tubeulator 0.1.2

TfL open data interface library.

tubeulator

It's time for the tubeulator

TfL open data interface library.

Key features

• Route planning (underground, overground, bus, walking)
• Time estimation taking into account mixed modes of travel in one journey

Requires

• Python 3.9+
• MongoDB

Installation

tubeulator is available from PyPI, and the code is on GitHub

Install using pip:

pip install tubeulator

The suggested local environment installation is stored in CONDA_SETUP.md:

conda create -n tubeulator "python=3.11"
conda activate tubeulator
pip install -r requirements.txt

You can install MongoDB globally or just in the environment (conda install mongodb)

Usage

There are currently generated API methods for all of the APIs!

Outline of current usage:

>>> import tubeulator
>>> modes = tubeulator.fetch.line.meta_modes()
>>> modes
[Mode(IsTflService=True, IsFarePaying=True, IsScheduledService=True, ModeName='bus'),
 Mode(IsTflService=True, IsFarePaying=True, IsScheduledService=True, ModeName='cable-car'),
 Mode(IsTflService=False, IsFarePaying=True, IsScheduledService=True, ModeName='coach'),
 Mode(IsTflService=False, IsFarePaying=False, IsScheduledService=False, ModeName='cycle'),
 Mode(IsTflService=True, IsFarePaying=True, IsScheduledService=False, ModeName='cycle-hire'),
 Mode(IsTflService=True, IsFarePaying=True, IsScheduledService=True, ModeName='dlr'),
 Mode(IsTflService=True, IsFarePaying=True, IsScheduledService=True, ModeName='elizabeth-line'),
 Mode(IsTflService=False, IsFarePaying=False, IsScheduledService=False, ModeName='interchange-keep-sitting'),
 Mode(IsTflService=False, IsFarePaying=False, IsScheduledService=False, ModeName='interchange-secure'),
 Mode(IsTflService=False, IsFarePaying=True, IsScheduledService=True, ModeName='national-rail'),
 Mode(IsTflService=True, IsFarePaying=True, IsScheduledService=True, ModeName='overground'),
 Mode(IsTflService=True, IsFarePaying=True, IsScheduledService=True, ModeName='replacement-bus'),
 Mode(IsTflService=True, IsFarePaying=True, IsScheduledService=True, ModeName='river-bus'),
 Mode(IsTflService=True, IsFarePaying=True, IsScheduledService=True, ModeName='river-tour'),
 Mode(IsTflService=False, IsFarePaying=False, IsScheduledService=False, ModeName='taxi'),
 Mode(IsTflService=True, IsFarePaying=True, IsScheduledService=True, ModeName='tram'),
 Mode(IsTflService=True, IsFarePaying=True, IsScheduledService=True, ModeName='tube'),
 Mode(IsTflService=False, IsFarePaying=False, IsScheduledService=False, ModeName='walking')]

Planned

Outline of expected usage:

>>> import tubeulator
>>> j = tubeulator.Journey(A="Shoreditch High Street", B="Tooting Bec")
[INFO] Found 3 routes [1: (Tube,Tube,Walk) 2: (Tube,Tube,Bus), 3: (Overground,Tube)].
[INFO] Selected 1 as best route (fastest).
...

Actual current usage (doesn't work for Shoreditch because it is ambiguous, here's an unambiguous free-text query):

>>> import tubeulator
>>> j = tubeulator.fetch.journey.journey_results("Bow Road Underground Station", "Tooting Bec Underground Station")
>>> print(len(j.Journeys))
3
>>> [jj.Fare.TotalCost for jj in j.Journeys]
[300, 300, 300]
>>> pprint(j.Journeys[0].Legs[0].Instruction)
Instruction(Summary='Hammersmith & City line to Mile End',
            Detailed='Hammersmith & City line towards Hammersmith (H&C and '
                     'Circle Lines)',
            Steps=[])
>>> pprint([l.Instruction.Summary for l in j.Journeys[0].Legs])
['Hammersmith & City line to Mile End',
 'Central line to Bank',
 'Northern line to Tooting Bec']
>>> pprint([l.Instruction.Summary for l in j.Journeys[1].Legs])
['District line to Monument',
 'Walk to Bank',
 'Northern line to Tooting Bec']
>>> pprint([l.Instruction.Summary for l in j.Journeys[2].Legs])
['Hammersmith & City line to Mile End',
 'Central line to Bank',
 'Northern line to Tooting Bec']
>>> pprint(j.Journeys[0])
Journey(StartDateTime=datetime.datetime(2023, 5, 30, 22, 28),
        Duration=35,
        ArrivalDateTime=datetime.datetime(2023, 5, 30, 23, 3),
        Legs=[Leg(Duration=1,
                  Speed=None,
                  Instruction=Instruction(Summary='Hammersmith & City line to '
                                                  'Mile End',
                                          Detailed='Hammersmith & City line '
                                                   'towards Hammersmith (H&C '
                                                   'and Circle Lines)',
                                          Steps=[]),
                  Obstacles=[Obstacle(Type='WALKWAY',
                                      Incline='LEVEL',
                                      StopId=1000146,
                                      Position='AFTER')],
                  DepartureTime=datetime.datetime(2023, 5, 30, 22, 28),
                  ArrivalTime=datetime.datetime(2023, 5, 30, 22, 29),
                  DeparturePoint=Point(Lat=51.526934656609995,
                                       Lon=-0.02494089054),
                  ArrivalPoint=Point(Lat=51.52536768912,
                                     Lon=-0.033370024490000004),
                  Path=Path(LineString='[[51.52694645478, '
                                       '-0.02493847399],[51.52696258512, '
...

Possible features to customise the Journey:

• via (routes, locations)
• avoid (e.g. busy areas, or a particular interconnection)
• prefer (fastest, least walking)

Storage

A good option for storage would be to use MongoDB (PyMongo) as done in this project. This would require the user to set up and run a MongoDB client with mongod, then the program would connect to it on localhost.

For simplicity, I store the data in the package itself (under src/tubeulator in this repo, which would be retained when distributed as an installed package in site-packages), rather than the default /data/db at the root of my file system.

The program will not create this directory within its package directory if there is already an instance of MongoDB running (mongod) to connect to. To supply a different database path, run the following and substitute your path of choice:

mkdir -p data/db
mongod --dbpath data/db

Data is stored in JSON-style documents (represented as dictionaries in PyMongo), converted from Python types to BSON types under the hood.

API fetching and parsing into DTO dataclasses

The TfL APIs are fetched in the normal way. The methods are exposed via an interface in the tubeulator.fetch module, so you can explore the available routes by tab completion under there.

When the response is received, a dataclass made for the expected data is immediately called to parse the JSON. These dataclasses were generated from the API schema itself by the tubeulator.codegen modules, and can be regenerated by calling tubeulator populate (which 'populates' the tubeulator.generated subpackage with modules for each of the API schemas).

We call such a dataclass a 'DTO' or data transfer object, but essentially it's just a Python dataclass, which may include other DTOs thanks to the interlinked referential structure of the API schema.

Data collection approach

The available network is a configuration, liable to change (stations may open/close temporarily/permanently).

However the network is also fairly static: it can be expected to remain fixed in the short-term.

This situation motivates an incremental method of collection that builds from dynamically downloaded components (rather than hard-coding aspects liable to change), and can therefore be regenerated in response to change.

Most of these can be found by looking for Meta API names in the main Swagger doc. For Line these are Modes, Severity, DisruptionCategories and ServiceTypes. For StopPoint these are Categories, StopTypes and Modes.

• Enumerate valid modes (Line/Meta/Modes or equivalently StopPoint/Meta/Modes)

  • For a 'tube' network I would include tube, elizabeth-line, dlr, overground, tflrail, national-rail, and at a push bus and replacement-bus.
  • For representing interchange I might include: walking, interchange-keep-sitting, and interchange-secure.
  • I would not include: taxis, river boats, trams, bikes, coaches, cable cars.

• Enumerate lines that serve the selected modes (Line/Mode/{modes})

  • For example:
    • The elizabeth-line mode has a single Line entity, id = "elizabeth", name = "Elizabeth line".
    • The dlr mode has a single Line entity, id = "dlr", name = "DLR"
    • The tube mode has 11 Line entities, the first has id "bakerloo" and name "Bakerloo" (etc). Some tube lines have both "Regular" and "Night" serviceTypes.

• Enumerate the types of StopPoint that are applicable to the selected modes (StopPoint/Meta/StopTypes)

  • For a 'tube' network I would include "NaptanMetroAccessArea", "NaptanMetroEntrance", "NaptanMetroPlatform", "NaptanMetroStation", "NaptanRailAccessArea", "NaptanRailEntrance", "NaptanRailPlatform", "NaptanRailStation", "TransportInterchange", "NaptanFlexibleZone", "NaptanUnmarkedPoint".
    • Unfortunately NaptanMetroStation describes both tube stations and cable car 'stations' (at Greenwich), as seen when obtaining all stop points of a given type
  • At a push I would include "NaptanBusCoachStation", "NaptanBusWayPoint", "NaptanMarkedPoint", "NaptanOnstreetBusCoachStopCluster", "NaptanOnstreetBusCoachStopPair", "NaptanPrivateBusCoachTram", "NaptanPublicBusCoachTram".
  • I would exclude "CarPickupSetDownArea", "NaptanAirAccessArea", "NaptanAirEntrance", "NaptanAirportBuilding", "NaptanCoachAccessArea", "NaptanCoachBay", "NaptanCoachEntrance", "NaptanCoachServiceCoverage", "NaptanCoachVariableBay", "NaptanFerryAccessArea", "NaptanFerryBerth", "NaptanFerryEntrance", "NaptanFerryPort", "NaptanHailAndRideSection", "NaptanLiftCableCarAccessArea", "NaptanLiftCableCarEntrance", "NaptanLiftCableCarStop", "NaptanLiftCableCarStopArea", "NaptanSharedTaxi", "NaptanTaxiRank"

• List the stations for the given line IDs (Line/{id}/StopPoints[?tflOperatedNationalRailStationsOnly])

  • Each entry returned (alphabetically) has
    • a commonName (readable title)
    • lat and lon floating points
    • modes e.g. ['bus', 'tube']
    • lines, a list of dicts of each line, for all modes, with an id (e.g. district), proper name (e.g. District), uri (which seems to just be /Line/{id}. The mode is not indicated for each line.
    • lineGroup is again a list of dicts, whose purpose seems to be to indicate the side of the road for a bus, for each line
    • lineModeGroups is again a list of dicts, which indicates the mode for each line (grouped by mode).
    • children list with the same commonName but distinct naptanId (presumably these are for each platform/direction.
  • Note that the child nodes do not have populated modes ([]), lat or lon (0.0).

(TBC)

Dataclass Wizard

This project used to depend on:

"dataclass_wizard @ git+https://github.com/rnag/dataclass-wizard.git@WIP-support-cyclic-references",

but this was removed for portability after switching the DTOs to Pydantic (for distribution to PyPI).

Distributing

Note: to distribute you must clone a fresh copy or delete the data/db as this seems to be detected and will prevent upload (perhaps as it detects secrets)