Development
The exporter is a Go program using the Prometheus SDK.
External contributions are welcome, see CONTRIBUTING for details.
The exporter initialization is as follows:
- Parse flags options and configuration properties
- Load the default toml file (
default-metrics.toml
) and store each metric in aMetric
struct - Load the custom toml file (if a custom toml file is given)
- Create an
Exporter
object - Register exporter in prometheus library
- Launching a web server to handle incoming requests
- Attempt connection to any configured Oracle Database servers
These operations are mainly done in the main
function.
After this initialization phase, the exporter will wait for the arrival of a request.
Each time, it will iterate over the content of the metricsToScrape
structure (in the function scrape func (e * Export) scrape (ch chan <- prometheus.Metric)
).
For each element (of Metric
type), a call to the ScrapeMetric
function will be made which will itself make a call to the ScrapeGenericValues
function.
The ScrapeGenericValues
function will read the information from the Metric
structure and, depending on the parameters, will generate the metrics to return. In particular, it will use the GeneratePrometheusMetrics
function which will make SQL calls to the database.
Docker/container build
To build a container image, run the following command:
make docker
For ARM:
make docker-arm
Building Binaries
Run build:
make go-build
This will create binaries and archives inside the dist
folder for the building operating system.