usePrometheus

usePrometheus

Package nameWeekly DownloadsVersionLicenseUpdated
@envelop/prometheusDownloadsVersionLicenseNov 19th, 2024

@envelop/prometheus

This plugin tracks the complete execution flow, and reports metrics using Prometheus tracing (based on prom-client).

You can opt-in to collect tracing from the following phases:

  • Successful requests (requestCount)
  • Request summary (requestSummary)
  • errors (categorized by phase)
  • resolvers tracing and runtime
  • deprecated fields usage
  • count of graphql operations
  • parse execution time
  • validate execution time
  • contextBuilding execution time
  • execute execution time

You can also customize each phase reporter, and add custom metadata and labels to the metrics.

Getting Started

yarn add prom-client @envelop/prometheus

Usage Example

import { execute, parse, specifiedRules, subscribe, validate } from 'graphql'
import { envelop, useEngine } from '@envelop/core'
import { usePrometheus } from '@envelop/prometheus'
 
const getEnveloped = envelop({
  plugins: [
    useEngine({ parse, validate, specifiedRules, execute, subscribe }),
    // ... other plugins ...
    usePrometheus({
      // all metrics are disabled by default, please opt-in to the metrics you wish to get
      metrics: {
        graphql_envelop_request_time_summary: true,
        graphql_envelop_phase_parse: true,
        graphql_envelop_phase_validate: true,
        graphql_envelop_phase_context: true,
        graphql_envelop_phase_execute: true,
        graphql_envelop_phase_subscribe: true,
        graphql_envelop_error_result: true,
        graphql_envelop_deprecated_field: true,
        graphql_envelop_request_duration: true,
        graphql_envelop_schema_change: true,
        graphql_envelop_request: true,
 
        // Warning: enabling resolvers level metrics will introduce significant overhead
        graphql_envelop_execute_resolver: true
      },
 
      resolversWhitelist: ['Mutation.*', 'Query.user'] // reports metrics for these resolvers, leave `undefined` to report all fields
    })
  ]
})

Available Metrics

All metrics are disabled by default. You can enable the one you are interested in by setting the corresponding key in the metric option object to true. You can also provide a string to customize the metric name, or an object to provide more options by using createHistogram, createCounter and createSummary (see siimon/prom-client documentation). Histogram metrics can be passed an array of numbers to configure buckets.

Each metric also expose a set of labels. All labels are exposed by default but can be separately disabled by setting the corresponding key in labels option object to false.

A metric can observe events in different phases of of GraphQL request pipeline. By default, if a metric is available, it will observe timing or events in every available phases for this metric. You can configure this by either providing an array instead of true in the metrics config, or use the phases option in the custom metric factory.

graphql_envelop_phase_parse

This metric tracks the duration of the parse phase of the GraphQL execution. It reports the time spent parsing the incoming GraphQL operation.

It is reported as a histogram.

Since you don’t have control over the parsing phase, this metric is mostly useful to track potential attacks. A spike in this metric could indicate someone is trying to send malicious operations to your gateway.

Labels

LabelDescription
operationTypeThe type of the GraphQL operation requested. This can be one of query, mutation, or subscription.
operationNameThe name of the GraphQL operation requested. It will be Anonymous if no operationName is found.

Sample Output

# HELP graphql_envelop_phase_parse Time spent on running GraphQL "parse" function
# TYPE graphql_envelop_phase_parse histogram
graphql_envelop_phase_parse_bucket{le="0.005",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_parse_bucket{le="0.01",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_parse_bucket{le="0.025",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_parse_bucket{le="0.05",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_parse_bucket{le="0.1",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_parse_bucket{le="0.25",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_parse_bucket{le="0.5",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_parse_bucket{le="1",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_parse_bucket{le="2.5",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_parse_bucket{le="5",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_parse_bucket{le="10",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_parse_bucket{le="+Inf",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_parse_sum{operationName="Anonymous",operationType="query"} 0.001
graphql_envelop_phase_parse_count{operationName="Anonymous",operationType="query"} 1

graphql_envelop_phase_validate

This metric tracks the duration of the validate phase of the GraphQL execution. It reports the time spent validating the incoming GraphQL operation.

It is reported as a histogram.

Labels

LabelDescription
operationTypeThe type of the GraphQL operation requested. This can be one of query, mutation, or subscription.
operationNameThe name of the GraphQL operation requested. It will be Anonymous if no operationName is found.

Sample Output

# HELP graphql_envelop_phase_validate Time spent on running GraphQL "validate" function
# TYPE graphql_envelop_phase_validate histogram
graphql_envelop_phase_validate_bucket{le="0.005",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_validate_bucket{le="0.01",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_validate_bucket{le="0.025",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_validate_bucket{le="0.05",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_validate_bucket{le="0.1",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_validate_bucket{le="0.25",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_validate_bucket{le="0.5",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_validate_bucket{le="1",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_validate_bucket{le="2.5",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_validate_bucket{le="5",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_validate_bucket{le="10",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_validate_bucket{le="+Inf",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_validate_sum{operationName="Anonymous",operationType="query"} 0.004
graphql_envelop_phase_validate_count{operationName="Anonymous",operationType="query"} 1

graphql_envelop_phase_context

This metric tracks the duration of the context phase of the GraphQL execution. It reports the time spent building the context object that will be passed to the executors.

It is reported as a histogram.

Labels

LabelDescription
operationTypeThe type of the GraphQL operation requested. This can be one of query, mutation, or subscription.
operationNameThe name of the GraphQL operation requested. It will be Anonymous if no operationName is found.

Sample Output

# HELP graphql_envelop_phase_context Time spent on building the GraphQL context
# TYPE graphql_envelop_phase_context histogram
graphql_envelop_phase_context_bucket{le="0.005",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_context_bucket{le="0.01",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_context_bucket{le="0.025",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_context_bucket{le="0.05",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_context_bucket{le="0.1",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_context_bucket{le="0.25",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_context_bucket{le="0.5",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_context_bucket{le="1",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_context_bucket{le="2.5",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_context_bucket{le="5",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_context_bucket{le="10",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_context_bucket{le="+Inf",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_context_sum{operationName="Anonymous",operationType="query"} 0
graphql_envelop_phase_context_count{operationName="Anonymous",operationType="query"} 1

graphql_envelop_phase_execute

This metric tracks the duration of the execute phase of the GraphQL execution. It reports the time spent actually resolving the response of the incoming operation. This includes the gathering of all the data from all sources required to construct the final response. It is reported as a histogram.

It is the metric that will give you the most insights into the performance of your own code, since this is where most of the work from your code (resolvers) is done.

Labels

LabelDescription
operationTypeThe type of the GraphQL operation requested. This can be one of query, mutation, or subscription.
operationNameThe name of the GraphQL operation requested. It will be Anonymous if no operationName is found.

Sample Output

# HELP graphql_envelop_phase_execute Time spent on running the GraphQL "execute" function
# TYPE graphql_envelop_phase_execute histogram
graphql_envelop_phase_execute_bucket{le="0.005",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_execute_bucket{le="0.01",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_execute_bucket{le="0.025",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_execute_bucket{le="0.05",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_execute_bucket{le="0.1",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_execute_bucket{le="0.25",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_execute_bucket{le="0.5",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_execute_bucket{le="1",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_execute_bucket{le="2.5",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_execute_bucket{le="5",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_execute_bucket{le="10",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_execute_bucket{le="+Inf",operationName="Anonymous",operationType="query"} 1
graphql_envelop_phase_execute_sum{operationName="Anonymous",operationType="query"} 0.002
graphql_envelop_phase_execute_count{operationName="Anonymous",operationType="query"} 1

graphql_envelop_phase_subscribe

This metric tracks the duration of the subscribe phase of the GraphQL execution. It reports the time spent initiating a subscription (which doesn’t include actually sending the first response).

It is reported as a histogram.

Labels

LabelDescription
operationTypeThe type of the GraphQL operation requested. This can be one of query, mutation, or subscription.
operationNameThe name of the GraphQL operation requested. It will be Anonymous if no operationName is found.

Sample Output

# HELP graphql_envelop_phase_subscribe Time spent on running the GraphQL "subscribe" function
# TYPE graphql_envelop_phase_subscribe histogram
graphql_envelop_phase_subscribe_bucket{le="0.005",operationName="Anonymous",operationType="subscription"} 0
graphql_envelop_phase_subscribe_bucket{le="0.01",operationName="Anonymous",operationType="subscription"} 0
graphql_envelop_phase_subscribe_bucket{le="0.025",operationName="Anonymous",operationType="subscription"} 1
graphql_envelop_phase_subscribe_bucket{le="0.05",operationName="Anonymous",operationType="subscription"} 1
graphql_envelop_phase_subscribe_bucket{le="0.1",operationName="Anonymous",operationType="subscription"} 1
graphql_envelop_phase_subscribe_bucket{le="0.25",operationName="Anonymous",operationType="subscription"} 1
graphql_envelop_phase_subscribe_bucket{le="0.5",operationName="Anonymous",operationType="subscription"} 1
graphql_envelop_phase_subscribe_bucket{le="1",operationName="Anonymous",operationType="subscription"} 1
graphql_envelop_phase_subscribe_bucket{le="2.5",operationName="Anonymous",operationType="subscription"} 1
graphql_envelop_phase_subscribe_bucket{le="5",operationName="Anonymous",operationType="subscription"} 1
graphql_envelop_phase_subscribe_bucket{le="10",operationName="Anonymous",operationType="subscription"} 1
graphql_envelop_phase_subscribe_bucket{le="+Inf",operationName="Anonymous",operationType="subscription"} 1
graphql_envelop_phase_subscribe_sum{operationName="Anonymous",operationType="subscription"} 0.011
graphql_envelop_phase_subscribe_count{operationName="Anonymous",operationType="subscription"} 1

graphql_envelop_request_duration

This metric tracks the duration of the complete GraphQL operation execution.

It is reported as a histogram.

Labels

LabelDescription
operationTypeThe type of the GraphQL operation requested. This can be one of query, mutation, or subscription.
operationNameThe name of the GraphQL operation requested. It will be Anonymous if no operationName is found.

Sample Output

# HELP graphql_envelop_request_duration Time spent on running the GraphQL operation from parse to execute
# TYPE graphql_envelop_request_duration histogram
graphql_envelop_request_duration_bucket{le="0.005",operationName="Anonymous",operationType="subscription"} 0
graphql_envelop_request_duration_bucket{le="0.01",operationName="Anonymous",operationType="subscription"} 0
graphql_envelop_request_duration_bucket{le="0.025",operationName="Anonymous",operationType="subscription"} 1
graphql_envelop_request_duration_bucket{le="0.05",operationName="Anonymous",operationType="subscription"} 1
graphql_envelop_request_duration_bucket{le="0.1",operationName="Anonymous",operationType="subscription"} 1
graphql_envelop_request_duration_bucket{le="0.25",operationName="Anonymous",operationType="subscription"} 1
graphql_envelop_request_duration_bucket{le="0.5",operationName="Anonymous",operationType="subscription"} 1
graphql_envelop_request_duration_bucket{le="1",operationName="Anonymous",operationType="subscription"} 1
graphql_envelop_request_duration_bucket{le="2.5",operationName="Anonymous",operationType="subscription"} 1
graphql_envelop_request_duration_bucket{le="5",operationName="Anonymous",operationType="subscription"} 1
graphql_envelop_request_duration_bucket{le="10",operationName="Anonymous",operationType="subscription"} 1
graphql_envelop_request_duration_bucket{le="+Inf",operationName="Anonymous",operationType="subscription"} 1
graphql_envelop_request_duration_sum{operationName="Anonymous",operationType="subscription"} 0.011
graphql_envelop_request_duration_count{operationName="Anonymous",operationType="subscription"} 1

graphql_envelop_request_time_summary

This metric provides a summary of the time spent on the GraphQL operation execution.

It reports the same timing than graphql_envelop_request_duration but as a summary.

Labels

LabelDescription
operationTypeThe type of the GraphQL operation requested. This can be one of query, mutation, or subscription.
operationNameThe name of the GraphQL operation requested. It will be Anonymous if no operationName is found.

Sample output

# HELP graphql_envelop_request_time_summary Summary to measure the time to complete GraphQL operations
# TYPE graphql_envelop_request_time_summary summary
graphql_envelop_request_time_summary{quantile="0.01",operationName="Anonymous",operationType="subscription"} 0.022
graphql_envelop_request_time_summary{quantile="0.05",operationName="Anonymous",operationType="subscription"} 0.022
graphql_envelop_request_time_summary{quantile="0.5",operationName="Anonymous",operationType="subscription"} 0.022
graphql_envelop_request_time_summary{quantile="0.9",operationName="Anonymous",operationType="subscription"} 0.022
graphql_envelop_request_time_summary{quantile="0.95",operationName="Anonymous",operationType="subscription"} 0.022
graphql_envelop_request_time_summary{quantile="0.99",operationName="Anonymous",operationType="subscription"} 0.022
graphql_envelop_request_time_summary{quantile="0.999",operationName="Anonymous",operationType="subscription"} 0.022
graphql_envelop_request_time_summary_sum{operationName="Anonymous",operationType="subscription"} 0.022
graphql_envelop_request_time_summary_count{operationName="Anonymous",operationType="subscription"} 1

graphql_envelop_error_result

This metric tracks the number of errors that occurred returned by the GraphQL execution. It counts all errors found in the final response, but it also includes errors from other GraphQL processing phases (parsing, validation and context building).

It is exposed as a counter.

Labels

Depending on the phase when the error occurred, some labels may be missing. For example, if the error occurred during the context phase, only the phase label will be present.

LabelDescription
pathThe path of the field that caused the error. It can be undefined if the error is not related to a given field.
phaseThe phase of the GraphQL execution where the error occurred. It can be parse, validate, context, execute (for every operation types including subscriptions).
operationTypeThe type of the GraphQL operation requested. This can be one of query, mutation, or subscription.
operationNameThe name of the GraphQL operation requested. It will be Anonymous if no operationName is found.

Sample Output

# HELP graphql_envelop_error_result Counts the amount of errors reported from all phases
# TYPE graphql_envelop_error_result counter
graphql_envelop_error_result{operationName="Anonymous",operationType="query",path="undefined",phase="execute"} 1

graphql_envelop_request

This metric tracks the number of GraphQL operations executed. It counts all operations, either failed or successful, including subscriptions.

It is exposed as a counter.

Labels

LabelDescription
operationTypeThe type of the GraphQL operation requested. This can be one of query, mutation, or subscription.
operationNameThe name of the GraphQL operation requested. It will be Anonymous if no operationName is found.

Sample output

# HELP graphql_envelop_request Counts the amount of GraphQL requests executed through Envelop
# TYPE graphql_envelop_request counter
graphql_envelop_request{operationName="Anonymous",operationType="query"} 1

graphql_envelop_deprecated_field

This metric tracks the number of deprecated fields used in the GraphQL operation.

Labels

LabelDescription
fieldNameThe name of the deprecated field that has been used.
typeNameThe name of the parent type of the deprecated field that has been used.
operationTypeThe type of the GraphQL operation requested. This can be one of query, mutation, or subscription.
operationNameThe name of the GraphQL operation requested. It will be Anonymous if no operationName is found.

Sample Output

# HELP graphql_envelop_deprecated_field Counts the amount of deprecated fields used in selection sets
# TYPE graphql_envelop_deprecated_field counter
graphql_envelop_deprecated_field{operationName="Anonymous",operationType="query",fieldName="hello",typeName="Query"} 1

graphql_envelop_schema_change

This metric tracks the number of schema changes that have occurred since the gateway started.

If you are using a plugin that modifies the schema on the fly, be aware that this metric will also include updates made by those plugins. Which means that one schema update can actually trigger multiple schema changes.

Labels

This metric does not include any labels.

Sample output

# HELP graphql_envelop_schema_change Counts the amount of schema changes
# TYPE graphql_envelop_schema_change counter
graphql_envelop_schema_change 1

graphql_envelop_execute_resolver

Caution: Enabling resolvers level metrics will introduce significant overhead.

We highly recommend to enable this for debugging purpose only.

This metric tracks the duration of each resolver execution. It reports the time spent only on additional resolvers, not on fields that are resolved by a subgraph. It is up to the subgraph server to implement resolver level metrics, the gateway can’t remotely track their execution time.

Filter resolvers to instrument

To mitigate the cost of instrumenting all resolvers, you can explicitly list the fields that should be instrumented by providing a list of field names to the instrumentResolvers option.

It is a list of strings in the form of TypeName.fieldName. For example, to instrument the hello root query, you would use Query.hello.

You can also use wildcards to instrument all the fields for a type. For example, to instrument all root queries, you would use Query.*.

Labels

LabelDescription
operationTypeThe type of the GraphQL operation requested. This can be one of query, mutation, or subscription.
operationNameThe name of the GraphQL operation requested. It will be Anonymous if no operationName is found.
fieldNameThe name of the field being resolved.
typeNameThe name of the parent type of the field being resolved.
returnTypeThe name of the return type of the field being resolved.

Sample output

# HELP graphql_envelop_execute_resolver Time spent on running the GraphQL resolvers
# TYPE graphql_envelop_execute_resolver histogram
graphql_envelop_execute_resolver_bucket{le="0.005",operationName="Anonymous",operationType="query",fieldName="hello",typeName="Query",returnType="String!"} 1
graphql_envelop_execute_resolver_bucket{le="0.01",operationName="Anonymous",operationType="query",fieldName="hello",typeName="Query",returnType="String!"} 1
graphql_envelop_execute_resolver_bucket{le="0.025",operationName="Anonymous",operationType="query",fieldName="hello",typeName="Query",returnType="String!"} 1
graphql_envelop_execute_resolver_bucket{le="0.05",operationName="Anonymous",operationType="query",fieldName="hello",typeName="Query",returnType="String!"} 1
graphql_envelop_execute_resolver_bucket{le="0.1",operationName="Anonymous",operationType="query",fieldName="hello",typeName="Query",returnType="String!"} 1
graphql_envelop_execute_resolver_bucket{le="0.25",operationName="Anonymous",operationType="query",fieldName="hello",typeName="Query",returnType="String!"} 1
graphql_envelop_execute_resolver_bucket{le="0.5",operationName="Anonymous",operationType="query",fieldName="hello",typeName="Query",returnType="String!"} 1
graphql_envelop_execute_resolver_bucket{le="1",operationName="Anonymous",operationType="query",fieldName="hello",typeName="Query",returnType="String!"} 1
graphql_envelop_execute_resolver_bucket{le="2.5",operationName="Anonymous",operationType="query",fieldName="hello",typeName="Query",returnType="String!"} 1
graphql_envelop_execute_resolver_bucket{le="5",operationName="Anonymous",operationType="query",fieldName="hello",typeName="Query",returnType="String!"} 1
graphql_envelop_execute_resolver_bucket{le="10",operationName="Anonymous",operationType="query",fieldName="hello",typeName="Query",returnType="String!"} 1
graphql_envelop_execute_resolver_bucket{le="+Inf",operationName="Anonymous",operationType="query",fieldName="hello",typeName="Query",returnType="String!"} 1
graphql_envelop_execute_resolver_sum{operationName="Anonymous",operationType="query",fieldName="hello",typeName="Query",returnType="String!"} 0
graphql_envelop_execute_resolver_count{operationName="Anonymous",operationType="query",fieldName="hello",typeName="Query",returnType="String!"} 1

Configuration

Custom registry

You can customize the prom-client Registry object if you are using a custom one, by passing it along with the configuration object:

import { execute, parse, specifiedRules, subscribe, validate } from 'graphql'
import { Registry } from 'prom-client'
import { envelop, useEngine } from '@envelop/core'
 
const myRegistry = new Registry()
 
const getEnveloped = envelop({
  plugins: [
    useEngine({ parse, validate, specifiedRules, execute, subscribe }),
    // ... other plugins ...
    usePrometheus({
      // ... config ...
      registry: myRegistry
    })
  ]
})

Note: if you are using custom prom-client instances, you need to make sure to pass your registry there as well.

Introspection

You can exclude introspection from monitoring by setting skipIntrospection: true in your config object.

Custom prom-client instances

Each tracing field supports custom prom-client objects, and custom labels a metadata, you can create a custom extraction function for every Histogram / Summary / Counter:

import { execute, parse, specifiedRules, subscribe, validate } from 'graphql'
import { Histogram, register as registry } from 'prom-client'
import { envelop, useEngine } from '@envelop/core'
import { createHistogram, usePrometheus } from '@envelop/prometheus'
 
const getEnveloped = envelop({
  plugins: [
    useEngine({ parse, validate, specifiedRules, execute, subscribe }),
    usePrometheus({
      metrics: {
        graphql_envelop_phase_parse: createHistogram({
          registry: registry // if you are not using the default one, make sure to add your custom registry,
          histogram: new Histogram({
            name: 'my_custom_name',
            help: 'HELP ME',
            labelNames: ['opText'] as const,
          }),
          phases: ['parse'], // This is an array of phases that should be hooked for this metric
          fillLabelsFn: params => {
            // if you wish to fill your `labels` with metadata, you can use the params in order to get access to things like DocumentNode, operationName, operationType, `error` (for error metrics) and `info` (for resolvers metrics)
            return {
              opText: print(params.document)
            }
          }
        }),
      }
    })
  ]
})

Configure metric phases

Each metric observes timing or events in different phases of the GraphQL request pipeline.

You can configure which phases are observed for a given metric by providing an array of phases instead of true for any metric configuration. You can also configure the phases when using custom metrics factories by providing the phases option.

By default, all available phases are enabled when the metric is enabled.

import { execute, parse, specifiedRules, subscribe, validate } from 'graphql'
import { envelop, useEngine } from '@envelop/core'
import { usePrometheus } from '@envelop/prometheus'
 
const getEnveloped = envelop({
  plugins: [
    useEngine({ parse, validate, specifiedRules, execute, subscribe }),
    usePrometheus({
      metrics: {
        graphql_envelop_phase_error: ['execute', 'subscribe'] // only trace errors of execute and subscribe phases
      }
    })
  ]
})

Skip observation based on request context

To save bandwidth or storage, you can reduce the amount of reported values by filtering which events are observed based on the request context.

For example, you can only monitor a subset of operations, because they are critical or that you want to debug it’s performance:

import { execute, parse, specifiedRules, subscribe, validate } from 'graphql'
import { envelop, useEngine } from '@envelop/core'
import { usePrometheus } from '@envelop/prometheus'
 
const TRACKED_OPERATION_NAMES = [
  // make a list of operation that you want to monitor
]
 
const getEnveloped = envelop({
  plugins: [
    useEngine({ parse, validate, specifiedRules, execute, subscribe }),
    usePrometheus({
      metrics: {
        graphql_yoga_http_duration: createHistogram({
          registry,
          histogram: {
            name: 'graphql_yoga_http_duration',
            help: 'Time spent on HTTP connection',
            labelNames: ['operation_name']
          },
          fillLabelsFn: ({ operationName }, _rawContext) => ({
            operation_name: operationName
          }),
          shouldObserve: context => TRACKED_OPERATIONS.includes(context?.params?.operationName)
        })
      }
    })
  ]
})

Caveats

Due to Prometheus client API limitations, if this plugin is initialized multiple times, only the metrics configuration of the first initialization will be applied.

If necessary, use a different registry instance for each plugin instance, or clear the registry before plugin initialization.

function usePrometheusWithRegistry() {
  // create a new registry instance for each plugin instance
  const registry = new Registry()
 
  // or just clear the registry if you use only on plugin instance at a time
  registry.clear()
 
  return usePrometheus({
    registry,
    ...
  })
}

Keep in mind that this implies potential data loss in pull mode if some data is produced between last pull and the re-initialization of the plugin.