Heroku-Mailgun integration returns a 301 error on /msg. Config example:
forward('https://app.herokuapp.com/msg'); post('/msg', 'Inbox#recv'); class Inbox { def recv; head 200; end }
Any fixes?
Based on previous similar issues I encountered, the 301 error was triggered by a mismatch between the forwarded URL and the route settings on Heroku. I solved it by explicitly ensuring that the URL used in forwarding exactly matches the expected endpoint, including the case and any required trailing slashes. Additionally, verifying the SSL configuration helped me avoid any unintended redirection. Reviewing the request headers was also instrumental in pinpointing discrepancies in the redirection chain which ultimately led to a reliable solution.
I experienced a similar issue recently when setting up a Heroku and Mailgun integration. In my case, I eventually tracked down the problem by logging the complete redirect chain and paying close attention to reusable routing patterns. I discovered that subtle differences in URL syntax were the culprit – particularly mixing up the use of HTTP vs HTTPS and missing trailing slashes at crucial checkpoints. By aligning all configurations including any custom middleware that manipulated URLs, I was able to normalize the request flow. Reviewing detailed Heroku logs and comparing configurations in both Mailgun and my app was key in resolving the glitch.
i fixed a similar error by double checking my route setup, turns out the trailing slash on the mailgun endpoint was messing things up. removed the extra slash and verified the app config through heroku logs. hope that helps, sometimes the tiniest misconfig can cause the 301 issue
In my experience, the 301 error can sometimes stem from discrepancies between the configured domain on Heroku and the callback URL registered with Mailgun. I encountered a similar problem when using a custom Heroku domain that performed automatic HTTP to HTTPS redirection. The solution was to ensure that the endpoint specified in Mailgun matched the secure domain URL exactly. Additionally, verifying that any automated DNS or SSL redirections were properly managed helped resolve the issue. Utilizing Heroku’s debug logs provided further insight, ultimately leading to a consistent and correctly routed configuration.
After encountering similar issues, I found that when integrating Heroku with Mailgun, the redirection often occurred due to discrepancies in the application’s host settings. In my case, the problem was resolved by reviewing the app’s environment variables and ensuring that no secondary routing rules were interfering with the Mailgun endpoint. The solution involved verifying that the endpoint in Mailgun exactly matched the Heroku configuration, including updating any settings in the reverse proxy that may have introduced an unintended redirection. Persistently reviewing logs and rechecking configuration details ultimately led to a stable integration.