How to add unsubscribe header?

[addsimm]

Issue Summary

I'm trying to add an unsubscribe header and the docs are not very clear, then tech support told me to ask here ...

Here is my code from Django 3.9, which is working fine:

    from sendgrid import SendGridAPIClient
    from sendgrid.helpers.mail import Mail, To

    for lead_page in lead_paginator.page_range:
        sents = sents + '----------------lead_page: ' + str(lead_page)
        to_emails = []
        for lead in lead_paginator.page(lead_page).object_list:
            pixel_url = 'e=' + lead.lead_email + '&s=' + e_archive.subject_slug

            one_to_email = To(email=lead.lead_email,
                    name=lead.first_name,
                    substitutions={
                            '<< first_name >>': first,
                            '<< pixel_url >>': pixel_url
                    },
                    subject=e_archive.subject)

            to_emails.append(one_to_email)

        message = Mail(
                from_email=('xxxxx@xxxxx.com', 'xxxxx'),
                to_emails=to_emails,
                subject=e_archive.subject,
                html_content=e_html,
                is_multiple=True)

So where do I add an unsubscribe header based off of the pixel_url, so its personalized; something like:

  "headers": {
    "List-Unsubscribe": "<https://xxxxx.com/download/?<< pixel_url >>&p=unsubscribe>"
  }

[childish-sambino]

Does this article help to achieve what you're looking to implement?

https://dgorski.medium.com/setup-unsubscribe-with-sendgrid-api-dynamic-templates-3b942d325d3d

[rakatyal]

Closing due to lack of activity.

[addsimm]

Why did you close this contrary to an ongoing discussion?

…

Sent from my iPhone

On Apr 12, 2022, at 8:06 AM, Raghav Katyal ***@***.***> wrote:  Closed #1045. — Reply to this email directly, view it on GitHub, or unsubscribe. You are receiving this because you authored the thread.

[addsimm]

There is activity please and it hasn’t been resolved, please don’t close this

…

Sent from my iPhone

On Apr 12, 2022, at 8:33 AM, Adam Simon ***@***.***> wrote:  Why did you close this contrary to an ongoing discussion? Sent from my iPhone >> On Apr 12, 2022, at 8:06 AM, Raghav Katyal ***@***.***> wrote: >> >  > Closed #1045. > > — > Reply to this email directly, view it on GitHub, or unsubscribe. > You are receiving this because you authored the thread.

[rakatyal]

Reopening due to user request. Please let us know how we can further help you.

[addsimm]

You can give me the time we agreed to try to find and implement the putative GitHub response

…

Sent from my iPhone

On Apr 12, 2022, at 8:59 AM, Raghav Katyal ***@***.***> wrote:  Reopening due to user request. Please let us know how we can further help you. — Reply to this email directly, view it on GitHub, or unsubscribe. You are receiving this because you authored the thread.

[addsimm]

Still waiting on a response, the article cited is too generic to be useful

[tparkertwilio]

Hello,

I hope you are doing well today.

I read through the primary issue for this query of wanting to add a substitution value into a list-unsubscribe header for the mail send API. I tested this using the following code (which does allow the header to be added of "X-Test-Header", but the value is not substituted):

{
"personalizations": [{
"to": [{
"email": "sendgridtesting@gmail.com"
}],
"subject": "Testing Header Substitution",
"substitutions": {
"-Test-": "12345"
}
}
],
"from": {
"email": "from@example.net"
},
"headers": {
"X-Test-Header": "-Test-"
},
"content": [
{
"type": "text/html",
"value": "<title></title>Here is HTML text."
}
]
}

The above code is similar to the published mail send API for Python here: https://github.com/sendgrid/sendgrid-python/blob/main/examples/mail/mail.py#L95-L131 I added the test header and substitutions. Note that I also tried nesting the header directly in the personalization block of the code and the result was the same (substitution does not occur).

I know that substitutions will not work for every parameter of a mail payload (regardless of if Python VS C#, etc. are used). I recognize that exceptions could be made more clear as to give you understanding for what is and is not possible when using the API. You can include a list-unsubscribe header, for instance; however, usage of the substitution does not work in these headers from my testing and looking over other support articles and issues historically (i.e. looking for other similar cases, not a specific article or issue in which it is directly addressed).

In the interest of helping achieve a similar result, please note that you can add substitutions into HTML and subjects. Because the header is not being replaced, consider making the substitution with a custom unsubscribe link in the HTML of the email instead if it suits as a workaround:

{
"personalizations": [{
"to": [{
"email": "sendgridtesting@gmail.com"
}],
"subject": "Testing Header Substitution",
"substitutions": {
"-Test-": "12345"
}
}
],
"from": {
"email": "from@example.net"
},
"content": [
{
"type": "text/html",
"value": "<title></title>Here is some plain text.<a href="https://www.google.com?unsub_link=-Test-">Here is a link!"
}
]
}

I copied this in the existing support ticket as well for visibility. As it relates to inconsistencies or lack of documentation for how to use the API, I would open a separate issue aside from the one that exists for the header substitution using the mail send API.

Thank you,