megaco_encoder
Data Types
alpha() = 65..90 | 97..122
Alpha Numeric characters: A..Z | a..z
digit() = 48..57
Decimal digits: 0..9
segment_no() = 0..65535
ip4Address() = #'IP4Address'{}
ip6Address() = #'IP6Address'{}
domainName() = #'DomainName'{}
pathName() =
[42 | alpha() | digit() | 95 | 47 | 36 | 64 | 45 | 46]
[42 | alpha() | digit() | 95 | 47 | 36 | 64 | 45 | 46]
There is no way to properly express this type in the Erlang type system, so this is the best we can do. The minimum length is 1 and the maximum length is 64.
Here is the ABNF (copied from the megaco standard) to fill in the blanks:
# Total length of pathNAME must not exceed 64 chars.
pathNAME = ["*"] NAME *("/" / "*"/ ALPHA / DIGIT /"_" / "$" ) ["@" pathDomainName ]
# ABNF allows two or more consecutive "." although it is meaningless in a path domain name.
pathDomainName = (ALPHA / DIGIT / "*" ) *63(ALPHA / DIGIT / "-" / "*" / ".")
NAME = ALPHA *63(ALPHA / DIGIT / "_" )
There is no way to properly express this type in the Erlang type system, so this is the best we can do.
A proper definition would be: -type mtpAddress() :: octet_string(2..4).
megaco_message() = #'MegacoMessage'{}
transaction() =
{transactionRequest, transaction_request()} |
{transactionPending, transaction_reply()} |
{transactionReply, transaction_pending()} |
{transactionResponseAck, transaction_response_ack()} |
{segmentReply, segment_reply()}
{transactionRequest, transaction_request()} |
{transactionPending, transaction_reply()} |
{transactionReply, transaction_pending()} |
{transactionResponseAck, transaction_response_ack()} |
{segmentReply, segment_reply()}
transaction_request() = #'TransactionRequest'{}
transaction_pending() = #'TransactionPending'{}
The problem with TransactionReply is that its definition depend on which version of the protocol we are using. As of version 3, it has two more fields.
transaction_ack() = #'TransactionAck'{}
segment_reply() = #'SegmentReply'{}
action_request() =
{'ActionRequest', term(), term(), term(), term()}
{'ActionRequest', term(), term(), term(), term()}
action_reply() =
{'ActionReply', term(), term(), term(), term()}
{'ActionReply', term(), term(), term(), term()}
command_request() = {'CommandRequest', term(), term(), term()}
error_desc() = #'ErrorDescriptor'{}
DATA TYPES
Note
Note that the actual definition of (some of) these records depend on the megaco protocol version used. For instance, the 'TransactionReply' record has two more fields in version 3, so a simple erlang type definition cannot be made here.
protocol_version() = integer()
segment_no() = integer()
megaco_message() = #'MegacoMessage{}'
transaction() = {transactionRequest, transaction_request()} |
{transactionPending, transaction_reply()} |
{transactionReply, transaction_pending()} |
{transactionResponseAck, transaction_response_ack()} |
{segmentReply, segment_reply()}
transaction_request() = #'TransactionRequest'{}
transaction_pending() = #'TransactionPending'{}
transaction_reply() = #'TransactionReply'{}
transaction_response_ack() = [transaction_ack()]
transaction_ack() = #'TransactionAck'{}
segment_reply() = #'SegmentReply'{}
action_request() = #'ActionRequest'{}
action_reply() = #'ActionReply'{}
command_request() = #'CommandRequest'{}
error_desc() = #'ErrorDescriptor'{}Types
EncodingConfig = list()
Version = integer() | dynamic
Message = megaco_message()
Bin = binary()
Error = term()
Decode a megaco message.
Note that if the Version argument is dynamic, the
decoder should try to figure out the actual version from the
message itself and then use the proper decoder, e.g. version 1.
If on the other hand the Version argument is an integer,
it means that this is the expected version of the message and
the decoder for that version should be used.
Types
EncodingConfig = list()
Version = integer() | dynamic
Message = megaco_message()
Bin = binary()
Error = term()
Perform a minimal decode of a megaco message.
The purpose of this function is to do a minimal decode of Megaco message. A successfull result is a 'MegacoMessage' in which only version and mid has been initiated. This function is used by the megaco_messenger module when the decode_message/3 function fails to figure out the mid (the actual sender) of the message.
Note again that a successfull decode only returns a partially initiated message.
Types
EncodingConfig = list()
Version = integer()
Transaction = transaction()
OK = {ok, Bin}
Bin = binary()
Error = {error, Reason}
Reason = not_implemented | OtherReason
OtherReason = term()
Types
EncodingConfig = list()
Version = integer()
ARs = action_requests()
action_requests() = [action_request()]
OK = {ok, Bin}
Bin = binary()
Error = {error, Reason}
Reason = not_implemented | OtherReason
OtherReason = term()
Encode megaco action requests. This function is called when the user calls the function encode_actions/3. If that function is never used or if the codec cannot support this (the encoding of individual actions), then return with error reason not_implemented.
Types
EncodingConfig = list()
Version = integer()
AR = action_reply()
OK = {ok, Bin}
Bin = binary()
Error = {error, Reason}
Reason = not_implemented | OtherReason
OtherReason = term()
Encode a megaco action reply. If this, for whatever reason, is not supported, the function should return the error reason not_implemented.
This function is used when segmentation has been configured. So, for this to work, this function must be fully supported!