feat: implement getFileById method

tests/File.spec.ts

@@ -0,0 +1,62 @@
+import { File } from '../src/models/File';
+import { expect } from 'chai';
+import { Readable } from 'stream';
+
+describe('File', function () {
+  it('should be defined', function () {
+    expect(File).to.not.be.undefined;
+  });
+
+  it('should have a constructor', function () {
+    expect(File).to.have.property('constructor');
+  });
+
+  it('should have a stream property', function () {
+    expect(
+      new File(new Readable(), 'File Name', 'Content Type', 1)
+    ).to.have.property('stream');
+  });
+
+  it('should have a fileName property', function () {
+    expect(
+      new File(new Readable(), 'File Name', 'Content Type', 1)
+    ).to.have.property('fileName');
+  });
+
+  it('should have a contentType property', function () {
+    expect(
+      new File(new Readable(), 'File Name', 'Content Type', 1)
+    ).to.have.property('contentType');
+  });
+
+  it('should have a contentLength property', function () {
+    expect(
+      new File(new Readable(), 'File Name', 'Content Type', 1)
+    ).to.have.property('contentLength');
+  });
+
+  it('should have a constructor that sets the stream property', function () {
+    const stream = new Readable();
+    expect(
+      new File(stream, 'File Name', 'Content Type', 1).stream
+    ).to.deep.equal(stream);
+  });
+
+  it('should have a constructor that sets the fileName property', function () {
+    expect(
+      new File(new Readable(), 'File Name', 'Content Type', 1).fileName
+    ).to.equal('File Name');
+  });
+
+  it('should have a constructor that sets the contentType property', function () {
+    expect(
+      new File(new Readable(), 'File Name', 'Content Type', 1).contentType
+    ).to.equal('Content Type');
+  });
+
+  it('should have a constructor that sets the contentLength property', function () {
+    expect(
+      new File(new Readable(), 'File Name', 'Content Type', 1).contentLength
+    ).to.equal(1);
+  });
+});