feat: mocks can be prioritised

Author: Raymond Ottun

docs/content/en/mocking.md

@@ -70,6 +70,9 @@ response:
 
 # Optional: defaults to unlimited
 limit: (number|unlimited). how many times this mock should be used. defaults to unlimited
+
+# Optional: defaults to 100
+priority: (number|unlimited). matching is ordered by priority (highest first) then creation (earliest first)
 ```
 
   </code-block>
@@ -103,7 +106,8 @@ limit: (number|unlimited). how many times this mock should be used. defaults to
         },
         "delay": "seconds to delay the response. defaults to 0"
     },
-    "limit": "(number|unlimited). how many times this mock should be used. defaults to unlimited"
+    "limit": "(number|unlimited). how many times this mock should be used. defaults to unlimited",
+    "priority": "matching is ordered by priority (highest first) then creation (earliest first)"
 }
 ```
 

src/engine/engine.test.ts

@@ -50,26 +50,26 @@ test('match simple method request', () => {
     });
 
     expect(matched).toMatchInlineSnapshot(`
-            Array [
-              Object {
-                "id": "exp1",
-                "limit": "unlimited",
-                "name": "sample1",
-                "request": Object {
-                  "headers": Object {},
-                  "path": "/todos",
-                },
-                "response": Object {
-                  "body": Array [
-                    Object {
-                      "id": 2,
-                      "text": "get request",
-                    },
-                  ],
+        Array [
+          Object {
+            "id": "exp1",
+            "limit": "unlimited",
+            "name": "sample1",
+            "request": Object {
+              "headers": Object {},
+              "path": "/todos",
+            },
+            "response": Object {
+              "body": Array [
+                Object {
+                  "id": 2,
+                  "text": "get request",
                 },
-              },
-            ]
-      `);
+              ],
+            },
+          },
+        ]
+    `);
 });
 
 test('match regex method request', () => {
@@ -220,29 +220,29 @@ test('match headers request', () => {
     });
 
     expect(matched).toMatchInlineSnapshot(`
-            Array [
-              Object {
-                "id": "exp1",
-                "limit": "unlimited",
-                "name": "sample1",
-                "request": Object {
-                  "headers": Object {
-                    "host": "example.com",
-                  },
-                  "method": "GET",
-                  "path": "/todos",
-                },
-                "response": Object {
-                  "body": Array [
-                    Object {
-                      "id": 2,
-                      "text": "get request",
-                    },
-                  ],
-                },
+        Array [
+          Object {
+            "id": "exp1",
+            "limit": "unlimited",
+            "name": "sample1",
+            "request": Object {
+              "headers": Object {
+                "host": "example.com",
               },
-            ]
-      `);
+              "method": "GET",
+              "path": "/todos",
+            },
+            "response": Object {
+              "body": Array [
+                Object {
+                  "id": 2,
+                  "text": "get request",
+                },
+              ],
+            },
+          },
+        ]
+    `);
 });
 
 test('match json body request', () => {
@@ -287,26 +287,26 @@ test('match json body request', () => {
     });
 
     expect(matched).toMatchInlineSnapshot(`
-            Array [
-              Object {
-                "id": "exp2",
-                "limit": "unlimited",
-                "name": "sample2",
-                "request": Object {
-                  "body": Object {
-                    "id": 3,
-                    "text": "new post",
-                  },
-                  "headers": Object {},
-                  "method": "POST",
-                  "path": "/todos",
-                },
-                "response": Object {
-                  "body": Array [],
-                },
+        Array [
+          Object {
+            "id": "exp2",
+            "limit": "unlimited",
+            "name": "sample2",
+            "request": Object {
+              "body": Object {
+                "id": 3,
+                "text": "new post",
               },
-            ]
-      `);
+              "headers": Object {},
+              "method": "POST",
+              "path": "/todos",
+            },
+            "response": Object {
+              "body": Array [],
+            },
+          },
+        ]
+    `);
 });
 
 test('match string body request', () => {
@@ -348,23 +348,23 @@ test('match string body request', () => {
     });
 
     expect(matched).toMatchInlineSnapshot(`
-            Array [
-              Object {
-                "id": "exp2",
-                "limit": "unlimited",
-                "name": "sample2",
-                "request": Object {
-                  "body": "[0-9]th todo",
-                  "headers": Object {},
-                  "method": "POST",
-                  "path": "/todos",
-                },
-                "response": Object {
-                  "body": Array [],
-                },
-              },
-            ]
-      `);
+        Array [
+          Object {
+            "id": "exp2",
+            "limit": "unlimited",
+            "name": "sample2",
+            "request": Object {
+              "body": "[0-9]th todo",
+              "headers": Object {},
+              "method": "POST",
+              "path": "/todos",
+            },
+            "response": Object {
+              "body": Array [],
+            },
+          },
+        ]
+    `);
 });
 
 test('mock: add results in error', () => {
@@ -384,18 +384,18 @@ test('mock: add', () => {
         });
     expect(add).not.toThrow();
     expect(engine.mocks).toMatchInlineSnapshot(`
-            Array [
-              Object {
-                "id": "new",
-                "limit": "unlimited",
-                "name": "base expectation",
-                "request": Object {
-                  "path": "/hello",
-                },
-                "response": Object {},
-              },
-            ]
-      `);
+        Array [
+          Object {
+            "id": "new",
+            "limit": "unlimited",
+            "name": "base expectation",
+            "request": Object {
+              "path": "/hello",
+            },
+            "response": Object {},
+          },
+        ]
+    `);
 });
 
 test('mock: remove', () => {

src/engine/engine.ts

@@ -99,11 +99,12 @@ export class Engine extends EventEmitter {
         return !!interfaces;
     };
 
-    private baseMock() {
+    private baseMock(): Mock {
         return {
             id: shortId(),
             name: 'Mock',
             limit: 'unlimited',
+            request: { path: '/hello' },
         };
     }
 
@@ -160,7 +161,11 @@ export class Engine extends EventEmitter {
                 return pastMatches < mock.limit;
             });
 
-        return matches;
+        return matches.sort((m1, m2) => {
+            const pr1 = m1.priority || 0;
+            const pr2 = m2.priority || 0;
+            return pr2 - pr1;
+        });
     }
 
     async proxy(req: ProxyRequest): Promise<Response> {

src/engine/priority.test.ts

@@ -0,0 +1,71 @@
+import { create } from '../engine';
+import { Mock, Request } from '../types';
+
+test('priority', async () => {
+    const mocks: Mock[] = [
+        {
+            id: 'exp1',
+            name: 'sample1',
+            request: {
+                path: '/todos',
+            },
+            response: {
+                body: 'No Priority set',
+            },
+            limit: 2,
+        },
+        {
+            id: 'exp2',
+            name: 'sample2',
+            request: {
+                path: '/todos',
+            },
+            response: {
+                body: 'Mock priority -1',
+            },
+            limit: 2,
+            priority: -1,
+        },
+        {
+            id: 'exp2',
+            name: 'sample2',
+            request: {
+                path: '/todos',
+            },
+            response: {
+                body: 'Mock priority 0',
+            },
+            limit: 2,
+            priority: 0,
+        },
+        {
+            id: 'exp2',
+            name: 'sample2',
+            request: {
+                path: '/todos',
+            },
+            response: {
+                body: 'Mock priority 1',
+            },
+            limit: 2,
+            priority: 1,
+        },
+    ];
+
+    const request: Request = {
+        path: '/todos',
+        method: 'GET',
+        headers: {},
+    };
+
+    const engine = create({ mocks, config: {} });
+
+    await engine.execute(request);
+    const lastMatch = await engine.execute(request);
+
+    expect(lastMatch.response).toMatchInlineSnapshot(`
+        Object {
+          "body": "Mock priority 1",
+        }
+    `);
+});

src/server/routes/mocks.test.ts

@@ -298,17 +298,17 @@ test('retrieve all mocks', async () => {
 
     expect(res.status).toBe(200);
     expect(res.body).toMatchInlineSnapshot(`
-            Array [
-              Object {
-                "id": "sample-mock",
-                "limit": "unlimited",
-                "name": "test mocks",
-                "request": Object {
-                  "method": "GET",
-                  "path": "/tasks",
-                },
-                "response": null,
-              },
-            ]
-      `);
+        Array [
+          Object {
+            "id": "sample-mock",
+            "limit": "unlimited",
+            "name": "test mocks",
+            "request": Object {
+              "method": "GET",
+              "path": "/tasks",
+            },
+            "response": null,
+          },
+        ]
+    `);
 });