Send an email with SPHttpClient

Question

I'm working on a web part for SharePoint 2016 on-prem and I want to send an email from the current user. I cannot use @pnp/sp library as it's not supported with TypeScript 2.2.2 and I'm unable to upgrade it. I'm using SPHttpClient post method, but it gives me error 400:

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

const siteUrl = this.context.pageContext.web.absoluteUrl;
const emailUrl = siteUrl + '/_api/SP.Utilities.Utility.SendEmail';

const reqOptions: ISPHttpClientOptions  = {
  headers: {
    "Accept": "application/json;odata=verbose",
    "Content-Type": "application/json;odata=verbose"
  },
  body: JSON.stringify({
    'properties': {
      '__metadata': { 'type': 'SP.Utilities.EmailProperties' },
      'To': { 'results': ['email@email.com'] },
      'Body': 'Ignore this test email.',
      'Subject': 'Invoice Uploader Test Email'
    }
  })
};

this.context.spHttpClient.post(emailUrl, SPHttpClient.configurations.v1, reqOptions)
  .then((response: SPHttpClientResponse) => {
    console.log(`Status code: ${response.status}`);
    console.log(`Status text: ${response.statusText}`);

    response.json().then((responseJSON: JSON) => {
      console.log(responseJSON);
    });
  })
  .catch((err) => {
    console.log(err);
  });

What is the corect syntax of such request?

Answer 1

You need to add an additional header, odata-version and set it to 3.

This error happens because SPFx's built-in SPHttpClient uses the odata-version header whose value is set to 4.

So, simply change it as below and check:

const reqOptions: ISPHttpClientOptions  = {
      headers: {
        "Accept": "application/json;odata=verbose",
        "Content-Type": "application/json;odata=verbose",
        "odata-version":"3.0",
      }, 
      // rest of your code
}

Referenced from:

1. Suppressing SharePoint REST metadata using odata=nometadata fails

2. Consider making HttpClient features opt-in