[](https://hexdocs.pm/location_simulator)
[](https://hex.pm/packages/location_simulator)
# LocationSimulator
Use for simulating location/GPS (longitude, latitude, elevation) data. Support scalable for test workload.
Source code is available on [Github](https://github.com/ohhi-vn/location_simulator)
Package for using on [Hex.pm](https://hex.pm/packages/location_simulator)
## Achitecture
The library has 3 main part:
1. Supervisor. Lib uses `PartitionSupervisor` for creating worker from config
2. Worker. Generating GPS with user config
3. Callback module. This is defined by user to handle event from worker
### Api call flow
```mermaid
sequenceDiagram
participant CallbackModule
participant Worker
participant Api
participant Supervisor
Api->>Supervisor: Start with workers from config
Supervisor->>Worker: Start GPS generator
Worker->>CallbackModule: call start event
Worker->>CallbackModule: call gps event
Worker->>CallbackModule: call stop event
```
*(for in local you need install extension support for mermaid to view flow)*
## Installation
Library can be installed
by adding `location_simulator` to your list of dependencies in `mix.exs`:
```elixir
def deps do
[
{:location_simulator, "~> 0.4"}
]
end
```
Library need to start before using APIs. If you need start with your app, you could add to `application` function:
```elixir
def application do
[
mod: {YourApp.Application, []},
extra_applications: [:logger, :location_simulator]
]
end
```
If you need to modify source please go to [Github](https://github.com/ohhi-vn/location_simulator) and clone repo or contribute our repo.
## Guide
Start LocationSimulator with default config:
```elixir
LocationSimulator.start()
```
With default config simulator will print location to console by Logger.
Start with your callback & config:
### Generate fake GPS data
```elixir
config =
%{
worker: 3,
event: 100,
interval: 1000,
random_range: 0,
direction: :random,
elevation: 100,
elevation_way: :up,
callback: MyCallbackModule
}
LocationSimulator.start(config)
```
Simulator support directions:
:north, :south, :east, :west, :north_east, :north_west, :south_east, :south_west
If :direction is missed or equal :random, simulator will random a direction for each worker.
With elevation, you can set start level and way :up or :down or no move up/down by any value.
If you want all worker started from same point, you can add :started_gps. In this case elevation config from outside will be ignored.
```elixir
config =
%{
...
started_gps: {20.95991288388162, 107.06662537952286, 0}
}
```
### Load GPS from GPX file
For load GPS data just add a file path with supported wildcard by config `gpx_file`. Some configs are related to GPS can be ignored.
```elixir
config =
%{
worker: 3,
interval: 1000,
gpx_file: "data/*.gpx"
callback: MyCallbackModule
}
LocationSimulator.start(config)
```
If you have multi GPX file matched with `gpx_file` worker will get file depended matched order and rotate if number of files is not enough for workers.
## Example
Start library in Elixir's shell:
```bash
mix deps.get
iex -S mix
iex(1)> LocationSimulator.start()
```
For writing callback module please go to `LocationSimulator.Event` document.
We provide simple demo that generate a GPX file. You can get from [repo](https://github.com/ohhi-vn/location_simulator/tree/main/example/generate_gpx)
