Extend Power Automate Logging

1. Power Automate has a Connector to query other Power Automate environments to list, update flows,...
2. PowerShell to examine Flow/Power automate

https://www.cloudsecuritea.com/2019/09/generate-an-overview-of-all-microsoft-flows-with-powershell/

Use postman to Interact with an API - get the bearer token first.

App Insights for Power Platform - Part 9 - Power Automate Licencing

Overview:  Licencing is extremely complicated, but there are threshold limits that are being reduced at the moment, August 2023.  

O365 users get get the lowest priority profile, can only run the standard connectors, and have a "request" limit of 6,000 requests per day.

What is a Request?

Each flow consists of a combination of triggers, actions, and responses when cloud flow is run, the instance walks thru the actions such as Create a SharePoint list item, setting variables, 

What counts as a Power Platform Request

"Here are some guidelines to estimate the request usage of a flow.

• One or more actions run as part of a flow run. A simple flow with one trigger and one action results in two "actions" each time the flow runs, consuming 2 requests.

• Power Automate Flows, by default, run in the context of the Flow Owner.  The "actions" are worked out against the Flow Owner.

• Every trigger/action in the flow generates Power Platform requests. All kinds of actions like connector actions, HTTP actions, built-in actions (from initializing variables, creating scopes to a simple compose action) generate Power Platform requests. For example, a flow that connects SharePoint, Exchange, Twitter, and Dataverse, all those actions are counted towards Power Platform request limits.

• Both succeeded and failed actions count towards these limits. Skipped actions aren't counted towards these limits.

• Each action generates one request. If the action is in an apply to each loop, it generates more Power Platform requests as the loop executes.

• An action can have multiple expressions but it's counted as one API request.

• Retries and additional requests from pagination count as action executions as well."

Here are my thoughts which seem to differ from the MS notes provide above: Not all Actions count as a request, If i look at the Power Automate Analytics it gives me a break down on the API calls to understand the "Request" counting.  Basically any action that does an API call when run adds to the request count.  

Guide for planning for limitations:

• O365 users get 6k request per days
• Dynamics and most per user plans get 40k requests per day.
• As a rough guide, I count simple workflows as 3 requests average, medium as 7 requests, large can be over 100 so it is better to build the workflow and from the analytics you can get the number of requests per day.
• For each flow multiply by the estimated number of calls
• Understand who the quest is attributed to (either the user or the owner of the flow, the requests are counted against the flow owner unless the flow use a pay per flow model.)

Example: to calculate billable actions/billable requests

I have a single Flow running against my O365, the flows has a Power Apps trigger, then creates a new list item and lastly responds to Power Apps.

1 Cloud flows that has 3 billable actions run 5 times will result in 15 billable actions.

I have 6k per 24 hrs on an O365 licence, most of the other licences such as Power Automate premium, an account has 40k requests per 24 hours.

I could run the flow 1,200 times in 24 hrs under an O365 licence.

Series

App Insights for Power Platform - Part 1 - Series Overview 

App Insights for Power Platform - Part 2 - App Insights and Azure Log Analytics 

App Insights for Power Platform - Part 3 - Canvas App Logging (Instrumentation key)

App Insights for Power Platform - Part 4 - Model App Logging

App Insights for Power Platform - Part 5 - Logging for APIM 

App Insights for Power Platform - Part 6 - Power Automate Logging

App Insights for Power Platform - Part 7 - Monitoring Azure Dashboards 

App Insights for Power Platform - Part 8 - Verify logging is going to the correct Log analytics

App Insights for Power Platform - Part 9 - Power Automate Licencing (this post)

App Insights for Power Platform - Part 10 - Custom Connector enable logging

App Insights for Power Platform - Part 11 - Custom Connector Behaviour from Canvas Apps Concern

App Insights for Power Platform - Part 6 - Power Automate Logging

Note: Announcement 23 Aug 2023 - integration of Power Automate telemetry data with Azure Application Insights.

Series

App Insights for Power Platform - Part 1 - Series Overview 

App Insights for Power Platform - Part 2 - App Insights and Azure Log Analytics 

App Insights for Power Platform - Part 3 - Canvas App Logging (Instrumentation key)

App Insights for Power Platform - Part 4 - Model App Logging

App Insights for Power Platform - Part 5 - Logging for APIM 

App Insights for Power Platform - Part 6 - Power Automate Logging (this post)

App Insights for Power Platform - Part 7 - Monitoring Azure Dashboards 

App Insights for Power Platform - Part 8 - Verify logging is going to the correct Log analytics

App Insights for Power Platform - Part 9 - Power Automate Licencing

App Insights for Power Platform - Part 10 - Custom Connector enable logging

App Insights for Power Platform - Part 11 - Custom Connector Behaviour from Canvas Apps Concern

Overview:

• Power Automate holds it own set of logs and history.  While Power Automate's internal logging is good and useful, it does not push logs into App Insights or Log Analytics for central monitoring.
• You can manually export Power Automate logs from Power Platform and import them into Log Analytics, using the "Data Export" option.

• You can use the built in action to log directly to Azure Log Analytics with a flow.  Here is a 4 min recording outlining the approach in a Power Automate Flow.

• Or you can create an Azure Functions that you can use to write to App Insights, below is a simple recording of the function (this is recording aims to remove complexity so there is no VS Code or publishing.

Function to write into App Insights Logs

#r "Newtonsoft.Json"

using System.Net;

using Microsoft.AspNetCore.Mvc;

using Microsoft.Extensions.Primitives;

using Newtonsoft.Json;

public static async Task<IActionResult> Run(HttpRequest req, ILogger log)

{

    string requestBody = await new StreamReader(req.Body).ReadToEndAsync();

    dynamic data = JsonConvert.DeserializeObject(requestBody);

    int eventId = data?.eventId;

    string errType = data?.errType;

    string errMsg = data?.errMsg;

    string correlationId = data?.correlationId;

    string workflowId = data?.workflowId;

    string workflowUrl = data?.workflowUrl;    

    string flowDisplayName = data?.flowDisplayName;

var custProps = new Dictionary<string, object>()

{

    { "CorrelationId", correlationId},

    { "WorkflowId", workflowId},

    { "WorkflowUrl", workflowUrl},

    { "WorkflowDisplayName", flowDisplayName}

};

using (log.BeginScope(custProps))

{

    if (errType=="Debug") 

    {

        log.Log(LogLevel.Debug, eventId, $"{errMsg}");   

    }

    else if (errType=="Critical")

    {

        log.Log(LogLevel.Critical, eventId, $"{errMsg}");  

    }

    else if (errType=="Warning")

    {

        log.Log(LogLevel.Warning, eventId, $"{errMsg}");   

    }

    else if (errType=="Trace")

    {

        log.Log(LogLevel.Trace, eventId, $"{errMsg}");          

    }

    else if (errType=="Error")

    {

        log.Log(LogLevel.Error, eventId, $"{errMsg}");          

    }

    else

    {        

      log.LogInformation($"Event is {eventId}, type is {errType}, and msg is {errMsg}");

    }        

};

    string responseMessage = $"This HTTP triggered function executed successfully. {errType} - {errMsg}";

    return new OkObjectResult(responseMessage);

}

Power Platform Admin Centre:

There is nice analytics inside the Power platform Admin Centre as shown below to examine Flows/Power automate:

The flows can also be reviewed on a per environment basis:

Series

App Insights for Power Platform - Part 1 - Series Overview 

App Insights for Power Platform - Part 2 - App Insights and Azure Log Analytics 

App Insights for Power Platform - Part 3 - Canvas App Logging (Instrumentation key)

App Insights for Power Platform - Part 4 - Model App Logging

App Insights for Power Platform - Part 5 - Logging for APIM 

App Insights for Power Platform - Part 6 - Power Automate Logging (this post)

App Insights for Power Platform - Part 7 - Monitoring Azure Dashboards 

App Insights for Power Platform - Part 8 - Verify logging is going to the correct Log analytics

App Insights for Power Platform - Part 9 - Power Automate Licencing

App Insights for Power Platform - Part 10 - Custom Connector enable logging

App Insights for Power Platform - Part 11 - Custom Connector Behaviour from Canvas Apps Concern

Logging and Monitoring Advanced Canvas Apps

Overview: Most Canvas apps reach back to 3rd parties or internal storage e.g. SQL, Dataverse, blobs to persist data.  In an ideal world we want to be able to identify error and performance concerns and be able to trace quickly.

Scenario: A canvas app performs a search against a custom connector, that goes to an external API, for example search's for Company Numbers from an Open API.

• The annotated diagram, in orange records the button pressed to run the search.  This only shows if the "Upcoming feature", "Enable Azure Application Insights correlation tracing" is enabled.
• A custom connector, in blue, makes  a call to an REST/Open API.
• The last call is to an external API, highlighted in purple, (in this case it was actually a mocked APIM endpoint, but the icon would change it it was totally external such as call API search to the IRS, HMRC, Inland Revenue.

Tip: Always create App Insight Instances using a workspace and not the classic-mode app insights as it is being deprecated by Microsoft in early 2024.

App Insights Understanding:

App Insights setup using the Workspace-based setup (Log Analytics) can be queried in two ways:

• Query thru App Insights
• Query thru the Log Analytics workspace (the Kusto/KQL is slightly different, but it's rather minor)

Tip: If you upgrade from classic to the workspace base app Insights, the log history is still "query-able" as App Insights combines the logs from AppInsights Classic (stored in app insights directly) and the logs stored in Log Analytics.

Tip: Power Automate has a connector to Log Analytics so it's good to use this for flows so you can trace canvas apps using flow journeys.  Most people tend to build a custom connector to a function that uses the AppInsights SDK.  I've used both and they are both valid approaches and shown in the annotated diagram below.

The two options for logging Flows into App Insights.

Note: If you create a new App Insights workspace-based instance remember to update the loggers in all you Azure Services to the new instance (app key).  For example functions, APIM and Service Bus are common components.

Note: You can log to multiple workspace/app insights in a tenant and the correlations will be retrieved so you see the full history, assuming you have permissions to all log sources.

Learning: the instrumentation key for app insights has 3 parts to it: 

1) instrumentation key (basically a unique identified to find and allow logs to be saved into AppInsights, 

2) ingestion endpoint (URL for the log), and 

3) monitoring metric endpoint (URL for metrics/performance counters/live metrics/failed requests/). 

Here is an example and you can see the 3 parts:

InstrumentationKey=2675bxxx-xxxb-xxxx-bf5558009ccf;IngestionEndpoint=https://uksouth-1.in.applicationinsights.azure.com/;LiveEndpoint=https://uksouth.livediagnostics.monitor.azure.com/

Runas on Flows

Overview: If I use a connection in a Canvas App, the signed in user uses their own permissions and the connector as as the signed in user.  

Problem: I wish to run a flow as a specific user and not the users calling the flow from the Canvas app.

Hypothesis: I wish to call logging connector into Log Analytics, so I have created a flow, If I use the Power Apps V2 connector, it offers and option to run in another users context.

Resolution: Open the Workflow, ensure you are using the Power Apps V2 trigger, then...

Here I use the Scopes to perform a Try Catch finally set of logic

Tip:  most people tend to use a custom connector to push the error message into a function from the Workflow, the function app uses the App Insights SDK and logs the workflow error.

Simple C# code to write to App Insights using the SDK. 

#r "Newtonsoft.Json"

using System.Net;

using Microsoft.AspNetCore.Mvc;

using Microsoft.Extensions.Primitives;

using Newtonsoft.Json;

public static async Task<IActionResult> Run(HttpRequest req, ILogger log)

{

string requestBody = await new StreamReader(req.Body).ReadToEndAsync();

dynamic data = JsonConvert.DeserializeObject(requestBody);

int eventId = data?.eventId;

string errType = data?.errType;

string errMsg = data?.errMsg;

string correlationId = data?.correlationId;

string workflowId = data?.workflowId;

string workflowUrl = data?.workflowUrl;

string flowDisplayName = data?.flowDisplayName;

var custProps = new Dictionary<string, object>()

{

{ "CorrelationId", correlationId},

{ "WorkflowId", workflowId},

{ "WorkflowUrl", workflowUrl},

{ "WorkflowDisplayName", flowDisplayName}

};

using (log.BeginScope(custProps))

{

if (errType=="Debug") { log.Log(LogLevel.Debug, eventId, $"{errMsg}"); }

else if (errType=="Trace") { log.Log(LogLevel.Trace, eventId, $"{errMsg}"); }

else { log.LogInformation($"Event is {eventId}, type is {errType}, and msg is {errMsg}");}

};

string responseMessage = $"This HTTP triggered function executed successfully. {errType} - {errMsg}";

return new OkObjectResult(responseMessage);

}

More Info:

Reza Dorrani has a great recording showing running Power Automate flows using elevated/shared accounts.

Canvas Apps Workflow logging linkage

Overview:  Power Automate has good monitoring and analysis within the product, and Canvas apps use instrumentation to App Insights and allow for custom tracing.  The issue is linking Canvas app logs to a called workflow.  In this video (2min), I discuss linking Traces in Azure App Insights with flows run on Power Automate.

By passing the the workflow runs workflow back to the calling canvas app, a deep link will allow support to follow a users activity including drilling into the flows being called.

Add additional logging to Azure Log analytics to a custom table within your flows:

Power Apps Portal and Power Automate licencing thoughts

Update: 13 August 2023 - Power Apps Licencing has change considerably since this post, for example here is updated information on Power Automate licencing.

My Technical Working Notes for Microsoft Technology: App Insights for Power Platform - Part 9 - Power Automate Licencing (pbeck.co.uk)  A major change in naming and cost has been release August 2023.

Overview:  The Total Cost of Ownership (TCO) is key to any project.  I recently was asked about a project that wanted to use Power Apps for external user access, the data is in the dataverse/CDS) and their are tons of workflows.  The cost of buying a per app licence for external users is a non-started (without volume discount $5 or £3.80 per user per month  and the only viable options left are:

Design by Cost:

Write the front end using free to distribute front end application (i.e. ReactJs, Angular, C#, Flutter, Blazor,...) and all the flows using the per-flow licencing model.  Per-flow licencing is crazy expensive as it is per flow and my users have lots of flows when the login once a year.  So per flow is also not an option with a custom front-end.  At Ignite 2022, Microsft announce a new Power Automate Embedded SDK with pay as you go pricing, this may be a good option, but's its untested.

The $5/month/app plan doesn't really work as users login over the last few months of the year and all users would need to be licenced all year around so $60 is way too high.  The Power Apps Pay-as-you-go Plan allows costs $10/£7.45 per user that logs in during a month.  So in my case an average user logs in 2 times in a year with the monthly consideration, so i'm still looking at $20 per year.

User/Per App/month: £3.80

User/Month (multiple apps): £15.10

Active User/app/month Pas-as-you-go  £7.45

Power Apps Portals/Power Pages/Dynamics Portals is my last hope.  The licencing is based on per login per 24 hrs.  So a user that logs in three times in a 24 hr period is considered 1 licence.  If the user logs in on 4 different dates at any point in the year, the client is changed for 4 logins.  Need to buy the licences in advance each month.  Sold in blocks, the smallest being 100 logins in a month.  At the lowest levels, cost is $2 per 24 hour login, but this reduces to a much lower cost relatively quickly.   With our expected numbers, we'd get onto Tier 3, and the cost per login is $0.70 per login.  If an average user logs in 4 times a year on separate dates, our cost is basically $2.80 per user per year.

Note there is also a Page Portals Capacity licence required.  We are expecting an average of 175k page views, which cost a further $200.

13 Oct 2022: Licencing for Power Pages change yesterday, 1) monthly anonymous active users 2) monthly authenticate active users.  Prepaid is cheaper than pay as you go, assuming you get you numbers right.  https://www.microsoft.com/en-us/licensing/news/power_pages_general_availability#:~:text=Today we are announcing licensing and pricing details,to purchase through prepaid subscription and pay-as-you-go plans.

Summary: In this case, Power Pages is the best option.  

Custom HTTP connector in Power automate to POST x-www-form-urlencoded data

Problem:  As part of my OAuth process I need to swap and authorisation code for an Access Token using an API, the issue is that I need to get the token into PowerApps.  

Initial Hypothesis:  Initially I created an Azure Function that does the API post as it was the easiest.  But I reverted and thought it must be easier for me to have fewer working parts and as my solution used Power Automate and I've previously used Power Automate with the HTTP custom connector I'd use the same approach.  It proved fairly tricky to get the HTTP connector to work but with some playing around and clarification of my thinking it became rather straight forward.

Firstly, I need to ensure the API is working, so I use Postman:

Postman POST request using form-urlencoded.

When I get the 200 response, I wanted to see the underlying HTTP traffic so I opened Fiddler:

Solution: From the raw HTTP trace, I realised I needed to post the body in Power Automate in the correct format.  Key value pairs for parameters and separate with an Ampersand.  Also, Url's need to be escaped/encodes, in C# there are functions to encode and decode.  I needed to do the encoding using Find() and Replace() methods (sic).  From Power Automate, I return the Access token, refresh token and other info back to Power Apps.

More Info:

Uri.UnescapeDataString(String) Method (System) | Microsoft Docs

Understanding HTML Form Encoding: URL Encoded and Multipart Forms - DEV Community

Generating a pdf from a word binary - Power Platform

Overview: Move a word document into a pdf stream in a Power Automate flow.

Solution: I am triggering a flow when a word document is created in Dataverse.  I get the word document in a stream and use OneDrive for Business (OD4B) to persist the docx to OneDrive.  I use the Power Automate Word for Business connector to convert the docx in OD4B into a pdf binary stream in my flow.  

Tip: The Location (OneDrive site collection) gets converted to a guid, so if you need a separate site collection for OneDrive or SharePoint, you can use the MS Graph and I believe this URL also works: 

https://radimaging.sharepoint.com/personal/paulbeck/_api/v2.0/drives.

Power Automate Notes

What is Power Automate?
Power Automate previously called Flow.  Power Automate contains "Flows".  Power Automate is workflow including RPA options, refered to a Power Automate Desktop (PAD).  Power Automate is a workflow engine that is based on Azure Logic Apps.  Powerful extendable workflow solution for low code automation.  Allows workflows to be easily automated with 3rd part systems e.g. SAP.

Used for:

1. Personal Workflows e.g. I send an email to all people that have not update the DevOps Scrum board on a in the last day as a scrum master.
2. Business Process e.g. Holiday request form.  If more than 10 days, need senior manager approval.  Generate RFP based on an event.  Historically, used K2 or Nintex or WCF workflows for business processes.
3. Integration: e.g., move twitter posts into my warehouse for data-mining later.

A key concept is who shall the flow run as, a user or a service principal.  Setup a Service Principal in Power Automate » Benedikt's Power Platform Blog (benediktbergmann.eu)

Flows run against the owners account for calculating allowable usage (default), it is common practice to use a service account (normal AAD account with user and Pswd) to own specific flows.  A service account is a normal user account from AAD/Entra's perspective.  A dedicate account ensures that when a specific user leaves your business, the flow continues to run.

Img 1. Usage limits in Flows are counted against the flow owner.

Agree Power Automate Standards:

1. Flow Names: start with a verb  format: Verb + What the Flow does + (trigger) e.g. "Get Tax Rates (Instant)".  I like to also prefix with the Company and Project, but feel free to have a standard to suit your business.  e.g. EY-USTax Get State Taxes (Instant) or EY-USTax Get All US State Tax Rates (Scheduled) or Get SalesForce Data.  Optional, for project specific workflows I also prefix witht he project name e.g. USTax-GetTaxRate. 
2. Description: Short description to help readers understand what the flow does.
3. Actions: Leave the Action desc and add info e.g. Compose: Tax Note.
4. Variables: prefix with "v" e.g. vTaxTotal in camelCase.  e.g. vUserAge.
5. Error handling & Logging: Catch errors and log into to App Insights via an Azure Function or Log using the built in Azure Log Analytics Action.  More logging means better traceability.
6. Scope: Add scope actions for try catch logic.  Add multiple actions inside a "Scope" Action
7. Terminate the flow with the Terminate Action if the flow has failed.
8. Environment Variables: Great for logging as I go thru DTAP.  Also see.
9. Connection Reference Name: Agree a format, does this flow run as  user or as a specified user.
10. Loop Sparingly, use First() for performance.
11. Owner: I like to use a service account in dev, it's a good idea to add tech owners as when it needs updating to support and easily find who they should talk too.  Understand who you are running the flow as, this ties to licencing but is critical.  You need to know you Actions and licencing limits on a project.
12. Comments:  Im not a huge fan as the naming should make most flows make sense/self documented, but for tricky logic, comments are great.  Agree a standard.
13. Retry policy: What happens if an action fails, do you want to try again?  

I borrowed a lot of the standards from "Matthew Devaney"

I found this document later - it is excellent. by Prasad Athalye - Best Practices for Power Automate(Microsoft Flow) Development

Licencing:

1. Seeded licence is part of O365.  Use standard functionality such as standard connectors without needing to pay more for advance.  The advance/premium connectors are not part of the O365 licence.
2. Per User licence -  Allows the  user $15 retail, can get discount with bulk and can use the advanced connectors & on-prem. gateway.  Many users need multiple workflows, normally personal workflows.
3. Per User RPA licence - same as above but also has amazing RPA capabilities.
4. Per Flow/Process - $100 per process per month, min 5 flows per month licences.  Anyone can use as part of the process.  Use for few people but process does a lot of workflows.  Can add a process one at a time after the first 5.

Licencing MS page
Power Automate has some licence add-ons available: AI builder and an unattended RPA add-on.
"Power Apps licenses will continue to include Power Automate capabilities", I don't know what is included but I assume it means any connector I can use in Power Apps, assuming I'm in Power Apps I can make Flows for.

Build workflows:

• Can get a dedicated IDE tool for Power Apps or use the browser (which i always use).
• There are over 350 connectors (in both standard and premium) and you can always use a custom connector to any OpenAPI (Swagger) endpoint.
• Templates have some examples and often help as a starting point to make your own custom Flows in Power Automate.
• Easy clear tracing so you  can see what part of the workflow is working and where you fail, and you can drive into the issue.  Super easy to use.
• Example of an Instant Cloud flow triggered by a canvas Power App...

Query a Dataverse table in a Flow using OData

ParseJSON is fantastic for converting Open API/OData/JSON into an object

Extending - break out for programmatic control, I use C# Functions from my Flows and call them via HTTP triggers.

Retrieving  a row from the Dataverse custom "Subject" table.

Robotic Process Automation (RPA):

• Also known as UI Flows within Power Automate.  Microsoft have purchase and integrated Softomotive for UI flows to add WinAutomation.
• Attend (user logged in) and unattended version (complete tasks without manual intervention)
• Can have multiple instances
• API is generally better than using RPA as it is versioned and generally not changeable, whereas using a website, they website can be changed causing the RPA flow to fail.  Useful for instance when the RESP API is incomplete.
• Recording tool for creating UI flows - Web use Selenium to record.
• 3 Types: 1) Windows /Desktop/Screen reader and 2) web/website (Selenium) and 3) WinAutomation (covers both Windows and Web, easy to use but not as full featured yet).
• WinAutomation has a drag and drop IDE, has error handling.
• UI flows are well priced.  Also get AI builder credits with UI flow licences.
• "Power Automate Per user plan with attended RPA to use UI flows and WinAutomation" Microsoft.

AI Builder:

Cognitive builder e.g recognize forms and extract data. E.g. receive invoices and add to accounting SaaS software.

Other: Zapier is a good tool for end user automation.  Easier than Power Automate but not as structured.  I'd use Zapier to automate in small businesses without O365 or flow licencing and allow end users to do it themselves.

Problem Solving:

Problem:  Another developer created a Flow I need to use from a Canvas page inside a model app.  The Flow is showing up when i say add but i get the error "Unable to add flow"

Initial Hypothesis: The flow is owned by another developer having ownership and the connection is done thru their account, take ownership and change the Connection (Dataverse connection in my case)

Resolution: To use an existing flow, you need: 1) flow in same solution as the canvas app, 2) Ownership and the connection string needs to be switched to the new developer

Problem: Migrating solutions between environments, all the workflows fail when they use the Dataverse connector with 403 errors. Tracing the flows, I can see the error  "Flow client error returned with status code 'BadRequest' and details {error: code: 'XrmApplyUserFailed... UserNotinActiveDirector ... does not exist in user tenantId"

Problem: Using the service Principal account needs to be registered in the new Dataverse environment.

The connector issue was fixed, we had to recreate the connection from scratch making sure it was set up with a/the service principal. Then we added the registered app into the environment as an application. user.

PL-900 Microsoft Power Platform Fundamentals Beta Exam

Overview:  This morning, I took the PL-900 Beta exam; it is seriously tough.  I don't think I passed but let us see as the results come out 2 weeks after the beta is closed.

My Thoughts: The exam covers three products: Power BI, Power Apps & Power Automate (formerly called Microsoft Flow) but is extremely wide-ranging on relying Microsoft technology.  You really need to have worked in detail with the products as the questions were not straight forward and often combine multiple related services/products.

What I learnt:  You need to know the 3 products well, and how the interact.  My connectors knowledge could be better, CDS comes in a lot, and my Dynamics 365 knowledge is lacking.  There were some Cognitive service questions that I was not ready to deal with.  It is a good test of knowledge, that has helped me realize I have holes in my knowledge on the Power Platform.

The exam itself:  Microsoft exams become easier as you learn how they ask questions, I found some of the language and questions difficult to follow.   What is the question actually being asked but this is pretty standard in a lot of Microsoft certification exams.

I did the exam remotely using Pearson/VUE software, which is great.  No need to book and go to a test centre.  They check your environment and identification and watch you throughout.  I got a warning for reading aloud, which until that point was awesome as the wording of the questions is not the easiest to understand, but it makes sense as people could record the questions using audio for cheating with brain dumps.

Summary:

• I am convinced that I failed PL-900.  
• I learnt a lot preparing for the exam and it was a good experience.
• I need to look at Dynamics & Cognitive Services in more detail.
• Remote exams are awesome and secure the way they are done & don't talk to yourself during the exam.
• I've missed taking Microsoft and other certifications.

Power Platform Notes - Power Apps, CDS, Power BI & Power Automate

Power Apps

Variables:
Microsoft Docs "PowerApps and Excel both automatically recalculate formulas as the input data changes".

• Contextual variables - scoped at a screen level
• Global variables - scoped app level
Fx> Set(MyUniqueClientNo, 12)

Functions:
Fx> UpdateContext({MyTimesheetId: 34})

Tip from Shane Young:  Note the setting variable may be the reference, so for a control use:

Fx> UpdateContext({MyTimesheetId: txtTimesheetId.Text}) not
Fx> UpdateContext({MyTimesheetId: txtTimesheetId.Text}) unless you want the context to float

Pass a variable to another screen use the Navigate overload, OnSelect property of a button
Fx> Navigate(Screen2, ScreenTransition.None, {TSvar: MyTimesheetId}
MyTimeSheet Id is a contextual variable

If Statement:
Fx> If(MyUniqueClientNo = 12, lblAns.text = 'yes', lblAns.text = 'No')

Environments:

1. Power Platform allows you to create multiple environments, each environment is connected to you AAD tenant.
2. Policies can be applied to prevent DLP against all environments or specific environments.
3. Use Environments for DTAP, business units, or Extranet vs Intranet.
4. Updated June 2022: Environments can be of type: Default (don't use and rename), Developer, Trial, Sandbox or Production.
5. Each Power App environment can have no CDS/Datavserse or a single CDS/Dataverse connect.

Manged vs Un-Managed Solutions:

Solution are useful for packaging and moving assets between environments or tenants.  Manged restricts who can edit the applications in the solution.  I like to keep each solution with a single app in it.  On large projects, it's a good idea to keep environment variables, custom connectors, cloud flows, apps in separate solutions.  It makes it easier to deploy pieces.    

Managed Environments:

Don't mix up with Managed solutions as I did recently.  Managed environments allow for a host to control all the environments.  You also should use a dedicated host production environments with Dataverse database to control all the environments.  You need to install solution on the host.  Managed environment have no correlation to managed solutions.  You need managed environments is you are going to use Power Platforms simple ALM for App deployment.

ALM:
Power Apps has it's own source control and you can manually export and import entire projects "Export package" not connections are not export as part of the package.  Solutions are the best way to move code between environments.  It's a good idea to use environment variables  Get ADO, more secure, better tooling using solutions over manual exporting code using packages.  Power Apps Build Tools allows for ADO/DevOps integration generally using solutions to deploy.  At a minimum you should have your own dev env (Sandbox or Developer type), a test (Sandbox type) and production (production type env) for any serious app you build.

Add "Power Platform Tools"

Example Power Platform ALM deployment using DevOps - 5 environments

Update Jan 2022: 

Solutions are used to in Power Apps to package and move code and resources such as flows, env variables, canvas apps, Dataverse tables between environments.  It's a good idea to not use the default environment as everyone has access to the environment.  The DTAP around ALM can get pretty complex and I like to keep it fairly simple.  Connectors can get nasty in packaging.  ADO using AppBuild Tools makes for a good CI/CD solution for Power Apps.

Environment variables are a great way to manage configuration, they can also easily be configure in the pipelines to replace with the appropriate values.  Tip:  Don't ever set the current value in an env var it get carried thru to the next DTAP env.  Also env vars support Azure Key Vault, use it for secrets.

Custom Connectors and getting Connection References correct when using managed environments to deploy code need to use environment variables so they can easily be set for each environment using CI/CD.  It's a good idea to create connections in solutions and use a dedicate Owner account.  Connection references in solutions - Power Apps | Microsoft Learn

There is also a great tool to unpack .msapp solutions for raw review and storage in git.  https://powerapps.microsoft.com/en-us/blog/source-code-files-for-canvas-apps/ for me, it's main use is verifying code and standards and comparing versions.  Post on unpacking solutions.  You can also see how many controls you have in you Canvas app.  MS have the guideline of 500 controls in an app.  

Have a: 

1. Dev environment that is of the "sandbox" type.  Have an un-managed solution that will act as your base canvas app for all new Power Apps.  When you export the solution remember to export as a managed solution and ensure environment variables are emptied before publishing the export.  Good place to backup to a repository such as TFS Azure DevOps/Git.
2. Test env of the type "production" or "sandbox".  Only allow managed solutions to be deployed.  Watch out for custom connectors, I can't get them to deploy correctly in solutions.
3. Prd env must be of type "production".

Manual ALM i.e. Use PowerApps to store Dev versions, Exporting solutions and unpacking managed solutions into UAT and production.  Manual ALM is good even manually moving the applications by hand is simple and safe.  There are backups and manual backups to avoid a source code repository.  I also like the testing framework in Power Apps.  Using the build tools getting full ALM/CI/CD it is easy to then move your Power Platform into a higher ALM CI/CD level using the Power Platform Build tools, DevOps, and PowerShell cmds.  

Update April 2022: Great simple video on ADO for Power Platform 

Licencing:
Updated: Power Apps Licencing Summary as of 30 December 2019

"To run standalone apps, guest users need the same license as users in your tenant."  Microsoft Docs.  

• PowerApps using AAD B2B user (both members and guest) using standalone Power Apps shall require the Power Apps licence (not necessarily Portal Apps).  Steps to Share Power Apps with Guests. 
• SharePoint user interacting with a Power Apps form on a SharePoint list do not require a Power Apps licence.

Coding Standards for Power Apps:

• Microsoft provide a whitepaper as a suggestion for using naming/coding standards.
• Controls and variables should use prefixed Camel case e.g. txtContactEmail
• Data sources use Pascal Case e.g. ContactUsers 
• Screen must be Full names e.g. Edit Contact User Screen as they are read as named by screen readers like JAWS and Microsoft reader.
• Prefix controls and collections (Label is lbl, Textbox is txt, Button is btn, Collection is col, drop down lists are ddl, Form is frm, Group is grp, Gallery is gal, Icon is ico, Images are img, Table is tbl.  I also prefix my components with com.
• Variable naming is: gbl for Global and context variables are var
• Use Containers for layout and groups for control aggregation.
• Use TabIndex so keyboard navigation makes sense.  Use the AccessibleLable over HintText.  Ensure colour contracts and use the approved colour templates stored in global variables.  All fonts, sizing and colouring must come from global variables so the app can be easily changed.  Use the App Checked and complete all identified accessibility issues/concerns.  Test on actual devices and use screen readers.
• Ensure App Insights is setup, capture and log errors, also use the monitoring (maybe not in production).

Power Apps Portals:
Build responsive website using CDS.  Allow anonymous access or implement multiple Identity Providers (IdP) such as AAD B2C, AAD, Google+, LinkedIn.

Updated: 28 July 2018:
Common Data Service (CDS): Comes from Dynamics CRM Sales, pretty much used like CT's in SharePoint.

• Based on Azure SQL & uses CosmosDB with a nice API that support REST/ODatav4;  
• Has Row, field RBAC and uses AAD for authentication;
• Allows Power BI, Power Apps (previously labeled as PowerApps) & Flow (Power Automate - new name since Ignite 2019) to work with CDS (renamed to Dataverse);
• Use Power Query to Import data easily or data flows
• Multiple data source such as SQL Server, Cosmos, files, Excel, Search, 3rd parties such as SAP.
• CDS is not part of the O365 licencing (including E5), you need to get a PowerApps P1 or P2 (Now Power Apps for Users as licencing changed circa Oct 2019).  Note Power Apps licencing included with O365 is extremely limited and for instance does not cover CDS;
• One Power Platform Environment ties to one CDS/Dataverse database
• Any type of data; any type of app.  
• Easy to use; secure.

https://docs.microsoft.com/en-us/powerapps/maker/common-data-service/data-platform-intro

Examples: 

Insert or Update using Patch to CDS:

Patch(

        Vote,

        Defaults('Employee Sentiment'),

        {

            userid: UserID,

            vote: ThisItem.Vote,

            votedate: Now()

        }

    );

Select from CDS:

UpdateContext( { locVotes: LookUp('Vote', votedate = <date>) });

Tip: XrmToolBox is a fantastic tool.  Multiple contributors have added to the client application, there are so many useful features for instance FetchXMLBuilder allows you to query the Dataverse tables.

Power Automate

Updated 11 December 2019:
Microsoft Power Automate (previously called Microsoft Flow, is an user friendly workflow tool/service): Simple workflow engine sitting on Azure Logic App.
Basic business process flows are:

1. Automated Flows - used when event/status change e.g. CDS row status changes
2. Button Flow/Instant Flow - Events such as a click triggers the flow;
3. Scheduled Flow - in effect timer jobs;
4. Business Process Flow - ensures users enter  data consistently (think Windows Presentation Framework) & follows the same steps every time; and
5. UI Flow (preview) - Provides RPA capabilities;

https://docs.microsoft.com/en-us/power-automate/get-started-logic-flow

Building Blocks for Power Automation are:

• Trigger - what starts the workflow, can be manual trigger or an automated trigger
• Actions - ,
• Conditions,
• Data operations, 
• Expressions - basic operations like adding two numbers together, making a string upper case, and
• Flow Type - see the 5 flow types above.

Display directions using Map on a Image control in PowerApps:
https://dev.virtualearth.net/REST/v1/Imagery/Map/road/Routes/driving?waypoint.1=51.525503,-0.0822229&waypoint.2=SE9%4PN&mapSize=600,300&key=<key>
https://dev.virtualearth.net/REST/v1/Imagery/Map/road/Routes/driving?waypoint.1=" & EncodeUrl(txtDriverLocation.Text) & "&waypoint.2=" & EncodeUrl(txtDriverLocation.Text) & "&mapSize=600,300&key=AsR555key