low-level-design/map-navigator.text at main · Circles24/low-level-design · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
Design Maps Navigator

Requirements

  User should be able to query path from point A to point B
  It should support different transportation types walk, bike, car, bus, train, hybrid
  User should be able to inspect the complete path which it queried
  User should be able to start navigation where system can help user with the current step and the next turn if applicable
  Path should show the expected ETA and its breakup as well


Entities
1. User
2. Point (abstract)
3. Well known point
4. Coordinate point
5. Journey
6. Step
7. Edge
8. Direction
9. Active journey
10. Mode

Entitiy details

1. User
  a. id
  b. name
  c. email
  d. phone number
  e. status
  ...

2. Point

3. Well known point
  a. id
  b. name
  c. x coordinate
  d. y coordinate
  e. photos
  ...

4. Coordinate Point
  a. x coordinate
  b. y coordinate

5. Direction
  a. source
  b. destination

6. Edge
  a. ROAD
  b. FERRY
  c. RAILWAY
  d. ROAD

7. Road type
  a. HIGHWAY
  b. SERVICE_ROAD
  c. CONNECTING_ROAD

8. Road
  a. id
  b. name
  c. road type
  d. source
  e. destination

9. Step
  a. edge
  b. direction
  c. start point
  d. end point
  e. expected start time
  f. expected end time
  g. is last
  h. followed by turn

10. Journey
  a. source point
  b. destination point
  c. expected total eta
  d. List<Step> steps

11. Active journey
  a. journey
  b. current location (x, y coordinates)
  c. current step

12. Mode
  a. WALK
  b. BUS
  c. BIKE
  d. TRAIN
  e. CAR

Services

  User service
    get user by id // pk look up in db

  Map Service // just a wrapper on map service provider
    get journey (source point, destination point, mode) : Journey // this is assumed to be in place, ideally should be fetced from a third party service like google maps or similar map service
    load map (center point, radius) // to be used to render the map in the UI
    search (query) : List<Point>

  Journey Service
    start (journey) // post fetching journey user can start navigating
    get current state (active journey) // for a given active journey this returns the current state and the next step ie turn and destination eta etc
    update journey state // to be called by system on a period of time to keep the journey state up to date with the input from location service

  Location service
    get current location // to be used by journey service while navigating


User journey
  1. User logs in // to be handled by auth and user journey
  2. User loads the map into UI using load map
  3. User search for a point
  4. Or else User directly picks point from the map using x, y coordinates
  5. User fetches journey from map service
  6. Map Service returns journey which has further breakup of steps // this takes care of finding route basis users preferences mode and other eta
  7. User starts a journey // this makes the journey active and system makes a active journey object from the journey to keep current state and next step
  8. While routing User keeps on fetching the current state
  9. System keeps on reacting to the updates from the location service