parse-prometheus-text-format

A module that parses the Prometheus text format. The output aims to be compatible with that of prom2json. The code for parsing individual samples was ported from the Prometheus Python Client.

Installation

npm install --save parse-prometheus-text-format

Usage

import fs from 'fs';
import parsePrometheusTextFormat from 'parse-prometheus-text-format';

const metricsStr = fs.readFileSync('metrics.txt', 'utf8');
const parsed = parsePrometheusTextFormat(metricsStr);

Example

Input:

# HELP jvm_classes_loaded The number of classes that are currently loaded in the JVM
# TYPE jvm_classes_loaded gauge
jvm_classes_loaded 3851.0

# HELP http_requests_total The total number of HTTP requests.
# TYPE http_requests_total counter
http_requests_total{method="post",code="200"} 1027 1395066363000
http_requests_total{method="post",code="400"}    3 1395066363000

# Escaping in label values:
msdos_file_access_time_seconds{path="C:\\DIR\\FILE.TXT",error="Cannot find file:\n\"FILE.TXT\""} 1.458255915e9

# Minimalistic line:
metric_without_timestamp_and_labels 12.47

# A weird metric from before the epoch:
something_weird{problem="division by zero"} +Inf -3982045

# A histogram, which has a pretty complex representation in the text format:
# HELP http_request_duration_seconds A histogram of the request duration.
# TYPE http_request_duration_seconds histogram
http_request_duration_seconds_bucket{le="0.05"} 24054
http_request_duration_seconds_bucket{le="0.1"} 33444
http_request_duration_seconds_bucket{le="0.2"} 100392
http_request_duration_seconds_bucket{le="0.5"} 129389
http_request_duration_seconds_bucket{le="1"} 133988
http_request_duration_seconds_bucket{le="+Inf"} 144320
http_request_duration_seconds_sum 53423
http_request_duration_seconds_count 144320

# Finally a summary, which has a complex representation, too:
# HELP rpc_duration_seconds A summary of the RPC duration in seconds.
# TYPE rpc_duration_seconds summary
rpc_duration_seconds{quantile="0.01"} 3102
rpc_duration_seconds{quantile="0.05"} 3272
rpc_duration_seconds{quantile="0.5"} 4773
rpc_duration_seconds{quantile="0.9"} 9001
rpc_duration_seconds{quantile="0.99"} 76656
rpc_duration_seconds_sum 1.7560473e+07
rpc_duration_seconds_count 2693

# HELP jvm_gc_collection_seconds Time spent in a given JVM garbage collector in seconds.
# TYPE jvm_gc_collection_seconds summary
jvm_gc_collection_seconds_count{gc="Copy",} 104.0
jvm_gc_collection_seconds_sum{gc="Copy",} 0.491
jvm_gc_collection_seconds_count{gc="MarkSweepCompact",} 12.0
jvm_gc_collection_seconds_sum{gc="MarkSweepCompact",} 0.486

Stringified result:

[
    {
        "name": "jvm_classes_loaded",
        "help": "The number of classes that are currently loaded in the JVM",
        "type": "GAUGE",
        "metrics": [
            {
                "value": "3851.0"
            }
        ]
    },
    {
        "name": "http_requests_total",
        "help": "The total number of HTTP requests.",
        "type": "COUNTER",
        "metrics": [
            {
                "value": "1027",
                "labels": {
                    "method": "post",
                    "code": "200"
                }
            },
            {
                "value": "3",
                "labels": {
                    "method": "post",
                    "code": "400"
                }
            }
        ]
    },
    {
        "name": "msdos_file_access_time_seconds",
        "help": "",
        "type": "UNTYPED",
        "metrics": [
            {
                "value": "1.458255915e9",
                "labels": {
                    "path": "C:\\DIR\\FILE.TXT",
                    "error": "Cannot find file:\n\"FILE.TXT\""
                }
            }
        ]
    },
    {
        "name": "metric_without_timestamp_and_labels",
        "help": "",
        "type": "UNTYPED",
        "metrics": [
            {
                "value": "12.47"
            }
        ]
    },
    {
        "name": "something_weird",
        "help": "",
        "type": "UNTYPED",
        "metrics": [
            {
                "value": "+Inf",
                "labels": {
                    "problem": "division by zero"
                }
            }
        ]
    },
    {
        "name": "http_request_duration_seconds",
        "help": "A histogram of the request duration.",
        "type": "HISTOGRAM",
        "metrics": [
            {
                "buckets": {
                    "1": "133988",
                    "0.05": "24054",
                    "0.1": "33444",
                    "0.2": "100392",
                    "0.5": "129389",
                    "+Inf": "144320"
                },
                "count": "144320",
                "sum": "53423"
            }
        ]
    },
    {
        "name": "rpc_duration_seconds",
        "help": "A summary of the RPC duration in seconds.",
        "type": "SUMMARY",
        "metrics": [
            {
                "quantiles": {
                    "0.01": "3102",
                    "0.05": "3272",
                    "0.5": "4773",
                    "0.9": "9001",
                    "0.99": "76656"
                },
                "count": "2693",
                "sum": "1.7560473e+07"
            }
        ]
    },
    {
        "name": "jvm_gc_collection_seconds",
        "help": "Time spent in a given JVM garbage collector in seconds.",
        "type": "SUMMARY",
        "metrics": [
            {
                "labels": {
                    "gc": "Copy"
                },
                "count": "104.0",
                "sum": "0.491"
            },
            {
                "labels": {
                    "gc": "MarkSweepCompact"
                },
                "count": "12.0",
                "sum": "0.486"
            }
        ]
    }
]