github.com/jackc/pgx/v5 v5.10.0: pgxpool.ParseConfig

Clean-room public code sample — generation instructions

Write a brand-new, minimal, self-contained code sample in this clean-room directory.
Do not copy, paraphrase, or reference any existing project source. Work only from this spec.

A csx.json manifest scaffold already exists. Do not recreate it from memory. Preserve its case.goal, packages and symbols; fill its empty case.contract with exact assertions and correct its environment, commands and verifierAdapter for the files you generate.

Goal: verify github.com/jackc/pgx/v5/pgxpool.ParseConfig in pkg:golang/github.com/jackc/pgx/v5@v5.10.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/github.com/jackc/pgx/v5@v5.10.0
Demonstrate these symbols/APIs:
  - github.com/jackc/pgx/v5/pgxpool.ParseConfig
Constraints:
  - executionContext: node
Required runtime conditions:
  - ecosystem: npm
  - language: javascript
  - moduleSystem: cjs
  - packageManager: npm@11.8.0
  - runtime: node@24.13.1

Rules:
  - One focused purpose; the smallest project that proves the goal.
  - Include a contract test (test/contract.*) that runs OFFLINE and exits 0 exactly when the goal behavior works.
  - Pin every dependency with a lockfile so resolution is reproducible.
  - No secrets, credentials, or tokens. No real URLs (only example.com or localhost). No absolute paths.
  - No personal names, emails, company names, or project identifiers of any kind.
  - No binaries and no generated output (node_modules, dist, target, venv, .git, .env).
  - Keep it under 200 files and 256KB packed.

{"case":{"caseId":"case:sha256:208446599d539a2f3904108c5fc3f917fb56b8c94a7ed51eadc81c800758de57","contract":["pgxpool.ParseConfig parses valid PostgreSQL connection URI into Config with ConnConfig","pgxpool.ParseConfig parses pool parameters including min/max conns, lifetime, idle time, and health check period","pgxpool.ParseConfig parses key-value DSN format connection string","pgxpool.Config.Copy returns an independent clone that preserves all configuration","pgxpool.ParseConfig returns an error for invalid connection URIs and invalid pool parameter values"],"goal":"verify github.com/jackc/pgx/v5/pgxpool.ParseConfig in pkg:golang/github.com/jackc/pgx/v5@v5.10.0","kind":"HOW","packages":["pkg:golang/github.com/jackc/pgx/v5@v5.10.0"],"schemaVersion":1,"symbols":["github.com/jackc/pgx/v5/pgxpool.ParseConfig"]},"contractCommand":["go","run","./test"],"environment":{"arch":"x64","ecosystem":"golang","language":"go","os":"windows","osVersionBucket":"11","packageManager":"go","packageManagerVersion":"1.26.5","runtime":"go","runtimeVersion":"1.26.5","schemaVersion":1},"license":"MIT-0","packages":["pkg:golang/github.com/jackc/pgx/v5@v5.10.0"],"schemaVersion":1,"symbols":["github.com/jackc/pgx/v5/pgxpool.ParseConfig"],"verifierAdapter":"golang@1"}

module sample

go 1.26.5

require github.com/jackc/pgx/v5 v5.10.0

require (
	github.com/jackc/pgpassfile v1.0.0 // indirect
	github.com/jackc/pgservicefile v0.0.0-20240606120523-5a60cdf6a761 // indirect
	github.com/jackc/puddle/v2 v2.2.2 // indirect
	golang.org/x/sync v0.17.0 // indirect
	golang.org/x/text v0.29.0 // indirect
)

github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
github.com/jackc/pgpassfile v1.0.0 h1:/6Hmqy13Ss2zCq62VdNG8tM1wchn8zjSGOBJ6icpsIM=
github.com/jackc/pgpassfile v1.0.0/go.mod h1:CEx0iS5ambNFdcRtxPj5JhEz+xB6uRky5eyVu/W2HEg=
github.com/jackc/pgservicefile v0.0.0-20240606120523-5a60cdf6a761 h1:iCEnooe7UlwOQYpKFhBabPMi4aNAfoODPEFNiAnClxo=
github.com/jackc/pgservicefile v0.0.0-20240606120523-5a60cdf6a761/go.mod h1:5TJZWKEWniPve33vlWYSoGYefn3gLQRzjfDlhSJ9ZKM=
github.com/jackc/pgx/v5 v5.10.0 h1:VhSvgU2jSli8o3AqIEOTJr7rZwAEUVo4E4XhR94Zfr0=
github.com/jackc/pgx/v5 v5.10.0/go.mod h1:mal1tBGAFfLHvZzaYh77YS/eC6IX9OWbRV1QIIM0Jn4=
github.com/jackc/puddle/v2 v2.2.2 h1:PR8nw+E/1w0GLuRFSmiioY6UooMp6KJv0/61nB7icHo=
github.com/jackc/puddle/v2 v2.2.2/go.mod h1:vriiEXHvEE654aYKXXjOvZM39qJ0q+azkZFrfEOc3H4=
github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U=
github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U=
golang.org/x/sync v0.17.0 h1:l60nONMj9l5drqw6jlhIELNv9I0A4OFgRsG9k2oT9Ug=
golang.org/x/sync v0.17.0/go.mod h1:9KTHXmSnoGruLpwFjVSX0lNNA75CykiMECbovNTZqGI=
golang.org/x/text v0.29.0 h1:1neNs90w9YzJ9BocxfsQNHKuAT4pkghyXc4nhZ6sJvk=
golang.org/x/text v0.29.0/go.mod h1:7MhJOA9CD2qZyOKYazxdYMF85OwPdEr9jTtBpO7ydH4=
gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

package main

import (
	"fmt"
	"log"

	"github.com/jackc/pgx/v5/pgxpool"
)

func main() {
	connStr := "postgres://sampleuser:securepwd123@localhost:5432/sampledb?sslmode=disable&pool_max_conns=20&pool_min_conns=5&pool_max_conn_lifetime=1h&pool_max_conn_idle_time=30m&pool_health_check_period=1m"
	config, err := pgxpool.ParseConfig(connStr)
	if err != nil {
		log.Fatalf("failed to parse pgxpool config: %v", err)
	}

	fmt.Printf("Host: %s\n", config.ConnConfig.Host)
	fmt.Printf("Port: %d\n", config.ConnConfig.Port)
	fmt.Printf("Database: %s\n", config.ConnConfig.Database)
	fmt.Printf("User: %s\n", config.ConnConfig.User)
	fmt.Printf("MaxConns: %d\n", config.MaxConns)
	fmt.Printf("MinConns: %d\n", config.MinConns)
	fmt.Printf("MaxConnLifetime: %v\n", config.MaxConnLifetime)
	fmt.Printf("MaxConnIdleTime: %v\n", config.MaxConnIdleTime)
	fmt.Printf("HealthCheckPeriod: %v\n", config.HealthCheckPeriod)

	clone := config.Copy()
	clone.MaxConns = 50
	fmt.Printf("Clone MaxConns: %d, Original MaxConns: %d\n", clone.MaxConns, config.MaxConns)
}

{
  "schemaVersion": 1,
  "goal": "verify github.com/jackc/pgx/v5/pgxpool.ParseConfig in pkg:golang/github.com/jackc/pgx/v5@v5.10.0",
  "kind": "HOW",
  "packages": [
    "pkg:golang/github.com/jackc/pgx/v5@v5.10.0"
  ],
  "symbols": [
    "github.com/jackc/pgx/v5/pgxpool.ParseConfig"
  ],
  "constraints": {
    "executionContext": "node"
  },
  "runtimeConditions": {
    "ecosystem": "npm",
    "language": "javascript",
    "moduleSystem": "cjs",
    "packageManager": "npm@11.8.0",
    "runtime": "node@24.13.1"
  }
}

package main

import (
	"fmt"
	"os"
	"time"

	"github.com/jackc/pgx/v5/pgxpool"
)

func main() {
	// 1. pgxpool.ParseConfig parses valid PostgreSQL connection URI into Config with ConnConfig
	uri := "postgres://sampleuser:securepwd123@localhost:5432/sampledb?sslmode=disable"
	cfg1, err := pgxpool.ParseConfig(uri)
	if err != nil {
		fmt.Fprintf(os.Stderr, "FAIL: pgxpool.ParseConfig valid URI returned error: %v\n", err)
		os.Exit(1)
	}
	if cfg1.ConnConfig == nil {
		fmt.Fprintf(os.Stderr, "FAIL: ConnConfig is nil\n")
		os.Exit(1)
	}
	if cfg1.ConnConfig.Host != "localhost" {
		fmt.Fprintf(os.Stderr, "FAIL: expected host localhost, got %s\n", cfg1.ConnConfig.Host)
		os.Exit(1)
	}
	if cfg1.ConnConfig.Port != 5432 {
		fmt.Fprintf(os.Stderr, "FAIL: expected port 5432, got %d\n", cfg1.ConnConfig.Port)
		os.Exit(1)
	}
	if cfg1.ConnConfig.User != "sampleuser" {
		fmt.Fprintf(os.Stderr, "FAIL: expected user sampleuser, got %s\n", cfg1.ConnConfig.User)
		os.Exit(1)
	}
	if cfg1.ConnConfig.Password != "securepwd123" {
		fmt.Fprintf(os.Stderr, "FAIL: expected password securepwd123, got %s\n", cfg1.ConnConfig.Password)
		os.Exit(1)
	}
	if cfg1.ConnConfig.Database != "sampledb" {
		fmt.Fprintf(os.Stderr, "FAIL: expected database sampledb, got %s\n", cfg1.ConnConfig.Database)
		os.Exit(1)
	}

	// 2. pgxpool.ParseConfig parses pool parameters including min/max conns, lifetime, idle time, and health check period
	uriWithPoolParams := "postgres://sampleuser:securepwd123@localhost:5432/sampledb?pool_max_conns=20&pool_min_conns=5&pool_max_conn_lifetime=1h&pool_max_conn_idle_time=30m&pool_health_check_period=1m&pool_max_conn_lifetime_jitter=5m"
	cfg2, err := pgxpool.ParseConfig(uriWithPoolParams)
	if err != nil {
		fmt.Fprintf(os.Stderr, "FAIL: pgxpool.ParseConfig with pool params returned error: %v\n", err)
		os.Exit(1)
	}
	if cfg2.MaxConns != 20 {
		fmt.Fprintf(os.Stderr, "FAIL: expected MaxConns 20, got %d\n", cfg2.MaxConns)
		os.Exit(1)
	}
	if cfg2.MinConns != 5 {
		fmt.Fprintf(os.Stderr, "FAIL: expected MinConns 5, got %d\n", cfg2.MinConns)
		os.Exit(1)
	}
	if cfg2.MaxConnLifetime != 1*time.Hour {
		fmt.Fprintf(os.Stderr, "FAIL: expected MaxConnLifetime 1h, got %v\n", cfg2.MaxConnLifetime)
		os.Exit(1)
	}
	if cfg2.MaxConnIdleTime != 30*time.Minute {
		fmt.Fprintf(os.Stderr, "FAIL: expected MaxConnIdleTime 30m, got %v\n", cfg2.MaxConnIdleTime)
		os.Exit(1)
	}
	if cfg2.HealthCheckPeriod != 1*time.Minute {
		fmt.Fprintf(os.Stderr, "FAIL: expected HealthCheckPeriod 1m, got %v\n", cfg2.HealthCheckPeriod)
		os.Exit(1)
	}
	if cfg2.MaxConnLifetimeJitter != 5*time.Minute {
		fmt.Fprintf(os.Stderr, "FAIL: expected MaxConnLifetimeJitter 5m, got %v\n", cfg2.MaxConnLifetimeJitter)
		os.Exit(1)
	}

	// 3. pgxpool.ParseConfig parses key-value DSN format connection string
	kvDsn := "host=localhost port=5432 user=sampleuser dbname=sampledb pool_max_conns=15 pool_min_conns=2"
	cfg3, err := pgxpool.ParseConfig(kvDsn)
	if err != nil {
		fmt.Fprintf(os.Stderr, "FAIL: pgxpool.ParseConfig key-value DSN returned error: %v\n", err)
		os.Exit(1)
	}
	if cfg3.ConnConfig.Host != "localhost" || cfg3.MaxConns != 15 || cfg3.MinConns != 2 {
		fmt.Fprintf(os.Stderr, "FAIL: key-value DSN properties mismatch: host=%s, maxConns=%d, minConns=%d\n", cfg3.ConnConfig.Host, cfg3.MaxConns, cfg3.MinConns)
		os.Exit(1)
	}

	// 4. pgxpool.Config.Copy returns an independent clone that preserves all configuration
	clone := cfg2.Copy()
	if clone.MaxConns != cfg2.MaxConns || clone.MinConns != cfg2.MinConns || clone.MaxConnLifetime != cfg2.MaxConnLifetime {
		fmt.Fprintf(os.Stderr, "FAIL: clone initial values do not match original\n")
		os.Exit(1)
	}
	clone.MaxConns = 99
	clone.MinConns = 11
	if cfg2.MaxConns == 99 || cfg2.MinConns == 11 {
		fmt.Fprintf(os.Stderr, "FAIL: mutating clone affected original config\n")
		os.Exit(1)
	}

	// 5. pgxpool.ParseConfig returns an error for invalid connection URIs and invalid pool parameter values
	invalidURI := "://invalid uri string"
	if _, err := pgxpool.ParseConfig(invalidURI); err == nil {
		fmt.Fprintf(os.Stderr, "FAIL: expected error for invalid URI, got nil\n")
		os.Exit(1)
	}

	invalidMaxConns := "postgres://localhost/sampledb?pool_max_conns=invalid_int"
	if _, err := pgxpool.ParseConfig(invalidMaxConns); err == nil {
		fmt.Fprintf(os.Stderr, "FAIL: expected error for non-integer pool_max_conns, got nil\n")
		os.Exit(1)
	}

	invalidDuration := "postgres://localhost/sampledb?pool_max_conn_lifetime=not_a_duration"
	if _, err := pgxpool.ParseConfig(invalidDuration); err == nil {
		fmt.Fprintf(os.Stderr, "FAIL: expected error for invalid duration in pool_max_conn_lifetime, got nil\n")
		os.Exit(1)
	}

	fmt.Println("PASS: all contract assertions passed for github.com/jackc/pgx/v5/pgxpool.ParseConfig in pkg:golang/github.com/jackc/pgx/v5@v5.10.0")
}