API Simulator’s Blog


API Simulator 1.5 Release – HTTP/2 Support is Here!

December 30, 2019   We are excited to announce API Simulator version 1.5 and the support for the HTTP/2 (HTTP2) protocol!!! After three release candidates, the official support for HTTP/2 is here. To our knowledge, API Simulator is the first free API simulation tool to offer HTTP/2 in a stable release – not just some beta or a roadmap item – for running HTTP API simulations. Moreover, the support for HTTP/2 includes all three ways to start an HTTP/2 connection: TLS with ALPN, prior-knowledge, and upgrade from HTTP/1.1.   Below is a brief recap of the HTTP/2 support in API […]


API Simulator 1.4 Release

August 18, 2019   We are excited to announce API Simulator version 1.4! Here is the scoop: Added support for single configuration file for multiple simlets. It gives you a choice – place each simlet in separate directory as before or all simlets in a single configuration file. This can be very handy for smaller simulations. Shorter matcher configuration is now possible when the operation is `equals` for uriPath and uriPathPattern (example: “uriPath: /favicon.ico”). Added ability to use a placeholder or scriptlet to return dynamically the HTTP status code for a templated response. Before it was required to create a […]


API Simulator 1.3 Release

May 6, 2019   API Simulator version 1.3 is GA! As usual – with more goodies added to the toolbox. Here are the new features and major changes: Delay for latency simulation is now non-blocking – elevating to new levels performance testing of APIs with simulated latency! No more naive blocking of the execution thread. Added normal and lognormal distributions of delay values for more real lifelike latency simulations. Added Access Logging. When enabled, it captures timestamp, remote and local addresses, the request method and URI, simlet name, delay applied, and internal elapsed time from the time of receiving the […]


How to Connect JProfiler to a JVM Running in Kubernetes Pod

Running a JVM in Kubernetes Pod somewhat complicates things when it comes to connecting to it from an external profiler tool. Below is an example of how to accomplish just that with one such tool – JProfiler. A definitely not recommended approach is to “bake” JProfiler in the application’s image, which leads to tight coupling and larger application image. A better way is to use an Init Container. A Pod can have one or more Init Containers. For the most part, they are like regular Containers and have the property that once their execution completes successfully they are terminated; only […]


API Simulator 1.2 Release

January 15, 2019   We are pleased to announce the release of API Simulator version 1.2. Here is what is new and what changed: Introduced a new built-in Request Object – “_request” – that can be used in templates to get access to parts of the HTTP request and use them in rendering the response. The Request Object compliments the existing support for parameters from HTTP request components – use whichever approach suits your style. Update to the YAML DSL: the “matchers” top-level element has been deprecated and replaced by “request”. This makes for an even easier to read configuration […]