如何使用 AWS SES sendEmail API 发送 html 邮件

Question

I'm trying to send HTML email via AWS SES using sendEmail API.

It works perfect if I remove the content type header.

#!/bin/bash

TO="a@b.com"
FROM="b@a.com"
SUBJECT="test subject"
MESSAGE="<B>Test Message</B><br /> test message"

date="$(date -R)"
access_key="<aws key>"
priv_key="secret key>"
signature="$(echo -n "$date" | openssl dgst -sha256 -hmac "$priv_key" -binary | base64 -w 0)"
auth_header="X-Amzn-Authorization: AWS3-HTTPS AWSAccessKeyId=$access_key, Algorithm=HmacSHA256, Signature=$signature"
endpoint="https://email.us-west-2.amazonaws.com/"
content_type="Content-Type: text/html"
mime_version="MIME-Version: 1.0"
action="Action=SendEmail"
source="Source=$FROM"
to="Destination.ToAddresses.member.1=$TO"
subject="Message.Subject.Data=$SUBJECT"
message="Message.Body.Text.Data=$MESSAGE"

curl -v -X POST -H "$auth_header" -H "Date: $date" -H "$content_type" -H "$mime_version" -H "Content-Length: 50" --data-urlencode "$message" --data-urlencode "$to" --data-urlencode "$source" --data-urlencode "$action" --data-urlencode "$subject"  "$endpoint"

But with the content type set to text/html I'm getting this error

<AccessDeniedException>
<Message>Unable to determine service/operation name to be authorized</Message> 
</AccessDeniedException>

Please help.

Answer 1

It works perfect if I remove the content type header.

Yes, because your use of the Content-Type: text/html header here is wrong.

The Content-Type: header of the HTTP request has nothing to do with the mail body -- it's the content type of the API request. The correct value is application/x-www-form-urlencoded -- notice that this is how you are encoding the POST body with --data-urlencode ... which is correct.

So, when you don't set it manually, either curl is setting it for you, or the API is cutting you some slack and assuming it's the expected encoding, since you didn't specify otherwise... but specify the wrong encoding and the API rejects the content, since it doesn't make sense to the receiving system.

The way to tell the SES API that you're sending an HTML body is to change this...

message="Message.Body.Text.Data=$MESSAGE"

...to this...

message="Message.Body.Html.Data=$MESSAGE"

http://docs.aws.amazon.com/ses/latest/APIReference/API_Body.html

You can also send both bodies together, plain text and HTML, by including both. That way, HTML multipart/alternative-capable mail readers will render the HTML body, other more primitive mail readers will render the text body.