prometheus/README.md

Prometheus

Bedecke deinen Himmel, Zeus! A new kid is in town.

Prometheus is a generic time series collection and computation server that is useful in the following fields:

• Industrial Experimentation / Real-Time Behavioral Validation / Software Release Qualification
• Econometric and Natural Sciences
• Operational Concerns and Monitoring

The system is designed to collect telemetry from named targets on given intervals, evaluate rule expressions, display the results, and trigger an action if some condition is observed to be true.

Prerequisites

If you read below in the Getting Started section, the build infrastructure will take care of the following things for you in most cases:

1. Go 1.1.
2. GVM: https://github.com/moovweb/gvm is highly recommended as well.
3. LevelDB: https://code.google.com/p/leveldb/.
4. Protocol Buffers Compiler: http://code.google.com/p/protobuf/.
5. goprotobuf: the code generator and runtime library: http://code.google.com/p/goprotobuf/.
6. Levigo, a Go-wrapper around LevelDB's C library: https://github.com/jmhodges/levigo.
7. GoRest, a RESTful style web-services framework: http://code.google.com/p/gorest/.
8. Prometheus Client, Prometheus in Prometheus https://github.com/prometheus/client_golang.
9. Snappy, a compression library for LevelDB and Levigo http://code.google.com/p/snappy/.

Getting Started

For basic help how to get started:

• The source code is periodically indexed: Prometheus Core.
• For UNIX-like environment users users, please consult the Travis CI configuration in .travis.yml and Makefile.
• All of the core developers are accessible via the Prometheus Developers Mailinglist.

Working with GVM

Starting out, the following workflow is advised:

$ gvm install go1.1
$ gvm use go1.1
$ gvm pkgset create prometheus
$ gvm pkgset use prometheus

This is mainly due to the fact that it allows the user to partition the compile-time side-effects from the rest of one's work environment, particularly ${GOPATH}.

Read below in the General section.

Not Using GVM

It is entirely possible to build Prometheus without gvm. I presently do not advise taking this route due to build environment pollution both against Prometheus and from its build infrastructure onto the system---namely ${GOPATH}.

If you really want to avoid GVM, execute the following:

$ touch build/gvm-stamp

Read below in the General section.

General

For first time users, simply run the following:

$ make

If you run into problems, try the following:

$ SILENCE_THIRD_PARTY_BUILDS=false make

Upon having a satisfactory build, it's possible to create an artifact for end-user distribution:

$ make package
$ find build/package

build/package will be sufficient for whatever archiving mechanism you choose. The important thing to note is that Go presently does not staticly link against C dependency libraries, so including the lib directory is paramount. Providing LD_LIBRARY_PATH or DYLD_LIBRARY_PATH in a scaffolding shell script is advised.

Executing the following target will start up Prometheus for lazy users:

$ ARGUMENTS="-foo -bar -baz" make run

${ARGUMENTS} is passed verbatim into the makefile and thusly Prometheus as $(ARGUMENTS). This is useful for quick one-off invocations and smoke testing.

Problems

If at any point you run into an error with the make build system in terms of its not properly scaffolding things on a given environment, please file a bug or open a pull request with your changes if you can fix it yourself.

Please note that we're explicitly shooting for stable runtime environments and not the latest-whiz bang releases; thusly, we ask you to provide ample architecture and release identification remarks for us.

Testing

$ make test

Packaging

$ make package

Race Detector

Go 1.1 includes a race detector which can be enabled at build time. Here's how to use it with prometheus (assumes that you've already run a successful build).

To run the tests with race detection:

$ GORACE="log_path=/tmp/foo" go test -race ./...

To run the server with race detection:

$ go build -race .
$ GORACE="log_path=/tmp/foo" ./prometheus

Contributing

1. To start, reach out via our mailing list (mentioned above) and ask us what the current priorities are. We can find a good isolated starter project for you.

2. Keeping code hygiene is important. We thusly have a practical preference for the following:

   1. Run make format to ensure the correctness of the Go code's layout.

   2. Run make advice to find facial errors with a static analyzer.

   3. Try to capture your changes in some form of a test. Go makes it easy to write Table Driven Tests. There is no mandate to use this said scaffolding mechanism, but it can make your life easier in the right circumstances.

3. Welcome aboard!

License

Apache License 2.0