init commit

mod/database/database.go

@@ -0,0 +1,240 @@
+package database
+
+/*
+	ArOZ Online Database Access Module
+	author: tobychui
+
+	This is an improved Object oriented base solution to the original
+	aroz online database script.
+*/
+
+import (
+	"encoding/json"
+	"errors"
+	"log"
+	"sync"
+
+	"github.com/boltdb/bolt"
+)
+
+type Database struct {
+	Db       *bolt.DB
+	Tables   sync.Map
+	ReadOnly bool
+}
+
+func NewDatabase(dbfile string, readOnlyMode bool) (*Database, error) {
+	db, err := bolt.Open(dbfile, 0600, nil)
+	log.Println("Key-value Database Service Started: " + dbfile)
+
+	tableMap := sync.Map{}
+	//Build the table list from database
+	err = db.View(func(tx *bolt.Tx) error {
+		return tx.ForEach(func(name []byte, _ *bolt.Bucket) error {
+			tableMap.Store(string(name), "")
+			return nil
+		})
+	})
+
+	return &Database{
+		Db:       db,
+		Tables:   tableMap,
+		ReadOnly: readOnlyMode,
+	}, err
+}
+
+/*
+	Create / Drop a table
+	Usage:
+	err := sysdb.NewTable("MyTable")
+	err := sysdb.DropTable("MyTable")
+*/
+
+func (d *Database) UpdateReadWriteMode(readOnly bool) {
+	d.ReadOnly = readOnly
+}
+
+//Dump the whole db into a log file
+func (d *Database) Dump(filename string) ([]string, error) {
+	results := []string{}
+
+	d.Tables.Range(func(tableName, v interface{}) bool {
+		entries, err := d.ListTable(tableName.(string))
+		if err != nil {
+			log.Println("Reading table " + tableName.(string) + " failed: " + err.Error())
+			return false
+		}
+		for _, keypairs := range entries {
+			results = append(results, string(keypairs[0])+":"+string(keypairs[1])+"\n")
+		}
+		return true
+	})
+
+	return results, nil
+}
+
+//Create a new table
+func (d *Database) NewTable(tableName string) error {
+	if d.ReadOnly == true {
+		return errors.New("Operation rejected in ReadOnly mode")
+	}
+
+	err := d.Db.Update(func(tx *bolt.Tx) error {
+		_, err := tx.CreateBucketIfNotExists([]byte(tableName))
+		if err != nil {
+			return err
+		}
+		return nil
+	})
+
+	d.Tables.Store(tableName, "")
+	return err
+}
+
+//Check is table exists
+func (d *Database) TableExists(tableName string) bool {
+	if _, ok := d.Tables.Load(tableName); ok {
+		return true
+	}
+	return false
+}
+
+//Drop the given table
+func (d *Database) DropTable(tableName string) error {
+	if d.ReadOnly == true {
+		return errors.New("Operation rejected in ReadOnly mode")
+	}
+
+	err := d.Db.Update(func(tx *bolt.Tx) error {
+		err := tx.DeleteBucket([]byte(tableName))
+		if err != nil {
+			return err
+		}
+		return nil
+	})
+	return err
+}
+
+/*
+	Write to database with given tablename and key. Example Usage:
+	type demo struct{
+		content string
+	}
+	thisDemo := demo{
+		content: "Hello World",
+	}
+	err := sysdb.Write("MyTable", "username/message",thisDemo);
+*/
+func (d *Database) Write(tableName string, key string, value interface{}) error {
+	if d.ReadOnly == true {
+		return errors.New("Operation rejected in ReadOnly mode")
+	}
+
+	jsonString, err := json.Marshal(value)
+	if err != nil {
+		return err
+	}
+	err = d.Db.Update(func(tx *bolt.Tx) error {
+		_, err := tx.CreateBucketIfNotExists([]byte(tableName))
+		b := tx.Bucket([]byte(tableName))
+		err = b.Put([]byte(key), jsonString)
+		return err
+	})
+	return err
+}
+
+/*
+	Read from database and assign the content to a given datatype. Example Usage:
+
+	type demo struct{
+		content string
+	}
+	thisDemo := new(demo)
+	err := sysdb.Read("MyTable", "username/message",&thisDemo);
+*/
+
+func (d *Database) Read(tableName string, key string, assignee interface{}) error {
+	err := d.Db.View(func(tx *bolt.Tx) error {
+		b := tx.Bucket([]byte(tableName))
+		v := b.Get([]byte(key))
+		json.Unmarshal(v, &assignee)
+		return nil
+	})
+	return err
+}
+
+func (d *Database) KeyExists(tableName string, key string) bool {
+	resultIsNil := false
+	err := d.Db.View(func(tx *bolt.Tx) error {
+		b := tx.Bucket([]byte(tableName))
+		v := b.Get([]byte(key))
+		if v == nil {
+			resultIsNil = true
+		}
+		return nil
+	})
+
+	if err != nil {
+		return false
+	} else {
+		if resultIsNil {
+			return false
+		} else {
+			return true
+		}
+	}
+}
+
+/*
+	Delete a value from the database table given tablename and key
+
+	err := sysdb.Delete("MyTable", "username/message");
+*/
+func (d *Database) Delete(tableName string, key string) error {
+	if d.ReadOnly == true {
+		return errors.New("Operation rejected in ReadOnly mode")
+	}
+
+	err := d.Db.Update(func(tx *bolt.Tx) error {
+		tx.Bucket([]byte(tableName)).Delete([]byte(key))
+		return nil
+	})
+
+	return err
+}
+
+/*
+	//List table example usage
+	//Assume the value is stored as a struct named "groupstruct"
+
+	entries, err := sysdb.ListTable("test")
+	if err != nil {
+		panic(err)
+	}
+	for _, keypairs := range entries{
+		log.Println(string(keypairs[0]))
+		group := new(groupstruct)
+		json.Unmarshal(keypairs[1], &group)
+		log.Println(group);
+	}
+
+*/
+
+func (d *Database) ListTable(tableName string) ([][][]byte, error) {
+	var results [][][]byte
+	err := d.Db.View(func(tx *bolt.Tx) error {
+		b := tx.Bucket([]byte(tableName))
+		c := b.Cursor()
+
+		for k, v := c.First(); k != nil; k, v = c.Next() {
+			results = append(results, [][]byte{k, v})
+		}
+		return nil
+	})
+	return results, err
+}
+
+func (d *Database) Close() {
+	d.Db.Close()
+	return
+}

mod/database/doc.txt

@@ -0,0 +1,44 @@
+
+package database // import "imuslab.com/arozos/mod/database"
+
+
+TYPES
+
+type Database struct {
+	Db       *bolt.DB
+	ReadOnly bool
+}
+
+func NewDatabase(dbfile string, readOnlyMode bool) (*Database, error)
+
+func (d *Database) Close()
+
+func (d *Database) Delete(tableName string, key string) error
+    Delete a value from the database table given tablename and key
+
+    err := sysdb.Delete("MyTable", "username/message");
+
+func (d *Database) DropTable(tableName string) error
+
+func (d *Database) KeyExists(tableName string, key string) bool
+
+func (d *Database) ListTable(tableName string) ([][][]byte, error)
+
+func (d *Database) NewTable(tableName string) error
+
+func (d *Database) Read(tableName string, key string, assignee interface{}) error
+
+func (d *Database) UpdateReadWriteMode(readOnly bool)
+
+func (d *Database) Write(tableName string, key string, value interface{}) error
+    Write to database with given tablename and key. Example Usage: type demo
+    struct{
+
+        content string
+
+    } thisDemo := demo{
+
+        content: "Hello World",
+
+    } err := sysdb.Write("MyTable", "username/message",thisDemo);
+