flecs-dash

Web-based dashboard for flecs. This project is still under development and may change a lot!

Usage

The dashboard requires the following modules:

Module	Description
flecs.meta	Reflection for Flecs components
flecs.json	JSON serializer for Flecs components
flecs.rest	A REST interface for introspecting & editing entities
flecs.monitor	Web-based monitoring
flecs.player	Play, stop and pause simulations
flecs.components.http	Components describing an HTTP server
flecs.systems.civetweb	HTTP server implementation
flecs.dash	The dashboard (this project)

Add the module source & header file (from the repository root) to your project for each dependency
Copy the flecs-dash/etc directory in this repository to etc/flecs-dash under your project root directory
Configure a threading implementation in the OS API (see below)

If your project root directory is my_app, then your directory structure should look like this:

my_app/etc/flecs-dash/apps
my_app/etc/flecs-dash/css
my_app/etc/flecs-dash/images
my_app/etc/flecs-dash/js
my_app/etc/flecs-dash/favicon.png
my_app/etc/flecs-dash/index.html

To add the dashboard to a C application, do:

ECS_IMPORT(world, FlecsDash);
ECS_IMPORT(world, FlecsSystemsCivetweb);

ecs_set(world, 0, EcsDashServer, {.port = 9090});

To add it to a C++ application, do:

world.import<flecs::dash>();
world.import<flecs::systems::civetweb>();

ecs.entity().set<flecs::dash::Server>({9090});

Important: Make sure to start your application from the project root directory. This ensures that the dashboard code can find the web resources. Go to http://localhost:9090 to open the dashboard.

Setting up OS API

The webserver requires a threading implementation to be configured in the Flecs OS API. You can do this yourself, or add this example as a dependency to your project: https://github.com/SanderMertens/flecs/tree/master/examples/os_api/flecs-os_api-posix. When using this example, make sure to add this before creating the world:

posix_set_os_api();

Using flecs.dash with bake

When using bake, clone & build the above modules and add them as dependencies to your project. Additionally, build & add the bake OS API example from the flecs repository as well.

{
  "id": "my_app",
  "type": "application",
  "value": {
    "use": [
      "flecs", 
      "flecs.dash",
      "flecs.systems.civetweb", 
      "flecs.os_api.bake"
    ]
  }
}

Before creating the world, call this function to install the bake OS API:

bake_set_os_api();

Add the above code for creating the server to your application. You can now run the application from anywhere with bake run. You don't need to copy the web files to your project root, as it will be automatically discovered by the bake runtime.

Troubleshooting

My application crashes when I import the flecs.dash!

This is likely because you did not set an OS API implementation for threading functions, as the server needs synchronization to safely access the world. See Setting up OS API for how to add this to the application.

I'm not using bake, can I still use the dashboard?

Absolutely, the dashboard has no dependencies on bake. As long as all the modules are cloned, and the server can find the dashboard web resources, it will work with any buildsystem.

I'm using bake, do I still need to copy files to my project?

Not if you set the bake OS API (see Flecs examples folder) with bake_set_os_api(). This will register a function with Flecs that automatically finds the files.

My application is running, but if I open a browser I get a 404 error (no page found)

Good news, the server is running! The most likely cause of this is that the server process cannot find the web resources. Make sure to copy the files to the right location as is described in Usage. Also ensure that the working directory (typically the location from which the application is started) is the project root.

My application is running, but if I open a browser I get a server error!

This means that the browser cannot find a server on the specified port. Make sure you're using the correct IP address and port.

I need to store the resources in a different folder, is this possible?

Yes. If you cannot store your flecs dash resources in the location mentioned above, you can provide a custom location with the "module_to_etc" OS API function. This function overrides the default behavior of Flecs to locate files. To do this, add a function like this to your code:

char* my_module_to_etc(const char* module_name) {
    // Simple fix to make flecs.dash work. Can be made more generic by using the module_name to generate the path
    return ecs_os_strdup("path_to_dash_files");
}

int main(int argc, char *argv[]) {
  // set OS API with *_set_os_api function
  
  // Override default module_to_etc
  ecs_os_api.module_to_etc_ = my_module_to_etc;
}

Verify that the path you provide points directly to the files, so if you do path + "/index.html, it points to the file.

flecs-hub/flecs-dash