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Blog
Showing 27 of 27.
Self-Hosted Sentry - force update "Allowed Domains" for JS project
My browser SDK stopped reporting. Every envelope came back 403:{"detail": "event submission rejected with_reason: Cors"}Server-side events kept arriving normally, the project's Allowed Domains was set to new-domain.com, and restarting Relay changed nothing.That combination means …
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Mail server blocklists
How DNSBLs work, what to do if you are listed, and why a checker sometimes cannot tell you.
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Email deliverability checklist
Reverse DNS, SPF, DKIM, DMARC, MTA-STS and blocklists, what each one actually does and the order to fix them in.
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MX records for mail delivery
What MX records do, how priorities work and why a second one is worth publishing.
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Reverse DNS for mail servers
PTR records, forward confirmed reverse DNS, and why you set them at your hosting provider.
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SPF records explained
Publishing SPF, choosing between ~all and -all, and the mistakes that switch it off completely.
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The SPF ten lookup limit
Why SPF silently stops working once the record needs more than ten DNS lookups, and how to get back under it.
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DKIM signing explained
How DKIM signatures work, what a selector is, and why a checker cannot always find your key.
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Rolling out a DMARC policy
From p=none to p=reject without blocking your own mail, and what the reports are actually for.
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MTA-STS and TLS reporting
Requiring TLS for inbound mail, and getting told when it fails.
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DNSSEC for mail
Why signing your zone matters when everything else you publish lives in DNS.
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STARTTLS and MX certificates
Encrypting mail in transit, and what a certificate name mismatch on an MX actually costs you.
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Docker Image for Django Application (Alpine Based)
Apline based images have a huge advantage by it’s final size but in most cases in the Python world if neotiates by Python dependencies which takes too long to build project packages and final …
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Django: Database Router for Multiple Databases
Using multiple database in the Django project you may face with situation when you need apply migrations for some app or model just to the some databse instead all of defined databases, or you …
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Django: Configure staticfiles directory for manage.py collectstatic
Starting new project it’s have no configured staticfiles directory configured by default, so it is not able you to use python manage.py collectstatic script to generate staticfiles bundle. It is small tip how to …
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Django: Pass Instance With Predefined Data to Form (CBV)
In case when you need to initialize form with already predefined details of the form instance, for example form that add comment to a post - you can predefine post_id in the form instance …
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Django get_success_url() to Previous Page
Easy way to redirect user on previous (original) page after form processing it is use HTTP_REFERER header, here an example how it’s may be implemented in the get_success_url() of the Django’s class based view.
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How to Pass Variable to the Template Class Based View
Simple example how to pass a variable to the class based view template context in Django. It also could be a queryset Then it can be looped in the template
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Raise Form Validation Error from form_valid() Method
In case if you need to make some validation steps directly in the view’s def form_valid() method and raise an ValidationError here an example Non field error example Field error
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Docker Image for Django Application (Debian Based)
Docker is most reliable and flexible way to distribute your Django applications, it able to include entire environment settings, dependencies and application files to deploy it to the server or any cloud provider.This post …
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Why Djnago Form Is Invalid? How to Print Errors?
Working with complex views that process multiple forms you can stuck on situation when some of forms didn’t validated but you have not see a reason for this, to debug this you can print …
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Choices Yes/No for Boolean Field in Django
Sometimes you need to represent boolean field of the Django model as dropdown list choices, like “Yes/No” instead default boolean field form widget - CheckboxInput. You can implement it like this. And ModelForm example
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Django Colored Output in PyCharm Run Configurations
Starting using PyCharm IDE for Django development you migt face with issue that default output of the PyCharm “Run Configuration” or “Services” panes colored by red regardless is it error or info line. You …
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Add Hash to Static Files Names in Django
It is very useful to append hash at the end of static files name such as js/css to prevent situation when website visitors after update still have old version of the file in browser …
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Use Environment Variables in Django - Efficient Way
If you stil not use environment variables to configure your Django application - dont wait, do it! I’ll tell you efficient way to use environment variables in the Django’s settings.py file which allows you …
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How to Use Multiple Databases in Django
Django ORM very well designed to use multiple relational databases (regardless engine) in single project. To start using two databases in Django project you need to configure connection to all of them in the …
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Set database tables prefix in Django
Sometimes when you using same database by different applications it is a good (or required) to separate tables between apps to avoid any conflicts. In this case you can find useful django-database-prefix library available …
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