Show HN: Sir – Git-diff-able JSON database on yer filesystem

All in all this makes the database easy to understand and inspect. As well as making the code easy to read and maintain.

Configure the root directory of your database.

Deletes a table.

Creates a table (if it doesn't exist) and returns it.

Creates a table (if it doesn't exist) that has indexes for the given properties, and returns it.

Adds (or updates) an item to the table by key.

Gets an item from the table by key.

Gets all items from the table.

import path from 'path';
import assert from 'assert';
import fs from 'fs';

import {getTable, getIndexedTable, dropTable, config} from './api.js';

testGetTable();
testGetIndexedTable();
testDropTable();
testPut();
testIndexedPut();
testGet();
testGetAll();

function testGetTable() {
  const root = path.resolve(__dirname, "test-get-table");
  config({root});

  dropTable("users");
  dropTable("subscriptions");

  getTable("users");
  getTable("subscriptions");

  assert.strictEqual(fs.existsSync(path.resolve(root, "users", "tableInfo.json")), true);
  assert.strictEqual(fs.existsSync(path.resolve(root, "subscriptions", "tableInfo.json")), true);

  fs.rmdirSync(root, {recursive:true});
}

function testGetIndexedTable() {
  const root = path.resolve(__dirname, "test-get-indexed-table");
  config({root});

  dropTable("users");
  dropTable("subscriptions");

  getIndexedTable("users", ["username", "email"]);
  getIndexedTable("subscriptions", ["email"]);

  try {
    assert.strictEqual(fs.existsSync(path.resolve(root, "users", "tableInfo.json")), true);
    assert.strictEqual(fs.existsSync(path.resolve(root, "subscriptions", "tableInfo.json")), true);

    assert.strictEqual(fs.existsSync(path.resolve(root, "users", "_indexes", "username", "indexInfo.json")), true);
    assert.strictEqual(fs.existsSync(path.resolve(root, "users", "_indexes", "email", "indexInfo.json")), true);
    assert.strictEqual(fs.existsSync(path.resolve(root, "subscriptions", "_indexes", "email", "indexInfo.json")), true);
  } catch(e) {
    console.error(e);
  }

  fs.rmdirSync(root, {recursive:true});
}

function testDropTable() {
  const root = path.resolve(__dirname, "test-drop-table");
  config({root});

  getTable("users");
  getTable("subscriptions");

  dropTable("users");
  dropTable("subscriptions");

  assert.strictEqual(fs.existsSync(path.resolve(root, "users", "tableInfo.json")), false);
  assert.strictEqual(fs.existsSync(path.resolve(root, "subscriptions", "tableInfo.json")), false);

  fs.rmdirSync(root, {recursive:true});
}

function testPut() {
  const root = path.resolve(__dirname, "test-get-table");
  const errors = [];
  let gotItems;
  let key = 1;

  config({root});

  dropTable("items");

  const Items = getTable("items");
  const items = [
    {
      key: `key${key++}`,
      name: 'Apple',
      type: 'fruit',
      grams: 325
    },
    {
      key: `key${key++}`,
      name: 'Pear',
      type: 'fruit',
      grams: 410
    },
    {
      key: `key${key++}`,
      name: 'Soledado',
      type: 'career',
      grams: null,
      qualities_of_winners: [
        "devisiveness",
        "rationality",
        "aggression",
        "calmness"
      ]
    },
  ];
  
  try {
    items.forEach(item => Items.put(item.key, item));
  } catch(e) {
    errors.push(e);
  }

  assert.strictEqual(errors.length, 0);

  try {
    gotItems = items.map(item => Items.get(item.key));
  } catch(e) {
    errors.push(e);
  }

  assert.strictEqual(errors.length, 0);

  assert.strictEqual(JSON.stringify(items), JSON.stringify(gotItems));

  fs.rmdirSync(root, {recursive:true});
}

function testIndexedPut() {
  const root = path.resolve(__dirname, "test-indexed-put-table");
  const errors = [];
  let gotItems1 = [], gotItems2 = [], gotItems3 = [];
  let key = 1;

  config({root});

  dropTable("items");

  const Items = getIndexedTable("items", ["name", "type"]);
  const items = [
    {
      key: `key${key++}`,
      name: 'Apple',
      type: 'fruit',
      grams: 325
    },
    {
      key: `key${key++}`,
      name: 'Pear',
      type: 'fruit',
      grams: 410
    },
    {
      key: `key${key++}`,
      name: 'Soledado',
      type: 'career',
      grams: null,
      qualities_of_winners: [
        "devisiveness",
        "rationality",
        "aggression",
        "calmness"
      ]
    },
  ];
  
  try {
    try {
      items.forEach(item => Items.put(item.key, item));
    } catch(e) {
      errors.push(e);
    }

    assert.strictEqual(errors.length, 0);

    try {
      gotItems1 = items.map(item => Items.get(item.key));
    } catch(e) {
      errors.push(e);
    }

    assert.strictEqual(errors.length, 0);

    assert.strictEqual(JSON.stringify(items), JSON.stringify(gotItems1));

    try {
      gotItems2 = Items.getAllMatchingRecordsFromIndex('name', 'Apple');
    } catch(e) {
      errors.push(e);
    }

    assert.strictEqual(errors.length, 0);
    assert.strictEqual(gotItems2.length, 1);
    assert.strictEqual(JSON.stringify(items.slice(0,1)), JSON.stringify(gotItems2.map(([,val]) => val)));

    try {
      gotItems3 = Items.getAllMatchingRecordsFromIndex('type', 'fruit');
    } catch(e) {
      errors.push(e);
    }

    assert.strictEqual(errors.length, 0);
    assert.strictEqual(gotItems3.length, 2);
    assert.strictEqual(JSON.stringify(items.slice(0,2)), JSON.stringify(gotItems3.map(([,val]) => val)));

  } catch(e) {
    console.error(e);
    console.log(errors);
  }

  fs.rmdirSync(root, {recursive:true});
}

function testGet() {
  const root = path.resolve(__dirname, "test-get-table");
  const errors = [];
  const gotItems = [];
  let key = 1;

  config({root});

  dropTable("items");

  const Items = getTable("items");
  const items = [
    {
      key: `key${key++}`,
      name: 'Apple',
      type: 'fruit',
      grams: 325
    },
    {
      key: `key${key++}`,
      name: 'Pear',
      type: 'fruit',
      grams: 410
    },
    {
      key: `key${key++}`,
      name: 'Soledado',
      type: 'career',
      grams: null,
      qualities_of_winners: [
        "devisiveness",
        "rationality",
        "aggression",
        "calmness"
      ]
    },
  ];
  
  for( const item of items ) {
    try {
      gotItems.push(Items.get(item.key));
    } catch(e) {
      errors.push(e);
    }
  }

  assert.strictEqual(errors.length, 3);
  assert.strictEqual(gotItems.length, 0);

  fs.rmdirSync(root, {recursive:true});
}

function testGetAll() {
  const root = path.resolve(__dirname, "test-get-table");
  const errors = [];
  let gotItems;
  let key = 1;

  config({root});

  dropTable("items");

  const Items = getTable("items");
  const items = [
    {
      key: `key${key++}`,
      name: 'Apple',
      type: 'fruit',
      grams: 325
    },
    {
      key: `key${key++}`,
      name: 'Pear',
      type: 'fruit',
      grams: 410
    },
    {
      key: `key${key++}`,
      name: 'Soledado',
      type: 'career',
      grams: null,
      qualities_of_winners: [
        "devisiveness",
        "rationality",
        "aggression",
        "calmness"
      ]
    },
  ];
  
  try {
    items.forEach(item => Items.put(item.key, item));
  } catch(e) {
    errors.push(e);
  }

  assert.strictEqual(errors.length, 0);

  try {
    gotItems = Items.getAll();
  } catch(e) {
    errors.push(e);
  }

  assert.strictEqual(errors.length, 0);

  items.sort((a,b) => a.key < b.key ? -1 : 1);
  gotItems.sort((a,b) => a.key < b.key ? -1 : 1);
  assert.strictEqual(JSON.stringify(items), JSON.stringify(gotItems));

  fs.rmdirSync(root, {recursive:true});
}

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