I have set up a custom email sender function that currently just decrypts the code (if present) and logs the event.
I can see in the logs that the lambda is correctly triggered for the other trigger source types such as CustomEmailSender_AdminCreateUser when I run the aws cognito-idp admin-create-user CLI command, and the CustomEmailSender_ForgotPassword when I submit the Forgot Password form on the Hosted UI. However, I do not see any logs when user attributes are updated. I've tested with both the admin-update-user-attributes and the update-user-attributes commands, as well as in the AWS console.
When is the email with the CustomEmailSender_UpdateUserAttribute trigger source sent? Is there a configuration on my user pool or client that I am missing?
According to Cognito documentation on Custom message Lambda trigger sources:
CustomMessage_UpdateUserAttribute | Custom message – When a user's email or phone number is changed, this trigger sends a verification code automatically to the user. Cannot be used for other attributes.
So it only triggers with changes to the email or phone number fields, in order to verify them.
I'm using Firebase auth to control access to my app and it's been working great and was easy to implement. Now that I'm bringing real testers on, I've got a question.
When a user registers, I'm forcing email verification and that all works fine. I've even found how to somewhat customize the email that user receives asking them to verify their address. However, when the user clicks that link, they get a very generic message:
Your email has been verified
You can now sign in with your new account
Is there any way to customize this? I don't want to do anything particularly fancy - just a more helpful message and maybe a link to return to the app.
Thoughts?
If you mean the web page that they get to when they click the link, there is no way to customize the existing page. But you can create your own page, and host it (for example on Firebase Hosting). For full documentation on this process, see the documentation on creating a custom email action handler.
I send the document to DocuSign in draft status. Then user(contract owner) logs into DocuSign, adds additional signers and tags then sends the document for signing.
Is it possible to get the original unsigned document(pdf) that was sent after the document is completed via the API?
The reason I need the original document is to make sure that the user(contract owner) has not changed/modified the document in DocuSign.
I want to make sure the signed document is exactly the one I sent via API.
DocuSign does not have granular permissions to block changes to the documents when the Envelope is in draft status.
Re: Is there a way to get back the original unsigned document that was sent to DocuSign after it is signed/completed?
Answer: unfortunately, no. As soon as original documents are uploaded to DocuSign, they are converted into a "flat" (no logic) PDF. The original document is then discarded.
As a workaround, you could programmatically create a template, then create an envelope from the template. Then the user could tag the document without the ability to change the document. See use case 8, creating a template programmatically for code examples. These are on the eg-03 series of examples. Eg, the PHP code example.
Or better, update your application to tag the documents for the user.
We are investigating the idea of enabling the documents in an envelope to be locked. Please ask your DocuSign business or support contact to add your company information to DocuSign internal issue number SMPI-236.
Can I edit a template or check a box or do something which allows the Return Request notification which is sent to the email specified in the Store Profile to have a reply-to address of the customer that submits the request?
This way it'll look like it's coming from the user and I can reply to it normally.
You can't unless you use a custom form rather than the builtin forms. You can build it using javascript, a prebuilt resource, or an app from the BC app store.
I'm trying to develop a REST API web service. I have a question about how to handle user activation email. Currently, the API service handles email sending.
Here is the flow I have at the moment:
User registers via the client application
Client application POSTs to API service
API service validates and adds the user to the database
API service sends the User an activation link
User clicks on the activation link, which will take them to the client application activation page
Client application activation page POSTs to API service
Done
Here is where I currently see the issue:
Because the API service is currently sending the email, the client application does not have control over the look and feel of the email. And there may be URLs in the email that should point to the client application.
Another option is instead of the API service sending the activation email, it will return the activation key to the client application. The client application will then be able to send the activation email to the user.
Two issues I see with this strategy:
Security, as the activation key is now exposed to the client application.
Not DRY, as each client could be responsible for email sending.
What do you think is best way to handle this?
I would like to allow the client application to customize their email, as well as include client-specific URLs (activation page).
TL;DR
Create a small service for developers to create templates, let them declare which template they want to use when POSTing to your activation API
Summary of the problem:
e-mail needs to look different for every client app
sending mail should be implemented once
solution should be secure
There is no need for the e-mail to look different every time. So there's no need to send the e-mail format with the POST request.
Instead one of the following can be done:
1 Create a separate API endpoint to define templates and let the client app choose one of them when POSTing the request for activation.
This is not exactly secure, at least poses a challenge to make it safe if you want to accept HTML from the client apps.
Recommended solution:
2 Create a tool for developers (in the same website where they get their API key) that accepts templates and aids creating them. Client app can choose one of them when POSTing the request for activation. Fragment of the request body being something like:
...
"template": "foobar-app",
"fields": {
"title": "Welcome to foobar app",
"username": "jim78"
}
...
No HTML in the fields allowed.
This lets you have pre-defined templates prepared by the developer that can be used by your e-mail sending service and no bug in client app can cause the e-mail to become unsafe. Also, you get a place where the templates can be worked on and tested. (the developer can send them to himself to debug - making e-mail templates is horrible, belive me)
You'll be able to support your developers/clients better in the future and prepare a set of working templates tested in multiple mail clients.
A point about security and trust. Typically you send an activation email that contains a url link that has the activation code. The purpose of the email is to validate that the email is valid and that the user has access to that email. The only way the user could have received the verification link is through the email.
If you pass back the activation link to the client then anyone who has access to your API has access to the activation code. If they have access to the link they can bypass the verification process. This is really easy if you have a web app, as they just need to drop into the browser developer mode to see the link. If you have a fat client then they could snoop the network if you are not using encryption like https. They could also, if they were dedicated, decompile your binary (this is why you d not store keys in your binaries).
A backend should never trust a client to implement a security procedure because it never knows when it has been compromised. The safe and correct way is to do the activation email on the server side.
Another way to look at this, is that it is similar to the client saying "yes the user is authenticated so give me all the data"
As for the templates there are plenty of good answers above. I would suggest having a catalog of templates and a list of arguments that can be replaced.
So the way I achieved this in my opinion is quite a nice way. So I took the methodology of how JSON Web tokens work and applied it to my activation links. I'll explain how it works:
I have 2 web servers, one which handles the REST API, and one which handles the spa.
So the user registers, and the request is sent to the API. The response is then returned to the SPA at which point if successful sends a request to the SPA Backend which signs a token with the user's credentials, the purpose of the token (which is this case is to verify the email address) and it's expiry date.
This token is sent to the user's email address, however on the REST server there is a receiving route that will decode the token and if valid, verifies the email address.
This does mean that technically only 1st party clients can authenticate the email address as they are the only ones that can know your cipher secret. If your secret was freely handed out, then the problem would occur that anyone could verify their email address.
I hope this helps!
EDIT: another way would be to pass a template built in handlebars or something that swaps out variables for actual values. Then have the REST api render it, and email it. (This is probably the best way imo haha)
Your API could have an IEmailBodyFormatter object that is passed as a parameter to your API call....
I'd extend step 2 with additional post-data sent to the server:
"mail":{
"placeholder":"someStringChoosenByClientWhichWillBeReplaceByActivationCode",
"subject":"Hey there, please activate",
"ishtml":false,
"body":"SSdtIHRyeWluZyB0byBkZXZlbG9wIGEgUkVTVCBBUEkgd2ViIHNlcnZpY2UuIEkgaGF2ZSBhIHF1ZXN0aW9uIGFib3V0IGhvdyB0byBoYW5kbGUgdXNlciBhY3RpdmF0aW9uIGVtYWlsLiBDdXJyZW50bHksIHRoZSBBUEkgc2VydmljZSBoYW5kbGVzIGVtYWlsIHNlbmRpbmcu"
"attachments":[
{
"content-type":"image/png",
"filename":"inline_logo.png",
"content":"base64_data_of_image"
}
]
}
This would allow the client full control over sent message, but the activation procedure (mail generation & delivery) is still handled by the service.
Everything except the activation key can be generated for every user by the client (e.g. using "Hello XYZ" as Subject).
I'm not sure whether it's an good idea to allow html-Mails ("ishtml":false,), this depends on your application and the amount of time you want to spent implementing this.
Allow the client to manage their own email template(s). When they post a new user registration, allow them to specify which template to use. Then your application is sending the email message, but clients can control what it looks like.
POST /email-templates
{
"subject": "Complete Your Registration",
"body": "<html>Follow this link to complete your registration: {activationLink}. It is valid for 45 minutes.</html>"
}
POST /registration-requests
{
"name": "John Q. Public",
"emailTemplate": "/email-templates/45"
}
I think the proper way is to expose the activation key for the client to do whatever it wants with.
You could also add another endpoint to send the activation key for the user.
Returns user. (with the url like User/{userid} and other resources url like User/{userid}/ActivationKey)
User (POST)
This can returns the current user and other resources like Email, Activate, etc.
For info about the key (like dates, expiration, etc)
User/{userid}/ActivationKey
from there you can extend it as long as you want with :
Preview activation email:
User/{userid}/ActivationKey/Email (GET)
Update activation email with template, smtp server, etc of the email. :
User/{userid}/ActivationKey/Email (PUT)
Create (and send) activation email, possible with date to send or other send options (text-html versions, etc) :
User/{userid}/ActivationKey/Email (POST)
You could possibly list all email sent and preview them in another endpoint if necessary.
User/{userid}/Emails (GET)
User/{userid}/Emails/{emailid} (GET)
I join nauktur on the idea of letting the client send you a template of his email. (And +1 for talking about a way to test, because I agree on the awfulness of mail "development").
But why so complicated ? Client apps mean developers, so why not let them give them your default template (with HTML), let them play around if they want to, and send you back the version they prefer ?
It's not a lot of work for you (just a new field in the client table and a new route), and it gives them a lot of options.
Here is a basic example where we'll be exposing some parameters so that they can play around with the HTML without even having to know them :
app.name
app.description
activation_code
user.* registering info
Basic template
{
title: "Your activation code for %{app.name}",
body: "<p>Hi, you've been registered on %{app.name}.
<p>%{app.description}</p>
<p>Follow this link to confirm your inscription."
}
Register new template
Then the client says : "I prefer to have a more simple mail, but I want his name in it !".
[PUT] /api/email/templates/client_id
{
title: "Your activation code",
body: "<p>Hi %{user.fullname}, Follow this link to confirm your inscription."
}
And here you go. Let them play with HTML, it allows way more personalization.
There's no harm in it except for their image on their clients if they mess up, but they're their clients.
Security issues
It was pointed out that attackers could get access to the token of the client app could inject malicious content in the template. First of all, the risk is already so high if the token leaks, that this is the last of your concerns. Still, if you're scared of this, disallowing img tags and making the content of a tags match the href attribute should solve your issue.