feat(path): add method to transform a usual "route" into a path for t…

…he db

With this feature you can easily transform `/user/123` into a path to get the data in node-json-db.

src/JsonDB.ts

@@ -432,4 +432,43 @@ export class JsonDB {
             throw new DatabaseError("Can't save the database", 2, err)
         }
     }
+
+
+    /**
+     * Convert a router style path to a normal path
+     * By default propertyName to search is "id"
+     * @param path router based path to a correct base path
+     * @param propertyName name of the property to look for searchValue
+     */
+    public async fromPath(path: string, propertyName:string = 'id' ): Promise<string> {
+
+        const [,...pathToQuery] = path.split("/")
+
+        const pathObject = pathToQuery.reduce((prev, curr, indexPath) => {
+            const isKey = indexPath % 2 === 0
+            if (isKey) {
+                prev[`${curr}`] = ''
+            } else {
+                const keys = Object.keys(prev)
+                prev[`${keys[keys.length - 1]}`] = `${curr}`
+            }
+            return prev
+        }, {} as {[key: string]:string})
+
+        let normalPath: string[] = []
+
+        for await (const pathKey of Object.keys(pathObject)) {
+            normalPath.push(`/${pathKey}`)
+
+            const pathValue = pathObject[pathKey]
+            try {
+                const pathIndex = await this.getIndex(normalPath.join(""), pathValue, propertyName)
+                normalPath.push(`[${pathIndex}]`)
+            } catch (error) {
+                throw new DataError(`DataPath: ${normalPath.join("")}/${pathValue} not found.`, 13, error)
+            }
+        }
+
+        return normalPath.join("")
+    }
 }

test/04-array-utils.test.ts

@@ -212,6 +212,88 @@ describe('Array Utils', () => {
             expect(nestedArrayIndicies[1]).toEqual('2')
         })
     })
+    describe('To router path style to normal path', () => {
+        test('should convert a router style path to a normal path', async () => {
+            const recipe_1 = {
+                id: '78687873783', 
+                name: 'Gratin', 
+                category: 'Dish',
+            }
+            const recipe_2 = {
+                id: '65464646155',
+                name: 'Cheesecake',
+                category: 'Dessert',
+                nested: [
+                    {
+                        id: '458445',
+                        name: 'test-1',
+                    },
+                    {
+                        id: '88488',
+                        name: 'test-2',
+                    },
+                    {
+                        id: '458455',
+                        name: 'test-3',
+                    },
+                ],
+            }
+            const recipe_3 = {
+                id: '12335373873',
+                name: 'Soupe',
+                category: 'Starter',
+            }
+            await db.push('/recipes[0]', recipe_1, true)
+            await db.push('/recipes[1]', recipe_2, true)
+            await db.push('/recipes[2]', recipe_3, true)
+
+            const routerPathStyle = '/recipes/65464646155/nested/88488'
+
+            const normalPath = await db.fromPath(routerPathStyle)
+
+            expect(normalPath).toEqual('/recipes[1]/nested[1]')
+        })
+        test('should convert a router style path to a normal path using other propertyName', async () => {
+            const recipe_1 = {
+                _id: '78687873783', 
+                name: 'Gratin', 
+                category: 'Dish',
+            }
+            const recipe_2 = {
+                _id: '65464646155',
+                name: 'Cheesecake',
+                category: 'Dessert',
+                nested: [
+                    {
+                        _id: '458445',
+                        name: 'test-1',
+                    },
+                    {
+                        _id: '88488',
+                        name: 'test-2',
+                    },
+                    {
+                        _id: '458455',
+                        name: 'test-3',
+                    },
+                ],
+            }
+            const recipe_3 = {
+                _id: '12335373873',
+                name: 'Soupe',
+                category: 'Starter',
+            }
+            await db.push('/recipes[0]', recipe_1, true)
+            await db.push('/recipes[1]', recipe_2, true)
+            await db.push('/recipes[2]', recipe_3, true)
+
+            const routerPathStyle = '/recipes/65464646155/nested/88488'
+
+            const normalPath = await db.fromPath(routerPathStyle, '_id')
+
+            expect(normalPath).toEqual('/recipes[1]/nested[1]')
+        })
+    })
     describe('Cleanup', () => {
         test('should remove the test files', async () => {
             fs.unlinkSync('test/recipe.json')

test/JsonDB.test.ts

@@ -96,6 +96,39 @@ describe('JsonDB', () => {
         })
     })
 
+    describe('fromPath()', () => {
+        test('should throw path error when not found item',() => {
+            db.getData = jest.fn(async () => ({
+                a: [
+                    {
+                        id: '1'
+                    }
+                ]
+            }))
+
+            expect(async () => {
+                await db.fromPath('/a/1')
+            }).rejects.toThrow(
+                'DataPath: /a/1 not found.'
+            )
+        })
+        test('should throw path error when not found item and using a wrong propertyName',() => {
+            db.getData = jest.fn(async () => ({
+                a: [
+                    {
+                        id: '1'
+                    }
+                ]
+            }))
+
+            expect(async () => {
+                await db.fromPath('/a/1', '_id')
+            }).rejects.toThrow(
+                'DataPath: /a/1 not found.'
+            )
+        })
+    })
+
     // Test was made for code coverage for getParentData, but this cannot return null or undefined.
     // Commented out the test and the checks in JsonDB.ts.
     // describe('push()', () => {