Add swa.json config file

[manekinekko]

Describe the solution you'd like
As a user, I'd like to be able to start swa using a config file. All the CLI flags should be supported.

{
  "options": {
   // CLI flags
  }
}

File name options:

• swa.json
• swa.config.json
• .swarc
• swa property in package.json

[itpropro]

• swa property in package.json could lead to problems with monorepos
• swa.json not really clear that it's a config file
• swa.config.json, .swarc both fine for me

I would prefer .swarc, as I think the most important thing about the naming would be to avoid confusion with the staticwebapp.config.json file for the user.

[k-miyake]

I assume that staticwebapp.config.json is already enabled as mentioned in this docs. Does this issue mean that the file name may be changed in the future?

I think staticwebapp.config.json is too long and I like swa.config.json.

[manekinekko]

@k-miyake sorry about the confusion:

• staticwebapp.config.json is the config file for your project deployed on SWA
• swa.config.json (name to be defined) would be the config file for the CLI.

Do you have other suggestions for the CLI config file?

[k-miyake]

@manekinekko I was mistaken, sorry.
In this issue, discussing a different file than staticwebapp.config.json.

It is preferable to use a file name that indicates it is for development.
For example, swa.development.json or local.development.json.

[anthonychu]

For naming, thinking something like swa-cli.config.json so it's clear that it's for the CLI.

For contents, I think we can start with a single prop named configurations (not sure what else to name them, maybe environments? contexts?).

{
  "configurations": {
    "app1": {
      "context": "./static",
      "api": "./api"
    },
    "app2": {
      "context": "http://localhost:3000",
      "app-startup-command": "cd frontend && npm start", // proposed in #147
      "api": "./api"
    }
  }
}

If there's a single configuration, swa start can just use it.

If there's more than one, use swa start app1. If there's a folder of the same name, the CLI will prefer the config file.

If swa start is run without a context, perhaps use interactive prompts to create the file. (this is lower priority and can be a separate issue)

[alexweininger]

I really like this feature. I'm exploring adding local debugging for SWAs into the VS Code extension and this would make the configuration much easier on users.

I think users would be much more comfortable editing a swa-cli.config.json versus launch/tasks.json files.