Validate Settings

Stable

Validating settings resolves each configured path by expanding environment variables and applying platform defaults, then checks whether each resolved path exists on disk. The result is used by the UI to determine whether the Daemon is ready to install and activate mods.

Property	Value
Applies to	Daemon
Trigger	Client requests a readiness check on path configuration
Preconditions	None

Inputs

There are no inputs. The operation reads from the Daemon's stored settings.

Assertions

Assertion	Status
None — the operation always returns a result, even if all paths are unconfigured

Outputs

SettingsValidationResult : An object with a top-level valid flag and a SettingsValidationEntry for each of the three paths.

valid : true only when all three paths resolve successfully and exist on disk. false otherwise.

SettingsValidationEntry (per field) : One of four forms:

- `{ exists: true, resolvedPath: string }` — path resolved and confirmed present on disk.
- `{ exists: false, resolvedPath: string }` — path resolved but not found on disk.
- `{ exists: false, resolvedPath: undefined }` — path could not be resolved (no stored value and the platform default contains an unexpanded environment variable).
- `{ exists: false, resolvedPath: string, error: string }` — path resolved but the filesystem check itself failed.

Effects

None. This is a read-only operation.

Path resolution

Each path is resolved using the following steps:

Use the stored value if present; otherwise fall back to the platform default.
Expand environment variables (%VAR% on Windows; $VAR and ${VAR} on POSIX).
If any placeholder remains unexpanded after step 2, treat the path as unresolvable (undefined).
Normalize the path.
Check whether the resolved path exists on disk.

Platform defaults:

Field	Windows default	POSIX default
`dcsWorkingDir`	`%USERPROFILE%\Saved Games\DCS`	`$HOME/Saved Games/DCS`
`dcsInstallDir`	`%PROGRAMFILES%\Eagle Dynamics\DCS World`	`$HOME/Eagle Dynamics/DCS World`
`dropzoneModsDir`	`%LOCALAPPDATA%\DCS Dropzone\Mods`	`$HOME/.local/share/DCS Dropzone/Mods`

Note: If the environment variable referenced by a platform default is not defined on the host system, the path is unresolvable and resolvedPath is undefined. This can occur on non-standard Windows configurations where %USERPROFILE% or %LOCALAPPDATA% are not set.

Behavior

mermaid

flowchart TD
    Start([validate]) --> PerField[For each of dcsWorkingDir, dcsInstallDir, dropzoneModsDir]

    PerField --> Stored{Stored value<br/>present?}
    Stored -- Yes --> UseStored[Use stored value]
    Stored -- No --> UseDefault[Use platform default]

    UseStored --> Expand[Expand environment variables]
    UseDefault --> Expand

    Expand --> Leftover{Unexpanded placeholder<br/>remains?}
    Leftover -- Yes --> Unresolvable["{ exists: false, resolvedPath: undefined }"]
    Leftover -- No --> Normalize[Normalize path]

    Normalize --> Check[fileSystem.exists resolvedPath]
    Check -- ok true --> EntryExists["{ exists: true, resolvedPath }"]
    Check -- ok false --> EntryMissing["{ exists: false, resolvedPath }"]
    Check -- err --> EntryError["{ exists: false, resolvedPath, error }"]

    Unresolvable --> Aggregate
    EntryExists --> Aggregate
    EntryMissing --> Aggregate
    EntryError --> Aggregate

    Aggregate[Aggregate all three entries] --> Valid{"All three<br/>exists === true?"}
    Valid -- Yes --> Done(["{ valid: true, ... }"])
    Valid -- No --> DoneInvalid(["{ valid: false, ... }"])

    style Done fill:#4ade80,color:#000
    style DoneInvalid fill:#fb923c,color:#fff

Validate Settings ​

Inputs ​

Assertions ​

Outputs ​

Effects ​

Path resolution ​

Behavior ​

See Also ​