spannertag

Documentation

Overview

Package spannertag exports the Cloud Spanner Go client library's `spanner` struct tag parser for use with the fields cache, so third-party libraries can list struct fields with the exact semantics of cloud.google.com/go/spanner.Row.ToStruct and the *Struct mutation constructors.

Index

• Variables
• func Parser(t reflect.StructTag) (name string, keep bool, other interface{}, err error)
• type Tag

Variables

var Cache = fields.NewCache(Parser, nil, nil)

Cache is a shared fields.Cache built on Parser, the exported counterpart of the client's fieldCache.

Functions

func Parser

func Parser(t reflect.StructTag) (name string, keep bool, other interface{}, err error)

Parser parses the `spanner` struct tag: `spanner:"-"` drops the field; `spanner:"->"` marks it read-only keeping the Go field name; otherwise the tag splits on ";" with the column name first and `->` or case-insensitive `readonly` parts marking the field read-only. It satisfies the parseTag contract of fields.NewCache.

Types

type Tag

type Tag struct {
	// ReadOnly is true if the field should be excluded from writes (read-only).
	ReadOnly bool
}

Tag contains metadata about a struct field's spanner tag. It is stored as the parsed-tag value of each fields.Field listed through Cache or any cache built on Parser.