Merging/Combine ESP Options get lost/overwritten

[mounirmesselmeni]

Reporting an error? It's helpful to know:

• Anymail version: 10.1
• ESP (Mailgun, SendGrid, etc.): SparkPost // But irrelevant
• Your ANYMAIL settings (change secrets to "redacted") {"SPARKPOST_SEND_DEFAULTS": {"transactional": True}}
• Versions of Django, requests, python: Django 4.2, Python 3.11
• Exact error message and/or stack trace: No Error
• Any other relevant code and settings (e.g., for problems sending, your code that sends the message)

The documentation says that when using ESP extra those options will be merged if defined in message.esp_extra, but in reality those options get overriden, if I pass in message.esp_extra for example the pool_name, the default transactional will be missing.

This is because inside anymail's combine function, the python dict.update check only for first level.

In other words:

dict1 = {"options": {"transactional": True}}
dict2 = {"options": {"pool_name": "custom_poolname"}}

dict1.update(dict2)
# will be -> {"options": {"pool_name": "custom_poolname"}}

this is what is done in the combine function https://github.com/anymail/django-anymail/blob/main/anymail/utils.py#L50

[medmunds]

@mounirmesselmeni thanks for the bug report. We should use a deep merge for esp_extra. (This will only affect ESPs that use nested data structures in their payloads: Sparkpost, Mandrill, maybe a few others I'm forgetting.)

[medmunds]

Fix released in Anymail 10.2