transformation is to remove .azure.txt from the filename.

concat('/blobcontainer/',toLower(replace(outputs('Get_row_Note')?['body/annotationid'], '-', '')),'/', split(outputs('Get_row_Note')?['body/filename'], '.azure.txt')[0])

The end result of the transformation will be:
/blobcontainer/annotationid/filename /blobcontainer/cf03e4cf7f72ad118561002248881923/example.pdf

With the path to the blob formed, the get blob content action can retrieve the file.

It’s that simple.

A couple of notes:
It would be wise to leverage a virus-scanning tool like Cloudmersive.
If you haven’t already noticed, when a user uploads a file that contains special characters in the name…it’s saved to the Note table without the special characters, but when it’s moved to blob storage, the characters will be in the name. Yes, that’s a bug Microsoft has yet to fix. You can avoid this by adding Javascript to the upload page to block files that fall into this category. OR. Write another flow to clean file names before the form is processed.
Example:
Uploaded filename: my report 1:2:3.pdf
Note table: my report 123.pdf
Blob: my report 1:2:3.pdf

Password Complexity Page using Azure B2C and Power Pages

Currently working on a project, and my UX team asked if it was possible to change the look of the B2C sign-up / password change page to include visual hints to meet the password complexity requirements. We’ve all seen it before, you visit a site where you need to sign up, and the password needs to be X characters long and contain this and that, but some sites include a cute visual to help identify what requirements have been met.

image borrowed from jQuery Script


Articles and blog posts I used to get this working:
1. Customize the Azure AD B2C user interface for portals
2. Enable JavaScript and page layout versions in Azure Active Directory B2C
3. JS Password Validation
4. Customize the look and feel of your Azure AD B2C page

If you read the B2C documentation, it’s strongly noted not to use JS libraries outside of the libraries native to B2C. I opted to keep my solution as simple as possible to avoid additional security gaps.

To get this working, I followed the steps outlined in link 1. There I created all of the needed assets in the Portal Management section of the Power Pages environment. Next, I used the content from link 3 to update the Web Template that I created in the previous step. After that, I updated the Web Template to include the div noted in link 4; this is extremely important and can’t be skipped. The last part of the process is to update the B2C user flow policy to reference the page created in step 1.

Here is a copy of my Web Template file from Portal Management.

<!DOCTYPE html>
<html>
<head>
<style>
      /* Style all input fields */
      input {
        width: 100%;
        padding: 12px;
        border: 1px solid #ccc;
        border-radius: 4px;
        box-sizing: border-box;
        margin-top: 6px;
        margin-bottom: 16px;
      }

      /* Style the submit button */
      input[type="submit"] {
        background-color: #04aa6d;
        color: white;
      }

      /* Style the container for inputs */
      .container {
        background-color: #f1f1f1;
        padding: 20px;
      }

      /* The message box is shown when the user clicks on the password field */
      #message {
        display: none;
        background: #f1f1f1;
        color: #000;
        position: relative;
        padding: 20px;
        margin-top: 10px;
      }

      #message p {
        padding: 10px 35px;
        font-size: 18px;
      }

      /* Add a green text color and a checkmark when the requirements are right */
      .valid {
        color: green;
      }

      .valid:before {
        position: relative;
        left: -35px;
        content: "✔";
      }

      /* Add a red text color and an "x" when the requirements are wrong */
      .invalid {
        color: red;
      }

      .invalid:before {
        position: relative;
        left: -35px;
        content: "✖";
      }
    </style>
</head>
<body>
 <!--this div is the most important part of the process--> 
   <div id="api"></div>
    <div id="message">
      <h3>Password must contain the following:</h3>
      <p id="letter" class="invalid">A <b>lowercase</b> letter</p>
      <p id="capital" class="invalid">A <b>capital (uppercase)</b> letter</p>
      <p id="number" class="invalid">A <b>number</b></p>
      <p id="length" class="invalid">Minimum <b>8 characters</b></p>
    </div>
    
    <script>
      var myInput = document.getElementById("password");
      var letter = document.getElementById("letter");
      var capital = document.getElementById("capital");
      var number = document.getElementById("number");
      var length = document.getElementById("length");

      // When the user clicks on the password field, show the message box
      myInput.onfocus = function () {
        document.getElementById("message").style.display = "block";
      };

      // When the user clicks outside of the password field, hide the message box
      myInput.onblur = function () {
        document.getElementById("message").style.display = "none";
      };

      // When the user starts to type something inside the password field
      myInput.onkeyup = function () {
        // Validate lowercase letters
        var lowerCaseLetters = /[a-z]/g;
        if (myInput.value.match(lowerCaseLetters)) {
          letter.classList.remove("invalid");
          letter.classList.add("valid");
        } else {
          letter.classList.remove("valid");
          letter.classList.add("invalid");
        }

        // Validate capital letters
        var upperCaseLetters = /[A-Z]/g;
        if (myInput.value.match(upperCaseLetters)) {
          capital.classList.remove("invalid");
          capital.classList.add("valid");
        } else {
          capital.classList.remove("valid");
          capital.classList.add("invalid");
        }

        // Validate numbers
        var numbers = /[0-9]/g;
        if (myInput.value.match(numbers)) {
          number.classList.remove("invalid");
          number.classList.add("valid");
        } else {
          number.classList.remove("valid");
          number.classList.add("invalid");
        }

        // Validate length
        if (myInput.value.length >= 8) {
          length.classList.remove("invalid");
          length.classList.add("valid");
        } else {
          length.classList.remove("valid");
          length.classList.add("invalid");
        }
      };      
</script>
</body>
</html>

The idea behind this was to keep it as simple as possible and to get a basic example created. Yes, you can store the file in blob storage, but I wanted to keep all portal parts close together and avoid added complexity. (not that creating this page in Portal Management was easy)

Azure Runbook Job Name error: Token request failed..Exception

When you move from a SharePoint on-prem environment to SharePoint Online, you lose the server-side environment you’d normally use to run PowerShell scripts or tasks to interact with SharePoint. In my opinion, and please correct me if I’m wrong, the closest thing to a server-side environment in a cloud environment is Azure Runbooks or Azure Function Apps. I went with Azure Runbooks due to its ability to handle long-running tasks.

The error I recently encountered in my runbook was: runbook name error: Token request failed..Exception . At first, I thought there might be something wrong with the way I was connecting to Keyvault, but that wasn’t it. Next was my connection to SharePoint, this is handled using a SharePoint-generated client ID and secret. Oddly enough, I had just updated this a few months back, so it wasn’t an obvious candidate for a failure point.

I went to my target SharePoint site, created a new set of credentials using siteName/_layouts/15/AppRegNew.aspx and siteName/_layouts/15/appinv.aspx. After creating the credentials, I went back to the runbook and plugged them in, and it worked!

Long story short, if you get this error: Token request failed..Exception try creating a new client ID and secret and see if it helps clear things up.

You can also use this script to test your client id and secret. Connect-PnPOnline | PnP PowerShell

$siteUrl = "https://taco.sharepointonline/sites/burrito"
$testConn = Connect-PnPOnline -Url $siteUrl -AppId "1111-2222-3333-4444-555555555555" -AppSecret "X3tssvCebdl/c/gvXsTACOajvBurrito=" -ReturnConnection
$list = Get-PnPList "Tacos"
Write-Output $list

Flow Power Automate and SharePoint Required Fields

On the surface, this request sounded super simple and straightforward. “we need to copy files from a SharePoint library to Blob storage.” Simple enough? Well, yes, but the SharePoint library has a couple of required fields and a Flow is triggered by an action.

Consider what I’m outlining below to be version ONE of the process. In the near future, I will update this post with a slightly more resilient solution.

My SharePoint library has a required field titled DesinationFolder

Context of what I’m doing in the Flow:
Trigger: When files is created in a folder
When a file is added to a library the flow is triggered
Get file metadata
File Identifier: Use File identifier from the step above
Get file properties
Id: Use the ItemId from the previous step
Initialize variable
Name: vCheckedOut
Type: Boolean
Value: Checked out (field from Get properties)
Initialize variable
Name: vFolderPath
Type: String
Value:
Condition
vCheckedOut is equal to true
Yes:
Do until
vCheckout is equal to False
GetFileProperties
Set variable
Name: vCheckedOut
Value: Checked out (value from the Get file properties above)
No:
Set variable
Name: vFolderPath
Value: FolderPath (SharePoint field)

Compose
/blobfolder/vFolderPath (variable)
Create blob