Backstage Custom Action to Append file

Backstage Custom Action to Append File

When working with TypeScript and creating applications using the Backstage framework, you may come across a scenario where you need to append data to a file. This can be achieved by creating a custom action in Backstage that performs the desired file appending operation. In this blog post, we will explore two different solutions to accomplish this task.

Solution 1: Using fs.appendFileSync

The first solution involves using the fs.appendFileSync method provided by Node.js. This method allows us to append data to a file synchronously. Here’s an example of how you can implement this solution:


import { createRouter } from '@backstage/plugin-router';
import { createServiceBuilder } from '@backstage/core';

const builder = createServiceBuilder(module)
  .addRouter(createRouter())
  .setApiFactory(() => ({
    async appendToFile(data: string) {
      const fs = require('fs');
      const filePath = '/path/to/file.txt';

      fs.appendFileSync(filePath, data);
    },
  }));

export default builder;

In the above code snippet, we import the necessary modules and define a custom action called appendToFile that takes a data parameter. Inside the action, we use fs.appendFileSync to append the provided data to the specified file.

Solution 2: Using fs.createWriteStream

The second solution involves using the fs.createWriteStream method provided by Node.js. This method allows us to create a writable stream to a file, which we can then use to append data. Here’s an example of how you can implement this solution:


import { createRouter } from '@backstage/plugin-router';
import { createServiceBuilder } from '@backstage/core';

const builder = createServiceBuilder(module)
  .addRouter(createRouter())
  .setApiFactory(() => ({
    async appendToFile(data: string) {
      const fs = require('fs');
      const filePath = '/path/to/file.txt';

      const stream = fs.createWriteStream(filePath, { flags: 'a' });
      stream.write(data);
      stream.end();
    },
  }));

export default builder;

In the above code snippet, we import the necessary modules and define a custom action called appendToFile that takes a data parameter. Inside the action, we use fs.createWriteStream to create a writable stream to the specified file with the flags option set to 'a' (append mode). We then write the data to the stream and end it.

With either of the above solutions, you can now use the custom action appendToFile to append data to a file in your Backstage application. Simply call the action and pass the desired data as a parameter.

We hope this blog post has provided you with valuable insights on how to create a custom action in Backstage to append data to a file. Feel free to experiment with both solutions and choose the one that best suits your needs.

Backstage Custom Action to Append file