Documentation
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Overview ¶
Provides utility methods to support the converting of structs to bson maps for use in various MongoDB queries/patch updates.
It is intended to be used alongside the Mongo-Go Driver
Index ¶
Constants ¶
This section is empty.
Variables ¶
var ( // By default, this package uses `bson` as the tag name // You can over-write this once you have wrapped your struct // in the mapping struct (StructToBSON) by chaining the // .SetTagName() call on the wrapped struct. DefaultTagName = "bson" )
Functions ¶
func ConvertStructToBSONMap ¶
func ConvertStructToBSONMap(s interface{}, opts *MappingOpts) bson.M
ConvertStructToBSONMap wraps a struct and converts it to a BSON Map, factoring in any options passed as arguments By default, it uses the tag name `bson` on the struct fields to generate the map The mapping is recursive for any data structures contained within the struct
Example StructToBSON to be converted:
type ExampleStruct struct {
Value1 string `bson:"myFirstValue"`
Value2 []int `bson:"myIntSlice"`
}
The struct is first wrapped with the "StructToBSON" type to give access to the mapping functions and is then converted to a bson.M
bson.M {
{ Key: "myFirstValue", Value: "Example String" },
{ Key: "myIntSlice", Value: {1, 2, 3, 4, 5} },
}
The following tag options are factored into the parsing:
// "omitempty" - Omit if the value is the zero value // "omitnested" - Pass the value of the struct directly as opposed to recursively mapping the struct // "flatten" - Pull out the data from the nested struct up one level // "string" - Use the implementation of the Stringer interface for the value // "-" - Do not map this field
Types ¶
type MappingOpts ¶
type MappingOpts struct {
// Will just return bson.M { "_id": idVal } if the "_id" tag is present in that struct,
// if it is not present or holds a zero value it will map the struct as you would expect.
// Setting true on this flag gives it priority over all other functionality.
// ie. If "_id" is present, all other fields will be ignored
//
// This option is included in recursive calls, so if a nested struct
// has an "_id" tag (and the top level struct didn't) then the
// nested struct field in the bson.M will only hold the { "_id": idVal } result.
//
// // Default: False
UseIDifAvailable bool
// Will remove any "_id" fields from your bson.M
// Note: this will remove "_id" fields from nested data structures as well
//
// // Default: False
RemoveID bool
// If true, it will check all struct fields for zero type values and
// omit any that are found regardless of any tag options, effectively it enforces
// the behaviour of the "omitempty" tag, regardless of whether the struct field
// has it or not
//
// This logic occurs after UseIDifAvailable & RemoveID
//
// // Default: False
GenerateFilterOrPatch bool
}
MappingOpts allows the setting of options which drive the behaviour behind how the struct is parsed
type StructToBSON ¶
type StructToBSON struct {
TagName string
// contains filtered or unexported fields
}
StructToBson is the wrapper for a struct that enables this package to work
func NewBSONMapperStruct ¶
func NewBSONMapperStruct(s interface{}) *StructToBSON
NewBSONMapperStruct returns the input struct wrapped by the mapper struct along with the tag name which should be parsed in the mapping
Panics if the argument is not a struct or pointer to a struct
func (*StructToBSON) SetTagName ¶
func (s *StructToBSON) SetTagName(tag string)
SetTagName sets the tag name to be parsed
func (*StructToBSON) ToBSONMap ¶
func (s *StructToBSON) ToBSONMap(opts *MappingOpts) bson.M
ToBSONMap parses all struct fields and returns a bson.M { tagName: value }. If there are nested structs it calls recursively maps them as well
Source Files