feat: decompose with compound keys (e934444a) · Commits · Dian Fay / massive-js

lib/util/decompose.js

+10 −7

Changes for lib/util/decompose.js: 10 added lines, 7 removed lines.
Original line number	Diff line number	Diff line
		'use strict';

		const _ = require('lodash');
		const murmurhash = require('murmurhash').v3;

		/**
		* Collapses tabular result sets into a hierarchical object graph based on the
		@@ -31,6 +32,7 @@ exports = module.exports = function (schema, data) {
		return [];
		}

		schema.pk = _.castArray(schema.pk);
		data = _.castArray(data);

		/* Generate a nested dictionary of id:entity in the form of the final
		@@ -41,19 +43,20 @@ exports = module.exports = function (schema, data) {
		* Output: {1: {id: 1, name: 'hi', children: {111: {id: 111, name: 'ih'}}}
		*/
		const mapping = data.reduce(function (acc, row) {
		if (row[schema.pk] === null) {
		if (schema.pk.every(c => row[c] === null)) {
		throw new Error('Attempted to decompose a row where the root object has a null PK. This can happen if tables in your SELECT list share column names. Ensure that all columns are aliased uniquely and update your decomposition schema if necessary.');
		}

		return (function build (obj, objSchema) {
		const id = row[objSchema.pk];
		objSchema.pk = _.castArray(objSchema.pk);

		// Use a string id instead of the (potentially numerical) row id as keys
		// in the mapping. This prevents Object.keys from reordering the
		// mapping in the "transform" step.
		const strid = '_' + id;
		const id = _.pick(row, objSchema.pk);

		if (id === null) {
		// Add a prefix to ensure strid doesn't get treated as a number, which
		// could lead to Object.keys reordering the mapping in the transform step
		const strid = '_' + murmurhash(JSON.stringify(id));

		if (_.every(id, v => v === null)) {
		// null id means this entity doesn't exist (eg outer join)
		return undefined;
		} else if (!Object.prototype.hasOwnProperty.call(obj, strid)) {

package-lock.json

+5 −0

Changes for package-lock.json: 5 added lines, 0 removed lines.
Original line number	Diff line number	Diff line
		@@ -2578,6 +2578,11 @@
		"integrity": "sha512-tgp+dl5cGk28utYktBsrFqA7HKgrhgPsg6Z/EfhWI4gl1Hwq8B/GmY/0oXZ6nF8hDVesS/FpnYaD/kOWhYQvyg==",
		"dev": true
		},
		"murmurhash": {
		"version": "0.0.2",
		"resolved": "https://registry.npmjs.org/murmurhash/-/murmurhash-0.0.2.tgz",
		"integrity": "sha1-bwe9ihEF5wnCb8iUIMtZMMJFhf4="
		},
		"mute-stream": {
		"version": "0.0.7",
		"resolved": "https://registry.npmjs.org/mute-stream/-/mute-stream-0.0.7.tgz",

package.json

+2 −1

Changes for package.json: 2 added lines, 1 removed line.
Original line number	Diff line number	Diff line
		@@ -52,7 +52,8 @@
		"commander": "2.20.0",
		"glob": "7.1.4",
		"lodash": "4.17.15",
		"pg-promise": "8.7.5",
		"murmurhash": "0.0.2",
		"pg-promise": "8.7.4",
		"pg-query-stream": "2.0.0"
		},
		"devDependencies": {

test/util/decompose.js

+33 −8

Changes for test/util/decompose.js: 33 added lines, 8 removed lines.
Original line number	Diff line number	Diff line
		@@ -27,7 +27,7 @@ describe('decompose', function () {
		}, [
		{parent_id: 1, parent_val: 'p1', children_id: 11, children_val: 'c1'},
		{parent_id: null, parent_val: null, children_id: null, children_val: null}
		]));
		]), 'Attempted to decompose a row where the root object has a null PK. This can happen if tables in your SELECT list share column names. Ensure that all columns are aliased uniquely and update your decomposition schema if necessary.');
		});

		it('should collapse simple tree structures', function () {
		@@ -445,8 +445,8 @@ describe('decompose', function () {
		}]);
		});

		it.skip('should accept and use pk arrays', function () {
		const data = decompose({
		it('should throw if a row is encountered where all pk fields are null', function () {
		assert.throws(() => decompose({
		pk: ['parent_id_one', 'parent_id_two'],
		columns: {parent_id_one: 'id_one', parent_id_two: 'id_two', parent_val: 'val'},
		children1: {
		@@ -459,8 +459,34 @@ describe('decompose', function () {
		array: true
		}
		}
		}, [
		{
		}, [{
		parent_id_one: null,
		parent_id_two: null,
		parent_val: 'p1',
		children1_id_one: 11,
		children1_id_two: 12,
		children1_val: 'c1',
		children1_children2_id_one: 21,
		children1_children2_id_two: 22,
		children1_children2_val: 'd1'
		}]), 'Attempted to decompose a row where the root object has a null PK. This can happen if tables in your SELECT list share column names. Ensure that all columns are aliased uniquely and update your decomposition schema if necessary.');
		});

		it('should accept and use pk arrays', function () {
		const data = decompose({
		pk: ['parent_id_one', 'parent_id_two'],
		columns: {parent_id_one: 'id_one', parent_id_two: 'id_two', parent_val: 'val'},
		children1: {
		pk: ['children1_id_one', 'children1_id_two'],
		columns: {children1_id_one: 'id_one', children1_id_two: 'id_two', children1_val: 'val'},
		array: true,
		children2: {
		pk: ['children1_children2_id_one', 'children1_children2_id_two'],
		columns: {children1_children2_id_one: 'id_one', children1_children2_id_two: 'id_two', children1_children2_val: 'val'},
		array: true
		}
		}
		}, [{
		parent_id_one: 1,
		parent_id_two: 2,
		parent_val: 'p1',
		@@ -500,8 +526,7 @@ describe('decompose', function () {
		children1_children2_id_one: 27,
		children1_children2_id_two: 28,
		children1_children2_val: 'd4'
		}
		]);
		}]);

		assert.deepEqual(data, [{
		id_one: 1,
		@@ -529,7 +554,7 @@ describe('decompose', function () {
		id_one: 15,
		id_two: 16,
		val: 'c3',
		children2: [{id_one: 26, id_two: 28, val: 'd4'}]
		children2: [{id_one: 27, id_two: 28, val: 'd4'}]
		}]
		}]);
		});