observablehq.com Open in urlscan Pro
2606:4700:10::6816:14dc  Public Scan

Form analysis
0 forms found in the DOM

Text Content

Why Observable
Product
Use cases
Resources
Pricing
SearchSign inSign up

Steve


Fork
Public
Edited
Mar 15
1 Like

Insert cell


Insert cell


Insert cell


Insert cell


Insert cell


Insert cell


Insert cell

doh_nameserver_url = `https://1.1.1.1/dns-query`;



Insert cell

resolver = {
const { DohResolver } = await
require('https://cdn.jsdelivr.net/npm/dohjs@latest/dist/doh.min.js');
return new DohResolver(doh_nameserver_url);
}



Insert cell

queryDnsRecords = async (domainName, recordType = 'A') => {


/* guard against missing inputs */
if (!domainName) throw Error(`No DNS domain name provided: "${domainName}"`);
if (!recordType) throw Error(`No DNS record type provided: "${recordType}"`);


/* run query, catch timeouts/errors */
let res;
try {
res = await resolver.query(domainName, recordType, 'GET', 'Accept:
application/dns-message', 1000);
} catch (err) {
return err;
}


/* trap DNS error response codes */
if (res.rcode !== 'NOERROR') {
switch (res.rcode) {
case 'NXDOMAIN':
throw Error("NXDOMAIN: DNS query failed because the domain name queried does not
exist");
break;
case 'SERVFAIL':
throw Error("SERVFAIL: DNS query failed because the answer cannot be given");
break;
case 'REFUSED':
throw Error("REFUSED: DNS query failed because the server refused to anser due
to policy");
break;
default:
throw Error("DNS query returned an unknown response code");
}
}

return res.answers;
}



Insert cell
Create interactive documents like this one.
Sign up for free
Learn new data visualization techniques. Perform complex data analysis.
Publish your findings in a compelling document. All in the same tool.
Sign up for free
More from Observable creators
View all
Conformal Prediction
Herb Susmann
Apr 18
Pension Calculator 🧓👴 🚧 draft4
Declan Naughton
Apr 25• 1
Πόσο χρονών είσαι, Θεσσαλονίκη;
infographeo
Feb 20• 3
Hello, Plotteus!
Bartosz Prusinowski
Feb 28• 30 2
The logistic bifurcation locus
Mark McClure
Apr 9• 7
How clean is your state’s electricity?
Climate Lab•Harry Stevens
Apr 12• 35
Data Exploration on "Oscar Data" using SQL This notebook is a fork
urvi•URVI JAIN
Mar 14• 3
Spotify Beeswarm Plot 2.0
Tanya Shapiro
Apr 10• 1
Product
 * Integrations
 * Pricing

Resources
 * Customer stories
 * Community
 * Documentation

Company
 * Blog
 * Jobs
 * Newsletter

LinkedInTwitterGitHubYouTube
© 2023 Observable, Inc.PrivacyTerms of Service




Fork

View
Export
Edit
Pin
Add comment
Select
Duplicate
Copy link
Embed
Delete
domainName

Edit
Pin
Add comment
Copy import
Select
Duplicate
Copy link
Embed
Delete
recordTypes

Edit
Pin
Add comment
Copy import
Select
Duplicate
Copy link
Embed
Delete
Edit
Pin
Add comment
Select
Duplicate
Copy link
Embed
Delete
Edit
Pin
Add comment
Select
Duplicate
Copy link
Embed
Delete
Edit
Pin
Add comment
Select
Duplicate
Copy link
Embed
Delete
doh_nameserver_url

Unpin
Add comment
Copy import
Select
Duplicate
Copy link
Embed
Delete
resolver

Unpin
Add comment
Copy import
Select
Duplicate
Copy link
Embed
Delete
queryDnsRecords

Unpin
Add comment
Copy import
Select
Duplicate
Copy link
Embed
Delete



For developers
For spreadsheet users
For SQL users
For data analysts

Explore the community
Integrations
Security
Observable Plot
Customer stories

Try Observable
Pharma
Finance
Technology
Education
Tutorials
Community
Docs
Blog
JavaScript
Markdown
HTML
JavaScript
Markdown
HTML
JavaScript
Markdown
HTML