Apache Flink Web Dashboard

The web dashboard is work in progress towards the new Flink runtime monitor. In particular, it will provide the following missing features of the current web dashboard:

Live progress monitoring (via live accumulators)
A graph view of the program, as it is executed.
A REST style API to access the status of individual jobs.
A more modular design

The web dashboard can be activated by adding/uncommenting the config parameter jobmanager.new-web-frontend: true in the conf/fink-conf.yaml file. The dashboard listens at http://localhost:8081.

The new web dashboard is work in progress. It starts an additional HTTP server (by default at port 8081) that serves the new web pages and additional background requests. It also relies on the old HTTP server for some requests still.

NOTE: Many values are placeholders still.

Server Backend

The server side of the dashboard is implemented using Netty with Netty Router for REST paths. The framework has very lightweight dependencies.

The code is regular Java code built via Maven. To add additional request handlers, follow the example of the org.apache.flink.runtime.webmonitor.handlers.JobSummaryHandler.

Dashboard Frontend

The web dashboard is implemented using angular.js. The dashboard build infrastructure uses node.js. The dashboard files are all pre-built, so one can try it out without building it.

Preparing the Build Environment

Depending on your version of Linux or MacOS, you may need to manually install node.js and bower.

Ubuntu Linux

Install node.js by following these instructions.

Verify that the installed version is at least 2.11.3, via npm -version.

Install bower via

sudo npm install -g bower

Verify that the installed version is at least 1.4.1, via bower -version.

Install gulp via

sudo npm install -g gulp

Verify that the installed version is at least 3.9.0, via gulp -version.

Building

The build process downloads all requires libraries via the node.js package management tool (npm) and the bower dependency management tool. The final build tool is gulp.

cd flink-runtime-web/web-dashboard
npm install
bower install
gulp

The dashboard code is under /app. The result of the build process is under /web.

When building Flink with Maven (in particular the flink-dist project), the generated files are copied into the build target, to the folder resources/web-runtime-monitor.

Developing

When developing the dashboard, every change needs to recompile the files and update the server:

cd flink-runtime-web/web-dashboard
gulp
cd ../../flink-dist
mvn -DskipTests clean package

To simplify continuous development, one can use a standalone proxy server, together with automatic re-compilation:

Edit the file app/scripts/index.coffee. Comment/uncomment the lines that define the webServer, jobServer, and newServer URLs.
Re-compile the files via gulp. By calling gulp watch, the build-tool autocompiles future changes.
Start the proxy server via node server.js
Access the dashboard at http://localhost:3000