AssertionError [ERR_ASSERTION]: Model is not provided
at router.param (/home/scrapbook/tutorial/app.js:15:3)
at middleware (/home/scrapbook/tutorial/node_modules/koa-router/lib/layer.js:181:15)
at dispatch (/home/scrapbook/tutorial/node_modules/koa-router/node_modules/koa-compose/index.js:4
4:32)
at next (/home/scrapbook/tutorial/node_modules/koa-router/node_modules/koa-compose/index.js:45:18
)
at /home/scrapbook/tutorial/node_modules/koa-router/lib/router.js:346:16
at dispatch (/home/scrapbook/tutorial/node_modules/koa-router/node_modules/koa-compose/index.js:4
4:32)
at /home/scrapbook/tutorial/node_modules/koa-router/node_modules/koa-compose/index.js:36:12
at dispatch (/home/scrapbook/tutorial/node_modules/koa-router/lib/router.js:351:31)
at dispatch (/home/scrapbook/tutorial/node_modules/koa-compose/index.js:42:32)
at /home/scrapbook/tutorial/node_modules/koa-compose/index.js:34:12
Error: expected 200 "OK", got 500 "Internal Server Error"
at Test._assertStatus (/home/scrapbook/tutorial/node_modules/supertest/lib/test.js:268:12)
at Test._assertFunction (/home/scrapbook/tutorial/node_modules/supertest/lib/test.js:283:11)
at Test.assert (/home/scrapbook/tutorial/node_modules/supertest/lib/test.js:173:18)
at Server.localAssert (/home/scrapbook/tutorial/node_modules/supertest/lib/test.js:131:12)
at Object.onceWrapper (events.js:273:13)
at Server.emit (events.js:182:13)
at emitCloseNT (net.js:1668:8)
at process._tickCallback (internal/process/next_tick.js:63:19)