87 lines
2.5 KiB
Go
87 lines
2.5 KiB
Go
/*
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Copyright 2015 github.com/ucirello
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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*/
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// Package dynamolock provides a simple utility for using DynamoDB's consistent
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// read/write feature to use it for managing distributed locks.
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//
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// In order to use this package, the client must create a table in DynamoDB,
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// although the client provides a convenience method for creating that table
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// (CreateTable).
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//
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// Basic usage:
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//
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// import (
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// "log"
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//
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// "cirello.io/dynamolock"
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// "github.com/aws/aws-sdk-go/aws"
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// "github.com/aws/aws-sdk-go/aws/session"
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// "github.com/aws/aws-sdk-go/service/dynamodb"
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// )
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//
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// // ---
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//
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// svc := dynamodb.New(session.Must(session.NewSession(&aws.Config{
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// Region: aws.String("us-west-2"),
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// })))
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// c, err := dynamolock.New(svc,
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// "locks",
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// dynamolock.WithLeaseDuration(3*time.Second),
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// dynamolock.WithHeartbeatPeriod(1*time.Second),
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// )
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// if err != nil {
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// log.Fatal(err)
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// }
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// defer c.Close()
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//
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// log.Println("ensuring table exists")
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// c.CreateTable("locks",
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// dynamolock.WithProvisionedThroughput(&dynamodb.ProvisionedThroughput{
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// ReadCapacityUnits: aws.Int64(5),
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// WriteCapacityUnits: aws.Int64(5),
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// }),
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// dynamolock.WithCustomPartitionKeyName("key"),
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// )
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//
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// data := []byte("some content a")
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// lockedItem, err := c.AcquireLock("spock",
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// dynamolock.WithData(data),
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// dynamolock.ReplaceData(),
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// )
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// if err != nil {
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// log.Fatal(err)
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// }
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//
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// log.Println("lock content:", string(lockedItem.Data()))
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// if got := string(lockedItem.Data()); string(data) != got {
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// log.Println("losing information inside lock storage, wanted:", string(data), " got:", got)
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// }
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//
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// log.Println("cleaning lock")
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// success, err := c.ReleaseLock(lockedItem)
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// if !success {
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// log.Fatal("lost lock before release")
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// }
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// if err != nil {
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// log.Fatal("error releasing lock:", err)
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// }
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// log.Println("done")
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//
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// This package is covered by this SLA:
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// https://github.com/cirello-io/public/blob/master/SLA.md
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//
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package dynamolock // import "cirello.io/dynamolock"
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