149 lines
4.0 KiB
Go
149 lines
4.0 KiB
Go
// Copyright 2012 The Gorilla Authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style
|
|
// license that can be found in the LICENSE file.
|
|
|
|
/*
|
|
Package gorilla/schema fills a struct with form values.
|
|
|
|
The basic usage is really simple. Given this struct:
|
|
|
|
type Person struct {
|
|
Name string
|
|
Phone string
|
|
}
|
|
|
|
...we can fill it passing a map to the Decode() function:
|
|
|
|
values := map[string][]string{
|
|
"Name": {"John"},
|
|
"Phone": {"999-999-999"},
|
|
}
|
|
person := new(Person)
|
|
decoder := schema.NewDecoder()
|
|
decoder.Decode(person, values)
|
|
|
|
This is just a simple example and it doesn't make a lot of sense to create
|
|
the map manually. Typically it will come from a http.Request object and
|
|
will be of type url.Values: http.Request.Form or http.Request.MultipartForm:
|
|
|
|
func MyHandler(w http.ResponseWriter, r *http.Request) {
|
|
err := r.ParseForm()
|
|
|
|
if err != nil {
|
|
// Handle error
|
|
}
|
|
|
|
decoder := schema.NewDecoder()
|
|
// r.PostForm is a map of our POST form values
|
|
err := decoder.Decode(person, r.PostForm)
|
|
|
|
if err != nil {
|
|
// Handle error
|
|
}
|
|
|
|
// Do something with person.Name or person.Phone
|
|
}
|
|
|
|
Note: it is a good idea to set a Decoder instance as a package global,
|
|
because it caches meta-data about structs, and a instance can be shared safely:
|
|
|
|
var decoder = schema.NewDecoder()
|
|
|
|
To define custom names for fields, use a struct tag "schema". To not populate
|
|
certain fields, use a dash for the name and it will be ignored:
|
|
|
|
type Person struct {
|
|
Name string `schema:"name"` // custom name
|
|
Phone string `schema:"phone"` // custom name
|
|
Admin bool `schema:"-"` // this field is never set
|
|
}
|
|
|
|
The supported field types in the destination struct are:
|
|
|
|
* bool
|
|
* float variants (float32, float64)
|
|
* int variants (int, int8, int16, int32, int64)
|
|
* string
|
|
* uint variants (uint, uint8, uint16, uint32, uint64)
|
|
* struct
|
|
* a pointer to one of the above types
|
|
* a slice or a pointer to a slice of one of the above types
|
|
|
|
Non-supported types are simply ignored, however custom types can be registered
|
|
to be converted.
|
|
|
|
To fill nested structs, keys must use a dotted notation as the "path" for the
|
|
field. So for example, to fill the struct Person below:
|
|
|
|
type Phone struct {
|
|
Label string
|
|
Number string
|
|
}
|
|
|
|
type Person struct {
|
|
Name string
|
|
Phone Phone
|
|
}
|
|
|
|
...the source map must have the keys "Name", "Phone.Label" and "Phone.Number".
|
|
This means that an HTML form to fill a Person struct must look like this:
|
|
|
|
<form>
|
|
<input type="text" name="Name">
|
|
<input type="text" name="Phone.Label">
|
|
<input type="text" name="Phone.Number">
|
|
</form>
|
|
|
|
Single values are filled using the first value for a key from the source map.
|
|
Slices are filled using all values for a key from the source map. So to fill
|
|
a Person with multiple Phone values, like:
|
|
|
|
type Person struct {
|
|
Name string
|
|
Phones []Phone
|
|
}
|
|
|
|
...an HTML form that accepts three Phone values would look like this:
|
|
|
|
<form>
|
|
<input type="text" name="Name">
|
|
<input type="text" name="Phones.0.Label">
|
|
<input type="text" name="Phones.0.Number">
|
|
<input type="text" name="Phones.1.Label">
|
|
<input type="text" name="Phones.1.Number">
|
|
<input type="text" name="Phones.2.Label">
|
|
<input type="text" name="Phones.2.Number">
|
|
</form>
|
|
|
|
Notice that only for slices of structs the slice index is required.
|
|
This is needed for disambiguation: if the nested struct also had a slice
|
|
field, we could not translate multiple values to it if we did not use an
|
|
index for the parent struct.
|
|
|
|
There's also the possibility to create a custom type that implements the
|
|
TextUnmarshaler interface, and in this case there's no need to registry
|
|
a converter, like:
|
|
|
|
type Person struct {
|
|
Emails []Email
|
|
}
|
|
|
|
type Email struct {
|
|
*mail.Address
|
|
}
|
|
|
|
func (e *Email) UnmarshalText(text []byte) (err error) {
|
|
e.Address, err = mail.ParseAddress(string(text))
|
|
return
|
|
}
|
|
|
|
...an HTML form that accepts three Email values would look like this:
|
|
|
|
<form>
|
|
<input type="email" name="Emails.0">
|
|
<input type="email" name="Emails.1">
|
|
<input type="email" name="Emails.2">
|
|
</form>
|
|
*/
|
|
package schema
|