Prism is a set of packages for API mocking and contract testing with OpenAPI v2 (formerly known as Swagger) and OpenAPI v3.x.
Note: This branch refers to Prism 3.x, which is the current version most likely you will use. If you're looking for the 2.x version, look at the
Prism requires NodeJS >= 12 to properly work.
npm install -g @stoplight/prism-cli # OR yarn global add @stoplight/prism-cli
For more installation options, see our installation documentation.
prism mock https://raw.githack.com/OAI/OpenAPI-Specification/master/examples/v3.0/petstore-expanded.yaml
prism proxy examples/petstore.oas2.yaml https://petstore.swagger.io/v2
Cannot access mock server when using Docker?
Prism uses localhost by default, which usually means 127.0.0.1. When using docker the mock server will
be unreachable outside of the container unless you run the mock command with
Why am I getting 404 errors when I include my basePath?
OpenAPI v2.0 had a concept called "basePath", which was essentially part of the HTTP path the stuff
after host name and protocol, and before query string. Unlike the paths in your
paths object, this
basePath was applied to every single URL, so Prism v2.x used to do the same. In OpenAPI v3.0 they
merged the basePath concept in with the server.url, and Prism v3 has done the same.
We treat OAS2
host + basePath the same as OAS3
server.url, so we do not require them to go in
the URL. If you have a base path of
api/v1 and your path is defined as
hello, then a request to
http://localhost:4010/hello would work, but
http://localhost:4010/api/v1/hello will fail. This
confuses some, but the other way was confusing to others. Check the default output of Prism CLI to
see what URLs you have available.
Is there a hosted version of Prism?
Yes, hosted mocking is available as part of Stoplight Platform. Learn More
If you're using Prism for an interesting use case, contact us for a case study. We'll add it to a list here. Spread the goodness 🎉
Prism is built on top of lots of excellent packages, and here are a few we'd like to say a special thanks to.
Check these projects out!