Performance

RapiDoc is fast enough to parse and render OpenAPI spec, but if used in a wrong manner it may lag a bit when dealing with large specs

How Large is a Large Spec ?

There are many factors thats responsible to call a spec a large spec, such as

• size
• number of schemas and operations defined
• number of references to a schema etc

There isn't any clear way to declare a spec large. For instance a large sized spec ( ~ 6 mb) containing lot of description text is not considered large for parsing and rendering on the other hand a medium sized spec which has containing many operations/paths all of which are referring to a single schema can lead to a very large output due to the repeated use of schema.

Performance Tips

Below are some general tips that you can apply when you are dealing with slow rendering

• If you are using version 2 of OpenAPI spec (swagger 2.0), then pre convert it to OpenAPI 3.x. When you provide a swagger 2.0 spec to RapiDoc, it attempts to convert it into OpenAPI 3.x which is a very high resource consuming operation.
• Use render-style as "view" or "focused" these rendering styles are very fast as they use lazy rendering of the views

A large spec is used for the below performance test cases
Swagger 2.0 (CAUTION !!! - browser may become unresponsive ) Most of the time is taken by swagger 2 to OpenAPI conversion
OpenAPI 3.0 - Read Mode (okay performance) The above spec pre-converted to OpenAPI 3 - read-mode renders everything in one large page, resulting into very large DOM, the user interactions like expand collapse are not much snappier
OpenAPI 3.0 - View Mode (fast) initial load is quick and user interaction is snappy, DOM is a bit larger than focused mode but very small compared to read mode
OpenAPI 3.0 - Focused Mode (fastest) loads only the section that user is viewing, resulting into a small DOM footprint and snappier interactions