decoy 🦆
Summary
Run a server that returns mock responses for use in testing. New response configuration can be added dynamically so that test data needn't exist solely in static files. Responses use mustache templating with access to variables from JSON request bodies, URL parameters, and query string arguments.
Basic usage
Decoy can used as either a standalone executable or as a Haskell library.
Executable
The Decoy exectuable starts a mock server on the port specified by the
DECOY_PORT environment variable (defaults to 9000 if not specified). You can
also supply a path to a file containing rule specifications via the
DECOY_RULES_FILE environment variable.
Library
Haskell projects can take advantage of the API for manipulating running server instances without making network calls. See the library's haddock documentation for details on the available functionality.
Mock server usage
A Decoy server consists of a set of rules, each of which corresponds to an endpoint with a specific response and further conditions that must be met for the rule to be matched by a request. Rules can be supplied to the server by giving it the path to a static file containing JSON specifications for rules or by adding rules to server dynamically while it is running.
To add a rules dynamically, send a post request to the _add-rules endpoint
with an array of JSON specifications for the rules to be added as the request
body. The response will be a JSON array of the IDs assigned to those rules in
the order they were sent. For example, if the server is running on port 9000,
the request would be sent to http://localhost:9000/_add-rules. The JSON for
specifying a rule is outlined below. There is also an _add-rule endpoint for
adding a single rule rather than an array of rules which returns a single rule ID.
Rules can be removed from a server using the _remove-rules and _remove-rule
endpoints which take as the request body an array of rule IDs or a single rule
ID respectively.
The server can be reset to to its initial state by hitting the _reset endpoint.
Rule specification
The JSON schema for the rule specification object can be found here.