Protocol Description

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Table of Contents

• motorcortex.proto

  • ConsoleCmdListMsg

  • ConsoleCmdMsg

  • CreateGroupMsg

  • Error

  • ErrorList

  • GetParameterListMsg

  • GetParameterMsg

  • GetParameterTreeHashMsg

  • GetParameterTreeMsg

  • GetSessionTokenMsg

  • GroupMsg

  • GroupParameterInfo

  • GroupStatusMsg

  • Header

  • LoadMsg

  • LoginMsg

  • LogoutMsg

  • OverwriteParameterMsg

  • ParameterInfo

  • ParameterListMsg

  • ParameterMsg

  • ParameterOffset

  • ParameterTreeHashMsg

  • ParameterTreeMsg

  • ReleaseParameterMsg

  • RemoveGroupMsg

  • RestoreSessionMsg

  • SaveMsg

  • SessionTokenMsg

  • SetParameterListMsg

  • SetParameterMsg

  • StatusMsg

  • DataType

  • ErrorLevel

  • OffsetType

  • ParameterFlag

  • ParameterType

  • Permission

  • StatusCode

  • Unit

  • UserGroup

• Scalar Value Types

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motorcortex.proto

Description of the motorcortex-core message.

All core data types, enumerators and RPC messages are defined here.

Version 1.0.0

ConsoleCmdListMsg

Request to execute a list of commands on the server.

User's request to execute a list of commands on the server (console mode).

Server's reply: StatusMsg, with following status codes:

StatusCode::OK - operation successful,

StatusCode::FAILED - operation failed.

(Note: Currently not implemented).

Field	Type	Label	Description
header	Header	optional	Frame counter and actual time.
cmds	ConsoleCmdMsg	repeated	List of commands

ConsoleCmdMsg

Request to execute command on the server.

User's request to execute a command on the server (console mode).

Server's reply: StatusMsg, with following status codes:

StatusCode::OK - operation successful,

StatusCode::FAILED - operation failed.

(Note: Currently not implemented).

Field	Type	Label	Description
header	Header	optional	Frame counter and actual time.
value	string	required	Console command

CreateGroupMsg

Request to create a publisher group.

User's request to start publishing specified parameters. Several users may subscribe to the same group. This mechanism reduces the load on the server and allows more clients to get frequent updates.

User may choose a scale factor for the publishing rate of the group.

Server's reply: GroupStatusMsg, with following status codes:

StatusCode::OK - operation successful,

StatusCode::FAILED - operation failed.

StatusCode::PERMISSION_DENIED - Permission denied because the user has no access rights.

StatusCode::FAILED_TO_SET_REQUESTED_FRQ - operation successful, but failed to change publisher's frequency, because the group has already existed.

StatusCode::FAILED_TO_DECODE - failed to decode request message.

Field	Type	Label	Description
header	Header	optional	Frame counter and actual time.
frq_divider	uint32	required	Requested frequency divider, to scale down publisher rate.
alias	string	required	Name of the group.
paths	string	repeated	List of the parameters.

Error

Error description.

System type, which describes an error.

Field	Type	Label	Description
timestamp	fixed64	required	System time, when error occurred.
error_number	fixed32	required	Error code.
error_level	fixed32	required	Error level.
subsystem	fixed32	required	Subsystem, for example 1 is 1st actuator of the system.
info	fixed32	required	Additional error code, provided by hardware.

ErrorList

List of errors.

Error messages are sent to the client as a list of N active errors.

Field	Type	Label	Description
errors	Error	repeated	List of active errors.
number_of_errors	fixed32	required	Number of errors in the list.
update_counter	fixed32	required	An update couter changes everytime the list of active errors is updated.

GetParameterListMsg

Request to get a list of parameters with info and values.

Server's reply: ParameterListMsg, with following status codes:

StatusCode::OK - operation successful,

StatusCode::FAILED - operation failed.

StatusCode::PERMISSION_DENIED - Permission denied because user has no access rights.

StatusCode::FAILED_TO_DECODE - failed to decode request message.

Field	Type	Label	Description
header	Header	optional	Frame counter and actual time.
params	GetParameterMsg	repeated	List of requested parameter.

GetParameterMsg

Request to get a parameter info and its value.

Server's reply: ParameterMsg, with following status codes:

StatusCode::OK - operation successful,

StatusCode::FAILED - operation failed.

StatusCode::PERMISSION_DENIED - Permission denied because user has no access rights.

StatusCode::FAILED_TO_DECODE - failed to decode request message.

Field	Type	Label	Description
header	Header	optional	Frame counter and actual time.
path	string	required	Path of the requested parameter.

GetParameterTreeHashMsg

Request to get a parameter tree hash.

Instead of requesting a complete parameter tree, a client might request only a tree hash to compare it against the cached tree to detect if the tree on the server has been changed. The difference between hashes indicates the changes in the tree structure. Note: Changes in parameter values do not result in a different tree hash.

Server's reply: ParameterTreeHashMsg, with following status codes:

StatusCode::OK - operation successful,

StatusCode::FAILED - operation failed.

StatusCode::FAILED_TO_DECODE - failed to decode request message.

Field	Type	Label	Description
header	Header	optional	Frame counter and actual time.

GetParameterTreeMsg

Request to get a parameter tree message

Server's reply: ParameterTreeMsg, with following status codes:

StatusCode::OK - user is logged out,

StatusCode::FAILED - operation failed.

StatusCode::FAILED_TO_DECODE - failed to decode request message.

Field	Type	Label	Description
header	Header	optional	Frame counter and actual time.

GetSessionTokenMsg

Request a session token.

After user is logged-in it can request a session token for re-login.

Server's reply: SessionTokenMsg with the token status code.

Field	Type	Label	Description
header	Header	optional	Frame counter and actual time.

GroupMsg

Group message, used by the publisher. (Note: currently is not used, since publisher is not using protobuf)

Field	Type	Label	Description
header	Header	optional	Frame counter and actual time.
params	ParameterMsg	repeated	List of published parameters.

GroupParameterInfo

Parameters' group information.

This data type represents the subscription information, required to decode parameters from the group message.

Field	Type	Label	Description
index	uint32	required	Index of the subscribed parameter.
offset	uint32	required	Offset in the group message.
size	uint32	required	Size of the parameter.
info	ParameterInfo	required	Parameter information.
status	StatusCode	required	Status code.

GroupStatusMsg

Group package description.

Reply for 'CreateGroupMsg', with the package structure.

Message can have following status codes:

StatusCode::OK - operation successful,

StatusCode::FAILED - operation failed,

StatusCode::PERMISSION_DENIED - Permission denied because user has no access rights.

StatusCode::FAILED_TO_SET_REQUESTED_FRQ - operation successful, but failed to change publisher's frequency, because the group has already existed.

StatusCode::FAILED_TO_DECODE - failed to decode request message.

Field	Type	Label	Description
header	Header	optional	Frame counter and actual time.
id	uint32	required	Unique id of the group.
alias	string	required	Name of the group.
params	GroupParameterInfo	repeated	List of parameters' info.
status	StatusCode	required	Status code.

Header

Generic message header, included in the request/reply messages.

Field	Type	Label	Description
frameCounter	fixed32	required	Frame counter counts number of parameter updates.
timestamp	fixed64	required	Current server time in the format: microseconds from 1 Jan 2000.

LoadMsg

Request to load parameter values from the disk.

User's request to load parameter values from XML file.

Server's reply: StatusMsg, with following status codes:

StatusCode::OK - operation successful,

StatusCode::FAILED - operation failed.

StatusCode::PERMISSION_DENIED - Permission denied because user has no access rights.

StatusCode::USER_LOGGED_IN_NO_CONTROL - User is in read-only mode.

StatusCode::FAILED_TO_OPEN - Failed to create/open a file.

StatusCode::FAILED_TO_DECODE - failed to decode request message.

Field	Type	Label	Description
header	Header	optional	Frame counter and actual time.
path	string	required	Path to config file.
file_name	string	required	File name.

LoginMsg

Login request.

User request to get access to the parameter tree.

Server's reply: StatusMsg, with following status codes:

StatusCode::OK - user is logged in,

StatusCode::READ_ONLY_MODE - user is logged in, read only mode,

StatusCode::WRONG_PASSWORD - login failed, wrong login or password.

StatusCode::FAILED_TO_DECODE - failed to decode request message.

Field	Type	Label	Description
header	Header	optional	Frame counter and actual time.
login	string	required	User's login.
password	string	required	User's password.

LogoutMsg

Logout request.

User request to exit. Logout will happen automatically if user is disconnected.

Server's reply: StatusMsg, with following status codes:

StatusCode::OK - user is logged out,

StatusCode::FAILED - operation failed,

StatusCode::FAILED_TO_DECODE - failed to decode request message.

Field	Type	Label	Description
header	Header	optional	Frame counter and actual time.

OverwriteParameterMsg

Request to overwrite/force a parameter value.

User's request to force a parameter value. For the Input and Parameter types the input value will be overwritten, for the Output type, the output value will be overwritten.

By enabling flag 'activate', overwrite value will be active until the flag is disabled, by ether commanding ReleaseParameterMsg or OverwriteParameterMsg with 'activate' - false.

Server's reply: StatusMsg, with following status codes:

StatusCode::OK - operation successful,

StatusCode::FAILED - operation failed.

StatusCode::PERMISSION_DENIED - Permission denied because user has no access rights.

StatusCode::USER_LOGGED_IN_NO_CONTROL - User is in read-only mode.

StatusCode::WRONG_PARAMETER_PATH - Wrong parameter path.

StatusCode::FAILED_TO_DECODE - failed to decode request message.

Field	Type	Label	Description
header	Header	optional	Frame counter and actual time.
offset	ParameterOffset	optional	Offset of the parameter value.
activate	bool	required	Flag to enable/disable permanent overwrite.
path	string	required	Path of the requested parameter.
value	bytes	required	New values.

ParameterInfo

Parameter information fields.

Active state of the parameter in the tree, including its name, size, data type, io type and active flags.

Field	Type	Label	Description
id	uint32	required	Unique id, assigned by parameter server.
data_type	uint32	required	Tag of the data type.
data_size	uint32	required	Size of one data element.
number_of_elements	uint32	required	Number of the elements.
flags	uint32	required	Parameter flags (overwrite, link etc…).
permissions	uint32	required	Access permissions.
param_type	ParameterType	required	I/O type of the parameter.
group_id	UserGroup	required	Group ID of the owner.
unit	Unit	required	SI unit of the parameter.
path	string	required	Path (including name) of the parameter.

ParameterListMsg

List of parameters with info values.

Reply for 'GetParameterListMsg', with the list of parameters info and values.

Message can have following status codes:

StatusCode::OK - operation successful,

StatusCode::FAILED - operation failed.

StatusCode::PERMISSION_DENIED - Permission denied because user has no access rights.

StatusCode::FAILED_TO_DECODE - failed to decode request message.

Field	Type	Label	Description
header	Header	optional	Frame counter and actual time.
params	ParameterMsg	repeated	List of parameters.
status	StatusCode	required	Status code.

ParameterMsg

Parameter info and its value.

Reply for 'GetParameterMsg', with the parameter info and a value.

Message can have following status codes:

StatusCode::OK - operation successful,

StatusCode::FAILED - operation failed.

StatusCode::PERMISSION_DENIED - Permission denied because user has no access rights.

StatusCode::FAILED_TO_DECODE - failed to decode request message.

Field	Type	Label	Description
value	bytes	required	Parameter value.
header	Header	optional	Frame counter and actual time.
info	ParameterInfo	optional	Parameter information.
status	StatusCode	required	Status code.

ParameterOffset

ParameterOffset description.

An offset can be applied when setting a new value of the parameter array

Field	Type	Label	Description
type	OffsetType	required	Type of the offset. Default: OFFSET_ELEMENTS
offset	uint32	required	Starting point.
length	uint32	required	Length from starting point.

ParameterTreeHashMsg

Parameter tree hash.

Hash of the parameter tree.

Message can have following status codes:

StatusCode::OK - operation successful,

StatusCode::FAILED - operation failed.

StatusCode::FAILED_TO_DECODE - failed to decode request message.

Field	Type	Label	Description
header	Header	optional	Frame counter and actual time.
hash	uint32	required	Hash of the tree.
status	StatusCode	required	Status code.

ParameterTreeMsg

Parameter tree data, which contains information about tree structure and available parameters. Message can have following status codes:

StatusCode::OK - operation successful,

StatusCode::FAILED - operation failed.

StatusCode::FAILED_TO_DECODE - failed to decode request message.

Field	Type	Label	Description
header	Header	optional	Frame counter and actual time.
params	ParameterInfo	repeated	Array with available parameters.
hash	uint32	required	Hash value of the parameter tree stored in 'repeated ParameterInfo params'.
status	StatusCode	required	Status code.

ReleaseParameterMsg

Request to release an overwrite/force.

User's request to cancel overwrite of a parameter value.

Server's reply: StatusMsg, with following status codes:

StatusCode::OK - operation successful,

StatusCode::FAILED - operation failed.

StatusCode::PERMISSION_DENIED - Permission denied because user has no access rights.

StatusCode::USER_LOGGED_IN_NO_CONTROL - User is in read-only mode.

StatusCode::WRONG_PARAMETER_PATH - Wrong parameter path.

StatusCode::FAILED_TO_DECODE - failed to decode request message.

Field	Type	Label	Description
header	Header	optional	Frame counter and actual time.
path	string	required	Path of the requested parameter.

RemoveGroupMsg

Request to remove a publisher group.

User's request to unsubscribe from the group.

Server's reply: StatusMsg, with following status codes:

StatusCode::OK - operation successful,

StatusCode::FAILED - operation failed,

StatusCode::PERMISSION_DENIED - Permission denied because user has no access rights.

StatusCode::FAILED_TO_DECODE - failed to decode request message.

Field	Type	Label	Description
header	Header	optional	Frame counter and actual time.
alias	string	required	Name of the group.

RestoreSessionMsg

Restore session request.

User request to restore the old session to access to the parameter tree.

Server's reply: StatusMsg, with following status codes:

StatusCode::OK - user is logged in,

StatusCode::READ_ONLY_MODE - user is logged in, read only mode,

StatusCode::PERMISSION_DENIED - login failed, token expired,

StatusCode::FAILED - operation failed,

StatusCode::FAILED_TO_DECODE - failed to decode request message.

Field	Type	Label	Description
header	Header	optional	Frame counter and actual time.
token	string	required	Session token.

SaveMsg

Request to save parameter values to the disk.

User's request to save parameter values to XML file.

Server's reply: StatusMsg, with following status codes:

StatusCode::OK - operation successful,

StatusCode::FAILED - operation failed.

StatusCode::PERMISSION_DENIED - Permission denied because user has no access rights.

StatusCode::USER_LOGGED_IN_NO_CONTROL - User is in read-only mode.

StatusCode::FAILED_TO_OPEN - Failed to create/open a file.

StatusCode::FAILED_TO_DECODE - failed to decode request message.

Field	Type	Label	Description
header	Header	optional	Frame counter and actual time.
path	string	required	Path to a config file.
file_name	string	required	File name.i

SessionTokenMsg

Session token.

A token with current session id. The toke is used for re-logging if the connection is lost.

Server's reply: SessionTokenmsg with the token and one of the following status codes:

StatusCode::OK - token is granted,

StatusCode::PERMISSION_DENIED - user has no permission,

StatusCode::FAILED - operation failed,

StatusCode::FAILED_TO_DECODE - failed to decode request message.

Field	Type	Label	Description
header	Header	optional	Frame counter and actual time.
token	string	required	Session token.
status	StatusCode	required	Status code.

SetParameterListMsg

Request to set a list of parameters values.

User's request to update a list of parameters values.

Server's reply: StatusMsg, with following status codes:

StatusCode::OK - operation successful,

StatusCode::FAILED - operation failed.

StatusCode::PERMISSION_DENIED - Permission denied because user has no access rights.

StatusCode::USER_LOGGED_IN_NO_CONTROL - User is in read-only mode.

StatusCode::WRONG_PARAMETER_PATH - Wrong parameter path.

StatusCode::FAILED_TO_DECODE - failed to decode request message.

Field	Type	Label	Description
header	Header	optional	Frame counter and actual time.
params	SetParameterMsg	repeated	List of parameter set messages.

SetParameterMsg

Request to set a parameter value.

User's request to update a parameter value.

Server's reply: StatusMsg, with following status codes:

StatusCode::OK - operation successful,

StatusCode::FAILED - operation failed.

StatusCode::PERMISSION_DENIED - Permission denied because user has no access rights.

StatusCode::USER_LOGGED_IN_NO_CONTROL - User is in read-only mode.

StatusCode::WRONG_PARAMETER_PATH - Wrong parameter path.

StatusCode::FAILED_TO_DECODE - failed to decode request message.

Field	Type	Label	Description
header	Header	optional	Frame counter and actual time.
offset	ParameterOffset	optional	Offset of the parameter value.
path	string	required	Path of the requested parameter.
value	bytes	required	New values has to be encoded according to the data type, which is provided in the parameter info.

StatusMsg

Status code message.

Reply with a status code for various request messages.

Field	Type	Label	Description
header	Header	optional	Frame counter and actual time.
status	StatusCode	required	Return status of the request.

DataType

Available data types.

Data types supported by a parameter server.

User data types can be added after the tag USER_TYPE.

Name	Number	Description
data_type_undefined	0
INT8	1	integer 1 byte
UINT8	2	unsigned integer 1 byte
INT16	3	short int
UINT16	4	unsigned short int
INT32	5	int
UINT32	6	unsigned int
INT64	7	long
UINT64	8	unsigned long
BOOL	9	boolean
FLOAT	257	float
DOUBLE	258	double
CHAR	513	char
STRING	514	C-string
BYTES	1177	bytes array
USER_TYPE	1280	end of the system types

ErrorLevel

Available error levels.

Generic user levels generated by the logic. (Note: Check examples of the state machine.)

Name	Number	Description
error_level_undefined	0
INFO	1	Information message.
WARNING	2	Warning message.
FORCED_DISENGAGE	3	Graceful software stop, caused by a hardware malfunction or a wrong user actions.
SHUTDOWN	4	More abrupt software stop, caused by a hardware malfunction.
EMERGENCY_STOP	5	Abrupt software and hardware stop, caused by a hardware malfunction.

OffsetType

Avaliable offset types.

When setting a parameter value user can specify an offset and length

Name	Number	Description
offset_type_undefined	0
OFFSET_ELEMENTS	1	Offset and length is calculated in the elements. For example update an array starting from the element number 3.
OFFSET_BYTES	2	Offset and length is calculated in bytes.
OFFSET_BITS	3	Offset and length is calculated in bits.

ParameterFlag

System parameter's flag

Parameter can have various system flags, which shows that it is been overwritten or linked. (Note: This list will grow in future)

Name	Number	Description
LINK_IS_ACTIVE	1	Parameter is linked to another parameter.
OVERWRITE_IS_ACTIVE	2	Parameter is being overwritten.

ParameterType

Parameter's IO types.

Each parameter in the tree can be an INPUT, an OUTPUT or a PARAMETER.

PARAMETER type is both an input and output, it can be saved and loaded from the disk.

Value of a parameter with OUTPUT type cannot be set, but can be overwritten (forced). Force operation on the OUTPUT will only change the parameter value on everything that is linked to it. It will NOT change the internal value of the block to which the output belongs.

Name	Number	Description
param_type_undefined	0
INPUT	1	Input parameter.
OUTPUT	16	Output parameter.
PARAMETER	256	Input/output parameter, which is saved and loaded from the disk on request.
PARAMETER_VOLATILE	257	Input/output parameter, which is valotile, not saved or loaded from the disk.
PARAMETER_PERSISTENT	258	Input/output parameter, which is persistent, continuously saved and loaded from the disk.

Permission

Available parameters' permissions. Different users/groups may require access to different and/or protected parts of the parameter tree. Permission flags allow fine-tuning access levels of the groups.

The Motorcortex permissions structure is similar to that of Unix file permissions. Permissions are represented either in symbolic notation or in octal notation. (Note: User rights are not yet implemented, instead use Group rights)

For example:

———- (0000): no permission

-rwx—— (0700): read, write, & execute only for owner (Note: currently not implemented, user group flags instead)

-rwxrwx— (0770): read, write, & execute for owner and group (Note: execute flag is used as a permission to open folders)

-rwxrwxr-x (0775): read, write, & execute for owner and group, read & execute for all others.

-rwxrwxrwx (0777): full access

Name	Number	Description
permission_undefined	0
USER_READ	256	owner user read -r——–
USER_WRITE	128	owner user write –w——-
USER_EXECUTE	64	owner user execute —e——
GROUP_READ	32	owner group read —-r—–
GROUP_WRITE	16	owner group write —–w—-
GROUP_EXECUTE	8	owner group execute ——e—
OTHERS_READ	4	other users read ——-r–
OTHERS_WRITE	2	other users write ——–w-
OTHERS_EXECUTE	1	other users ———e

StatusCode

Return status codes.

Return status codes are included in the reply for every user's request. Using these codes user can verify if request was successful or there was a failure.

Name	Number	Description
OK	0	Request was processed successfully.
READ_ONLY_MODE	1	Login is successful, but user has read-only right.
FAILED	65280	Generic failure mask.
FAILED_TO_DECODE	4096	Failed to decode request message.
SUB_LIST_IS_FULL	4352	Failed to subscribe for a parameter, because subscription list is full. Create new parameter group.
WRONG_PARAMETER_PATH	4608	Failed to find parameter, because requested path is wrong.
FAILED_TO_SET_REQUESTED_FRQ	4864	When several clients share the same publisher's group, original publishing frequency is preserved.
FAILED_TO_OPEN_FILE	5120	Failed to open/save/load a file.
WRONG_PASSWORD	8448	Login failed, wrong login or password.
USER_NOT_LOGGED_IN	8704	Operation not permitted, because user is not logged in.
PERMISSION_DENIED	8960	Permission denied because user has no access rights.

Unit

Some SI units.

Name	Number	Description
unit_undefined	0
Length	15	Length mask 0xf
mm	1	millimeters 0x1
m	2	meters 0x2
Angle	241	Angle mask 0xf1
rad	49	radians 0x31
deg	65	degrees 0x41
Time	242	Time mask 0xf2
nanosec	18	nanoseconds 0x12
microsec	34	microseconds 0x22
millisec	50	milliseconds 0x32
sec	66	seconds 0x42
Weight	243	Weight mask 0xf3
gram	19	grams 0x13
kg	35	kilograms 0x23
Velocity	244	Velocity mask 0xf4
m_sec	20	linear velocity, meters per second 0x14
rad_sec	36	angular velocity, radians per second 0x24
Acceleration	245	Acceleration mask 0xf5
m_sec2	21	linear acceleration meters per second^2 0x15
rad_sec2	37	angular acceleration radians per second^2 0x25
Force	246	Force mask 0xf6
N	22	force, newtons 0x16
Nm	38	torque, newton-metres 0x26
percent	23	percentages 0x17

UserGroup

Available user groups.

Group determines an access level of the user. Users can belong to one group: Administrator, Operator or Guest. System is reserved for internal motorcortex-core use. By default Operator cannot read or write Administrator's related parameters. The administrator has a full access to the Operator's data.

Group access can be reconfigured in C++ server code or in the server configuration file. Furthermore, parameterization of the access can be done by setting permission level (Permission) of the parameter.

Name	Number	Description
user_group_undefined	0
SYSTEM	1	System group has full access. It is not available for the users.
ADMINISTRATOR	3	Administrator group has full access, except for system-level parameters.
OPERATOR	7	Operator has limited write access and read access.
GUEST	2147483647	Guest has read access.

Scalar Value Types

.proto Type	Notes	C++	Java	Python	Go	C#	PHP	Ruby
double		double	double	float	float64	double	float	Float
float		float	float	float	float32	float	float	Float
int32	Uses variable-length encoding. Inefficient for encoding negative numbers – if your field is likely to have negative values, use sint32 instead.	int32	int	int	int32	int	integer	Bignum or Fixnum (as required)
int64	Uses variable-length encoding. Inefficient for encoding negative numbers – if your field is likely to have negative values, use sint64 instead.	int64	long	int/long	int64	long	integer/string	Bignum
uint32	Uses variable-length encoding.	uint32	int	int/long	uint32	uint	integer	Bignum or Fixnum (as required)
uint64	Uses variable-length encoding.	uint64	long	int/long	uint64	ulong	integer/string	Bignum or Fixnum (as required)
sint32	Uses variable-length encoding. Signed int value. These more efficiently encode negative numbers than regular int32s.	int32	int	int	int32	int	integer	Bignum or Fixnum (as required)
sint64	Uses variable-length encoding. Signed int value. These more efficiently encode negative numbers than regular int64s.	int64	long	int/long	int64	long	integer/string	Bignum
fixed32	Always four bytes. More efficient than uint32 if values are often greater than 2^28.	uint32	int	int	uint32	uint	integer	Bignum or Fixnum (as required)
fixed64	Always eight bytes. More efficient than uint64 if values are often greater than 2^56.	uint64	long	int/long	uint64	ulong	integer/string	Bignum
sfixed32	Always four bytes.	int32	int	int	int32	int	integer	Bignum or Fixnum (as required)
sfixed64	Always eight bytes.	int64	long	int/long	int64	long	integer/string	Bignum
bool		bool	boolean	boolean	bool	bool	boolean	TrueClass/FalseClass
string	A string must always contain UTF-8 encoded or 7-bit ASCII text.	string	String	str/unicode	string	string	string	String (UTF-8)
bytes	May contain any arbitrary sequence of bytes.	string	ByteString	str	[]byte	ByteString	string	String (ASCII-8BIT)