function _M.http_init()

in apisix/plugins/prometheus/exporter.lua [112:210]

• 66 lines of code
• 6 McCabe index (conditional complexity)

function _M.http_init(prometheus_enabled_in_stream)
    
    
    if ngx.get_phase() ~= "init" and ngx.get_phase() ~= "init_worker"  then
        if prometheus_bkp then
            prometheus = prometheus_bkp
        end
        return
    end

    clear_tab(metrics)

    
    
    
    
    
    
    

    
    local metric_prefix = "apisix_"
    local attr = plugin.plugin_attr("prometheus")
    if attr and attr.metric_prefix then
        metric_prefix = attr.metric_prefix
    end

    local status_metrics_exptime = core.table.try_read_attr(attr, "metrics",
                                   "http_status", "expire")
    local latency_metrics_exptime = core.table.try_read_attr(attr, "metrics",
                                   "http_latency", "expire")
    local bandwidth_metrics_exptime = core.table.try_read_attr(attr, "metrics",
                                   "bandwidth", "expire")
    local upstream_status_exptime = core.table.try_read_attr(attr, "metrics",
                                   "upstream_status", "expire")

    prometheus = base_prometheus.init("prometheus-metrics", metric_prefix)

    metrics.connections = prometheus:gauge("nginx_http_current_connections",
            "Number of HTTP connections",
            {"state"})

    metrics.requests = prometheus:gauge("http_requests_total",
            "The total number of client requests since APISIX started")

    metrics.etcd_reachable = prometheus:gauge("etcd_reachable",
            "Config server etcd reachable from APISIX, 0 is unreachable")

    metrics.node_info = prometheus:gauge("node_info",
            "Info of APISIX node",
            {"hostname"})

    metrics.etcd_modify_indexes = prometheus:gauge("etcd_modify_indexes",
            "Etcd modify index for APISIX keys",
            {"key"})

    metrics.shared_dict_capacity_bytes = prometheus:gauge("shared_dict_capacity_bytes",
            "The capacity of each nginx shared DICT since APISIX start",
            {"name"})

    metrics.shared_dict_free_space_bytes = prometheus:gauge("shared_dict_free_space_bytes",
            "The free space of each nginx shared DICT since APISIX start",
            {"name"})

    metrics.upstream_status = prometheus:gauge("upstream_status",
            "Upstream status from health check",
            {"name", "ip", "port"},
            upstream_status_exptime)

    

    
    
    
    metrics.status = prometheus:counter("http_status",
            "HTTP status codes per service in APISIX",
            {"code", "route", "matched_uri", "matched_host", "service", "consumer", "node",
            unpack(extra_labels("http_status"))},
            status_metrics_exptime)

    local buckets = DEFAULT_BUCKETS
    if attr and attr.default_buckets then
        buckets = attr.default_buckets
    end

    metrics.latency = prometheus:histogram("http_latency",
        "HTTP request latency in milliseconds per service in APISIX",
        {"type", "route", "service", "consumer", "node", unpack(extra_labels("http_latency"))},
        buckets, latency_metrics_exptime)

    metrics.bandwidth = prometheus:counter("bandwidth",
            "Total bandwidth in bytes consumed per service in APISIX",
            {"type", "route", "service", "consumer", "node", unpack(extra_labels("bandwidth"))},
            bandwidth_metrics_exptime)

    if prometheus_enabled_in_stream then
        init_stream_metrics()
    end
end