90 lines
3.6 KiB
TypeScript
90 lines
3.6 KiB
TypeScript
import path from 'node:path';
|
|
|
|
export type ScenarioResourceReader = (relativePath: string) => Promise<unknown>;
|
|
|
|
type JsonObject = Record<string, unknown>;
|
|
|
|
const MAX_COMPOSITION_DEPTH = 64;
|
|
|
|
const isJsonObject = (value: unknown): value is JsonObject =>
|
|
typeof value === 'object' && value !== null && !Array.isArray(value);
|
|
|
|
const normalizeResourcePath = (resourcePath: string, sourcePath?: string): string => {
|
|
if (!resourcePath || resourcePath.includes('\\') || path.posix.isAbsolute(resourcePath)) {
|
|
throw new Error(`Scenario extension path is invalid: ${resourcePath || '<empty>'}.`);
|
|
}
|
|
const basePath = sourcePath ? path.posix.dirname(sourcePath) : '.';
|
|
const normalized = path.posix.normalize(path.posix.join(basePath, resourcePath));
|
|
if (normalized === '..' || normalized.startsWith('../') || !normalized.endsWith('.json')) {
|
|
throw new Error(`Scenario extension path escapes the scenario resource root: ${resourcePath}.`);
|
|
}
|
|
return normalized;
|
|
};
|
|
|
|
const readExtensionPaths = (value: unknown, sourcePath: string): string[] => {
|
|
if (value === undefined) {
|
|
return [];
|
|
}
|
|
const entries = typeof value === 'string' ? [value] : value;
|
|
if (!Array.isArray(entries) || entries.length === 0 || entries.some((entry) => typeof entry !== 'string')) {
|
|
throw new Error(`Scenario resource ${sourcePath} has an invalid extends field.`);
|
|
}
|
|
return entries.map((entry) => normalizeResourcePath(entry as string, sourcePath));
|
|
};
|
|
|
|
export const mergeScenarioResources = (base: unknown, override: unknown): unknown => {
|
|
if (!isJsonObject(base) || !isJsonObject(override)) {
|
|
return override;
|
|
}
|
|
|
|
const merged: JsonObject = { ...base };
|
|
for (const [key, value] of Object.entries(override)) {
|
|
Object.defineProperty(merged, key, {
|
|
configurable: true,
|
|
enumerable: true,
|
|
writable: true,
|
|
value: key in merged ? mergeScenarioResources(merged[key], value) : value,
|
|
});
|
|
}
|
|
return merged;
|
|
};
|
|
|
|
/**
|
|
* `extends`를 왼쪽부터 합성하고 마지막에 현재 파일을 적용합니다.
|
|
* 객체는 재귀 병합하고 배열과 scalar는 뒤 레이어의 값으로 교체합니다.
|
|
*/
|
|
export const composeScenarioResource = async (
|
|
entryPath: string,
|
|
readResource: ScenarioResourceReader
|
|
): Promise<JsonObject> => {
|
|
const rootEntry = normalizeResourcePath(entryPath);
|
|
|
|
const compose = async (resourcePath: string, stack: string[]): Promise<JsonObject> => {
|
|
if (stack.length >= MAX_COMPOSITION_DEPTH) {
|
|
throw new Error(`Scenario composition exceeds ${MAX_COMPOSITION_DEPTH} layers at ${resourcePath}.`);
|
|
}
|
|
if (stack.includes(resourcePath)) {
|
|
throw new Error(`Scenario composition cycle: ${[...stack, resourcePath].join(' -> ')}.`);
|
|
}
|
|
|
|
const raw = await readResource(resourcePath);
|
|
if (!isJsonObject(raw)) {
|
|
throw new Error(`Scenario resource ${resourcePath} must be a JSON object.`);
|
|
}
|
|
|
|
let result: unknown = {};
|
|
const nextStack = [...stack, resourcePath];
|
|
for (const extensionPath of readExtensionPaths(raw.extends, resourcePath)) {
|
|
result = mergeScenarioResources(result, await compose(extensionPath, nextStack));
|
|
}
|
|
const resourceBody = Object.fromEntries(Object.entries(raw).filter(([key]) => key !== 'extends'));
|
|
result = mergeScenarioResources(result, resourceBody);
|
|
if (!isJsonObject(result)) {
|
|
throw new Error(`Scenario resource ${resourcePath} did not compose to a JSON object.`);
|
|
}
|
|
return result;
|
|
};
|
|
|
|
return compose(rootEntry, []);
|
|
};
|