How to build a custom connector to retrieve data from sharepoint ?

[bouillons]

Hi, I have a scenario where I have a bunch of related lists in sharepoint online. For example a list with our Point of Sales addresses, another one with the opening hours of each Point of Sales, another one with the employees, etc...

Our finance department would like to access this info programmatically for some of their reporting needs. One alternative is to tell them to use the sharepoint api and get the data from each list, but I'm looking to offer them an easier solution and my idea was to create a custom 'Point of Sales' connector that has a few simple operations such as /getallpos to get the all the consolidated data in a single call, or /getpos/{posid} to get the info of a single point of sales. This is all internal to our tenant, but I do need to secure some of the data, so I also want to do some authentication of who is calling my connector, because I don't want to give everybody access to the underlying sharepoint lists.

Is a custom connector the right solution for this scenario, or are there better approaches ? Has somebody built a similar scenario sample that I can use to get started ? I've seen a lot of samples accessing external api's but haven't found one that connects to sharepoint.

Stephane

Stephane

[powercorner]

Hello Stephane I think your approach with a custom connector doesnt make sense here.

So what I understood is that you have some sharepoint lists like "Point of Sales" and so on...

First of all, is your sharepoint on prem or is it sharepoint online?

If you need to get access to the sharepoint list you are completely right, you could give your finance department rights to access the list and call the sharepoint rest api.

When it comes to securing data you should secure it on the list itself and not inside the flow. 

But let us start form the beginning, when we clear thes questions we will find a solution for you:

SP online or Onprem?

What kind of reports? Excel? PowerBI?

To the finance guys need to get access to the whole data?

What means programatically? Do they use it in some code? PowerShell or Javascript? 

if you do not give everybody permissions on the Lists, you should not have the problem to audit the access. 

Is this still a Power Automate topic? 

I feel that you trying to access SharePoint data from some other code to make reports.

This is more a SharePoint topic and how to secure the SharePoint for your usecase?

Tell me more, I am curious to help you 🙂

With regards,

Kevin

[bouillons]

It's SP Online. But it shouldn't matter does it ? If my data was in SQL, I'd still want an API in front of it with operations that make sense to the consuming client ? I want a simple query that gets data from different sources at once. It just so happens that in my case the data sits in SharePoint.

When I say programmatically, I want a downstream system to be able to request data about a point of sales (preferably via a web api call).

I will give the client (user in our tenant) the rights to access the underlying data, without giving open access to everyone. If I were to word it differently:

http://myappapi/getallpos ---> get the data from different sharepoint lists (or whichever datasource the data resides in) & return as one result

http://myappapi/getpos/5 ---> get the data from pos nr 5 and return it to the client

What they do with the data in their own application doesn't really matter to me. Just display it in a custom app (for example (SAP Fiori), use it in a report or whatever their need is.

I've seen other custom connector examples that get information from github, it's just that in my case the data sits in sharepoint within my own tenant. Makes sense ?

[powercorner · Accepted solution]

Good morning,

Okay now I got a picture.

Let me come to your first question.

It is making a difference if you are using SPO or SP onPrem, cause you would need to establish a connection to your onprem environment via a gateway to fetch data from your SP onPrem. With SP Online you can directly call the SP REST API without entering any firewall secured environments.

But its good that we are talking about SPO!

I also now understood your usecase.

I would say that Power Automate is the wrong technology for your usecase.

I will explain later why I think its not the best idea, but first I would try to show you my idea how

I would build this if I needed to.

So if you want to create this with Power Automate I would concider to do the following:

I would create a flow that will represent your API, you would start with a request trigger (https://flow.microsoft.com/fr-fr/blog/call-flow-restapi/) so your flow gets an rest endpoint.

The trigger is a post endpoint and you can define your JSON Schema. I would give the endpoint the name of your "function" (eg. getallpos or getpos or something else) so the flow knows what to do.

Now you could call your SharePoint lists to fetch the data based on the info you get from the trigger body.

You would need to to some merging operations to build a json that can be send back to the requester.

So you might need some foreach loops etc. It could look like this:

Now you could save the flow and call the endpoint to get the data you requested.

This is working, buuuuut... we have some problems here.

So first the loops inside the power automate are reeeeeally slow. So when you start to merge data from different SharePoint lists and parse your json manually, it will tak you ages for big datasets (lets say bigger then 250 items) So it might happen that your client will run into a timeout when calling the rest endpoint of your flow. In addition your client would need an power automate licensed account. And I am not talking about the E3 lisences, I talk about the per Flow or per User plan. 

So all together, yes it is possible, but its not having a good performance and its expensive.

So what are your alternatives?

1. A custom connector itself cannot help you, cause its is not possible to give a custom connector logic, which would give you data from differrent lists at once.

2. Another posiblity is to do this in Azure with a logic app (https://docs.microsoft.com/de-de/azure/logic-apps/logic-apps-overview). Its technically the same. The difference is that you do not need a power automate licensed account in order to call the flow. The performance is still bad (maybe it could be better cause you could use javascript to process your sharepoint items parsing a json), but you could have this at least less expensive.

3. So the cleanest way to implement your a good solution for you would building your own web api. So I would consider doing it with Azure functions. https://docs.microsoft.com/en-us/learn/modules/build-api-azure-functions/ You could easily build up your logic inside the function and then make the endpoint available for your client. This would be clean, not expensive and the performance is much better.

Let me know if my answer was clear or if you need any further assistance on the other topic, cause we are leaving the power automate scope here.

With regards
Kevin

[bouillons]

Thanks Kevin for spending time and effort to give a clear explanation, it is very much appreciated.

Stephane

[powercorner]

you are very welcome 🙂

[bouillons]

I implemented the single point of sales get request. Works like a charm, and quite fast as well 🙂

I also have a functional GetAllPOS version, but the Apply for Each is horribly slow. I'm still trying to optimize, but haven't got it to respond below 2 minutes yet.

Stephane