Lab: Search API بـ Express

{  "name": "product-search",  "type": "module",  "scripts": { "start": "node src/server.js" },  "dependencies": {    "@elastic/elasticsearch": "^8.17.0",    "express": "^4.21.2"  }}

import { Client } from "@elastic/elasticsearch";export const es = new Client({  node: process.env.ELASTIC_URL ?? "http://localhost:9200",  auth: process.env.ELASTIC_API_KEY    ? { apiKey: process.env.ELASTIC_API_KEY }    : undefined,});

import { es } from "./es.js";const index = "products";const settings = {  analysis: {    char_filter: {      indic_digits: {        type: "mapping",        mappings: ["٠ => 0", "١ => 1", "٢ => 2", "٣ => 3", "٤ => 4", "٥ => 5", "٦ => 6", "٧ => 7", "٨ => 8", "٩ => 9"],      },    },    filter: {      product_synonyms: {        type: "synonym_graph",        synonyms: ["iphone, آيفون, ايفون", "laptop, لابتوب, notebook"],      },    },    analyzer: {      product_text: {        type: "custom",        char_filter: ["indic_digits"],        tokenizer: "standard",        filter: ["lowercase", "arabic_normalization", "product_synonyms"],      },      suggest_text: {        type: "custom",        char_filter: ["indic_digits"],        tokenizer: "standard",        filter: ["lowercase", "arabic_normalization"],      },    },  },};const mappings = {  properties: {    sku: { type: "keyword" },    name: {      type: "text",      analyzer: "product_text",      fields: { suggest: { type: "search_as_you_type", analyzer: "suggest_text" } },    },    description: { type: "text", analyzer: "product_text" },    brand: { type: "keyword" },    category: { type: "keyword" },    price: { type: "float" },    rating: { type: "float" },    stock: { type: "integer" },    ram_gb: { type: "integer" },    storage_gb: { type: "integer" },  },};export async function ensureProductsIndex() {  if (await es.indices.exists({ index })) return;  await es.indices.create({ index, settings, mappings });}

function toNum(value) {  if (value == null || value === "") return null;  const n = Number(value);  return Number.isFinite(n) ? n : null;}function asFilter(clauses) {  const list = clauses.filter(Boolean);  if (list.length === 0) return { match_all: {} };  if (list.length === 1) return list[0];  return { bool: { filter: list } };}function textQuery(q) {  return {    bool: {      should: [        { term: { sku: { value: q.toUpperCase(), boost: 20 } } },        {          multi_match: {            query: q,            fields: ["name^3", "description"],            fuzziness: "AUTO",            prefix_length: 1,          },        },      ],      minimum_should_match: 1,    },  };}export function searchBody(input) {  const q = String(input.q ?? "").trim();  const price = {};  const minPrice = toNum(input.minPrice);  const maxPrice = toNum(input.maxPrice);  if (minPrice != null) price.gte = minPrice;  if (maxPrice != null) price.lte = maxPrice;  const priceFilter = minPrice != null || maxPrice != null ? { range: { price } } : null;  const rating = toNum(input.minRating);  const ratingFilter = rating != null ? { range: { rating: { gte: rating } } } : null;  const stockFilter = input.inStock === "1" ? { range: { stock: { gt: 0 } } } : null;  const ram = toNum(input.ramGb);  const ramFilter = ram != null ? { term: { ram_gb: ram } } : null;  const brandFilter = input.brand ? { term: { brand: String(input.brand) } } : null;  const hitsFilters = [priceFilter, ratingFilter, stockFilter, ramFilter, brandFilter];  const brandCountFilters = [priceFilter, ratingFilter, stockFilter, ramFilter];  return {    query: {      bool: {        must: q ? [textQuery(q)] : [{ match_all: {} }],        filter: hitsFilters.filter(Boolean),      },    },    aggs: {      brands: {        filter: asFilter(brandCountFilters),        aggs: { values: { terms: { field: "brand", size: 20 } } },      },    },    highlight: {      fields: { description: { fragment_size: 140, number_of_fragments: 1 } },      pre_tags: ["<mark>"],      post_tags: ["</mark>"],    },  };}export function suggestBody(prefix) {  return {    size: 8,    _source: ["name"],    query: {      multi_match: {        query: prefix.trim(),        type: "bool_prefix",        fields: ["name.suggest", "name.suggest._2gram", "name.suggest._3gram"],      },    },  };}

import express from "express";import { es } from "./es.js";import { ensureProductsIndex } from "./ensure-index.js";import { searchBody, suggestBody } from "./search.js";const app = express();app.use(express.json());app.get("/search", async (req, res, next) => {  try {    const page = clampInt(req.query.page, 1, 20);    const size = clampInt(req.query.size, 20, 50);    const result = await es.search({      index: "products",      from: (page - 1) * size,      size,      track_total_hits: true,      ...searchBody(req.query),    });    const total = result.hits.total;    res.json({      total: typeof total === "number" ? total : total?.value ?? 0,      totalRelation: typeof total === "number" ? "eq" : total?.relation ?? "eq",      hits: result.hits.hits.map((hit) => ({        id: hit._id,        score: hit._score,        name: hit._source?.name,        brand: hit._source?.brand,        price: hit._source?.price,        highlight: hit.highlight?.description ?? [],      })),      brands: (result.aggregations?.brands?.values?.buckets ?? []).map((b) => ({        key: b.key,        count: b.doc_count,      })),    });  } catch (err) {    next(err);  }});app.get("/suggest", async (req, res, next) => {  try {    const q = String(req.query.q ?? "");    if (q.trim().length < 2) return res.json({ suggestions: [] });    const result = await es.search({ index: "products", ...suggestBody(q) });    res.json({ suggestions: result.hits.hits.map((hit) => hit._source?.name) });  } catch (err) {    next(err);  }});app.post("/products", async (req, res, next) => {  try {    const doc = req.body ?? {};    if (!doc.id || !doc.name) return res.status(400).json({ error: "id_and_name_required" });    await es.index({      index: "products",      id: String(doc.id),      refresh: true,      document: {        sku: String(doc.sku ?? "").toUpperCase(),        name: doc.name,        description: doc.description ?? "",        brand: doc.brand ?? "",        category: doc.category ?? "",        price: Number(doc.price ?? 0),        rating: Number(doc.rating ?? 0),        stock: Number(doc.stock ?? 0),        ram_gb: Number(doc.ram_gb ?? 0),        storage_gb: Number(doc.storage_gb ?? 0),      },    });    res.status(201).json({ id: String(doc.id) });  } catch (err) {    next(err);  }});app.use((err, _req, res, _next) => {  console.error(err);  res.status(503).json({ error: "search_unavailable" });});await ensureProductsIndex();app.listen(3000, () => console.log("search api on :3000"));function clampInt(value, fallback, max) {  const n = Number(value);  if (!Number.isInteger(n) || n < 1) return Math.min(fallback, max);  return Math.min(n, max);}