feat: introduce replace placeholders for prompts

packages/spacecat-shared-utils/src/helpers.js

@@ -92,3 +92,21 @@ export function generateCSVFile(data) {
   const json2csvParser = new Parser();
   return Buffer.from(json2csvParser.parse(data), 'utf-8');
 }
+
+/**
+ * Replaces placeholders in the prompt content with their corresponding values.
+ *
+ * @param {string} content - The prompt content with placeholders.
+ * @param {Object} placeholders - The placeholders and their values.
+ * @returns {string} - The content with placeholders replaced.
+ */
+export function replacePlaceholders(content, placeholders) {
+  return content.replace(/{{(.*?)}}/g, (match, key) => {
+    if (key in placeholders) {
+      const value = placeholders[key];
+      return typeof value === 'object' && value !== null ? JSON.stringify(value) : value;
+    } else {
+      return match;
+    }
+  });
+}

packages/spacecat-shared-utils/src/index.d.ts

@@ -143,6 +143,15 @@ declare function getRUMDomainKey(baseURL: string, ctx: object): Promise<string>;
  */
 declare function generateCSVFile(data: object[]): Buffer;
 
+/**
+ * Replaces placeholders in the prompt content with their corresponding values.
+ *
+ * @param {string} content - The prompt content with placeholders.
+ * @param {Object} placeholders - The placeholders and their values.
+ * @returns {string} - The content with placeholders replaced.
+ */
+declare function replacePlaceholders(content: string, placeholders: object): string;
+
 /**
  * Retrieves stored metrics from S3.
  * @param config - Configuration object

packages/spacecat-shared-utils/test/helpers.test.js

@@ -18,7 +18,9 @@ import nock from 'nock';
 import {
   generateCSVFile,
   resolveSecretsName,
-  resolveCustomerSecretsName, getRUMDomainKey,
+  resolveCustomerSecretsName,
+  getRUMDomainKey,
+  replacePlaceholders,
 } from '../src/helpers.js';
 
 describe('resolveSecretsName', () => {
@@ -188,3 +190,40 @@ describe('generateCSVFile', () => {
     expect(csvString).to.equal(expectedCsv);
   });
 });
+
+describe('replacePlaceholders', () => {
+  it('replaces placeholders with corresponding values', () => {
+    const content = 'Hello, {{name}}!';
+    const placeholders = { name: 'John' };
+    const result = replacePlaceholders(content, placeholders);
+    expect(result).to.equal('Hello, John!');
+  });
+
+  it('does not replace placeholders if key is not found in placeholders object', () => {
+    const content = 'Hello, {{name}}!';
+    const placeholders = { age: 30 };
+    const result = replacePlaceholders(content, placeholders);
+    expect(result).to.equal('Hello, {{name}}!');
+  });
+
+  it('replaces multiple placeholders with corresponding values', () => {
+    const content = 'Hello, {{name}}! You are {{age}} years old.';
+    const placeholders = { name: 'John', age: 30 };
+    const result = replacePlaceholders(content, placeholders);
+    expect(result).to.equal('Hello, John! You are 30 years old.');
+  });
+
+  it('replaces placeholders with stringified objects if value is an object', () => {
+    const content = 'User: {{user}}';
+    const placeholders = { user: { name: 'John', age: 30 } };
+    const result = replacePlaceholders(content, placeholders);
+    expect(result).to.equal('User: {"name":"John","age":30}');
+  });
+
+  it('leaves placeholders unchanged if they are not found in placeholders object', () => {
+    const content = 'Hello, {{name}}! You are {{age}} years old.';
+    const placeholders = { name: 'John' };
+    const result = replacePlaceholders(content, placeholders);
+    expect(result).to.equal('Hello, John! You are {{age}} years old.');
+  });
+});