Initial framework to make URL DB imports work

langs/en-ca.json

@@ -73,7 +73,8 @@
 			"error": {
 				"db-out-of-date": "Database out of date, please try again.",
 				"document-ID-404": "Cannot find {dbType} with ID: {id}",
-				"no-upload-permission": "Cannot save due to missing the \"Upload Files\" permission."
+				"no-upload-permission": "Cannot save due to missing the \"Upload Files\" permission.",
+				"invalid-import-type": "Invalid import type: {type}"
 			}
 		}
 	}

module/api.mjs

@@ -6,6 +6,7 @@ import { ImageApp } from "./apps/ImageApp.mjs";
 
 // Utils
 import { convertToWebp, getFileSize, hashFile, lastModifiedAt } from "./utils/fs.mjs";
+import { importFromURL } from "./utils/imports.mjs";
 
 export const api = foundry.utils.deepFreeze({
 	Apps: {
@@ -21,5 +22,6 @@ export const api = foundry.utils.deepFreeze({
 			lastModifiedAt,
 			getFileSize,
 		},
+		importFromURL,
 	},
 });

module/utils/imports.mjs

@@ -0,0 +1,70 @@
+import { getFile } from "./fs.mjs";
+
+const { Dialog } = foundry.applications.api;
+const { fetchJsonWithTimeout, mergeObject } = foundry.utils;
+
+const TRUSTED_DOMAINS = new Set([
+	`git.varify.ca`,
+	`cdn.varify.ca`,
+	window.location.host,
+]);
+
+/**
+ * Imports an existing JSON DB into the module's current database.
+ *
+ * @param {string} url The URL pointing to a raw JSON file
+ * @param {`keep`|`replace`|`merge`} type The type of import that should be performed
+ */
+export async function importFromURL(url, type) {
+
+	if (![`keep`, `replace`, `merge`].includes(type)) {
+		ui.notifications.error(_loc(`IT.notifs.error.invalid-import-type`, { type }));
+		return false;
+	};
+
+	const domain = new URL(url);
+	if (!TRUSTED_DOMAINS.has(domain.host)) {
+		const confirmed = await Dialog.confirm({
+			content: `An import is trying to happen from: <br>${url}<br>Do you trust this website?`,
+			rejectClose: false,
+		});
+		if (!confirmed) {
+			return false;
+		};
+	};
+
+	let data;
+	try {
+		data = await fetchJsonWithTimeout(url);
+	} catch (err) {
+		throw err;
+	};
+
+	const images = await getFile(`storage/db/images.json`);
+	const artists = await getFile(`storage/db/artists.json`);
+
+	switch (type) {
+		case `keep`: {
+			importKeepExisting(data, images, artists);
+			break;
+		};
+		case `replace`: {
+			importReplaceExisting(data, images, artists);
+			break;
+		};
+		case `merge`: {
+			await importMerge(data, images, artists);
+			break;
+		};
+	};
+
+	return true;
+};
+
+async function importKeepExisting(data, imageDB, artistDB) {};
+
+async function importReplaceExisting(data, imageDB, artistDB) {};
+
+async function importMerge(data, imageDB, artistDB) {
+	throw `Merge-based importing is not implemented yet`;
+};