go.etcd.io/bbolt v1.5.0: Tx

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 go.etcd.io/bbolt.Tx in pkg:golang/go.etcd.io/bbolt@v1.5.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/go.etcd.io/bbolt@v1.5.0
Demonstrate these symbols/APIs:
  - go.etcd.io/bbolt.Tx
Constraints:
  - executionContext: node
Required runtime conditions:
  - ecosystem: npm
  - language: javascript
  - moduleSystem: cjs
  - packageManager: npm@10.9.8
  - runtime: node@22.23.2

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:e700f8ad66558d459eb2b1db8be11904f4f42adba9850622a81bf0f08f8631e5","contract":["Tx.Writable returns true for read-write transactions and false for read-only transactions","Tx.CreateBucket creates a new bucket in a writable transaction and returns ErrTxNotWritable in a read-only transaction","Tx.Commit persists modifications and Tx.Rollback discards uncommitted modifications","Tx.Bucket retrieves an existing bucket and returns nil for non-existent buckets","Tx.DB returns the parent DB instance that created the transaction"],"goal":"verify go.etcd.io/bbolt.Tx in pkg:golang/go.etcd.io/bbolt@v1.5.0","kind":"HOW","packages":["pkg:golang/go.etcd.io/bbolt@v1.5.0"],"schemaVersion":1,"symbols":["go.etcd.io/bbolt.Tx"]},"contractCommand":["go","run","./test"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"golang","libc":"glibc","libcVersion":"2.39","os":"linux","osVersionBucket":"24","packageManager":"go","schemaVersion":1},"license":"MIT-0","packages":["pkg:golang/go.etcd.io/bbolt@v1.5.0"],"schemaVersion":1,"subject":"pkg:golang/go.etcd.io/bbolt@v1.5.0","symbols":["go.etcd.io/bbolt.Tx"],"verifierAdapter":"golang@1"}

module sample

go 1.26.6

require go.etcd.io/bbolt v1.5.0

require golang.org/x/sys v0.45.0 // indirect

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/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/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U=
github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U=
go.etcd.io/bbolt v1.5.0 h1:S7GAl7Fxv12yohbwFfIbQCGDWbQbtDGPET4P/bD4lxU=
go.etcd.io/bbolt v1.5.0/go.mod h1:mkltfYE5aUHQxUct9N9V+Kp7aSjFqjgrhcXIS70Lrdk=
golang.org/x/sync v0.20.0 h1:e0PTpb7pjO8GAtTs2dQ6jYa5BWYlMuX047Dco/pItO4=
golang.org/x/sync v0.20.0/go.mod h1:9xrNwdLfx4jkKbNva9FpL6vEN7evnE43NNNJQ2LF3+0=
golang.org/x/sys v0.45.0 h1:dO4czNzziLiiXplLQgBCEpCvXQ3dnkn0SdaZSYdQ+FY=
golang.org/x/sys v0.45.0/go.mod h1:4GL1E5IUh+htKOUEOaiffhrAeqysfVGipDYzABqnCmw=
gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

package sample

import (
	"fmt"

	bolt "go.etcd.io/bbolt"
)

// OpenDB opens or creates a Bolt database at the specified path.
func OpenDB(path string) (*bolt.DB, error) {
	db, err := bolt.Open(path, 0600, nil)
	if err != nil {
		return nil, fmt.Errorf("failed to open bolt db: %w", err)
	}
	return db, nil
}

// PutKV executes a writable transaction to store a key-value pair in a bucket.
func PutKV(db *bolt.DB, bucketName, key, value []byte) error {
	return db.Update(func(tx *bolt.Tx) error {
		b, err := tx.CreateBucketIfNotExists(bucketName)
		if err != nil {
			return err
		}
		return b.Put(key, value)
	})
}

// GetKV executes a read-only transaction to retrieve a value for a key in a bucket.
func GetKV(db *bolt.DB, bucketName, key []byte) ([]byte, error) {
	var val []byte
	err := db.View(func(tx *bolt.Tx) error {
		b := tx.Bucket(bucketName)
		if b == nil {
			return bolt.ErrBucketNotFound
		}
		v := b.Get(key)
		if v != nil {
			val = make([]byte, len(v))
			copy(val, v)
		}
		return nil
	})
	return val, err
}

{
  "schemaVersion": 1,
  "goal": "verify go.etcd.io/bbolt.Tx in pkg:golang/go.etcd.io/bbolt@v1.5.0",
  "kind": "HOW",
  "packages": [
    "pkg:golang/go.etcd.io/bbolt@v1.5.0"
  ],
  "symbols": [
    "go.etcd.io/bbolt.Tx"
  ],
  "constraints": {
    "executionContext": "node"
  },
  "runtimeConditions": {
    "ecosystem": "npm",
    "language": "javascript",
    "moduleSystem": "cjs",
    "packageManager": "npm@10.9.8",
    "runtime": "node@22.23.2"
  }
}

package main

import (
	"bytes"
	"errors"
	"fmt"
	"os"
	"path/filepath"

	bolt "go.etcd.io/bbolt"
	"sample"
)

func main() {
	tmpDir, err := os.MkdirTemp("", "bbolt-test-*")
	if err != nil {
		fmt.Fprintf(os.Stderr, "FAIL: failed to create temp dir: %v\n", err)
		os.Exit(1)
	}
	defer os.RemoveAll(tmpDir)

	dbPath := filepath.Join(tmpDir, "test.db")
	db, err := sample.OpenDB(dbPath)
	if err != nil {
		fmt.Fprintf(os.Stderr, "FAIL: failed to open db: %v\n", err)
		os.Exit(1)
	}
	defer db.Close()

	bucketName := []byte("users")
	key := []byte("user:1001")
	val := []byte("alice")

	// Assertion 1: Tx.Writable returns true for read-write transactions and false for read-only transactions
	rwTx, err := db.Begin(true)
	if err != nil {
		fmt.Fprintf(os.Stderr, "FAIL: db.Begin(true) failed: %v\n", err)
		os.Exit(1)
	}
	if !rwTx.Writable() {
		fmt.Fprintf(os.Stderr, "FAIL: expected rwTx.Writable() to be true\n")
		os.Exit(1)
	}

	roTx, err := db.Begin(false)
	if err != nil {
		fmt.Fprintf(os.Stderr, "FAIL: db.Begin(false) failed: %v\n", err)
		os.Exit(1)
	}
	if roTx.Writable() {
		fmt.Fprintf(os.Stderr, "FAIL: expected roTx.Writable() to be false\n")
		os.Exit(1)
	}

	// Assertion 2: Tx.CreateBucket creates a new bucket in a writable transaction and returns ErrTxNotWritable in a read-only transaction
	_, err = roTx.CreateBucket(bucketName)
	if !errors.Is(err, bolt.ErrTxNotWritable) {
		fmt.Fprintf(os.Stderr, "FAIL: expected ErrTxNotWritable on read-only transaction, got: %v\n", err)
		os.Exit(1)
	}
	if err := roTx.Rollback(); err != nil {
		fmt.Fprintf(os.Stderr, "FAIL: roTx.Rollback() failed: %v\n", err)
		os.Exit(1)
	}

	b, err := rwTx.CreateBucket(bucketName)
	if err != nil {
		fmt.Fprintf(os.Stderr, "FAIL: rwTx.CreateBucket failed: %v\n", err)
		os.Exit(1)
	}
	if b == nil {
		fmt.Fprintf(os.Stderr, "FAIL: created bucket is nil\n")
		os.Exit(1)
	}
	if err := b.Put(key, val); err != nil {
		fmt.Fprintf(os.Stderr, "FAIL: b.Put failed: %v\n", err)
		os.Exit(1)
	}

	// Assertion 3: Tx.Commit persists modifications and Tx.Rollback discards uncommitted modifications
	if err := rwTx.Commit(); err != nil {
		fmt.Fprintf(os.Stderr, "FAIL: rwTx.Commit failed: %v\n", err)
		os.Exit(1)
	}

	gotVal, err := sample.GetKV(db, bucketName, key)
	if err != nil {
		fmt.Fprintf(os.Stderr, "FAIL: GetKV failed: %v\n", err)
		os.Exit(1)
	}
	if !bytes.Equal(gotVal, val) {
		fmt.Fprintf(os.Stderr, "FAIL: expected value %q, got %q\n", string(val), string(gotVal))
		os.Exit(1)
	}

	rollbackTx, err := db.Begin(true)
	if err != nil {
		fmt.Fprintf(os.Stderr, "FAIL: db.Begin(true) failed: %v\n", err)
		os.Exit(1)
	}
	bRollback := rollbackTx.Bucket(bucketName)
	if err := bRollback.Put([]byte("temp_key"), []byte("temp_val")); err != nil {
		fmt.Fprintf(os.Stderr, "FAIL: put temp_key failed: %v\n", err)
		os.Exit(1)
	}
	if err := rollbackTx.Rollback(); err != nil {
		fmt.Fprintf(os.Stderr, "FAIL: rollbackTx.Rollback failed: %v\n", err)
		os.Exit(1)
	}

	tempVal, err := sample.GetKV(db, bucketName, []byte("temp_key"))
	if err != nil {
		fmt.Fprintf(os.Stderr, "FAIL: GetKV for temp_key failed: %v\n", err)
		os.Exit(1)
	}
	if tempVal != nil {
		fmt.Fprintf(os.Stderr, "FAIL: rolled back key should be nil, got: %q\n", string(tempVal))
		os.Exit(1)
	}

	// Assertion 4: Tx.Bucket retrieves an existing bucket and returns nil for non-existent buckets
	err = db.View(func(tx *bolt.Tx) error {
		if tx.Bucket(bucketName) == nil {
			return fmt.Errorf("expected existing bucket to be non-nil")
		}
		if tx.Bucket([]byte("non_existent_bucket")) != nil {
			return fmt.Errorf("expected non-existent bucket to be nil")
		}
		return nil
	})
	if err != nil {
		fmt.Fprintf(os.Stderr, "FAIL: Tx.Bucket assertions failed: %v\n", err)
		os.Exit(1)
	}

	// Assertion 5: Tx.DB returns the parent DB instance that created the transaction
	err = db.View(func(tx *bolt.Tx) error {
		if tx.DB() != db {
			return fmt.Errorf("expected tx.DB() to match parent db")
		}
		return nil
	})
	if err != nil {
		fmt.Fprintf(os.Stderr, "FAIL: tx.DB() assertion failed: %v\n", err)
		os.Exit(1)
	}

	fmt.Println("PASS: go.etcd.io/bbolt.Tx contract assertions passed")
}