Nginx log parser and Prometheus exporter

This service parses incoming syslog messages from Nginx sent over UDP and converts them into Prometheus metrics exported through the built-in HTTP server.

• If the prefix-list is specified then per-URI statistics are generated. Using this feature without URI-prefix list is dangerous because it leads to an unbounded memory usage. It's therefore enabled only with a limited prefix list.

  The URI prefix list is a plain-text file with a single prefix per line, e.g. /api/call1.json /api/call2.json /api/call3.json ...

  URIs received from nginx are stripped of any query parameters - only the part before '?' is used.

• It optionally supports country lookup for client IPs using MaxMind GeoIP database.

Nginx configuration snippet

log_format collector '$remote_addr|$scheme|$host|$request_method|$server_protocol|$request_uri|$status|$request_time|$request_length|$bytes_sent';
access_log syslog:server=1.1.1.1:1514,tag=nginx collector;

Getting it

• Get binary directly from releases, only linux-amd64 build currently available:

• Simple build, with latest versions of all dependencies: go get github.com/blind-oracle/nginx-prometheus

• Repoducible build, using dep to get pinned dependencies: Get dep binary, e.g.: go get -u github.com/golang/dep/cmd/dep

  go get github.com/blind-oracle/nginx-prometheus cd $GOPATH/src/github.com/blind-oracle/nginx-prometheus $GOPATH/bin/dep ensure go build

Usage example

# ./nginx-prometheus \
 -debug false \
 -listenSyslog 0.0.0.0:1514 \
 -listenHTTP 0.0.0.0:1514 \
 -geoipCountryDB /etc/nginx-prometheus/country.mmdb \
 -uriPrefixFile /etc/nginx-prometheus/uriPrefixes.txt

• debug - prints every syslog message received if true (defaults to false)
• listenSyslog - ip:port on which to listen for UDP Syslog messages (defaults to 0.0.0.0:1514)
• listenHTTP - ip:port on which to listen for incoming HTTP requests from Prometheus (defaults to 0.0.0.0:11080)
• geoipCountryDB - path to MaxMind country GeoIP database (optional)
• uriPrefixFile - path to a URI prefix list (optional)

Grafana dashboard

Add Prometheus source to Grafana and import grafana-dashboard.json for most common graphs.