Behave
The easiest and quickest way to mock HTTP endpoints for development and testing purposes
What is Behave?
Behave is an HTTP API mock server that can aid in rapid application development by mocking endpoints and configuring responses from configurations.
Behave can also act as a testing server to validate what requests made by system under test.
Quick Start
npx @sayjava/behave -b '[{"request": {"path":"/todo/[0-9]+"}, "response": {"body": "a simple todo"}}]'and test the endpoint
curl -X GET http://localhost:8080/todo/10Features
- Declarative request matching and response
- Regex based request matching (request path, headers and body matchers)
- Alternate and limit responses on same request
-
Templated based response, e.g
"Task is {{req.queryParams.name}}" - NodeJS HTTP/Express Middleware
- API Spec 3.0 & Swagger 2.0 complaint
- HTTP request validations
- Simulate response delays and network failures
- Serverless compatible
Examples
Here are some scenarios where Behave can be used to mock endpoints. Start the server on the default 8080 port
npx @sayjava/behaveRegex paths
npx @sayjava/behave -b '[
{
"name": "Match any task with id",
"request": { "path": "/tasks/[0-9]+" },
"response": {
"body": "found it"
}
}
]
'to match requests like these:
curl http://localhost:8080/tasks/2
curl http://localhost:8080/tasks/10Request headers
e.g {"user-a∫gent": "Chrome|Apple*"}
npx @sayjava/behave -b '[
{
"name": "Match requests coming from Apple devices or Chrome",
"request": {
"path": "/tasks/[0-9]+",
"headers": {
"user-agent": "Chrome|Apple*"
}
},
"response": {
"body": "Found on a mac or chrome"
}
}
]
'to match requests like:
curl http://localhost:8080/tasks/2 -H 'user-agent: Chrome'Templated response
HTTP response can be templated using Handlebars syntax
@sayava/behave -b `[
{
"request": {
"path": "/greet/:name",
"pathParams": {
"name": "[a-z]+"
}
},
"response": {
"body": "Hello {{req.pathParams.name}}"
}
}
]`to match requests and respond with the template:
curl http://localhost:8080/greet/janeand respond with Hello jane
Request body matchers
e.g {"user":"john_[a-z]+"}
@sayjava/behave -b '[{
"name": "Match requests with users with names like john_xxx",
"request": {
"path": "/tasks",
"method": "POST",
"body": {
"user": "john_[a-z]+"
}
},
"response": {
"statusCode": "201",
"body": "Task created by {{req.body.user}}"
}
}]
'to match requests like:
curl -X POST http://localhost:8080/tasks -H "content-type:application/json" -d '{ "user": "john_doe", "name": "pay up" }'Asserts received requests
Asserts that Behave has received a request with that path at least twice and at most 10 times
curl -X PUT http://localhost:8080/_/api/requests/assert -H "content-type:application/json" -d '[
{
"request": {
"path": "/todo/2",
"count": {
"atLeast": 2,
"atMost": 10
}
}
}
]'Asserts the sequence requests are received
Asserts that Behave has received a request with that path at least twice and at most 10 times
curl -X PUT http://localhost:8080/_/api/requests/sequence -H "content-type:application/json" -d '[
{
"request": {
"path": "/todo/2"
}
},
{
"request": {
"path": "/todosdss/20"
}
}
]'see the Behavior Guide
Programmatically Use cases (Express Middleware / NodeJS HTTP Middleware)
const express = require('express');
const { behaveHandler } = require('@sayjava/behave');
const app = express();
app.use(express.static(__dirname + '/views'));
// Existing route
app.get('/', (req, res) => res.render('index', { title: 'Hey', message: 'Hello there!' }));
// Mount the middleware on /api.
app.use('/api', behaveHandler({ config: { fromFile: 'api.json' } }));
app.listen(3000, () => console.info(`App started on 3000`));
