protobuf

google. protobuf

Source:

Members

(static, constant) NullValue :number

NullValue is a singleton enumeration to represent the null value for the Value type union.

The JSON representation for NullValue is JSON null.

Properties:
Name Type Description
NULL_VALUE number

Null value.

Source:

(static, constant) NullValue :number

NullValue is a singleton enumeration to represent the null value for the Value type union.

The JSON representation for NullValue is JSON null.

Properties:
Name Type Description
NULL_VALUE number

Null value.

Source:

Type Definitions

Any

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);
}

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 := ptypes.MarshalAny(foo)
 ...
 foo := &pb.Foo{}
 if err := ptypes.UnmarshalAny(any, 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"
}
Properties:
Name Type Description
typeUrl string

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.

Schemes other than http, https (or the empty scheme) might be used with implementation specific semantics.

value Buffer

Must be a valid serialized protocol buffer of the above specified type.

Source:
See:

Any

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);
}

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 := ptypes.MarshalAny(foo)
 ...
 foo := &pb.Foo{}
 if err := ptypes.UnmarshalAny(any, 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"
}
Properties:
Name Type Description
typeUrl string

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.

Schemes other than http, https (or the empty scheme) might be used with implementation specific semantics.

value Buffer

Must be a valid serialized protocol buffer of the above specified type.

Source:
See:

Duration

A Duration represents a signed, fixed-length span of time represented as a count of seconds and fractions of seconds at nanosecond resolution. It is independent of any calendar and concepts like "day" or "month". It is related to Timestamp in that the difference between two Timestamp values is a Duration and it can be added or subtracted from a Timestamp. Range is approximately +-10,000 years.

Examples

Example 1: Compute Duration from two Timestamps in pseudo code.

Timestamp start = ...;
Timestamp end = ...;
Duration duration = ...;

duration.seconds = end.seconds - start.seconds;
duration.nanos = end.nanos - start.nanos;

if (duration.seconds < 0 && duration.nanos > 0) {
  duration.seconds += 1;
  duration.nanos -= 1000000000;
} else if (durations.seconds > 0 && duration.nanos < 0) {
  duration.seconds -= 1;
  duration.nanos += 1000000000;
}

Example 2: Compute Timestamp from Timestamp + Duration in pseudo code.

Timestamp start = ...;
Duration duration = ...;
Timestamp end = ...;

end.seconds = start.seconds + duration.seconds;
end.nanos = start.nanos + duration.nanos;

if (end.nanos < 0) {
  end.seconds -= 1;
  end.nanos += 1000000000;
} else if (end.nanos >= 1000000000) {
  end.seconds += 1;
  end.nanos -= 1000000000;
}

Example 3: Compute Duration from datetime.timedelta in Python.

td = datetime.timedelta(days=3, minutes=10)
duration = Duration()
duration.FromTimedelta(td)

JSON Mapping

In JSON format, the Duration type is encoded as a string rather than an object, where the string ends in the suffix "s" (indicating seconds) and is preceded by the number of seconds, with nanoseconds expressed as fractional seconds. For example, 3 seconds with 0 nanoseconds should be encoded in JSON format as "3s", while 3 seconds and 1 nanosecond should be expressed in JSON format as "3.000000001s", and 3 seconds and 1 microsecond should be expressed in JSON format as "3.000001s".

Properties:
Name Type Description
seconds number

Signed seconds of the span of time. Must be from -315,576,000,000 to +315,576,000,000 inclusive. Note: these bounds are computed from: 60 sec/min * 60 min/hr * 24 hr/day * 365.25 days/year * 10000 years

nanos number

Signed fractions of a second at nanosecond resolution of the span of time. Durations less than one second are represented with a 0 seconds field and a positive or negative nanos field. For durations of one second or more, a non-zero value for the nanos field must be of the same sign as the seconds field. Must be from -999,999,999 to +999,999,999 inclusive.

Source:
See:

Empty

A generic empty message that you can re-use to avoid defining duplicated empty messages in your APIs. A typical example is to use it as the request or the response type of an API method. For instance:

service Foo {
  rpc Bar(google.protobuf.Empty) returns (google.protobuf.Empty);
}

The JSON representation for Empty is empty JSON object {}.

Source:
See:

Empty

A generic empty message that you can re-use to avoid defining duplicated empty messages in your APIs. A typical example is to use it as the request or the response type of an API method. For instance:

service Foo {
  rpc Bar(google.protobuf.Empty) returns (google.protobuf.Empty);
}

The JSON representation for Empty is empty JSON object {}.

Source:
See:

FieldMask

FieldMask represents a set of symbolic field paths, for example:

paths: "f.a"
paths: "f.b.d"

Here f represents a field in some root message, a and b fields in the message found in f, and d a field found in the message in f.b.

Field masks are used to specify a subset of fields that should be returned by a get operation or modified by an update operation. Field masks also have a custom JSON encoding (see below).

Field Masks in Projections

When used in the context of a projection, a response message or sub-message is filtered by the API to only contain those fields as specified in the mask. For example, if the mask in the previous example is applied to a response message as follows:

f {
  a : 22
  b {
    d : 1
    x : 2
  }
  y : 13
}
z: 8

The result will not contain specific values for fields x,y and z (their value will be set to the default, and omitted in proto text output):

f {
  a : 22
  b {
    d : 1
  }
}

A repeated field is not allowed except at the last position of a paths string.

If a FieldMask object is not present in a get operation, the operation applies to all fields (as if a FieldMask of all fields had been specified).

Note that a field mask does not necessarily apply to the top-level response message. In case of a REST get operation, the field mask applies directly to the response, but in case of a REST list operation, the mask instead applies to each individual message in the returned resource list. In case of a REST custom method, other definitions may be used. Where the mask applies will be clearly documented together with its declaration in the API. In any case, the effect on the returned resource/resources is required behavior for APIs.

Field Masks in Update Operations

A field mask in update operations specifies which fields of the targeted resource are going to be updated. The API is required to only change the values of the fields as specified in the mask and leave the others untouched. If a resource is passed in to describe the updated values, the API ignores the values of all fields not covered by the mask.

If a repeated field is specified for an update operation, new values will be appended to the existing repeated field in the target resource. Note that a repeated field is only allowed in the last position of a paths string.

If a sub-message is specified in the last position of the field mask for an update operation, then new value will be merged into the existing sub-message in the target resource.

For example, given the target message:

f {
  b {
    d: 1
    x: 2
  }
  c: [1]
}

And an update message:

f {
  b {
    d: 10
  }
  c: [2]
}

then if the field mask is:

paths: ["f.b", "f.c"]

then the result will be:

f {
  b {
    d: 10
    x: 2
  }
  c: [1, 2]
}

An implementation may provide options to override this default behavior for repeated and message fields.

In order to reset a field's value to the default, the field must be in the mask and set to the default value in the provided resource. Hence, in order to reset all fields of a resource, provide a default instance of the resource and set all fields in the mask, or do not provide a mask as described below.

If a field mask is not present on update, the operation applies to all fields (as if a field mask of all fields has been specified). Note that in the presence of schema evolution, this may mean that fields the client does not know and has therefore not filled into the request will be reset to their default. If this is unwanted behavior, a specific service may require a client to always specify a field mask, producing an error if not.

As with get operations, the location of the resource which describes the updated values in the request message depends on the operation kind. In any case, the effect of the field mask is required to be honored by the API.

Considerations for HTTP REST

The HTTP kind of an update operation which uses a field mask must be set to PATCH instead of PUT in order to satisfy HTTP semantics (PUT must only be used for full updates).

JSON Encoding of Field Masks

In JSON, a field mask is encoded as a single string where paths are separated by a comma. Fields name in each path are converted to/from lower-camel naming conventions.

As an example, consider the following message declarations:

message Profile {
  User user = 1;
  Photo photo = 2;
}
message User {
  string display_name = 1;
  string address = 2;
}

In proto a field mask for Profile may look as such:

mask {
  paths: "user.display_name"
  paths: "photo"
}

In JSON, the same mask is represented as below:

{
  mask: "user.displayName,photo"
}

Field Masks and Oneof Fields

Field masks treat fields in oneofs just as regular fields. Consider the following message:

message SampleMessage {
  oneof test_oneof {
    string name = 4;
    SubMessage sub_message = 9;
  }
}

The field mask can be:

mask {
  paths: "name"
}

Or:

mask {
  paths: "sub_message"
}

Note that oneof type names ("test_oneof" in this case) cannot be used in paths.

Field Mask Verification

The implementation of any API method which has a FieldMask type field in the request should verify the included field paths, and return an INVALID_ARGUMENT error if any path is duplicated or unmappable.

Properties:
Name Type Description
paths Array.<string>

The set of field mask paths.

Source:
See:

FieldMask

FieldMask represents a set of symbolic field paths, for example:

paths: "f.a"
paths: "f.b.d"

Here f represents a field in some root message, a and b fields in the message found in f, and d a field found in the message in f.b.

Field masks are used to specify a subset of fields that should be returned by a get operation or modified by an update operation. Field masks also have a custom JSON encoding (see below).

Field Masks in Projections

When used in the context of a projection, a response message or sub-message is filtered by the API to only contain those fields as specified in the mask. For example, if the mask in the previous example is applied to a response message as follows:

f {
  a : 22
  b {
    d : 1
    x : 2
  }
  y : 13
}
z: 8

The result will not contain specific values for fields x,y and z (their value will be set to the default, and omitted in proto text output):

f {
  a : 22
  b {
    d : 1
  }
}

A repeated field is not allowed except at the last position of a paths string.

If a FieldMask object is not present in a get operation, the operation applies to all fields (as if a FieldMask of all fields had been specified).

Note that a field mask does not necessarily apply to the top-level response message. In case of a REST get operation, the field mask applies directly to the response, but in case of a REST list operation, the mask instead applies to each individual message in the returned resource list. In case of a REST custom method, other definitions may be used. Where the mask applies will be clearly documented together with its declaration in the API. In any case, the effect on the returned resource/resources is required behavior for APIs.

Field Masks in Update Operations

A field mask in update operations specifies which fields of the targeted resource are going to be updated. The API is required to only change the values of the fields as specified in the mask and leave the others untouched. If a resource is passed in to describe the updated values, the API ignores the values of all fields not covered by the mask.

If a repeated field is specified for an update operation, new values will be appended to the existing repeated field in the target resource. Note that a repeated field is only allowed in the last position of a paths string.

If a sub-message is specified in the last position of the field mask for an update operation, then new value will be merged into the existing sub-message in the target resource.

For example, given the target message:

f {
  b {
    d: 1
    x: 2
  }
  c: [1]
}

And an update message:

f {
  b {
    d: 10
  }
  c: [2]
}

then if the field mask is:

paths: ["f.b", "f.c"]

then the result will be:

f {
  b {
    d: 10
    x: 2
  }
  c: [1, 2]
}

An implementation may provide options to override this default behavior for repeated and message fields.

In order to reset a field's value to the default, the field must be in the mask and set to the default value in the provided resource. Hence, in order to reset all fields of a resource, provide a default instance of the resource and set all fields in the mask, or do not provide a mask as described below.

If a field mask is not present on update, the operation applies to all fields (as if a field mask of all fields has been specified). Note that in the presence of schema evolution, this may mean that fields the client does not know and has therefore not filled into the request will be reset to their default. If this is unwanted behavior, a specific service may require a client to always specify a field mask, producing an error if not.

As with get operations, the location of the resource which describes the updated values in the request message depends on the operation kind. In any case, the effect of the field mask is required to be honored by the API.

Considerations for HTTP REST

The HTTP kind of an update operation which uses a field mask must be set to PATCH instead of PUT in order to satisfy HTTP semantics (PUT must only be used for full updates).

JSON Encoding of Field Masks

In JSON, a field mask is encoded as a single string where paths are separated by a comma. Fields name in each path are converted to/from lower-camel naming conventions.

As an example, consider the following message declarations:

message Profile {
  User user = 1;
  Photo photo = 2;
}
message User {
  string display_name = 1;
  string address = 2;
}

In proto a field mask for Profile may look as such:

mask {
  paths: "user.display_name"
  paths: "photo"
}

In JSON, the same mask is represented as below:

{
  mask: "user.displayName,photo"
}

Field Masks and Oneof Fields

Field masks treat fields in oneofs just as regular fields. Consider the following message:

message SampleMessage {
  oneof test_oneof {
    string name = 4;
    SubMessage sub_message = 9;
  }
}

The field mask can be:

mask {
  paths: "name"
}

Or:

mask {
  paths: "sub_message"
}

Note that oneof type names ("test_oneof" in this case) cannot be used in paths.

Field Mask Verification

The implementation of any API method which has a FieldMask type field in the request should verify the included field paths, and return an INVALID_ARGUMENT error if any path is duplicated or unmappable.

Properties:
Name Type Description
paths Array.<string>

The set of field mask paths.

Source:
See:

ListValue

ListValue is a wrapper around a repeated field of values.

The JSON representation for ListValue is JSON array.

Properties:
Name Type Description
values Array.<Object>

Repeated field of dynamically typed values.

This object should have the same structure as Value

Source:
See:

ListValue

ListValue is a wrapper around a repeated field of values.

The JSON representation for ListValue is JSON array.

Properties:
Name Type Description
values Array.<Object>

Repeated field of dynamically typed values.

This object should have the same structure as Value

Source:
See:

Struct

Struct represents a structured data value, consisting of fields which map to dynamically typed values. In some languages, Struct might be supported by a native representation. For example, in scripting languages like JS a struct is represented as an object. The details of that representation are described together with the proto support for the language.

The JSON representation for Struct is JSON object.

Properties:
Name Type Description
fields Object.<string, Object>

Unordered map of dynamically typed values.

Source:
See:

Struct

Struct represents a structured data value, consisting of fields which map to dynamically typed values. In some languages, Struct might be supported by a native representation. For example, in scripting languages like JS a struct is represented as an object. The details of that representation are described together with the proto support for the language.

The JSON representation for Struct is JSON object.

Properties:
Name Type Description
fields Object.<string, Object>

Unordered map of dynamically typed values.

Source:
See:

Value

Value represents a dynamically typed value which can be either null, a number, a string, a boolean, a recursive struct value, or a list of values. A producer of value is expected to set one of that variants, absence of any variant indicates an error.

The JSON representation for Value is JSON value.

Properties:
Name Type Description
nullValue number

Represents a null value.

The number should be among the values of NullValue

numberValue number

Represents a double value.

stringValue string

Represents a string value.

boolValue boolean

Represents a boolean value.

structValue Object

Represents a structured value.

This object should have the same structure as Struct

listValue Object

Represents a repeated Value.

This object should have the same structure as ListValue

Source:
See:

Value

Value represents a dynamically typed value which can be either null, a number, a string, a boolean, a recursive struct value, or a list of values. A producer of value is expected to set one of that variants, absence of any variant indicates an error.

The JSON representation for Value is JSON value.

Properties:
Name Type Description
nullValue number

Represents a null value.

The number should be among the values of NullValue

numberValue number

Represents a double value.

stringValue string

Represents a string value.

boolValue boolean

Represents a boolean value.

structValue Object

Represents a structured value.

This object should have the same structure as Struct

listValue Object

Represents a repeated Value.

This object should have the same structure as ListValue

Source:
See: