email content generator service

[spelkey-ucd]

when an admin saves an email body or subject line in the settings, it can contain special keywords representing variables such as the requester's name.

Need a class that will have methods that do all of this substitution, e.g.

emailContent.hydate(content, approvalRequest, reimbursementRequest)

[sbagg]

I need some clarification and examples on this? Like examples and outcomes this would be used in?

[spelkey-ucd]

// retrieved from settings table
content = `
Hi ${requesterFirstName},

Your travel, training, or professional development request has been successfully submitted. 
${nextApproverFullName ? `
It has been sent to ${nextApproverFullName} for approval.
` : ``}

You may cancel, resubmit, or view the status of this request at anytime by going to the following url: 
${approvalRequestUrl}
`

Then the email content class would look something like:

class EmaiContent {

constructor(approvalRequest, reimbursementRequest){
  this.approvalRequest = approvalRequest;
  this.reimbursementRequest = reimbursementRequest
}

_getContext(content){
  // extract variables from content string
  const variables = ['requesterFirstName', etc];

  // get values from approvalRequest/reimbursmentRequest
  const context = {};
  for (v of variables) {
    context[v] = this._getVariableFunction(v)
  }

 return context;
}

_getVariableFunction(variable){
// return method for getting data for variable
if (variable === 'requesterFirstName') return this._getRequesterFirstName;
// etc
return () => {return ''}
}

hydrate(content){
  const context = this._getContext(content);
  return this._evaluateTemplate(content, context);
}

_evaluateTemplate(template, context) {
    const templateFunction = new Function(...Object.keys(context), `return \`${template}\`;`);
    return templateFunction(...Object.values(context));
}
}

So then you would use the class to construct the email content you are sending:

emailContent = new EmaiContent(approvalRequest, reimbursementRequest);
emailSubject = emailContent.hydrate(subject);
emailBody = emailContent.hydrate(content);

emailService.send(recipients, emailSubject, emailBody);