server-ts: Convert blob.js

src/services/blob.ts

@@ -0,0 +1,59 @@
+import becca = require('../becca/becca.js');
+import NotFoundError = require('../errors/not_found_error');
+import protectedSessionService = require('./protected_session');
+import utils = require('./utils');
+
+function getBlobPojo(entityName: string, entityId: string) {
+    const entity = becca.getEntity(entityName, entityId);
+    if (!entity) {
+        throw new NotFoundError(`Entity ${entityName} '${entityId}' was not found.`);
+    }
+
+    const blob = becca.getBlob(entity);
+    if (!blob) {
+        throw new NotFoundError(`Blob ${entity.blobId} for ${entityName} '${entityId}' was not found.`);
+    }
+
+    const pojo = blob.getPojo();
+
+    if (!entity.hasStringContent()) {
+        pojo.content = null;
+    } else {
+        pojo.content = processContent(pojo.content, entity.isProtected, true);
+    }
+
+    return pojo;
+}
+
+function processContent(content: Buffer | string | null, isProtected: boolean, isStringContent: boolean) {
+    if (isProtected) {
+        if (protectedSessionService.isProtectedSessionAvailable()) {
+            content = content === null ? null : protectedSessionService.decrypt(content);
+        } else {
+            content = "";
+        }
+    }
+
+    if (isStringContent) {
+        return content === null ? "" : content.toString("utf-8");
+    } else {
+        // see https://github.com/zadam/trilium/issues/3523
+        // IIRC a zero-sized buffer can be returned as null from the database
+        if (content === null) {
+            // this will force de/encryption
+            content = Buffer.alloc(0);
+        }
+
+        return content;
+    }
+}
+
+function calculateContentHash({blobId, content}: { blobId: string, content: Buffer }) {
+    return utils.hash(`${blobId}|${content.toString()}`);
+}
+
+module.exports = {
+    getBlobPojo,
+    processContent,
+    calculateContentHash
+};