README
Storm
Storm is a simple and powerful toolkit for BoltDB. Basically, Storm provides indexes, a wide range of methods to store and fetch data, an advanced query system, and much more.
In addition to the examples below, see also the examples in the GoDoc.
Table of Contents
- Getting Started
- Import Storm
- Open a database
- Simple CRUD system
- Nodes and nested buckets
- Simple Key/Value store
- BoltDB
- Migrations
- License
- Credits
Getting Started
go get -u github.com/asdine/storm
Import Storm
import "github.com/asdine/storm"
Open a database
Quick way of opening a database
db, err := storm.Open("my.db")
defer db.Close()
Open
can receive multiple options to customize the way it behaves. See Options below
Simple CRUD system
Declare your structures
type User struct {
ID int // primary key
Group string `storm:"index"` // this field will be indexed
Email string `storm:"unique"` // this field will be indexed with a unique constraint
Name string // this field will not be indexed
Age int `storm:"index"`
}
The primary key can be of any type as long as it is not a zero value. Storm will search for the tag id
, if not present Storm will search for a field named ID
.
type User struct {
ThePrimaryKey string `storm:"id"`// primary key
Group string `storm:"index"` // this field will be indexed
Email string `storm:"unique"` // this field will be indexed with a unique constraint
Name string // this field will not be indexed
}
Storm handles tags in nested structures with the inline
tag
type Base struct {
Ident bson.ObjectId `storm:"id"`
}
type User struct {
Base `storm:"inline"`
Group string `storm:"index"`
Email string `storm:"unique"`
Name string
CreatedAt time.Time `storm:"index"`
}
Save your object
user := User{
ID: 10,
Group: "staff",
Email: "john@provider.com",
Name: "John",
Age: 21,
CreatedAt: time.Now(),
}
err := db.Save(&user)
// err == nil
user.ID++
err = db.Save(&user)
// err == storm.ErrAlreadyExists
That's it.
Save
creates or updates all the required indexes and buckets, checks the unique constraints and saves the object to the store.
Auto Increment
Storm can auto increment integer values so you don't have to worry about that when saving your objects. Also, the new value is automatically inserted in your field.
type Product struct {
Pk int `storm:"id,increment"` // primary key with auto increment
Name string
IntegerField uint64 `storm:"increment"`
IndexedIntegerField uint32 `storm:"index,increment"`
UniqueIntegerField int16 `storm:"unique,increment=100"` // the starting value can be set
}
p := Product{Name: "Vaccum Cleaner"}
fmt.Println(p.Pk)
fmt.Println(p.IntegerField)
fmt.Println(p.IndexedIntegerField)
fmt.Println(p.UniqueIntegerField)
// 0
// 0
// 0
// 0
_ = db.Save(&p)
fmt.Println(p.Pk)
fmt.Println(p.IntegerField)
fmt.Println(p.IndexedIntegerField)
fmt.Println(p.UniqueIntegerField)
// 1
// 1
// 1
// 100
Simple queries
Any object can be fetched, indexed or not. Storm uses indexes when available, otherwhise it uses the query system.
Fetch one object
var user User
err := db.One("Email", "john@provider.com", &user)
// err == nil
err = db.One("Name", "John", &user)
// err == nil
err = db.One("Name", "Jack", &user)
// err == storm.ErrNotFound
Fetch multiple objects
var users []User
err := db.Find("Group", "staff", &users)
Fetch all objects
var users []User
err := db.All(&users)
Fetch all objects sorted by index
var users []User
err := db.AllByIndex("CreatedAt", &users)
Fetch a range of objects
var users []User
err := db.Range("Age", 10, 21, &users)
Fetch objects by prefix
var users []User
err := db.Prefix("Name", "Jo", &users)
Skip, Limit and Reverse
var users []User
err := db.Find("Group", "staff", &users, storm.Skip(10))
err = db.Find("Group", "staff", &users, storm.Limit(10))
err = db.Find("Group", "staff", &users, storm.Reverse())
err = db.Find("Group", "staff", &users, storm.Limit(10), storm.Skip(10), storm.Reverse())
err = db.All(&users, storm.Limit(10), storm.Skip(10), storm.Reverse())
err = db.AllByIndex("CreatedAt", &users, storm.Limit(10), storm.Skip(10), storm.Reverse())
err = db.Range("Age", 10, 21, &users, storm.Limit(10), storm.Skip(10), storm.Reverse())
Delete an object
err := db.DeleteStruct(&user)
Update an object
// Update multiple fields
err := db.Update(&User{ID: 10, Name: "Jack", Age: 45})
// Update a single field
err := db.UpdateField(&User{ID: 10}, "Age", 0)
Initialize buckets and indexes before saving an object
err := db.Init(&User{})
Useful when starting your application
Drop a bucket
Using the struct
err := db.Drop(&User)
Using the bucket name
err := db.Drop("User")
Re-index a bucket
err := db.ReIndex(&User{})
Useful when the structure has changed
Advanced queries
For more complex queries, you can use the Select
method.
Select
takes any number of Matcher
from the q
package.
Here are some common Matchers:
// Equality
q.Eq("Name", John)
// Strictly greater than
q.Gt("Age", 7)
// Lesser than or equal to
q.Lte("Age", 77)
// Regex with name that starts with the letter D
q.Re("Name", "^D")
// In the given slice of values
q.In("Group", []string{"Staff", "Admin"})
Matchers can also be combined with And
, Or
and Not
:
// Match if all match
q.And(
q.Gt("Age", 7),
q.Re("Name", "^D")
)
// Match if one matches
q.Or(
q.Re("Name", "^A"),
q.Not(
q.Re("Name", "^B")
),
q.Re("Name", "^C"),
q.In("Group", []string{"Staff", "Admin"}),
q.And(
q.StrictEq("Password", []byte(password)),
q.Eq("Registered", true)
)
)
You can find the complete list in the documentation.
Select
takes any number of matchers and wraps them into a q.And()
so it's not necessary to specify it. It returns a Query
type.
query := db.Select(q.Gte("Age", 7), q.Lte("Age", 77))
The Query
type contains methods to filter and order the records.
// Limit
query = query.Limit(10)
// Skip
query = query.Skip(20)
// Calls can also be chained
query = query.Limit(10).Skip(20).OrderBy("Age").Reverse()
But also to specify how to fetch them.
var users []User
err = query.Find(&users)
var user User
err = query.First(&user)
Examples with Select
:
// Find all users with an ID between 10 and 100
err = db.Select(q.Gte("ID", 10), q.Lte("ID", 100)).Find(&users)
// Nested matchers
err = db.Select(q.Or(
q.Gt("ID", 50),
q.Lt("Age", 21),
q.And(
q.Eq("Group", "admin"),
q.Gte("Age", 21),
),
)).Find(&users)
query := db.Select(q.Gte("ID", 10), q.Lte("ID", 100)).Limit(10).Skip(5).Reverse().OrderBy("Age", "Name")
// Find multiple records
err = query.Find(&users)
// or
err = db.Select(q.Gte("ID", 10), q.Lte("ID", 100)).Limit(10).Skip(5).Reverse().OrderBy("Age", "Name").Find(&users)
// Find first record
err = query.First(&user)
// or
err = db.Select(q.Gte("ID", 10), q.Lte("ID", 100)).Limit(10).Skip(5).Reverse().OrderBy("Age", "Name").First(&user)
// Delete all matching records
err = query.Delete(new(User))
// Fetching records one by one (useful when the bucket contains a lot of records)
query = db.Select(q.Gte("ID", 10),q.Lte("ID", 100)).OrderBy("Age", "Name")
err = query.Each(new(User), func(record interface{}) error) {
u := record.(*User)
...
return nil
}
See the documentation for a complete list of methods.
Transactions
tx, err := db.Begin(true)
if err != nil {
return err
}
defer tx.Rollback()
accountA.Amount -= 100
accountB.Amount += 100
err = tx.Save(accountA)
if err != nil {
return err
}
err = tx.Save(accountB)
if err != nil {
return err
}
return tx.Commit()
Options
Storm options are functions that can be passed when constructing you Storm instance. You can pass it any number of options.
BoltOptions
By default, Storm opens a database with the mode 0600
and a timeout of one second.
You can change this behavior by using BoltOptions
db, err := storm.Open("my.db", storm.BoltOptions(0600, &bolt.Options{Timeout: 1 * time.Second}))
MarshalUnmarshaler
To store the data in BoltDB, Storm marshals it in JSON by default. If you wish to change this behavior you can pass a codec that implements codec.MarshalUnmarshaler
via the storm.Codec
option:
db := storm.Open("my.db", storm.Codec(myCodec))
Provided Codecs
You can easily implement your own MarshalUnmarshaler
, but Storm comes with built-in support for JSON (default), GOB, Sereal, Protocol Buffers and MessagePack.
These can be used by importing the relevant package and use that codec to configure Storm. The example below shows all variants (without proper error handling):
import (
"github.com/asdine/storm"
"github.com/asdine/storm/codec/gob"
"github.com/asdine/storm/codec/json"
"github.com/asdine/storm/codec/sereal"
"github.com/asdine/storm/codec/protobuf"
"github.com/asdine/storm/codec/msgpack"
)
var gobDb, _ = storm.Open("gob.db", storm.Codec(gob.Codec))
var jsonDb, _ = storm.Open("json.db", storm.Codec(json.Codec))
var serealDb, _ = storm.Open("sereal.db", storm.Codec(sereal.Codec))
var protobufDb, _ = storm.Open("protobuf.db", storm.Codec(protobuf.Codec))
var msgpackDb, _ = storm.Open("msgpack.db", storm.Codec(msgpack.Codec))
Tip: Adding Storm tags to generated Protobuf files can be tricky. A good solution is to use this tool to inject the tags during the compilation.
Use existing Bolt connection
You can use an existing connection and pass it to Storm
bDB, _ := bolt.Open(filepath.Join(dir, "bolt.db"), 0600, &bolt.Options{Timeout: 10 * time.Second})
db := storm.Open("my.db", storm.UseDB(bDB))
Batch mode
Batch mode can be enabled to speed up concurrent writes (see Batch read-write transactions)
db := storm.Open("my.db", storm.Batch())
Nodes and nested buckets
Storm takes advantage of BoltDB nested buckets feature by using storm.Node
.
A storm.Node
is the underlying object used by storm.DB
to manipulate a bucket.
To create a nested bucket and use the same API as storm.DB
, you can use the DB.From
method.
repo := db.From("repo")
err := repo.Save(&Issue{
Title: "I want more features",
Author: user.ID,
})
err = repo.Save(newRelease("0.10"))
var issues []Issue
err = repo.Find("Author", user.ID, &issues)
var release Release
err = repo.One("Tag", "0.10", &release)
You can also chain the nodes to create a hierarchy
chars := db.From("characters")
heroes := chars.From("heroes")
enemies := chars.From("enemies")
items := db.From("items")
potions := items.From("consumables").From("medicine").From("potions")
You can even pass the entire hierarchy as arguments to From
:
privateNotes := db.From("notes", "private")
workNotes := db.From("notes", "work")
Node options
A Node can also be configured. Activating an option on a Node creates a copy, so a Node is always thread-safe.
n := db.From("my-node")
Give a bolt.Tx transaction to the Node
n = n.WithTransaction(tx)
Enable batch mode
n = n.WithBatch(true)
Use a Codec
n = n.WithCodec(gob.Codec)
Simple Key/Value store
Storm can be used as a simple, robust, key/value store that can store anything. The key and the value can be of any type as long as the key is not a zero value.
Saving data :
db.Set("logs", time.Now(), "I'm eating my breakfast man")
db.Set("sessions", bson.NewObjectId(), &someUser)
db.Set("weird storage", "754-3010", map[string]interface{}{
"hair": "blonde",
"likes": []string{"cheese", "star wars"},
})
Fetching data :
user := User{}
db.Get("sessions", someObjectId, &user)
var details map[string]interface{}
db.Get("weird storage", "754-3010", &details)
db.Get("sessions", someObjectId, &details)
Deleting data :
db.Delete("sessions", someObjectId)
db.Delete("weird storage", "754-3010")
BoltDB
BoltDB is still easily accessible and can be used as usual
db.Bolt.View(func(tx *bolt.Tx) error {
bucket := tx.Bucket([]byte("my bucket"))
val := bucket.Get([]byte("any id"))
fmt.Println(string(val))
return nil
})
A transaction can be also be passed to Storm
db.Bolt.Update(func(tx *bolt.Tx) error {
...
dbx := db.WithTransaction(tx)
err = dbx.Save(&user)
...
return nil
})
Migrations
You can use the migration tool to migrate databases that use older version of Storm. See this README for more informations.
License
MIT
Credits
Documentation
Index ¶
- Constants
- Variables
- func AutoIncrement() func(*DB) error
- func Batch() func(*DB) error
- func BoltOptions(mode os.FileMode, options *bolt.Options) func(*DB) error
- func Codec(c codec.MarshalUnmarshaler) func(*DB) error
- func Limit(limit int) func(*index.Options)
- func Reverse() func(*index.Options)
- func Root(root ...string) func(*DB) error
- func Skip(offset int) func(*index.Options)
- func UseDB(b *bolt.DB) func(*DB) error
- type BucketScanner
- type DB
- func (s *DB) All(to interface{}, options ...func(*index.Options)) error
- func (s *DB) AllByIndex(fieldName string, to interface{}, options ...func(*index.Options)) error
- func (s *DB) Begin(writable bool) (Node, error)
- func (s *DB) Bucket() []string
- func (s *DB) Close() error
- func (s *DB) Codec() codec.MarshalUnmarshaler
- func (s *DB) Commit() error
- func (s *DB) Count(data interface{}) (int, error)
- func (s *DB) CreateBucketIfNotExists(tx *bolt.Tx, bucket string) (*bolt.Bucket, error)
- func (s *DB) Delete(bucketName string, key interface{}) error
- func (s *DB) DeleteStruct(data interface{}) error
- func (s *DB) Drop(data interface{}) error
- func (s *DB) Find(fieldName string, value interface{}, to interface{}, ...) error
- func (s *DB) From(root ...string) Node
- func (s *DB) Get(bucketName string, key interface{}, to interface{}) error
- func (s *DB) GetBucket(tx *bolt.Tx, children ...string) *bolt.Bucket
- func (s *DB) GetBytes(bucketName string, key interface{}) ([]byte, error)
- func (s *DB) Init(data interface{}) error
- func (s *DB) One(fieldName string, value interface{}, to interface{}) error
- func (s *DB) Prefix(fieldName string, prefix string, to interface{}, ...) error
- func (s *DB) PrefixScan(prefix string) []Node
- func (s *DB) Range(fieldName string, min, max, to interface{}, options ...func(*index.Options)) error
- func (s *DB) RangeScan(min, max string) []Node
- func (s *DB) ReIndex(data interface{}) error
- func (s *DB) Remove(data interface{}) error
- func (s *DB) Rollback() error
- func (s *DB) Save(data interface{}) error
- func (s *DB) Select(matchers ...q.Matcher) Query
- func (s *DB) Set(bucketName string, key interface{}, value interface{}) error
- func (s *DB) SetBytes(bucketName string, key interface{}, value []byte) error
- func (s *DB) Update(data interface{}) error
- func (s *DB) UpdateField(data interface{}, fieldName string, value interface{}) error
- func (s *DB) WithBatch(enabled bool) Node
- func (s *DB) WithCodec(codec codec.MarshalUnmarshaler) Node
- func (s *DB) WithTransaction(tx *bolt.Tx) Node
- type Finder
- type KeyValueStore
- type Node
- type Query
- type Tx
- type TypeStore
Examples ¶
Constants ¶
const Version = "1.0.0"
Version of Storm
Variables ¶
var ( // ErrNoID is returned when no ID field or id tag is found in the struct. ErrNoID = errors.New("missing struct tag id or ID field") // ErrZeroID is returned when the ID field is a zero value. ErrZeroID = errors.New("id field must not be a zero value") // ErrBadType is returned when a method receives an unexpected value type. ErrBadType = errors.New("provided data must be a struct or a pointer to struct") // ErrAlreadyExists is returned uses when trying to set an existing value on a field that has a unique index. ErrAlreadyExists = errors.New("already exists") // ErrNilParam is returned when the specified param is expected to be not nil. ErrNilParam = errors.New("param must not be nil") // ErrUnknownTag is returned when an unexpected tag is specified. ErrUnknownTag = errors.New("unknown tag") // ErrIdxNotFound is returned when the specified index is not found. ErrIdxNotFound = errors.New("index not found") // ErrSlicePtrNeeded is returned when an unexpected value is given, instead of a pointer to slice. ErrSlicePtrNeeded = errors.New("provided target must be a pointer to slice") // ErrSlicePtrNeeded is returned when an unexpected value is given, instead of a pointer to struct. ErrStructPtrNeeded = errors.New("provided target must be a pointer to struct") // ErrSlicePtrNeeded is returned when an unexpected value is given, instead of a pointer. ErrPtrNeeded = errors.New("provided target must be a pointer to a valid variable") // ErrNoName is returned when the specified struct has no name. ErrNoName = errors.New("provided target must have a name") // ErrNotFound is returned when the specified record is not saved in the bucket. ErrNotFound = errors.New("not found") // ErrNotInTransaction is returned when trying to rollback or commit when not in transaction. ErrNotInTransaction = errors.New("not in transaction") // ErrUnAddressable is returned when a struct or an exported field of a struct is unaddressable ErrUnAddressable = errors.New("unaddressable value") // ErrIncompatibleValue is returned when trying to set a value with a different type than the chosen field ErrIncompatibleValue = errors.New("incompatible value") // ErrDifferentCodec is returned when using a codec different than the first codec used with the bucket. ErrDifferentCodec = errors.New("the selected codec is incompatible with this bucket") )
Errors
Functions ¶
func AutoIncrement ¶
AutoIncrement used to enable bolt.NextSequence on empty integer ids. Deprecated: Set the increment tag to the id field instead.
func BoltOptions ¶
BoltOptions used to pass options to BoltDB.
func Codec ¶
func Codec(c codec.MarshalUnmarshaler) func(*DB) error
Codec used to set a custom encoder and decoder. The default is JSON.
func Limit ¶
Limit sets the maximum number of records to return
Example ¶
Code:
package main import ( "fmt" "github.com/asdine/storm" "io/ioutil" "log" "os" "path/filepath" "strings" "time" ) func main() { dir, db := prepareDB() defer os.RemoveAll(dir) defer db.Close() var users []User err := db.All(&users, storm.Limit(2)) if err != nil { log.Fatal(err) } fmt.Println("Found", len(users)) } type User struct { ID int `storm:"id"` Group string `storm:"index"` Email string `storm:"unique"` Name string Age int `storm:"index"` CreatedAt time.Time `storm:"index"` } type Account struct { ID int `storm:"id"` Amount int64 } func prepareDB() (string, *storm.DB) { dir, _ := ioutil.TempDir(os.TempDir(), "storm") db, _ := storm.Open(filepath.Join(dir, "storm.db"), storm.AutoIncrement()) for i, name := range []string{"John", "Eric", "Dilbert"} { email := strings.ToLower(name + "@provider.com") user := User{ Group: "staff", Email: email, Name: name, Age: 21 + i, CreatedAt: time.Now(), } err := db.Save(&user) if err != nil { log.Fatal(err) } } for i := int64(0); i < 10; i++ { account := Account{Amount: 10000} err := db.Save(&account) if err != nil { log.Fatal(err) } } return dir, db }
Found 2
func Skip ¶
Skip sets the number of records to skip
Example ¶
Code:
package main import ( "fmt" "github.com/asdine/storm" "io/ioutil" "log" "os" "path/filepath" "strings" "time" ) func main() { dir, db := prepareDB() defer os.RemoveAll(dir) defer db.Close() var users []User err := db.All(&users, storm.Skip(1)) if err != nil { log.Fatal(err) } fmt.Println("Found", len(users)) } type User struct { ID int `storm:"id"` Group string `storm:"index"` Email string `storm:"unique"` Name string Age int `storm:"index"` CreatedAt time.Time `storm:"index"` } type Account struct { ID int `storm:"id"` Amount int64 } func prepareDB() (string, *storm.DB) { dir, _ := ioutil.TempDir(os.TempDir(), "storm") db, _ := storm.Open(filepath.Join(dir, "storm.db"), storm.AutoIncrement()) for i, name := range []string{"John", "Eric", "Dilbert"} { email := strings.ToLower(name + "@provider.com") user := User{ Group: "staff", Email: email, Name: name, Age: 21 + i, CreatedAt: time.Now(), } err := db.Save(&user) if err != nil { log.Fatal(err) } } for i := int64(0); i < 10; i++ { account := Account{Amount: 10000} err := db.Save(&account) if err != nil { log.Fatal(err) } } return dir, db }
Found 2
func UseDB ¶
UseDB allow Storm to use an existing open Bolt.DB. Warning: storm.DB.Close() will close the bolt.DB instance.
Example ¶
Code:
package main import ( "fmt" "github.com/asdine/storm" "github.com/boltdb/bolt" "io/ioutil" "log" "os" "path/filepath" "time" ) func main() { dir, _ := ioutil.TempDir(os.TempDir(), "storm") defer os.RemoveAll(dir) bDB, err := bolt.Open(filepath.Join(dir, "bolt.db"), 0600, &bolt.Options{Timeout: 10 * time.Second}) if err != nil { log.Fatal(err) } db, _ := storm.Open("", storm.UseDB(bDB)) defer db.Close() err = db.Save(&User{ID: 10}) if err != nil { log.Fatal(err) } var user User err = db.One("ID", 10, &user) fmt.Println(err) } type User struct { ID int `storm:"id"` Group string `storm:"index"` Email string `storm:"unique"` Name string Age int `storm:"index"` CreatedAt time.Time `storm:"index"` }
<nil>
Types ¶
type BucketScanner ¶
type BucketScanner interface { // PrefixScan scans the root buckets for keys matching the given prefix. PrefixScan(prefix string) []Node // PrefixScan scans the buckets in this node for keys matching the given prefix. RangeScan(min, max string) []Node }
A BucketScanner scans a Node for a list of buckets
type DB ¶
type DB struct { // Path of the database file Path string // Bolt is still easily accessible Bolt *bolt.DB // contains filtered or unexported fields }
DB is the wrapper around BoltDB. It contains an instance of BoltDB and uses it to perform all the needed operations
func (*DB) All ¶
All get all the records of a bucket
Example ¶
Code:
package main import ( "fmt" "github.com/asdine/storm" "io/ioutil" "log" "os" "path/filepath" "strings" "time" ) func main() { dir, db := prepareDB() defer os.RemoveAll(dir) defer db.Close() var users []User err := db.All(&users) if err != nil { log.Fatal(err) } fmt.Println("Found", len(users)) } type User struct { ID int `storm:"id"` Group string `storm:"index"` Email string `storm:"unique"` Name string Age int `storm:"index"` CreatedAt time.Time `storm:"index"` } type Account struct { ID int `storm:"id"` Amount int64 } func prepareDB() (string, *storm.DB) { dir, _ := ioutil.TempDir(os.TempDir(), "storm") db, _ := storm.Open(filepath.Join(dir, "storm.db"), storm.AutoIncrement()) for i, name := range []string{"John", "Eric", "Dilbert"} { email := strings.ToLower(name + "@provider.com") user := User{ Group: "staff", Email: email, Name: name, Age: 21 + i, CreatedAt: time.Now(), } err := db.Save(&user) if err != nil { log.Fatal(err) } } for i := int64(0); i < 10; i++ { account := Account{Amount: 10000} err := db.Save(&account) if err != nil { log.Fatal(err) } } return dir, db }
Found 3
func (*DB) AllByIndex ¶
AllByIndex gets all the records of a bucket that are indexed in the specified index
Example ¶
Code:
package main import ( "fmt" "github.com/asdine/storm" "io/ioutil" "log" "os" "path/filepath" "strings" "time" ) func main() { dir, db := prepareDB() defer os.RemoveAll(dir) defer db.Close() var users []User err := db.AllByIndex("CreatedAt", &users) if err != nil { log.Fatal(err) } fmt.Println("Found", len(users)) } type User struct { ID int `storm:"id"` Group string `storm:"index"` Email string `storm:"unique"` Name string Age int `storm:"index"` CreatedAt time.Time `storm:"index"` } type Account struct { ID int `storm:"id"` Amount int64 } func prepareDB() (string, *storm.DB) { dir, _ := ioutil.TempDir(os.TempDir(), "storm") db, _ := storm.Open(filepath.Join(dir, "storm.db"), storm.AutoIncrement()) for i, name := range []string{"John", "Eric", "Dilbert"} { email := strings.ToLower(name + "@provider.com") user := User{ Group: "staff", Email: email, Name: name, Age: 21 + i, CreatedAt: time.Now(), } err := db.Save(&user) if err != nil { log.Fatal(err) } } for i := int64(0); i < 10; i++ { account := Account{Amount: 10000} err := db.Save(&account) if err != nil { log.Fatal(err) } } return dir, db }
Found 3
func (*DB) Begin ¶
Begin starts a new transaction.
Example ¶
Code:
package main
import (
"fmt"
"github.com/asdine/storm"
"io/ioutil"
"log"
"os"
"path/filepath"
"strings"
"time"
)
func main() {
dir, db := prepareDB()
defer os.RemoveAll(dir)
defer db.Close()
// both start out with a balance of 10000 cents
var account1, account2 Account
tx, err := db.Begin(true)
if err != nil {
log.Fatal(err)
}
defer tx.Rollback()
err = tx.One("ID", 1, &account1)
if err != nil {
log.Fatal(err)
}
err = tx.One("ID", 2, &account2)
if err != nil {
log.Fatal(err)
}
account1.Amount -= 1000
account2.Amount += 1000
err = tx.Save(&account1)
if err != nil {
log.Fatal(err)
}
err = tx.Save(&account2)
if err != nil {
log.Fatal(err)
}
tx.Commit()
var account1Reloaded, account2Reloaded Account
err = db.One("ID", 1, &account1Reloaded)
if err != nil {
log.Fatal(err)
}
err = db.One("ID", 2, &account2Reloaded)
if err != nil {
log.Fatal(err)
}
fmt.Println("Amount in account 1:", account1Reloaded.Amount)
fmt.Println("Amount in account 2:", account2Reloaded.Amount)
}
type User struct {
ID int `storm:"id"`
Group string `storm:"index"`
Email string `storm:"unique"`
Name string
Age int `storm:"index"`
CreatedAt time.Time `storm:"index"`
}
type Account struct {
ID int `storm:"id"`
Amount int64
}
func prepareDB() (string, *storm.DB) {
dir, _ := ioutil.TempDir(os.TempDir(), "storm")
db, _ := storm.Open(filepath.Join(dir, "storm.db"), storm.AutoIncrement())
for i, name := range []string{"John", "Eric", "Dilbert"} {
email := strings.ToLower(name + "@provider.com")
user := User{
Group: "staff",
Email: email,
Name: name,
Age: 21 + i,
CreatedAt: time.Now(),
}
err := db.Save(&user)
if err != nil {
log.Fatal(err)
}
}
for i := int64(0); i < 10; i++ {
account := Account{Amount: 10000}
err := db.Save(&account)
if err != nil {
log.Fatal(err)
}
}
return dir, db
}
Amount in account 1: 9000 Amount in account 2: 11000
func (*DB) Bucket ¶
Bucket returns the root bucket name as a slice. In the normal, simple case this will be empty.
func (*DB) Codec ¶
func (s *DB) Codec() codec.MarshalUnmarshaler
Codec returns the EncodeDecoder used by this instance of Storm
func (*DB) CreateBucketIfNotExists ¶
CreateBucketIfNotExists creates the bucket below the current node if it doesn't already exist.
func (*DB) DeleteStruct ¶
DeleteStruct deletes a structure from the associated bucket
Example ¶
Code:
package main import ( "fmt" "github.com/asdine/storm" "io/ioutil" "log" "os" "path/filepath" "strings" "time" ) func main() { dir, db := prepareDB() defer os.RemoveAll(dir) defer db.Close() var user User err := db.One("ID", 1, &user) if err != nil { log.Fatal(err) } err = db.DeleteStruct(&user) fmt.Println(err) } type User struct { ID int `storm:"id"` Group string `storm:"index"` Email string `storm:"unique"` Name string Age int `storm:"index"` CreatedAt time.Time `storm:"index"` } type Account struct { ID int `storm:"id"` Amount int64 } func prepareDB() (string, *storm.DB) { dir, _ := ioutil.TempDir(os.TempDir(), "storm") db, _ := storm.Open(filepath.Join(dir, "storm.db"), storm.AutoIncrement()) for i, name := range []string{"John", "Eric", "Dilbert"} { email := strings.ToLower(name + "@provider.com") user := User{ Group: "staff", Email: email, Name: name, Age: 21 + i, CreatedAt: time.Now(), } err := db.Save(&user) if err != nil { log.Fatal(err) } } for i := int64(0); i < 10; i++ { account := Account{Amount: 10000} err := db.Save(&account) if err != nil { log.Fatal(err) } } return dir, db }
<nil>
func (*DB) Drop ¶
Drop a bucket
Example ¶
Code:
package main
import (
"fmt"
"github.com/asdine/storm"
"io/ioutil"
"log"
"os"
"path/filepath"
"strings"
"time"
)
func main() {
dir, db := prepareDB()
defer os.RemoveAll(dir)
defer db.Close()
var user User
err := db.One("Email", "john@provider.com", &user)
if err != nil {
log.Fatal(err)
}
err = db.Drop("User")
if err != nil {
log.Fatal(err)
}
// One only works for indexed fields.
err = db.One("Email", "john@provider.com", &user)
fmt.Println(err)
}
type User struct {
ID int `storm:"id"`
Group string `storm:"index"`
Email string `storm:"unique"`
Name string
Age int `storm:"index"`
CreatedAt time.Time `storm:"index"`
}
type Account struct {
ID int `storm:"id"`
Amount int64
}
func prepareDB() (string, *storm.DB) {
dir, _ := ioutil.TempDir(os.TempDir(), "storm")
db, _ := storm.Open(filepath.Join(dir, "storm.db"), storm.AutoIncrement())
for i, name := range []string{"John", "Eric", "Dilbert"} {
email := strings.ToLower(name + "@provider.com")
user := User{
Group: "staff",
Email: email,
Name: name,
Age: 21 + i,
CreatedAt: time.Now(),
}
err := db.Save(&user)
if err != nil {
log.Fatal(err)
}
}
for i := int64(0); i < 10; i++ {
account := Account{Amount: 10000}
err := db.Save(&account)
if err != nil {
log.Fatal(err)
}
}
return dir, db
}
not found
func (*DB) Find ¶
func (s *DB) Find(fieldName string, value interface{}, to interface{}, options ...func(q *index.Options)) error
Find returns one or more records by the specified index
Example ¶
Code:
package main import ( "fmt" "github.com/asdine/storm" "io/ioutil" "log" "os" "path/filepath" "strings" "time" ) func main() { dir, db := prepareDB() defer os.RemoveAll(dir) defer db.Close() var users []User err := db.Find("Group", "staff", &users) if err != nil { log.Fatal(err) } fmt.Println("Found", len(users)) } type User struct { ID int `storm:"id"` Group string `storm:"index"` Email string `storm:"unique"` Name string Age int `storm:"index"` CreatedAt time.Time `storm:"index"` } type Account struct { ID int `storm:"id"` Amount int64 } func prepareDB() (string, *storm.DB) { dir, _ := ioutil.TempDir(os.TempDir(), "storm") db, _ := storm.Open(filepath.Join(dir, "storm.db"), storm.AutoIncrement()) for i, name := range []string{"John", "Eric", "Dilbert"} { email := strings.ToLower(name + "@provider.com") user := User{ Group: "staff", Email: email, Name: name, Age: 21 + i, CreatedAt: time.Now(), } err := db.Save(&user) if err != nil { log.Fatal(err) } } for i := int64(0); i < 10; i++ { account := Account{Amount: 10000} err := db.Save(&account) if err != nil { log.Fatal(err) } } return dir, db }
Found 3
func (*DB) From ¶
From returns a new Storm node with a new bucket root. All DB operations on the new node will be executed relative to the given bucket.
Example ¶
Code:
package main import ( "fmt" "github.com/asdine/storm" "io/ioutil" "log" "os" "path/filepath" "strings" "time" ) func main() { dir, db := prepareDB() defer os.RemoveAll(dir) defer db.Close() // Create some sub buckets to partition the data. privateNotes := db.From("notes", "private") workNotes := db.From("notes", "work") err := privateNotes.Save(&Note{ID: "private1", Text: "This is some private text."}) if err != nil { log.Fatal(err) } err = workNotes.Save(&Note{ID: "work1", Text: "Work related."}) if err != nil { log.Fatal(err) } var privateNote, workNote, personalNote Note err = privateNotes.One("ID", "work1", &workNote) // Not found: Wrong bucket. fmt.Println(err) err = workNotes.One("ID", "work1", &workNote) if err != nil { log.Fatal(err) } err = privateNotes.One("ID", "private1", &privateNote) if err != nil { log.Fatal(err) } fmt.Println(workNote.Text) fmt.Println(privateNote.Text) // These can be nested further if needed: personalNotes := privateNotes.From("personal") err = personalNotes.Save(&Note{ID: "personal1", Text: "This is some very personal text."}) if err != nil { log.Fatal(err) } err = personalNotes.One("ID", "personal1", &personalNote) if err != nil { log.Fatal(err) } fmt.Println(personalNote.Text) } type User struct { ID int `storm:"id"` Group string `storm:"index"` Email string `storm:"unique"` Name string Age int `storm:"index"` CreatedAt time.Time `storm:"index"` } type Account struct { ID int `storm:"id"` Amount int64 } type Note struct { ID string `storm:"id"` Text string } func prepareDB() (string, *storm.DB) { dir, _ := ioutil.TempDir(os.TempDir(), "storm") db, _ := storm.Open(filepath.Join(dir, "storm.db"), storm.AutoIncrement()) for i, name := range []string{"John", "Eric", "Dilbert"} { email := strings.ToLower(name + "@provider.com") user := User{ Group: "staff", Email: email, Name: name, Age: 21 + i, CreatedAt: time.Now(), } err := db.Save(&user) if err != nil { log.Fatal(err) } } for i := int64(0); i < 10; i++ { account := Account{Amount: 10000} err := db.Save(&account) if err != nil { log.Fatal(err) } } return dir, db }
not found Work related. This is some private text. This is some very personal text.
func (*DB) One ¶
One returns one record by the specified index
Example ¶
Code:
package main
import (
"fmt"
"github.com/asdine/storm"
"io/ioutil"
"log"
"os"
"path/filepath"
"strings"
"time"
)
func main() {
dir, db := prepareDB()
defer os.RemoveAll(dir)
defer db.Close()
var user User
err := db.One("Email", "john@provider.com", &user)
if err != nil {
log.Fatal(err)
}
// also works on unindexed fields
err = db.One("Name", "John", &user)
if err != nil {
log.Fatal(err)
}
err = db.One("Name", "Jack", &user)
fmt.Println(err)
}
type User struct {
ID int `storm:"id"`
Group string `storm:"index"`
Email string `storm:"unique"`
Name string
Age int `storm:"index"`
CreatedAt time.Time `storm:"index"`
}
type Account struct {
ID int `storm:"id"`
Amount int64
}
func prepareDB() (string, *storm.DB) {
dir, _ := ioutil.TempDir(os.TempDir(), "storm")
db, _ := storm.Open(filepath.Join(dir, "storm.db"), storm.AutoIncrement())
for i, name := range []string{"John", "Eric", "Dilbert"} {
email := strings.ToLower(name + "@provider.com")
user := User{
Group: "staff",
Email: email,
Name: name,
Age: 21 + i,
CreatedAt: time.Now(),
}
err := db.Save(&user)
if err != nil {
log.Fatal(err)
}
}
for i := int64(0); i < 10; i++ {
account := Account{Amount: 10000}
err := db.Save(&account)
if err != nil {
log.Fatal(err)
}
}
return dir, db
}
not found
func (*DB) Prefix ¶
func (s *DB) Prefix(fieldName string, prefix string, to interface{}, options ...func(*index.Options)) error
Prefix returns one or more records whose given field starts with the specified prefix.
func (*DB) PrefixScan ¶
PrefixScan scans the root buckets for keys matching the given prefix.
func (*DB) Range ¶
func (s *DB) Range(fieldName string, min, max, to interface{}, options ...func(*index.Options)) error
Range returns one or more records by the specified index within the specified range
Example ¶
Code:
package main import ( "fmt" "github.com/asdine/storm" "io/ioutil" "log" "os" "path/filepath" "strings" "time" ) func main() { dir, db := prepareDB() defer os.RemoveAll(dir) defer db.Close() var users []User err := db.Range("Age", 21, 22, &users) if err != nil { log.Fatal(err) } fmt.Println("Found", len(users)) } type User struct { ID int `storm:"id"` Group string `storm:"index"` Email string `storm:"unique"` Name string Age int `storm:"index"` CreatedAt time.Time `storm:"index"` } type Account struct { ID int `storm:"id"` Amount int64 } func prepareDB() (string, *storm.DB) { dir, _ := ioutil.TempDir(os.TempDir(), "storm") db, _ := storm.Open(filepath.Join(dir, "storm.db"), storm.AutoIncrement()) for i, name := range []string{"John", "Eric", "Dilbert"} { email := strings.ToLower(name + "@provider.com") user := User{ Group: "staff", Email: email, Name: name, Age: 21 + i, CreatedAt: time.Now(), } err := db.Save(&user) if err != nil { log.Fatal(err) } } for i := int64(0); i < 10; i++ { account := Account{Amount: 10000} err := db.Save(&account) if err != nil { log.Fatal(err) } } return dir, db }
Found 2
func (*DB) Remove ¶
Remove deletes a structure from the associated bucket Deprecated: Use DeleteStruct instead.
func (*DB) Save ¶
Save a structure
Example ¶
Code:
package main import ( "fmt" "github.com/asdine/storm" "io/ioutil" "log" "os" "path/filepath" "time" ) func main() { dir, _ := ioutil.TempDir(os.TempDir(), "storm") defer os.RemoveAll(dir) type User struct { ID int `storm:"id"` Group string `storm:"index"` Email string `storm:"unique"` Name string Age int `storm:"index"` CreatedAt time.Time `storm:"index"` } // Open takes an optional list of options as the last argument. // AutoIncrement will auto-increment integer IDs without existing values. db, _ := storm.Open(filepath.Join(dir, "storm.db"), storm.AutoIncrement()) defer db.Close() user := User{ Group: "staff", Email: "john@provider.com", Name: "John", Age: 21, CreatedAt: time.Now(), } err := db.Save(&user) if err != nil { log.Fatal(err) } fmt.Println(user.ID) user2 := user user2.ID = 0 // Save will fail because of the unique constraint on Email err = db.Save(&user2) fmt.Println(err) }
1 already exists
func (*DB) UpdateField ¶
UpdateField updates a single field
type Finder ¶
type Finder interface { // One returns one record by the specified index One(fieldName string, value interface{}, to interface{}) error // Find returns one or more records by the specified index Find(fieldName string, value interface{}, to interface{}, options ...func(q *index.Options)) error // AllByIndex gets all the records of a bucket that are indexed in the specified index AllByIndex(fieldName string, to interface{}, options ...func(*index.Options)) error // All gets all the records of a bucket. // If there are no records it returns no error and the 'to' parameter is set to an empty slice. All(to interface{}, options ...func(*index.Options)) error // Select a list of records that match a list of matchers. Doesn't use indexes. Select(matchers ...q.Matcher) Query // Range returns one or more records by the specified index within the specified range Range(fieldName string, min, max, to interface{}, options ...func(*index.Options)) error // Prefix returns one or more records whose given field starts with the specified prefix. Prefix(fieldName string, prefix string, to interface{}, options ...func(*index.Options)) error // Count counts all the records of a bucket Count(data interface{}) (int, error) }
A Finder can fetch types from BoltDB
type KeyValueStore ¶
type KeyValueStore interface { // Get a value from a bucket Get(bucketName string, key interface{}, to interface{}) error // Set a key/value pair into a bucket Set(bucketName string, key interface{}, value interface{}) error // Delete deletes a key from a bucket Delete(bucketName string, key interface{}) error // GetBytes gets a raw value from a bucket. GetBytes(bucketName string, key interface{}) ([]byte, error) // SetBytes sets a raw value into a bucket. SetBytes(bucketName string, key interface{}, value []byte) error }
KeyValueStore can store and fetch values by key
type Node ¶
type Node interface { Tx TypeStore KeyValueStore BucketScanner // From returns a new Storm node with a new bucket root below the current. // All DB operations on the new node will be executed relative to this bucket. From(addend ...string) Node // Bucket returns the bucket name as a slice from the root. // In the normal, simple case this will be empty. Bucket() []string // GetBucket returns the given bucket below the current node. GetBucket(tx *bolt.Tx, children ...string) *bolt.Bucket // CreateBucketIfNotExists creates the bucket below the current node if it doesn't // already exist. CreateBucketIfNotExists(tx *bolt.Tx, bucket string) (*bolt.Bucket, error) // WithTransaction returns a New Storm node that will use the given transaction. WithTransaction(tx *bolt.Tx) Node // Begin starts a new transaction. Begin(writable bool) (Node, error) // Codec used by this instance of Storm Codec() codec.MarshalUnmarshaler // WithCodec returns a New Storm Node that will use the given Codec. WithCodec(codec codec.MarshalUnmarshaler) Node // WithBatch returns a new Storm Node with the batch mode enabled. WithBatch(enabled bool) Node }
A Node in Storm represents the API to a BoltDB bucket.
type Query ¶
type Query interface { // Skip matching records by the given number Skip(int) Query // Limit the results by the given number Limit(int) Query // Order by the given fields, in descending precedence, left-to-right. OrderBy(...string) Query // Reverse the order of the results Reverse() Query // Bucket specifies the bucket name Bucket(string) Query // Find a list of matching records Find(interface{}) error // First gets the first matching record First(interface{}) error // Delete all matching records Delete(interface{}) error // Count all the matching records Count(interface{}) (int, error) // Returns all the records without decoding them Raw() ([][]byte, error) // Execute the given function for each raw element RawEach(func([]byte, []byte) error) error // Execute the given function for each element Each(interface{}, func(interface{}) error) error }
Query is the low level query engine used by Storm. It allows to operate searches through an entire bucket.
type Tx ¶
type Tx interface { // Commit writes all changes to disk. Commit() error // Rollback closes the transaction and ignores all previous updates. Rollback() error }
Tx is a transaction
type TypeStore ¶
type TypeStore interface { Finder // Init creates the indexes and buckets for a given structure Init(data interface{}) error // ReIndex rebuilds all the indexes of a bucket ReIndex(data interface{}) error // Save a structure Save(data interface{}) error // Update a structure Update(data interface{}) error // UpdateField updates a single field UpdateField(data interface{}, fieldName string, value interface{}) error // Drop a bucket Drop(data interface{}) error // DeleteStruct deletes a structure from the associated bucket DeleteStruct(data interface{}) error // Remove deletes a structure from the associated bucket // Deprecated: Use DeleteStruct instead. Remove(data interface{}) error }
TypeStore stores user defined types in BoltDB
Source Files
Directories
Path | Synopsis |
---|---|
codec | Package codec contains sub-packages with different codecs that can be used to encode and decode entities in Storm. |
codec/gob | Package gob contains a codec to encode and decode entities in Gob format |
codec/internal | |
codec/json | Package json contains a codec to encode and decode entities in JSON format |
codec/msgpack | Package msgpack contains a codec to encode and decode entities in msgpack format |
codec/protobuf | Package protobuf contains a codec to encode and decode entities in Protocol Buffer Package protobuf is a generated protocol buffer package. |
codec/sereal | Package sereal contains a codec to encode and decode entities using Sereal |
index | Package index contains Index engines used to store values and their corresponding IDs |
internal | |
q | Package q contains a list of Matchers used to compare struct fields with values |