The Logger provides a system-wide, common way to record log messages. The log messages are stored in Elasticsearch. This is done though an HTTP API.

Before building and running the pz-logger project, please ensure that the following components are available and/or installed, as necessary:

• Git (for checking out repository source)
• Go v1.7 or later
• Glide
• ElasticSearch

For additional details on prerequisites, please refer to the Piazza Developer's Guide repository content for Core Overview or Piazza Logger sections. Also refer to the prerequisites for using Piazza section for additional details.

Create the directory the repository must live in:

$ mkdir -p $GOPATH/src/github.com/venicegeo
$ cd $GOPATH/src/github.com/venicegeo
$ git clone git@github.com:venicegeo/pz-logger.git
$ cd pz-logger

Set up Go environment variables

To function right, Go must have some environment variables set. Run the go env command to list all relevant environment variables. The two most important variables to look for are GOROOT and GOPATH.

• GOROOT must point to the base directory at which Go is installed
• GOPATH must point to a directory that is to serve as your development environment. This is where this code and dependencies will live.

To quickly verify these variables are set, run the command from terminal:

$ go env | egrep "GOPATH|GOROOT"

In order for pz-logger to successfully start it needs access to running, local ElasticSearch instance. If not currently available, it can be downloaded and documentation can be found here. Additionally, the environment variable LOGGER_INDEX must be set; the value of this will be the name of the index in ElasticSearch containing logs.

This project manages dependencies by populating a vendor/ directory using the glide tool. If the tool is already installed, in the code repository, run:

$ glide install -v

This will retrieve all the relevant dependencies at their appropriate versions and place them in vendor/, which enables Go to use those versions in building rather than the default (which is the newest revision in Github).

Adding new dependencies. When adding new dependencies, simply installing them with go get <package> will fetch their latest version and place it in $GOPATH/src. This is undesirable, since it is not repeatable for others. Instead, to add a dependency, use glide get <package>, which will place it in vendor/ and update glide.yaml and glide.lock to remember its version.

To build pz-logger, run go install from the project directory. To build it from elsewhere, run:

$ go install github.com/venicegeo/pz-logger

This will build and place a statically-linked Go executable at $GOPATH/bin/pz-logger.

$ go build
$ ./pz-logger

To run pz-logger, unit tests, run the command shown below. This will run the unit tests for pz-logger and all its subpackages and print coverage summaries.

$ go test -cover github.com/venicegeo/pz-logger/logger

An example response should look similar to

ok  	github.com/venicegeo/pz-logger/logger	4.064s	coverage: 76.8% of statements