(Chilkat2-Python) Using Replace Patterns in Email

See more Email Object Examples

Demonstrates how to use the replace patterns (mail-merge) feature in Chilkat MailMan.

Chilkat2 Python Downloads

install with pip
pip3 install chilkat2
or download... Python Module for Windows, Linux, Alpine Linux, MacOS, Solaris

import sys
import chilkat2

# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

# ---------------------------------------------------------------------
# Create an email template for sending.
emailTemplate = chilkat2.Email()

# We're going to replace "FIRST_NAME" with an actual name.
# We arbitrarily chose "FIRST_NAME".  We can choose anything, such as "CUSTOMER_NAME" or "THE_RECIPIENT_NAME"...
emailTemplate.Subject = "Hello FIRST_NAME,"

emailTemplate.From = "john@example.com"
emailTemplate.AddTo("FIRST_NAME","RECIPIENT_EMAIL")

emailTemplate.SetHtmlBody("<html><body><h2>Hello FIRST_NAME,</h2><p>Your order for PRODUCT_NAME has been shipped.</p></body></html>")

# If the email is saved to a file, we can see what it contains:
emailTemplate.SaveEml("qa_output/emailTemplate.eml")

# For example:

# MIME-Version: 1.0
# Date: Tue, 26 Apr 2022 07:10:52 -0500
# Message-ID: <715CF231A9F07B0B9FDB073518CD94138D791866@XYZ>
# Content-Type: text/html; charset=us-ascii
# Content-Transfer-Encoding: 7bit
# X-Priority: 3 (Normal)
# Subject: Hello FIRST_NAME,
# From: john@example.com
# CKX-Bounce-Address: john@example.com
# To: FIRST_NAME <RECIPIENT_EMAIL>
# 
# <html><body><h2>Hello FIRST_NAME,</h2><p>Your order for PRODUCT_NAME has been shipped.</p></body></html>

# Note: Ignore the CKX-Bounce-Address header.  It is automatically removed by Chilkat prior to sending.
# All "CKX-" headers are automatically removed prior to sending.

# ---------------------------------------------------------------------
# Demonstrate replace patterns by setting and then rendering to MIME.

mailman = chilkat2.MailMan()

emailTemplate.SetReplacePattern("FIRST_NAME","Elon")
emailTemplate.SetReplacePattern("RECIPIENT_EMAIL","elon.musk@example.com")
emailTemplate.SetReplacePattern("PRODUCT_NAME","Twitter Corporation")

# Render to MIME to see what we get.
# Note: When the MailMan sends an email, it renders the email to MIME and then sends.
# The rendering process is to do replacements, or possibly sign, encrypt, etc.
# When MailMan.SendEmail is called, internally the email is rendered, and the rendered email is sent.
# The equivalent to MailMan.Send email is to call email.RenderToMime followed by MailMan.SendMime.
mime = mailman.RenderToMime(emailTemplate)
print(mime)

# This is the rendered MIME:

# MIME-Version: 1.0
# Date: Tue, 26 Apr 2022 07:25:49 -0500
# Message-ID: <750582BCDC891C67B48CEE2293C08B902C3891E9@XYZ>
# Content-Type: text/html; charset=us-ascii
# Content-Transfer-Encoding: 7bit
# X-Priority: 3 (Normal)
# Subject: Hello Elon,
# From: john@example.com
# To: Elon <elon.musk@example.com>
# 
# <html><body><h2>Hello Elon,</h2><p>Your order for Twitter Corporation has been shipped.</p></body></html>

# Note: When rendering, the Date and Message-ID headers are automatically regenerated.

# ---------------------------------------------------------------------
# An application can see what replacement patterns it previously set by calling SetReplacePattern multiple times.
count = emailTemplate.NumReplacePatterns
print("Number of replace patterns: " + str(count))

i = 0
while i < count :
    # Note: The GetReplaceString method was found to not be working correctly.  It was returning the same value as GetReplacePattern.
    # It is fixed in Chilkat v9.5.0.91
    print(emailTemplate.GetReplacePattern(i) + ": " + emailTemplate.GetReplaceString(i))
    i = i + 1

# Or lookup a replacement pattern by name:
name = "FIRST_NAME"
print(name + " = " + emailTemplate.GetReplaceString2(name))

# Sample output:

# Number of replace patterns: 3
# FIRST_NAME: Elon
# RECIPIENT_EMAIL: elon.musk@example.com
# PRODUCT_NAME: Twitter Corporation
# FIRST_NAME = Elon

# ---------------------------------------------------------------------
# Finally... demonstrate sending emails using the replacement patterns.
# 

# Set our mail server settings..
mailman.SmtpHost = "smtp.mail.us-west-2.awsapps.com"
mailman.SmtpSsl = True
mailman.SmtpPort = 465

mailman.SmtpUsername = "john@example.com"
mailman.SmtpPassword = "the_password"

# Imagine we have data in JSON format, and we wish to send the templated email to each recipient...
# 

# {
# 	"mail_merge" : [
# 		{
# 			"to": "mary@example.com",
# 			"name": "Mary",
# 			"product": "Widget 1" 
# 		},
# 		{
# 			"to": "robert@example.com",
# 			"name": "Robert",
# 			"product": "Widget 2"
# 		}	
# 		...
# 	]
# }

json = chilkat2.JsonObject()
success = json.LoadFile("qa_data/json/mail_merge.json")
if (success == False):
    print(json.LastErrorText)
    sys.exit()

i = 0
count = json.SizeOfArray("mail_merge")
while i < count :
    json.I = i
    emailAddr = json.StringOf("mail_merge[i].to")
    firstName = json.StringOf("mail_merge[i].name")
    product = json.StringOf("mail_merge[i].product")

    emailTemplate.SetReplacePattern("FIRST_NAME",firstName)
    emailTemplate.SetReplacePattern("RECIPIENT_EMAIL",emailAddr)
    emailTemplate.SetReplacePattern("PRODUCT_NAME",product)

    success = mailman.SendEmail(emailTemplate)
    if (success == False):
        print(mailman.LastErrorText)
        sys.exit()

    print("Send email to " + emailAddr)

    i = i + 1

print("Success.")