django-wmata-realtime-snapshot 0.2

# WMATA Realtime Snapshot

### Overview

Provide a point-in-time mirror of Washington DC Metro's realtime train schedule

### Installation

1. **Install the package**

```shell
pip install django-wmata-realtime-snapshot
```

1. **Add the app to your django project's settings**

```python
INSTALLED_APPS = (
...
wmata_realtime_snapshot,
)
```

1. **Get a WMATA API key**

If you don't already have a WMATA API account, sign up here: https://developer.wmata.com/signup

Alternatively, you may have success using the demo key provided here: https://developer.wmata.com/Products

Once you have a key, (e.g. `1234IAMAKEY`), you can use it to download a dump of the realtime data.

1. **Download a JSON and/or XML dump from WMATA**

These instructions are for a UNIX based system.

JSON Dump:
```shell
curl https://api.wmata.com/StationPrediction.svc/json/GetPrediction/All?api_key=1234IAMAKEY > realtime_dump.json
```

XML Dump:
```shell
curl https://api.wmata.com/StationPrediction.svc/GetPrediction/All?api_key=1234IAMAKEY > realtime_dump.xml
```

To download both at the same time:

```shell
curl https://api.wmata.com/StationPrediction.svc/json/GetPrediction/All?api_key=1234IAMAKEY > realtime_dump.json & curl https://api.wmata.com/StationPrediction.svc/GetPrediction/All?api_key=1234IAMAKEY > realtime_dump.xml
```

1. **Add your dumps to the Django settings file**

In your Django settings, define the following variables for the dumps you want to serve.

```
WMATA_JSON_DUMP='path/to/realtime_dump.json'
WMATA_XML_DUMP='path/to/realtime_dump.xml'
```

Any endpoint type (json or xml) that does not have a dump file to read will return a json/xml error message when querying the snapshot API:

```json
{"Error": "No JSON resource has been defined. Please read the installation instructions."}
```

```xml
<Error>No XML resource has been defined. Please read the installation instructions.</Error>
```

1. **Add a url endpoint**

```python
url(r'^mirror/', include('wmata_realtime_snapshot.urls', namespace='wmata_realtime_snapshot')),
```

1. **Visit the API**

The API path is the same as the real WMATA API for easy plug-n-play:

```
http://localhost:8000/mirror/StationPrediction.svc/json/GetPrediction/All
http://localhost:8000/mirror/StationPrediction.svc/GetPrediction/B01
http://localhost:8000/mirror/StationPrediction.svc/json/GetPrediction/K08,D13,A05
```