Class: Google::Protobuf::Any
- Inherits:
-
Object
- Object
- Google::Protobuf::Any
- Extended by:
- MessageExts::ClassMethods
- Includes:
- MessageExts
- Defined in:
- proto_docs/google/protobuf/any.rb
Overview
Any
contains an arbitrary serialized protocol buffer message along with a
URL that describes the type of the serialized message.
Protobuf library provides support to pack/unpack Any values in the form of utility functions or additional generated methods of the Any type.
Example 1: Pack and unpack a message in C++.
Foo foo = ...;
Any any;
any.PackFrom(foo);
...
if (any.UnpackTo(&foo)) {
...
}
Example 2: Pack and unpack a message in Java.
Foo foo = ...;
Any any = Any.pack(foo);
...
if (any.is(Foo.class)) {
foo = any.unpack(Foo.class);
}
// or ...
if (any.isSameTypeAs(Foo.getDefaultInstance())) {
foo = any.unpack(Foo.getDefaultInstance());
}
Example 3: Pack and unpack a message in Python.
foo = Foo(...)
any = Any()
any.Pack(foo)
...
if any.Is(Foo.DESCRIPTOR):
any.Unpack(foo)
...
Example 4: Pack and unpack a message in Go
foo := &pb.Foo{...}
any, err := anypb.New(foo)
if err != nil {
...
}
...
foo := &pb.Foo{}
if err := any.UnmarshalTo(foo); err != nil {
...
}
The pack methods provided by protobuf library will by default use 'type.googleapis.com/full.type.name' as the type URL and the unpack methods only use the fully qualified type name after the last '/' in the type URL, for example "foo.bar.com/x/y.z" will yield type name "y.z".
JSON
The JSON representation of an Any
value uses the regular
representation of the deserialized, embedded message, with an
additional field @type
which contains the type URL. Example:
package google.profile;
message Person {
string first_name = 1;
string last_name = 2;
}
{
"@type": "type.googleapis.com/google.profile.Person",
"firstName": <string>,
"lastName": <string>
}
If the embedded message type is well-known and has a custom JSON
representation, that representation will be embedded adding a field
value
which holds the custom JSON in addition to the @type
field. Example (for message [google.protobuf.Duration][]):
{
"@type": "type.googleapis.com/google.protobuf.Duration",
"value": "1.212s"
}
Instance Attribute Summary collapse
-
#type_url ⇒ ::String
A URL/resource name that uniquely identifies the type of the serialized protocol buffer message.
-
#value ⇒ ::String
Must be a valid serialized protocol buffer of the above specified type.
Instance Attribute Details
#type_url ⇒ ::String
Returns A URL/resource name that uniquely identifies the type of the serialized
protocol buffer message. This string must contain at least
one "/" character. The last segment of the URL's path must represent
the fully qualified name of the type (as in
path/google.protobuf.Duration
). The name should be in a canonical form
(e.g., leading "." is not accepted).
In practice, teams usually precompile into the binary all types that they
expect it to use in the context of Any. However, for URLs which use the
scheme http
, https
, or no scheme, one can optionally set up a type
server that maps type URLs to message definitions as follows:
- If no scheme is provided,
https
is assumed. - An HTTP GET on the URL must yield a [google.protobuf.Type][] value in binary format, or produce an error.
- Applications are allowed to cache lookup results based on the URL, or have them precompiled into a binary to avoid any lookup. Therefore, binary compatibility needs to be preserved on changes to types. (Use versioned type names to manage breaking changes.)
Note: this functionality is not currently available in the official protobuf release, and it is not used for type URLs beginning with type.googleapis.com. As of May 2023, there are no widely used type server implementations and no plans to implement one.
Schemes other than http
, https
(or the empty scheme) might be
used with implementation specific semantics.
140 141 142 143 |
# File 'proto_docs/google/protobuf/any.rb', line 140 class Any include ::Google::Protobuf::MessageExts extend ::Google::Protobuf::MessageExts::ClassMethods end |