Is there is any open API for getting similar topic in discourse?

That seems like a private community so unauthenticated requests will not return any data. It works on Meta using https://meta.discourse.org/t/144806/2.json because the content is publicly viewable.

See Discourse REST API Documentation and Use the Discourse API ruby gem for more info on authenticating your requests with an api_key and api_username.

1 Like