Mockoon supports partial mocking of an API endpoints by forwarding the requests that does not match a declared route to the URL of your choice.
Open the Environment Settings by clicking on the cog in the upper right corner:
Enable proxy mode and enter the server URL to which you want to forward calls. A small shield icon should appear on the right of your environment name indicating that the proxy mode has been enabled:
All routes that have been defined will be intercepted by Mockoon, and any other request will be forwarded to the server defined in the proxy mode setting.
Proxy specific headers can also be added.
Proxy request headers will be automatically added to the request sent to the proxied server, while proxy response headers are added to the response received from the proxied server.
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