internet-programming/lab3/node_modules/json-server/lib/server/mixins.js

76 lines
1.9 KiB
JavaScript

"use strict";
const {
nanoid
} = require('nanoid');
const pluralize = require('pluralize');
module.exports = {
getRemovable,
createId,
deepQuery
};
// Returns document ids that have unsatisfied relations
// Example: a comment that references a post that doesn't exist
function getRemovable(db, opts) {
const _ = this;
const removable = [];
_.each(db, (coll, collName) => {
_.each(coll, doc => {
_.each(doc, (value, key) => {
if (new RegExp(`${opts.foreignKeySuffix}$`).test(key)) {
// Remove foreign key suffix and pluralize it
// Example postId -> posts
const refName = pluralize.plural(key.replace(new RegExp(`${opts.foreignKeySuffix}$`), ''));
// Test if table exists
if (db[refName]) {
// Test if references is defined in table
const ref = _.getById(db[refName], value);
if (_.isUndefined(ref)) {
removable.push({
name: collName,
id: doc.id
});
}
}
}
});
});
});
return removable;
}
// Return incremented id or uuid
// Used to override lodash-id's createId with utils.createId
function createId(coll) {
const _ = this;
const idProperty = _.__id();
if (_.isEmpty(coll)) {
return 1;
} else {
let id = _(coll).maxBy(idProperty)[idProperty];
// Increment integer id or generate string id
return _.isFinite(id) ? ++id : nanoid(7);
}
}
function deepQuery(value, q) {
const _ = this;
if (value && q) {
if (_.isArray(value)) {
for (let i = 0; i < value.length; i++) {
if (_.deepQuery(value[i], q)) {
return true;
}
}
} else if (_.isObject(value) && !_.isArray(value)) {
for (const k in value) {
if (_.deepQuery(value[k], q)) {
return true;
}
}
} else if (value.toString().toLowerCase().indexOf(q) !== -1) {
return true;
}
}
}