feat: restructred json/csv into common DateFormat type

makes it easier to generalize other future features over different dataformats

BREAKING CHANGE: exports in package has changed

Author: nutgaard

src/csv.ts src/dataformat/csv.tssrc/csv.ts renamed to src/dataformat/csv.ts

@@ -1,4 +1,5 @@
-import { GeneratorFlow } from './generator-flow';
+import { GeneratorFlow } from '../generator-flow';
+import { DataFormat } from './domain';
 
 type Quote = '"' | "'";
 
@@ -47,6 +48,10 @@ function readCSVLine(chars: string[], startAt: number, delimiter: string = ','):
     return [i + 1, values];
 }
 
+function writeCSVLine(line: Array<string>, delimiter: string = ','): string {
+    return line.map((it) => `"${it.replace(/"/g, '\\"')}"`).join(delimiter);
+}
+
 export function* parseCSV(content: string, delimiter: string = ','): Generator<Array<string>, void> {
     const chars = content.split('');
     let charPointer = 0;
@@ -68,3 +73,22 @@ export function parseCSVToFlow(content: string, delimiter: string = ','): Genera
 export function parseCSVSync(content: string, delimiter: string = ','): Array<string[]> {
     return parseCSVToFlow(content, delimiter).toArray();
 }
+
+export function* writeAsCSV(content: Array<string[]>, delimiter: string = ','): Generator<string, void> {
+    for (const line of content) {
+        yield writeCSVLine(line, delimiter);
+    }
+}
+
+export function writeAsCSVSync(content: Array<string[]>, delimiter: string = ','): string {
+    return new GeneratorFlow<string>(() => writeAsCSV(content, delimiter)).toArray().join('\n');
+}
+
+export const CsvFormat: DataFormat<unknown> = {
+    serialize(object: Array<string[]>, delimiter: string = ','): string {
+        return writeAsCSVSync(object, delimiter);
+    },
+    deserialize(content: string, delimiter: string = ','): Array<string[]> {
+        return parseCSVSync(content, delimiter);
+    }
+};

src/dataformat/domain.ts

@@ -0,0 +1,4 @@
+export interface DataFormat<T> {
+    serialize(object: T): string;
+    deserialize(object: string): T;
+}

src/dataformat/json.ts

@@ -0,0 +1,14 @@
+import { DataFormat } from './domain';
+
+export function serialize(object: unknown): string {
+    return typeof object === 'string' ? object : JSON.stringify(object, null, 2);
+}
+
+export function deserialize<T>(content: string): T {
+    return JSON.parse(content);
+}
+
+export const JsonFormat: DataFormat<unknown> = {
+    serialize,
+    deserialize
+};

src/file.ts

@@ -1,7 +1,7 @@
 import * as fs from 'fs';
 import { WriteStream } from 'fs';
 import * as fsP from 'fs/promises';
-import { serialize, deserialize } from './json';
+import { serialize, deserialize } from './dataformat/json';
 
 export async function read(path: string): Promise<string> {
     return fsP.readFile(path, 'utf8');

src/index.ts

@@ -1,4 +1,4 @@
 export * as File from './file';
-export * as CSV from './csv';
-export * as Json from './json';
+export * as CSV from './dataformat/csv';
+export * as Json from './dataformat/json';
 export { GeneratorFlow } from './generator-flow';

src/json.ts

@@ -1,6 +1,6 @@
 import * as fs from 'fs';
-import { test, assertThat } from './test-lib';
-import { parseCSVSync } from '../src/csv';
+import { test, assertThat } from '../test-lib';
+import { parseCSVSync, CsvFormat } from '../../src/dataformat/csv';
 
 test('should be able to parse super simple csv', () => {
     const csv = parseCSVSync('h1,h2\nv1,v2\nv3,v4');
@@ -42,3 +42,17 @@ test('should be able to parse csv with multilne content', () => {
         'csv content should match'
     );
 });
+
+test('should implement csv dataformat', () => {
+    const data = [
+        ['Header 1', 'Header "2"'],
+        ['value 1', 'value "2"'],
+        ['value 2', "value '2'"],
+        ['value 3', 'value \n"2\n and more']
+    ];
+
+    const textual: string = CsvFormat.serialize(data);
+    const recreated = CsvFormat.deserialize(textual);
+
+    assertThat(data, recreated, 'recreated json is similar to original data');
+});

test/csv.test.ts test/dataformat/csv.test.tstest/csv.test.ts renamed to test/dataformat/csv.test.ts

@@ -1,5 +1,5 @@
-import { test, assertThat } from './test-lib';
-import { serialize, deserialize } from '../src/json';
+import { test, assertThat } from '../test-lib';
+import { serialize, deserialize, JsonFormat } from '../../src/dataformat/json';
 
 test('should not try to serialize string', () => {
     assertThat('hei', serialize('hei'), 'string is the same');
@@ -14,3 +14,11 @@ test('should deserialize json', () => {
     assertThat(['content'], deserialize('[\n  "content"\n]'), 'array is deserialized');
     assertThat({ content: 'hei' }, deserialize('{\n  "content": "hei"\n}'), 'object is deserialized');
 });
+
+test('should implement json dataformat', () => {
+    const data = { content: 'hello', value: { content: 'world' } };
+    const json: string = JsonFormat.serialize(data);
+    const recreated = JsonFormat.deserialize(json);
+
+    assertThat(data, recreated, 'recreated json is similar to original data');
+});

test/json.test.ts test/dataformat/json.test.tstest/json.test.ts renamed to test/dataformat/json.test.ts

@@ -1,2 +1,2 @@
-import './csv.test';
-import './json.test';
+import './dataformat/csv.test';
+import './dataformat/json.test';