Page-hash NPM | npm.io

Page Hash

Page Hash API provides hashes of the given item which some URL points to in JSON object. An example is given below:

{
  "load": 314,
  "url": "https://example.com",
  "hashes": [
    {
      "algo": "sha256",
      "hash": "3587cb776ce0e4e8237f215800b7dffba0f25865cb84550e87ea8bbac838c423"
    },
    {
      "algo": "sha1",
      "hash": "0e973b59f476007fd10f87f347c3956065516fc0"
    },
    {
      "algo": "md5",
      "hash": "09b9c392dc1f6e914cea287cb6be34b0"
    }
  ]
}

Running a local version

Install dependencies

npm install

Run

npm start

This will start the app on port 7800. If you'd like to change that, change PORT in app.js.

Using in Node.js

Install using npm

npm install page-hash --save

Documentation

TL;DR

API endpoint: pagehash.muzzammil.xyz/?url=% where % = full URL of resource.
In Node.js, pagehash(STRING) takes URL as input and returns a promise.
Example: curl "https://pagehash.muzzammil.xyz/?url=https://example.com"
Error handling:
- In Node.js, handle promise rejection.
- For other stuff, if(hashes == null) { alert("err"); }

Calling the API

In Node.js, pagehash(STRING)'s promise returns result as an object.

API endpoint: pagehash.muzzammil.xyz/?url=% where % = full URL of resource.

The API will return a JSON object containing one of the keys as hashes which is an array of multiple hashes computed for the given URL. Each element of the array contains the name of the algorithm used in algo and the computed hash in hash.

...
  "hashes": [
    {
      "algo": "sha256",
      "hash": "3587cb776ce0e4e8237f215800b7dffba0f25865cb84550e87ea8bbac838c423"
    },
    {
      "algo": "sha1",
      "hash": "0e973b59f476007fd10f87f347c3956065516fc0"
    },
...

Along with the hashes computed, the returned JSON also contains the URL for which the hash is computed in url and API load time in load.

{
  "load": 314,
  "url": "https://example.com",
...

Examples

-- using cURL

$ curl "https://pagehash.muzzammil.xyz/?url=https://example.com"
{
  "load": 314,
  "url": "https://example.com",
  "hashes": [
    {
      "algo": "sha256",
      "hash": "3587cb776ce0e4e8237f215800b7dffba0f25865cb84550e87ea8bbac838c423"
    },
    {
      "algo": "sha1",
      "hash": "0e973b59f476007fd10f87f347c3956065516fc0"
    },
    {
      "algo": "md5",
      "hash": "09b9c392dc1f6e914cea287cb6be34b0"
    }
  ]
}

-- using Node.js

const pagehash = require("page-hash")

pagehash("https://example.com").then(result => {
  console.log("Result\n", result)
}, error => {
  console.log("Error\n", error)
})

Result
 { url: 'https://example.com',
  hashes:
   [ { algo: 'sha256',
       hash:
        '3587cb776ce0e4e8237f215800b7dffba0f25865cb84550e87ea8bbac838c423' },
     { algo: 'sha1',
       hash: '0e973b59f476007fd10f87f347c3956065516fc0' },
     { algo: 'md5', hash: '09b9c392dc1f6e914cea287cb6be34b0' } ] }

Error handling

In Node.js, handle rejection for returned promise as shown in the example for Node.js.

Like the hashes, error details are also given in JSON object which contains multiple ways to detect errors and what caused them. An example of error response may look like this:

{
  "url": "https://example.co",
  "hashes": null,
  "errno": "ENOTFOUND",
  "code": "ENOTFOUND",
  "syscall": "getaddrinfo",
  "hostname": "example.co",
  "host": "example.co",
  "port": 443
}

The above error occured because there is no https://example.co, yet, and the API failed to get any response from this URL.

Error detection

TL;DR -- Short checking, if(hashes == null) { alert("err"); }

I appended the error returned by request in node.js so I can't guarantee what it will return. But, I turned hashes to null in case of any error. So, if you don't want to dig deep, just check if hashes is null or not. If it is, it means that error has occurred somewhere. However, if you want to dig deep, for some reason, make sure errno and other keys exist before reading them to avoid any further failure.

Contributions

Contributions are welcome but please don't make Pull Requests for typos, grammatical mistakes, "sane way" of doing it, etc. Open an issue for it. Thanks!