To know whether a project is popular, checking contributor, longevity and ecosystem is enough.

How to evaluate the sustainability of an open source project

Code activity

• Number of commit does not mean everything
  • New project have more commits, stable project have less commits
• Steady increase of contributor is a good sign
  • It is very good if a stable project can pick up developers

Release history

• Every project have their pattern, no generalized rules
• If there are new feature but no release, there may be some issue inside the team

User community

• Check Google Trends to see how popular is the project
• Check project issue checker
  • Healthy project should have a good number of issue
  • Less issue opened may means there is less user

Longevity

Project survive long enough to weather several technology replacement cycles is a good indication.
New project is difficult to judge.

Ecosystem

Need to consider the companies engage with the project. Also software, documentation, articled bundled with the project