etag-cache-leveldb

etag cache based on leveldb

example

import levelup from "levelup";
import leveldown from "leveldown";
import { ETagCacheLevelDB } from "etag-cache-leveldb";

const someDirectory = "/tmp";
const db = await levelup(leveldown(someDirectory));
const cache = new ETagCacheLevelDB(db);

const url = "https://api.github.com/";

const response = await fetch(url);

await cache.storeResponse(response);

// later

const headers = {};

await cache.addHeaders(url, headers); // fill in etag header

const responseWithETag = await fetch(url, { headers });
const cachedResponse = await cache.loadResponse(responseWithETag);

API

Table of Contents

• ETagCacheLevelDB
  • Parameters
  • addHeaders
    • Parameters
  • statistics
  • storeResponse
    • Parameters
  • loadResponse
    • Parameters
• rawTagData
  • Parameters

ETagCacheLevelDB

Stores etags and bodies into leveldb. Reconstructs response with body if etag or url matches. Will store in the cache: url : etag etag : body

Parameters

• db

addHeaders

Adds the "If-None-Match" header if etag is found for the url.

Parameters

• url (string | URL)
• headers Object

Returns Promise<boolean> true if etag was found in cache and header has been added

statistics

Deliver statisics data.

Returns Object

storeResponse

Stores response in the cache. Two entries are stored:

• url : etag
• etag : body

Parameters

• response Response as produced by fetch

Returns Promise<any>

loadResponse

Constructs a new Response feed from the cache if a matching etag is found in the cache.

Parameters

• response Response as provided by fetch

Returns Promise<Response>

rawTagData

Strips away etag flags (weak and the like)

Parameters

• etag (string | null)

Returns (string | undefined) raw etag