Configuration Parameters

MARS configuration is a name/value store (TMARSParameters) available at the engine and application levels. Values are typically loaded from an .ini file next to the executable with FEngine.Parameters.LoadFromIniFile, and can be read in code or injected with [EngineParam] / [ApplicationParam].

[Engine]
Port=8080
ThreadPoolSize=75
BasePath=/rest

[DefaultApp]
JWT.Secret=please-change-me
JWT.Duration=1

When AddApplication runs, the engine copies the matching .ini section (by application name) into the application's parameters.

Engine parameters

Parameter	Type	Default	Purpose
Port	Integer	8080	HTTP listening port.
PortSSL	Integer	0	HTTPS port (0 = disabled).
ThreadPoolSize	Integer	75	Worker threads (size for concurrent requests, incl. open SSE streams).
BasePath	string	/rest	Root path stripped from every URL before application matching.

CORS-related parameters (when CORS is enabled) include CORS.Origin, CORS.Methods, CORS.Headers. See Engine ▸ CORS.

JWT / authentication parameters (per application)

Read by the token resource and JWT backends:

Parameter	Default	Purpose
JWT.Secret	(a fixed GUID — change it!)	HMAC signing secret.
JWT.Issuer	MARS-Curiosity	iss claim.
JWT.Duration	1	Token lifetime in days.
JWT.Duration.InMinutes	—	Lifetime in minutes (alternative).
JWT.Duration.InSeconds	—	Lifetime in seconds (alternative).
JWT.CookieEnabled	true	Also deliver/accept the token as a cookie.
JWT.CookieName	access_token	Cookie name.
JWT.CookieDomain	—	Cookie domain.
JWT.CookiePath	—	Cookie path.
JWT.CookieSecure	false	Mark the cookie Secure (HTTPS only).

Change JWT.Secret

The default secret ships in the public source. Always set a strong, unique secret per deployment.

FireDAC parameters

Connection definitions live under a slice (commonly FireDAC) and are loaded with TMARSFireDAC.LoadConnectionDefs(FEngine.Parameters, 'FireDAC'). Each named definition maps to a FireDAC ConnectionDefName with its usual driver-specific keys (DriverID, Database, Server, User_Name, Password, pooling options, …). See FireDAC & Datasets.

Reading and injecting parameters

// In code
var LPort := FEngine.Parameters.ByName('Port').AsInteger;
var LSecret := LApp.Parameters.ByName('JWT.Secret').AsString;

// Injected into a resource
[Path('cfg')]
TCfgResource = class
  [EngineParam('Port', 8080)]       Port: Integer;
  [ApplicationParam('JWT.Secret')]  Secret: string;
end;

Provide a default as the second argument to ByName/[EngineParam]/[ApplicationParam] so missing keys degrade gracefully.

Custom parameters

You can add your own keys to the .ini and read/inject them the same way — a convenient place for feature flags, external service URLs, file paths, etc.

[DefaultApp]
Feature.NewSearch=true
Storage.Path=C:\data\uploads

[ApplicationParam('Storage.Path')] StoragePath: string;