db

Documentation

Index

• func ArticlesToProtoArticles(articles []Article) *pb.Articles
• func UnaryClientInterceptor(ctx context.Context, method string, req, reply interface{}, ...) error
• type Article
  • func ProtoArticleToArticle(pbarticle *pb.Article) (article Article)
  • func (u *Article) MarshalBinary() (data []byte, err error)
  • func (u *Article) ProtoArticle() *pb.Article
  • func (u *Article) UnmarshalBinary(data []byte) error
• type ArticleArray
  • func (ua *ArticleArray) MarshalBinary() (data []byte, err error)
  • func (ua *ArticleArray) UnmarshalBinary(data []byte) error
• type DatabaseManager
  • func NewDatabaseManager() (dbm *DatabaseManager, err error)
  • func (dbm *DatabaseManager) GetArticleByID(ctx context.Context, vtspanctx string, ID uint64) (article Article, err error)
  • func (dbm *DatabaseManager) GetArticlesFromRegion(ctx context.Context, vtspanctx string, region int) (articles []Article, err error)
  • func (dbm *DatabaseManager) GetArticlesOfCategory(ctx context.Context, vtspanctx, category string) (articles []Article, err error)
  • func (dbm *DatabaseManager) InsertArticle(article Article) (newID int, err error)
• type MetaDataWriter
  • func (mdw MetaDataWriter) ForeachKey(handler func(key, val string) error) error
  • func (mdw MetaDataWriter) Set(key, val string)

Functions

func ArticlesToProtoArticles

func ArticlesToProtoArticles(articles []Article) *pb.Articles

ArticlesToProtoArticles transforms an array of Articles into an array of pb.Articles which are auto-generated from protobuf.

func UnaryClientInterceptor

func UnaryClientInterceptor(ctx context.Context, method string, req, reply interface{}, cc *grpc.ClientConn, invoker grpc.UnaryInvoker, opts ...grpc.CallOption) error

Types

type Article

type Article struct {
	ID          int64  `json:"id"`
	Timestamp   int64  `json:"timestamp"`
	AID         string `json:"aid"`
	Title       string `json:"title"`
	Category    string `json:"category"`
	Abstract    string `json:"abstract"`
	ArticleTags string `json:"article_tags"`
	Authors     string `json:"authors"`
	Language    string `json:"language"`
	Text        string `json:"text"`
	Image       string `json:"image"`
	Video       string `json:"video"`
}

Article struct refers to the article table of the Vitess MySQl cluster, in the articles keyspace.

func ProtoArticleToArticle

func ProtoArticleToArticle(pbarticle *pb.Article) (article Article)

ProtoArticleToArticle transforms an auto-generated pb.Article from protobuf into the package implementation of Article.

func (*Article) MarshalBinary

func (u *Article) MarshalBinary() (data []byte, err error)

MarshalBinary implements the encoding.BinaryMarshaler interface.

func (*Article) ProtoArticle

func (u *Article) ProtoArticle() *pb.Article

ProtoArticle transforms an Article into a the auto-generated pb.Article structure from protobuf.

func (*Article) UnmarshalBinary

func (u *Article) UnmarshalBinary(data []byte) error

UnmarshalBinary implements the encoding.BinaryUnmarshaler interface.

type ArticleArray

type ArticleArray []Article

ArticleArray represents an array of Article. Implements encoding.BinaryMarshaler and encoding.BinaryUnmarshaler.

func (*ArticleArray) MarshalBinary

func (ua *ArticleArray) MarshalBinary() (data []byte, err error)

MarshalBinary implements the encoding.BinaryMarshaler interface.

func (*ArticleArray) UnmarshalBinary

func (ua *ArticleArray) UnmarshalBinary(data []byte) error

UnmarshalBinary implements the encoding.BinaryUnmarshaler interface.

type DatabaseManager

type DatabaseManager struct {
	// contains filtered or unexported fields
}

DatabaseManager contains the connection pools of the Vitess MySQL cluster. The main connection pool that should be used is the `db *sql.DB` one, the others are just for proof-of-concept-purpose.

func NewDatabaseManager

func NewDatabaseManager() (dbm *DatabaseManager, err error)

NewDatabaseManager will return a newly created DatabaseManager, the DatabaseManager will contain the initialized connection pools to Vitess MySQL cluster.

func (*DatabaseManager) GetArticleByID

func (dbm *DatabaseManager) GetArticleByID(ctx context.Context, vtspanctx string, ID uint64) (article Article, err error)

GetArticleByID will fetch an article from Vitess corresponding to the given unique ID.

func (*DatabaseManager) GetArticlesFromRegion

func (dbm *DatabaseManager) GetArticlesFromRegion(ctx context.Context, vtspanctx string, region int) (articles []Article, err error)

GetArticlesFromRegion is used as an experiment. It queries all the articles that are stored ONLY in the given region ID.

To do such query, the function will not use the default connection pool, instead it will use the shard specific connection pool.

RegionID: 1 = Beijing 2 = Hong Kong

func (*DatabaseManager) GetArticlesOfCategory

func (dbm *DatabaseManager) GetArticlesOfCategory(ctx context.Context, vtspanctx, category string) (articles []Article, err error)

GetArticlesOfCategory will return all the articles belonging to the given category.

func (*DatabaseManager) InsertArticle

func (dbm *DatabaseManager) InsertArticle(article Article) (newID int, err error)

InsertArticle will insert the given Article in Vitess MySQL cluster the new ID will be returned, in addition to an error if there is any.

type MetaDataWriter

type MetaDataWriter struct {
	metadata.MD
}

MetaDataWriter interfaces opentracing.TextMap and is being used to propagate traces to the database cluster.

func (MetaDataWriter) ForeachKey

func (mdw MetaDataWriter) ForeachKey(handler func(key, val string) error) error

ForeachKey implements the Foreach function of opentracing.TextMap interface.

func (MetaDataWriter) Set

func (mdw MetaDataWriter) Set(key, val string)

Set implements the Set function of opentracing.TextMap interface.