refactor: ensure symlinks are relative to allow moving databases around

chore: bump version (broke things with this refactor, might as well)

deno.json

@@ -1,6 +1,6 @@
 {
 	"name": "@andyburke/fsdb",
-	"version": "0.9.0",
+	"version": "1.0.0",
 	"license": "MIT",
 	"exports": {
 		".": "./fsdb.ts",

indexers/symlinks.ts

@@ -104,7 +104,7 @@ export class FSDB_INDEXER_SYMLINKS<T> implements FSDB_INDEXER<T> {
 				}
 
 				const resolved_item_path = await Deno.readLink(item_file.path);
-				results.push(resolved_item_path);
+				results.push(path.normalize(path.resolve(path.dirname(item_file.path), resolved_item_path)));
 				++counter;
 			}
 
@@ -116,6 +116,44 @@ export class FSDB_INDEXER_SYMLINKS<T> implements FSDB_INDEXER<T> {
 		return results;
 	}
 
+	private async make_symlink(target: string, symlink_path: string) {
+		let tolerate_existing = false;
+		try {
+			const existing_link_stat = await Deno.lstat(symlink_path);
+			if (!existing_link_stat.isSymlink) {
+				throw new Deno.errors.AlreadyExists(
+					`There is an existing filesystem entry (not symlink) at ${symlink_path} while attempting to point to ${target}`
+				);
+			}
+
+			const existing_link_target = await Deno.readLink(symlink_path);
+			const resolved_link_target = path.resolve(existing_link_target);
+			const resolved_target = path.resolve(target);
+
+			if (resolved_link_target !== resolved_target) {
+				throw new Deno.errors.AlreadyExists(
+					`A symlink (${symlink_path}) already exists pointing to (${resolved_link_target}), failed to create one pointing to: ${resolved_target}`
+				);
+			}
+
+			tolerate_existing = true;
+		} catch (error) {
+			if (!(error instanceof Deno.errors.NotFound)) {
+				throw error;
+			}
+		}
+
+		await Deno.mkdir(path.dirname(symlink_path), { recursive: true });
+
+		try {
+			await fs.ensureSymlink(target, symlink_path);
+		} catch (error) {
+			if (!(error instanceof Deno.errors.AlreadyExists) || !tolerate_existing) {
+				throw error;
+			}
+		}
+	}
+
 	async index(item: T, authoritative_path: string): Promise<string[]> {
 		if (typeof this.config.root !== 'string') {
 			throw new Error('root should have been set by FSDB instance');
@@ -171,9 +209,8 @@ export class FSDB_INDEXER_SYMLINKS<T> implements FSDB_INDEXER<T> {
 			}
 
 			// create index symlink and reverse link
-			await Deno.mkdir(path.dirname(symlink_path), { recursive: true });
+			await this.make_symlink(path.relative(path.dirname(symlink_path), authoritative_path), symlink_path);
-			await fs.ensureSymlink(authoritative_path, symlink_path);
+			await this.make_symlink(path.relative(path.dirname(reverse_link_path), symlink_path), reverse_link_path);
-			await fs.ensureSymlink(symlink_path, reverse_link_path);
 
 			results.push(symlink_path);
 		}
@@ -193,13 +230,14 @@ export class FSDB_INDEXER_SYMLINKS<T> implements FSDB_INDEXER<T> {
 			}
 
 			const index_symlink_path: string = await Deno.readLink(item_dir_reverse_link);
-			if (fs.existsSync(index_symlink_path)) {
+			const resolved_index_symlink_path: string = path.resolve(path.join(item_dir, index_symlink_path));
-				await Deno.remove(index_symlink_path);
+			if (fs.existsSync(resolved_index_symlink_path)) {
-				results.push(index_symlink_path);
+				await Deno.remove(resolved_index_symlink_path);
+				results.push(resolved_index_symlink_path);
 			}
 
 			await Deno.remove(item_dir_reverse_link);
-			results.push(...await cleanup_empty_directories(index_symlink_path));
+			results.push(...await cleanup_empty_directories(resolved_index_symlink_path));
 		}
 
 		return results;