Datastore Wrapper

:construction: This package is unstable :construction: github repo

(AppEngine | Cloud) Datastore wrapper for Go 👉

Simple. Happy. Respect standard library.

$ go get -u go.mercari.io/datastore

Feature

DO

• Wrap google.golang.org/appengine/datastore and cloud.google.com/go/datastore
  • keep key behavior
  • align to cloud.google.com/go/datastore first
• Re-implement datastore package
• Re-implement datastore.SaveStruct & LoadStruct
  • Ignore unmapped property
  • Add PropertyTranslator interface
    • Convert types like mytime.Unix to time.Time and reverse it
    • Rename property like CreatedAt to createdAt or created_at and reverse it
• Re-implement PropertyLoadSaver
  • Pass context.Context to Save & Load method
  • It can catch entity from the cache layers as well as from the datastore
• Add retry feature to each RPC
  • e.g. Retry AllocateID when it failed
• Add cache layer
  • About...
    • Local Cache
    • AE Memcache
    • etc...
  • Easy to ON/OFF switching
• Add some useful methods
  • aedatastore/TransactionContext

DON'T

• have utility functions
• support firestore

Restriction

• aedatastore package
  • When using slice of struct, MUST specified datastore:",flatten" option.
    • original (ae & cloud) datastore.SaveStruct have different behaviors.
    • see aeprodtest/main.go /api/test3

How To Use

TODO

Best Practice

TODO

Project Navigation

• aedatastore
  • Datastore Wrapper implementation for AppEngine Datastore
• aeprodtest
  • Test code that works in AppEngine production environment
• boom
  • goon likes interface for this package
• cache
  • Implementation of cache layer strategies
  • cache/aememcache
    • Entity caching with AE Memcache
  • cache/dslog
    • Datastore operation logging in cache layer
  • cache/fishbone
    • Replace query by KeysOnly query with Get ops
  • cache/localcache
    • Entity caching with machine local memory
  • cache/storagecache
    • Entity cacheing base code
• clouddatastore
  • Datastore Wrapper implementation for Cloud Datastore
• internal
  • internal package
• testbed
  • Testbed to check the behavior of AE Datastore and Cloud Datastore
• testsuite
  • Test suite for this package
    • AE Datastore entry point
    • Cloud Datastore entry point

TODO

• Write tests for namespace
• Retry feature
• Write more documents

Committers

• Masahiro Wakame (@vvakame)

Contribution

Please read the CLA below carefully before submitting your contribution.

https://www.mercari.com/cla/

Setup environment & Run tests

• requirements
  • gcloud sdk
    • gcloud components install app-engine-go
    • gcloud components install beta cloud-datastore-emulator
  • dep
    • go get -u github.com/golang/dep/cmd/dep

1. Testing in local

$ ./setup.sh # exec once
$ ./serve.sh # exec in background
$ ./test.sh

2. Testing with Docker

$ ./build-in-docker.sh

3. Testing with Circle CI CLI

$ circleci build

License

Copyright 2017 Mercari, Inc.

Licensed under the MIT License.