Examples and demos on how developers can use get their work done in Observable

Ian Johnson

Monitor the status of your HTTP services with a condensed view of Amazon Web Services CloudWatch Logs.

Observable

AWS HTTP Status Dashboard

Toph Tucker

How long are your GitHub Actions integration tests taking to run?

Integration Test Duration

Flaky tests waste engineer time; which GitHub Actions jobs fail and then pass when re-run?

Integration Test Flakiness

AWS S3 API Starter

Manage virtual machines with the Amazon EC2 API

AWS EC2 API Starter

Anjana Vakil

Visualizing Open-Source Code, Contributions & Communities

Mike Bostock

Most Popular Programming Languages, 2004–2021

Database Outage Plot

Lauren Buchman

DataViz Dashboards for Developers

Video - How Data Visualization Affects Developer Practices

Melody Meckfessel

For the foreseeable future, people (or "developers") are writing the world's software. In 2020, there were ~56M+ developers on Github with a predicted 100M+ by 2025 (almost doubling in 5 years!!). Many more people are writing software than ever before.

“Yes And”: Collaboration for software developers

Hierarchical edge bundling II

Notebook visualizer

Zoomable sunburst

Scott King

Mobile App Breaches, Data Leaks, and Malware Timeline

Tom Larkworthy

Chat application with Firebase on Observable (Twitch)

Mobile Games Data Visualization

Endpoint Services

How to make a Twitter BlueSky Bot

Soundcloud Reactive Audio Visualizer Music Video Generator

3D apps overview

Query, Process and Visualize Data Stream via a Functional Pipeline approach

Abe Yang

Bright Sky (Better Weather App)

Nikhil Thorat

How to build a Teachable Machine with TensorFlow.js

Ridiculously Rapid Software-as-a-Service (SaaS) development with Observable, Firebase and Stripe

Collections related to specific areas of interest, curated by the Observable team. 

Topics

Observable for Developers

I think I am seeing the observable dataflow fire twice when I listen to a document that includes a FieldValue.serverTimestamp().  Is that possible / expected?

David Kirkby

I believe this is expected behaviour, the local cache will see two values, the pre sync estimated time, then the post sync actual server time.

https://github.com/firebase/firebase-js-sdk/issues/2461

Thanks!  I don't really need timestamps and was just using them to be notified (via listen) when a new document is added to a specific collection, following your example here.  Is there a simpler pattern for achieving that, which behaves the same whether the new doc is added locally or remotely?

here the timestamp is a field, so if you don't need it don't write it. Are you requiring ordering as well? If you do require ordering you could use local timestamp, but thats sometimes a problem. If you need to use server timestamps, you can look at the pendingWrites meta property and filter there? https://stackoverflow.com/questions/49972173/firestore-onsnapshot-executing-twice

If you add the pendingWrites filter as an option to "listen" I would merge it.

I just added an ignorePendingWrites option on my fork and tested that it fixes this issue.

However, I suspect I am approaching my design the wrong way if these implementation subtleties are breaking it.  I just want an observable cell that watches a specific collection and has the value of the newest document added.  I am only use a timestamp as a means to achieve this end, since I could find any other way to query for the most recently added document.

I guess a different pattern I could use it to write two docs with the same content, once as a new document and once with a predefined name, then listen to the predefined name, i.e.

db.collection("C").add(content);
db.collection("C").doc("latest").set(content);

newest = listen(db.collection("C").doc("latest"))

Oh right, if you want just a single latest, overwrite a common document. If you need to keep the history, each update is a new doc in a collection. If you need to track the 'latest', even when using the history, issue a realtime query that is ordered by timestamp, with a limit of 1 documents. You can "listen" to a query too

listen(db.collection("C").orderBy("timestamp").limit(3))

you can orderBy DESC too I think. It requires additional indexes but it will tell you how to add those if you look at the errors

see
https://firebase.google.com/docs/firestore/query-data/order-limit-data#web-version-8

Purpose-built for displays of data