span

Documentation

Overview

Package span contains utility functions to interact with the underlying Spanner storage. It does not attempt to encapsulate Spanner.

Index

• func Compress(data []byte) []byte
• func Decompress(src, dest []byte) ([]byte, error)
• func FromSpanner(row *spanner.Row, ptrs ...any) error
• func GenerateStatement(tmpl *template.Template, name string, input any) (spanner.Statement, error)
• func InsertMap(table string, in map[string]any) *spanner.Mutation
• func InsertOrUpdateMap(table string, in map[string]any) *spanner.Mutation
• func QuoteLike(value string) string
• func SpannerDefaultsInterceptor() grpc.UnaryServerInterceptor
• func ToSpanner(v any) any
• func ToSpannerMap(values map[string]any) map[string]any
• func UpdateMap(table string, in map[string]any) *spanner.Mutation
• type Buffer
  • func (b *Buffer) FromSpanner(row *spanner.Row, ptrs ...any) error
• type Compressed
  • func (c *Compressed) FromSpanner(b *Buffer) error
  • func (c *Compressed) SpannerPtr(b *Buffer) any
  • func (c Compressed) ToSpanner() any
• type Ptr
• type Value

Functions

func Compress

func Compress(data []byte) []byte

Compress compresses data using zstd.

func Decompress

func Decompress(src, dest []byte) ([]byte, error)

Decompress decompresses the src compressed with Compress to dest. dest is the buffer for decompressed content, it will be reset to 0 length before taking the content.

func FromSpanner

func FromSpanner(row *spanner.Row, ptrs ...any) error

FromSpanner is a shortcut for (&Buffer{}).FromSpanner. Appropriate when FromSpanner is called only once, whereas Buffer is reusable throughout function.

func GenerateStatement

func GenerateStatement(tmpl *template.Template, name string, input any) (spanner.Statement, error)

GenerateStatement generates a spanner statement from a text template.

func InsertMap

func InsertMap(table string, in map[string]any) *spanner.Mutation

InsertMap is a shortcut for spanner.InsertMap with ToSpannerMap applied to in.

func InsertOrUpdateMap

func InsertOrUpdateMap(table string, in map[string]any) *spanner.Mutation

InsertOrUpdateMap is a shortcut for spanner.InsertOrUpdateMap with ToSpannerMap applied to in.

func QuoteLike

func QuoteLike(value string) string

QuoteLike turns a literal string into an escaped like expression. This means strings like test_name will only match as expected, rather than also matching test3name.

func SpannerDefaultsInterceptor

func SpannerDefaultsInterceptor() grpc.UnaryServerInterceptor

SpannerDefaultsInterceptor returns a gRPC interceptor that adds default Spanner request options to the context.

The request tag will be set the to RPC method name.

See also ModifyRequestOptions in luci/server/span.

func ToSpanner

func ToSpanner(v any) any

ToSpanner converts values from Go types to Spanner types. In addition to supported types in FromSpanner, also supports []any and map[string]any.

func ToSpannerMap

func ToSpannerMap(values map[string]any) map[string]any

ToSpannerMap converts a map of Go values to a map of Spanner values. See also ToSpanner.

func UpdateMap

func UpdateMap(table string, in map[string]any) *spanner.Mutation

UpdateMap is a shortcut for spanner.UpdateMap with ToSpannerMap applied to in.

Types

type Buffer

type Buffer struct {
	NullString  spanner.NullString
	NullTime    spanner.NullTime
	Int64       int64
	StringSlice []string
	ByteSlice   []byte
	Int64Slice  []int64
}

Buffer can convert a value from a Spanner type to a Go type. Supported types:

• Value and Ptr
• string
• timestamppb.Timestamp
• atvpb.Status
• pb.Variant
• pb.StringPair
• proto.Message
• internal.VerdictStatus

func (*Buffer) FromSpanner

func (b *Buffer) FromSpanner(row *spanner.Row, ptrs ...any) error

FromSpanner reads values from row to ptrs, converting types from Spanner to Go along the way.

type Compressed

type Compressed []byte

Compressed instructs ToSpanner and FromSpanner functions to compress the content with https://godoc.org/github.com/klauspost/compress/zstd encoding.

func (*Compressed) FromSpanner

func (c *Compressed) FromSpanner(b *Buffer) error

FromSpanner implements Ptr.

func (*Compressed) SpannerPtr

func (c *Compressed) SpannerPtr(b *Buffer) any

SpannerPtr implements Ptr.

func (Compressed) ToSpanner

func (c Compressed) ToSpanner() any

ToSpanner implements Value.

type Ptr

type Ptr interface {
	// SpannerPtr returns to a pointer of a type supported by Spanner client.
	// SpannerPtr must use one of typed buffers in b.
	SpannerPtr(b *Buffer) any
	// FromSpanner replaces Ptr value with the value in the typed buffer returned
	// by SpannerPtr.
	FromSpanner(b *Buffer) error
}

Ptr can be used a destination of reading a Spanner cell. Typically if type *T implements Ptr, then T implements Value.

type Value

type Value interface {
	// ToSpanner returns a value of a type supported by Spanner client.
	ToSpanner() any
}

Value can be converted to a Spanner value. Typically if type T implements Value, then *T implements Ptr.