SharePoint Framework POST requests: watch out for OData version incompatibility

This week I've been building a SharePoint Framework web part that queries a Pages list, amongst other things. For reasons that I won't go into, I need to do this by sending a CAML query to the server. The usual way to do this is to send a POST request to the getitems REST endpoint:

[Web URL]/_api/web/lists/getbyid('[List GUID]')/getitems

Where the body of the request contains your CAML query:

'query': {
   '__metadata': {'type': 'SP.CamlQuery' },
   'ViewXml': '<View><Query><Where>...'

To do this the SPFx way, we leave jQuery.ajax behind and use the method. However, when I did this, the server returned an HTTP 400/Bad Request response with the error message:

The property '__metadata' does not exist on type 'SP.CamlQuery'. Make sure to only use property names that are defined by the type.

After a bit of trial and error in Fiddler, I found the problem:

The SPHttpClient class ap…

Getting or Setting Multi-Value Metadata Fields with the REST API

A couple of years ago, I published a series of posts on getting and setting taxonomy field values in SharePoint workflows by using the REST API in custom workflow activities. These custom activities have served me well, but they've always been unable to work with multi-value taxonomy fields. It's time to fix that.

Background As you probably already know, when you add a taxonomy field to a SharePoint list, SharePoint adds a corresponding hidden note field. For example, if you add a taxonomy field named Colours, you actually get:

A taxonomy field named Colours. Depending on whether the column allows the user to select multiple terms, the field accepts values of type SP.Taxonomy.TaxonomyFieldValue or Collection(SP.Taxonomy.TaxonomyFieldValue).A hidden note field, probably named Colours_0.  The hidden note field stores the contents of the field in a term string format. In a single-value taxonomy field, the format looks like this:
And in a mult…

Controlling start options for SharePoint workflows in Visual Studio

When you build a reusable SharePoint workflow, it's useful to be able to control which start options are available. For example, if you only want your workflow to run once when an item is created, it makes sense to disable the "Changing an item will start this workflow" option.

SharePoint Designer provides some handy checkboxes that you can use to control your start options:

However, it's not immediately obvious how you can set these options for a Visual Studio workflow as the options aren't documented anywhere.

To control the start options for a SharePoint workflow in Visual Studio, you need to edit the feature element file that deploys your workflow. Within the feature element file, you need to add properties to the File element that deploys your Workflow.xaml file:

<?xmlversion="1.0"encoding="utf-8" ?><Elementsxmlns="">  <ModuleName="[Workflow Name]"Url="wfsvc/1c…

Applying a Logo to Every Site in SharePoint Online

A quick post today on a fairly common problem - you're given a site collection on Office 365 that has grown organically with hundreds of nested sites, four or five levels deep in places. The various site owners have used many different versions of your company logo, and you want to reintroduce a degree of consistency by applying the same logo to every site in a site collection.

The most efficient way to do this is to run some client-side code from PowerShell. Basically you need to iterate over the subsites of a given site and set the Web.SiteLogoUrl property on every site. The easiest way to do this is to:
Install the excellent SharePointPnP.PowerShell cmdlets.Run a script something like the one below.# UpdateSiteLogos.ps1# Jason Lee 5/12/16
# Variables$rootSiteUrl="https://[tenant][path]"$credentialManagerLabel="ianWilliamsAdmin"$logoUrl="/sites/[path]/SiteAssets/smile.png"
# Recursive function to set site logo on specified site# P…