TryGetDeveloperOverride, invoked from GetSettingFromDictionary
Trigger
Every call to Get setting value (via GetConfigSetting/GetConfigSettingAsync → GetSettingFromDictionary), once DeveloperSettingsOverrideFile has been set by Initialize environment client step 7
Inputs
dictKey (the already-composed "{section}.{configKey}" or bare configKey), DeveloperSettingsOverrideFile path
Outputs
A matching ConfigSetting from the override file, or no result (falls through to the loaded Settings dictionary)
If DeveloperSettingsOverrideFile is null (file absent, or the machine is not a developer machine, or the configured path did not exist at startup), return false immediately with no override.
Otherwise, wrap the rest of the lookup in a bare try/catch { }: any exception — a missing/unreadable file, malformed JSON, a null deserialized array, and so on — is silently swallowed, and the method falls through to return false as if no override file were configured at all (BR-EC-27).
Read and parse the override file as a JSON array of ConfigSetting objects on every call — there is no caching of the parsed file.
For each parsed entry, compute its formatted key via GetFormattedKey(setting.ConfigKey) — "{Section}.{Key}" when ConfigKey.Section is non-empty, otherwise just Key — and compare it to dictKey using a case-insensitive (OrdinalIgnoreCase) match.
Return the first entry whose formatted key matches; the matched entry is returned as a whole ConfigSetting (not just its value), so it takes precedence over any value loaded from the Environment API for this lookup.
If no entry matches, return false and the caller proceeds to look the key up in the loaded Settings dictionary.
Because Get setting value substitutes TrackName for a blank section before composing dictKey, a section-less override entry in the file must have its ConfigKey.Section set to the resolved track name (or be matched via the bare-key form) to be found — the lookup only operates on the already section-qualified composed key, it does not retry with alternate section candidates.
This lookup is reached only from the non-secureGetSettingValue* path (via GetConfigSetting/GetSettingFromDictionary); HasSetting, GetSectionSettings, and the secure-setting path never consult the override file.
flowchart TD
A["TryGetDeveloperOverride dictKey"] --> B{DeveloperSettingsOverrideFile set?}
B -- No --> C["No override: fall through"]
B -- Yes --> D["Read + parse override file as JSON<br>(wrapped in catch-all try/catch)"]
D -->|any exception| C
D -->|parsed OK| E{"First entry whose formatted<br>key matches dictKey?"}
E -- Yes --> F[Return matched ConfigSetting]
E -- No --> C