diameter
Main API of the diameter application.
This module provides the interface with which a user can implement a Diameter node that sends and receives messages using the Diameter protocol as defined in RFC 3588.
Basic usage consists of creating a representation of a locally implemented Diameter node and its capabilities with start_service/2, adding transport capability using add_transport/2 and sending Diameter requests and receiving Diameter answers with call/4. Incoming Diameter requests are communicated as callbacks to a diameter_app(3) callback modules as specified in the service configuration.
Beware the difference between diameter (not capitalised) and Diameter (capitalised). The former refers to the Erlang application named diameter whose main api is defined here, the latter to Diameter protocol in the sense of RFC 3588.
The diameter application must be started before calling most functions in this module.
DATA TYPES
Address()
DiameterIdentity()
Grouped()
OctetString()
Time()
Unsigned32()
UTF8String()
Types corresponding to RFC 3588 AVP Data Formats. Defined in diameter_dict(4).
application_alias() = term()
A name identifying a Diameter application in service configuration. Passed to call/4 when sending requests defined by the application.
application_module() = Mod
| [Mod | ExtraArgs]
| #diameter_callback{}
Mod = atom()
ExtraArgs = list()
A module implementing the callback interface defined in diameter_app(3), along with any extra arguments to be appended to those documented for the interface. Note that extra arguments specific to an outgoing request can be specified to call/4, in which case those are are appended to any module-specific extra arguments.
Specifying a #diameter_callback{}
record allows individual
functions to be configured in place of the usual diameter_app(3) callbacks.
See that module for details.
application_opt()
Options defining a Diameter application. Has one the following types.
{alias, application_alias()}
An unique identifier for the application in the scope of the
service.
Defaults to the value of the dictionary
option if
unspecified.
{dictionary, atom()}
The name of an encode/decode module for the Diameter messages defined by the application. These modules are generated from a specification file whose format is documented in diameter_dict(4).
{module, application_module()}
The callback module with which messages of the Diameter application are handled. See diameter_app(3) for the required interface and semantics.
{state, term()}
The initial callback state.
The prevailing state is passed to some
diameter_app(3)
callbacks, which can then return a new state.
Defaults to the value of the alias
option if unspecified.
{call_mutates_state, true|false}
Specifies whether or not the pick_peer/4
application callback can modify the application state,
Defaults to false
if unspecified.
Note!
pick_peer callbacks are serialized when these are allowed to modify state, which is a potential performance bottleneck. A simple Diameter client may suffer no ill effects from using mutable state but a server or agent that responds to incoming request should probably avoid it.
{answer_errors, callback|report|discard}
Determines the manner in which incoming answer messages containing
decode errors are handled.
If callback
then errors result in a handle_answer/4
callback in the same fashion as for handle_request/3, with
errors communicated in the errors
field of the
#diameter_packet{}
record passed to the callback.
If report
then an answer containing errors is discarded
without a callback and a warning report is written to the log.
If discard
then an answer containing errors is silently
discarded without a callback.
In both the report
and discard
cases the return value
for the call/4 invocation in
question is as if a callback had taken place and returned
{error, failure}
.
Defaults to report
if unspecified.
call_opt()
Options available to call/4 when sending an outgoing Diameter request. Has one of the following types.
{extra, list()}
Extra arguments to append to callbacks to the callback module in question. These are appended to any extra arguments configured on the callback itself. Multiple options append to the argument list.
{filter, peer_filter()}
A filter to apply to the list of available peers before passing them to
the pick_peer/4
callback for the application in question.
Multiple options are equivalent a single all
filter on the
corresponding list of filters.
Defaults to none
.
{timeout, Unsigned32()}
The number of milliseconds after which the request should timeout. Defaults to 5000.
detach
Causes call/4 to return ok
as
soon as the request in
question has been encoded instead of waiting for and returning
the result from a subsequent
handle_answer/4
or handle_error/4
callback.
An invalid option will cause call/4 to fail.
capability()
AVP values sent in outgoing CER or CEA messages during capabilities exchange. Can be configured both on a service and a transport, values specified on the latter taking precedence over any specified on the former. Has one of the following types.
{'Origin-Host', DiameterIdentity()}
{'Origin-Realm', DiameterIdentity()}
{'Host-IP-Address', [Address()]}
An address list is available to the start function of a transport module, which can return a new list for use in the subsequent CER or CEA. Host-IP-Address need not be specified if the transport start function returns an address list.
{'Vendor-Id', Unsigned32()}
{'Product-Name', UTF8String()}
{'Origin-State-Id', Unsigned32()}
Origin-State-Id is optional but will be included in outgoing messages
sent by diameter itself: CER/CEA, DWR/DWA and DPR/DPA.
Setting a value of 0
(zero) is equivalent to not setting a
value as documented in RFC 3588.
The function origin_state_id/0
can be used as to retrieve a value that is computed when the diameter
application is started.
{'Supported-Vendor-Id', [Unsigned32()]}
{'Auth-Application-Id', [Unsigned32()]}
{'Inband-Security-Id', [Unsigned32()]}
Inband-Security-Id defaults to the empty list, which is equivalent to a list containing only 0 (= NO_INBAND_SECURITY). If 1 (= TLS) is specified then TLS is selected if the CER/CEA received from the peer offers it.
{'Acct-Application-Id', [Unsigned32()]}
{'Vendor-Specific-Application-Id', [Grouped()]}
{'Firmware-Revision', Unsigned32()}
Note that each tuple communicates one or more AVP values. It is an error to specify duplicate tuples.
evaluable() = {M,F,A} | fun() | [evaluable() | A]
An expression that can be evaluated as a function in the following sense.
eval([{M,F,A} | T]) ->
apply(M, F, T ++ A);
eval([[F|A] | T]) ->
eval([F | T ++ A]);
eval([F|A]) ->
apply(F, A);
eval(F) ->
eval([F]).
Applying an evaluable()
E
to an argument list A
is meant in the sense of eval([E|A])
.
Warning!
Beware of using fun expressions of the form fun Name/Arity
(not
fun Mod:Name/Arity) in situations in which the fun is not short-lived
and code is to be upgraded at runtime since any processes retaining
such a fun will have a reference to old code.
peer_filter() = term()
A filter passed to call/4 in order to select candidate peers for a pick_peer/4 callback. Has one of the following types.
none
Matches any peer. This is a convenience that provides a filter equivalent to no filter at all.
host
Matches only those peers whose Origin-Host
has the same value
as Destination-Host
in the outgoing request in question,
or any peer if the request does not contain
a Destination-Host
AVP.
realm
Matches only those peers whose Origin-Realm
has the same value
as Destination-Realm
in the outgoing request in question,
or any peer if the request does not contain
a Destination-Realm
AVP.
{host, any|DiameterIdentity()}
Matches only those peers whose Origin-Host
has the
specified value, or all peers if the atom any
.
{realm, any|DiameterIdentity()
Matches only those peers whose Origin-Realm
has the
specified value, or all peers if the atom any
.
{eval, evaluable()}
Matches only those peers for which the specified evaluable()
returns
true
on the connection's diameter_caps
record.
Any other return value or exception is equivalent to false
.
{neg, peer_filter()}
Matches only those peers not matched by the specified filter.
{all, [peer_filter()]}
Matches only those peers matched by each filter in the specified list.
{any, [peer_filter()]}
Matches only those peers matched by at least one filter in the specified list.
An invalid filter is equivalent to {any,[]}
, a filter
that matches no peer.
Note!
The host
and realm
filters examine the
outgoing request as passed to call/4,
assuming that this is a record- or list-valued diameter_app:message()
,
and that the message contains at most one of each AVP.
If this is not the case then the {host|realm, DiameterIdentity()}
filters must be used to achieve the desired result.
An empty DiameterIdentity()
(which should not be typical)
matches all hosts/realms for the purposes of filtering.
Warning!
A host
filter is not typically desirable when setting
Destination-Host since it will remove peer agents from the
candidates list.
service_event() = #diameter_event{}
An event message sent to processes that have subscribed to these using subscribe/1.
The info
field of the event record can have one of the
following types.
{up, Ref, Peer, Config, Pkt}
{up, Ref, Peer, Config}
{down, Ref, Peer, Config}
Ref = transport_ref()
Peer = diameter_app:peer()
Config = {connect|listen, [transport_opt()]}
Pkt = #diameter_packet{}
The RFC 3539 watchdog state machine has
transitioned into (up
) or out of (down
) the OKAY
state.
If a #diameter_packet{}
record is present in an up
event
then there has been a capabilties exchange on a newly established
transport connection and the record contains the received CER or CEA.
Otherwise a connection has reestablished without the loss or
connectivity.
Note that a single up
/down
event for a given peer
corresponds to one peer_up/peer_down
callback for each of the Diameter applications negotiated during
capablilities exchange.
That is, the event communicates connectivity with the
peer as a whole while the callbacks communicate connectivity with
respect to individual Diameter applications.
{reconnect, Ref, Opts}
Ref = transport_ref()
Opts = [transport_opt()]
A connecting transport is attempting to establish/reestablish a transport connection with a peer following reconnect_timer or watchdog_timer expiry.
{closed, Ref, Reason, Config}
Ref = transport_ref()
Config = {connect|listen, [transport_opt()]}
Capabilities exchange has failed.
Reason
can have one of the following types.
{'CER', Result, Caps, Pkt}
Result = ResultCode | {capabilities_cb, CB, ResultCode|discard}
Caps = #diameter_caps{}
Pkt = #diameter_packet{}
ResultCode = integer()
CB = evaluable()
An incoming CER has been answered with the indicated result code or
discarded.
Caps
contains pairs of values for the the local node and remote
peer.
Pkt
contains the CER in question.
In the case of rejection by a capabilities callback, the tuple
contains the rejecting callback.
{'CER', Caps, {ResultCode, Pkt}}
ResultCode = integer()
Caps = #diameter_caps{}
Pkt = #diameter_packet{}
An incoming CER contained errors and has been answered with the
indicated result code.
Caps
contains only values for the the local node.
Pkt
contains the CER in question.
{'CEA', Result, Caps, Pkt}
Result = integer() | atom() | {capabilities_cb, CB, ResultCode|discard}
Caps = #diameter_caps{}
Pkt = #diameter_packet{}
ResultCode = integer()
An incoming CEA has been rejected for the indicated reason.
An integer-valued Result
indicates the result code sent
by the peer.
Caps
contains pairs of values for the the local node and remote
peer.
Pkt
contains the CEA in question.
In the case of rejection by a capabilities callback, the tuple
contains the rejecting callback.
{'CEA', Caps, Pkt}
Caps = #diameter_caps{}
Pkt = #diameter_packet{}
An incoming CEA contained errors and has been rejected.
Caps
contains only values for the the local node.
Pkt
contains the CEA in question.
{watchdog, Ref, PeerRef, {From, To}, Config}
Ref = transport_ref()
PeerRef = diameter_app:peer_ref()
From, To = initial | okay | suspect | down | reopen
Config = {connect|listen, [transport_opt()]}
An RFC 3539 watchdog state machine has changed state.
For forward compatibility, a subscriber should be prepared to receive info fields of forms other than the above.
service_name() = term()
The name of a service as passed to start_service/2 and with which the service is identified. There can be at most one service with a given name on a given node. Note that erlang:make_ref/0 can be used to generate a service name that is somewhat unique.
service_opt()
An option passed to start_service/2.
Can be any capability()
as
well as the following.
{application, [application_opt()]}
Defines a Diameter application supported by the service.
A service must configure one application
for each Diameter
application it intends to support.
For an outgoing Diameter request, the relevant application_alias()
is
passed to call/4, while for an
incoming request the application identifier in the message
header determines the application, the identifier being specified in
the application's dictionary
file.
transport_opt()
An option passed to add_transport/2. Has one of the following types.
{transport_module, atom()}
A module implementing a transport process as defined in diameter_transport(3).
Defaults to diameter_tcp
if unspecified.
Multiple transport_module
and transport_config
options are allowed.
The order of these is significant in this case (and only in this case),
a transport_module
being paired with the first
transport_config
following it in the options list, or the
default value for trailing modules.
Transport starts will be attempted with each of the
modules in order until one establishes a connection within the
corresponding timeout (see below) or all fail.
{transport_config, term()}
{transport_config, term(), Unsigned32()}
A term passed as the third argument to the start/3 function of
the relevant transport_module
in order to start a transport process.
Defaults to the empty list if unspecified.
The 3-tuple form additionally specifies an interval, in milliseconds, after which a started transport process should be terminated if it has not yet established a connection. For example, the following options on a connecting transport request a connection with one peer over SCTP or another (typically the same) over TCP.
{transport_module, diameter_sctp}
{transport_config, SctpOpts, 5000}
{transport_module, diameter_tcp}
{transport_config, TcpOpts}
To listen on both SCTP and TCP, define one transport for each.
{applications, [application_alias()]}
The list of Diameter applications to which the transport should be restricted. Defaults to all applications configured on the service in question. Applications not configured on the service in question are ignored.
{capabilities, [capability()]}
AVP's used to construct outgoing CER/CEA messages. Values take precedence over any specified on the service in question.
Specifying a capability as a transport option may be particularly appropriate for Inband-Security-Id, in case TLS is desired over TCP as implemented by diameter_tcp(3).
{capabilities_cb, evaluable()}
A callback invoked upon reception of CER/CEA during capabilities
exchange in order to ask whether or not the connection should
be accepted.
Applied to the relevant transport_ref()
and the
#diameter_caps{}
record of the connection.
Returning ok
accepts the connection.
Returning integer()
causes an incoming
CER to be answered with the specified Result-Code.
Returning discard
causes an incoming CER to
be discarded.
Returning unknown
is equivalent to returning 3010
,
DIAMETER_UNKNOWN_PEER.
Returning anything but ok
or a 2xxx series result
code causes the transport connection to be broken.
Multiple capabilities_cb
options can be specified, in which
case the corresponding callbacks are applied until either all return
ok
or one does not.
{watchdog_timer, TwInit}
TwInit = Unsigned32()
| {M,F,A}
The RFC 3539 watchdog timer. An integer value is interpreted as the RFC's TwInit in milliseconds, a jitter of ± 2 seconds being added at each rearming of the timer to compute the RFC's Tw. An MFA is expected to return the RFC's Tw directly, with jitter applied, allowing the jitter calculation to be performed by the callback.
An integer value must be at least 6000 as required by RFC 3539. Defaults to 30000 if unspecified.
{reconnect_timer, Tc}
Tc = Unsigned32()
For a connecting transport, the RFC 3588 Tc timer, in milliseconds. Note that this timer determines the frequency with which a transport will attempt to establish a connection with its peer only before an initial connection is established: once there is an initial connection it's watchdog_timer that determines the frequency of reconnection attempts, as required by RFC 3539.
For a listening transport, the timer specifies the time after which a
previously connected peer will be forgotten: a connection after this time is
regarded as an initial connection rather than a reestablishment,
causing the RFC 3539 state machine to pass to state OPEN rather than
REOPEN.
Note that these semantics are not goverened by the RFC and
that a listening transport's reconnect_timer
should be greater
than its peer's Tw plus jitter.
Defaults to 30000 for a connecting transport and 60000 for a listening transport.
Unrecognized options are silently ignored but are returned unmodified by service_info/2 and can be referred to in predicate functions passed to remove_transport/2.
transport_ref() = reference()
An reference returned by add_transport/2 that identifies the configuration.
Functions
add_transport(SvcName, {connect|listen, [Opt]}) -> {ok, Ref} | {error, Reason}
SvcName = service_name()
Opt = transport_opt()
Ref = transport_ref()
Reason = term()
Add transport capability to a service.
The service will start transport processes as required in order to
establish a connection with the peer, either by connecting to the peer
(connect
) or by accepting incoming connection requests
(listen
).
A connecting transport establishes transport connections with at most
one peer, an listening transport potentially with many.
The diameter application takes responsibility for exchanging CER/CEA with the peer. Upon successful completion of capabilities exchange the service calls each relevant application module's peer_up/3 callback after which the caller can exchange Diameter messages with the peer over the transport. In addition to CER/CEA, the service takes responsibility for the handling of DWR/DWA and required by RFC 3539, as well as for DPR/DPA.
The returned reference uniquely identifies the transport within the scope of the service. Note that the function returns before a transport connection has been established.
Note!
It is not an error to add a transport to a service that has not yet been configured: a service can be started after configuring its transports.
call(SvcName, App, Request, [Opt]) -> Answer | ok | {error, Reason}
SvcName = service_name()
App = application_alias()
Request = diameter_app:message()
Answer = term()
Opt = call_opt()
Send a Diameter request message.
App
specifies the Diameter application in which the request is
defined and callbacks to the corresponding callback module
will follow as described below and in diameter_app(3).
Unless the detach
option is specified, the call returns either
when an answer message is received from the peer or an error occurs.
In the answer case, the return value is as returned by a
handle_answer/4
callback.
In the error case, whether or not the error is returned directly
by diameter or from a handle_error/4
callback depends on whether or not the outgoing request is
successfully encoded for transmission to the peer, the cases being
documented below.
If there are no suitable peers, or if
pick_peer/4
rejects them by returning false
, then {error,no_connection}
is returned.
Otherwise pick_peer/4
is followed by a
prepare_request/3
callback, the message is encoded and then sent.
There are several error cases which may prevent an answer from being received and passed to a handle_answer/4 callback:
-
If the initial encode of the outgoing request fails, then the request process fails and
{error,encode}
is returned. -
If the request is successfully encoded and sent but the answer times out then a handle_error/4 callback takes place with
Reason = timeout
. -
If the request is successfully encoded and sent but the service in question is stopped before an answer is received then a handle_error/4 callback takes place with
Reason = cancel
. -
If the transport connection with the peer goes down after the request has been sent but before an answer has been received then an attempt is made to resend the request to an alternate peer. If no such peer is available, or if the subsequent pick_peer/4 callback rejects the candidates, then a handle_error/4 callback takes place with
Reason = failover
. If a peer is selected then a prepare_retransmit/3 callback takes place, after which the semantics are the same as following an initial prepare_request/3 callback. -
If an encode error takes place during retransmission then the request process fails and
{error,failure}
is returned. -
If an application callback made in processing the request fails (pick_peer, prepare_request, prepare_retransmit, handle_answer or handle_error) then either
{error,encode}
or{error,failure}
is returned depending on whether or not there has been an attempt to send the request over the transport.
Note that {error,encode}
is the only return value which
guarantees that the request has not been sent over the
transport connection.
origin_state_id() -> Unsigned32()
Return a reasonable value for use as Origin-State-Id in outgoing messages.
The value returned is the number of seconds since 19680120T031408Z,
the first value that can be encoded as a Diameter Time()
,
at the time the diameter application was started.
remove_transport(SvcName, Pred) -> ok
SvcName = service_name()
Pred = Fun | MFA | transport_ref() | list() | true | false
Fun = fun((transport_ref(), connect|listen, list()) -> boolean())
| fun((transport_ref(), list()) -> boolean())
| fun((list()) -> boolean())
MFA = {atom(), atom(), list()}
Remove previously added transports.
Pred
determines which transports to remove.
An arity-3-valued Pred
removes all transports for which
Pred(Ref, Type, Opts)
returns true
, where Type
and
Opts
are as passed to add_transport/2 and Ref
is
as returned by it.
The remaining forms are equivalent to an arity-3 fun as follows.
Pred = fun(transport_ref(), list()): fun(Ref, _, Opts) -> Pred(Ref, Opts) end
Pred = fun(list()): fun(_, _, Opts) -> Pred(Opts) end
Pred = transport_ref(): fun(Ref, _, _) -> Pred == Ref end
Pred = list(): fun(_, _, Opts) -> [] == Pred -- Opts end
Pred = true: fun(_, _, _) -> true end
Pred = false: fun(_, _, _) -> false end
Pred = {M,F,A}: fun(Ref, Type, Opts) -> apply(M, F, [Ref, Type, Opts | A]) end
Removing a transport causes all associated transport connections to
be broken.
A DPR message with
Disconnect-Cause DO_NOT_WANT_TO_TALK_TO_YOU
will be sent
to each connected peer before disassociating the transport configuration
from the service and terminating the transport upon reception of
DPA or timeout.
service_info(SvcName, Info) -> term()
SvcName = service_name()
Info = Item | [Info]
Item = atom()
Return information about a started service.
Item
can be one of the following.
'Origin-Host'
'Origin-Realm'
'Vendor-Id'
'Product-Name'
'Origin-State-Id'
'Host-IP-Address'
'Supported-Vendor'
'Auth-Application-Id'
'Inband-Security-Id'
'Acct-Application-Id'
'Vendor-Specific-Application-Id'
'Firmware-Revision'
Return a capability value as configured with start_service/2.
applications
Return the list of applications as configured with start_service/2.
capabilities
Return a tagged list of all capabilities values as configured with start_service/2.
transport
Return a list containing one entry for each of the service's transport as configured with add_transport/2. Each entry is a tagged list containing both configuration and information about established peer connections. An example return value with for a client service with Origin-Host "client.example.com" configured with a single transport connected to "server.example.com" might look as follows.
[[{ref,#Ref<0.0.0.93>},
{type,connect},
{options,[{transport_module,diameter_tcp},
{transport_config,[{ip,{127,0,0,1}},
{raddr,{127,0,0,1}},
{rport,3868},
{reuseaddr,true}]}]},
{watchdog,{<0.66.0>,{1346,171491,996448},okay}},
{peer,{<0.67.0>,{1346,171491,999906}}},
{apps,[{0,common}]},
{caps,[{origin_host,{"client.example.com","server.example.com"}},
{origin_realm,{"example.com","example.com"}},
{host_ip_address,{[{127,0,0,1}],[{127,0,0,1}]}},
{vendor_id,{0,193}},
{product_name,{"Client","Server"}},
{origin_state_id,{[],[]}},
{supported_vendor_id,{[],[]}},
{auth_application_id,{[0],[0]}},
{inband_security_id,{[],[0]}},
{acct_application_id,{[],[]}},
{vendor_specific_application_id,{[],[]}},
{firmware_revision,{[],[]}},
{avp,{[],[]}}]},
{port,[{owner,<0.69.0>},
{module,diameter_tcp},
{socket,{{127,0,0,1},48758}},
{peer,{{127,0,0,1},3868}},
{statistics,[{recv_oct,656},
{recv_cnt,6},
{recv_max,148},
{recv_avg,109},
{recv_dvi,19},
{send_oct,836},
{send_cnt,6},
{send_max,184},
{send_avg,139},
{send_pend,0}]}]},
{statistics,[{{{0,258,0},recv},3},
{{{0,258,1},send},3},
{{{0,257,0},recv},1},
{{{0,257,1},send},1},
{{{0,258,0},recv,{'Result-Code',2001}},3},
{{{0,280,1},recv},2},
{{{0,280,0},send},2}]}]]
Here ref
is a transport_ref()
and options
the corresponding transport_opt()
list passed to add_transport/2.
The watchdog
entry shows the state of a connection's RFC 3539 watchdog
state machine.
The peer
entry identifies the diameter_app:peer_ref()
for
which there will have been peer_up callbacks for the
Diameter applications identified by the apps
entry,
common
being the application_alias()
.
The caps
entry identifies the capabilities sent by the local
node and received from the peer during capabilities exchange.
The port
entry displays socket-level information about the
transport connection.
The statistics
entry presents Diameter-level counters,
an entry like {{{0,280,1},recv},2}
saying that the client has
received 2 DWR messages: {0,280,1} = {Application_Id, Command_Code,
R_Flag}
.
Note that watchdog
, peer
, apps
, caps
and port
entries depend on connectivity
with the peer and may not be present.
Note also that the statistics
entry presents values acuumulated
during the lifetime of the transport configuration.
A listening transport presents its information slightly differently
since there may be multiple accepted connections for the same transport_ref()
.
The transport
info returned by a server with a single client
connection might look as follows.
[[{ref,#Ref<0.0.0.61>},
{type,listen},
{options,[{transport_module,diameter_tcp},
{transport_config,[{reuseaddr,true},
{ip,{127,0,0,1}},
{port,3868}]}]},
{accept,[[{watchdog,{<0.56.0>,{1346,171481,226895},okay}},
{peer,{<0.58.0>,{1346,171491,999511}}},
{apps,[{0,common}]},
{caps,[{origin_host,{"server.example.com","client.example.com"}},
{origin_realm,{"example.com","example.com"}},
{host_ip_address,{[{127,0,0,1}],[{127,0,0,1}]}},
{vendor_id,{193,0}},
{product_name,{"Server","Client"}},
{origin_state_id,{[],[]}},
{supported_vendor_id,{[],[]}},
{auth_application_id,{[0],[0]}},
{inband_security_id,{[],[]}},
{acct_application_id,{[],[]}},
{vendor_specific_application_id,{[],[]}},
{firmware_revision,{[],[]}},
{avp,{[],[]}}]},
{port,[{owner,<0.62.0>},
{module,diameter_tcp},
{socket,{{127,0,0,1},3868}},
{peer,{{127,0,0,1},48758}},
{statistics,[{recv_oct,1576},
{recv_cnt,16},
{recv_max,184},
{recv_avg,98},
{recv_dvi,26},
{send_oct,1396},
{send_cnt,16},
{send_max,148},
{send_avg,87},
{send_pend,0}]}]}],
[{watchdog,{<0.72.0>,{1346,171491,998404},initial}}]]},
{statistics,[{{{0,280,0},recv},7},
{{{0,280,1},send},7},
{{{0,258,0},send,{'Result-Code',2001}},3},
{{{0,258,1},recv},3},
{{{0,258,0},send},3},
{{{0,280,1},recv},5},
{{{0,280,0},send},5},
{{{0,257,1},recv},1},
{{{0,257,0},send},1}]}]]
The information presented here is as in the connect
case except
that the client connections are grouped under an accept
tuple.
connections
Return a list containing one entry for every established transport
connection whose watchdog state machine is not in the down
state.
This is a flat view of transport
info which lists only active
connections and for which Diameter-level statistics are accumulated
only for the lifetime of the transport connection.
A return value for the server above might look as follows.
[[{ref,#Ref<0.0.0.61>},
{type,accept},
{options,[{transport_module,diameter_tcp},
{transport_config,[{reuseaddr,true},
{ip,{127,0,0,1}},
{port,3868}]}]},
{watchdog,{<0.56.0>,{1346,171481,226895},okay}},
{peer,{<0.58.0>,{1346,171491,999511}}},
{apps,[{0,common}]},
{caps,[{origin_host,{"server.example.com","client.example.com"}},
{origin_realm,{"example.com","example.com"}},
{host_ip_address,{[{127,0,0,1}],[{127,0,0,1}]}},
{vendor_id,{193,0}},
{product_name,{"Server","Client"}},
{origin_state_id,{[],[]}},
{supported_vendor_id,{[],[]}},
{auth_application_id,{[0],[0]}},
{inband_security_id,{[],[]}},
{acct_application_id,{[],[]}},
{vendor_specific_application_id,{[],[]}},
{firmware_revision,{[],[]}},
{avp,{[],[]}}]},
{port,[{owner,<0.62.0>},
{module,diameter_tcp},
{socket,{{127,0,0,1},3868}},
{peer,{{127,0,0,1},48758}},
{statistics,[{recv_oct,10124},
{recv_cnt,132},
{recv_max,184},
{recv_avg,76},
{recv_dvi,9},
{send_oct,10016},
{send_cnt,132},
{send_max,148},
{send_avg,75},
{send_pend,0}]}]},
{statistics,[{{{0,280,0},recv},62},
{{{0,280,1},send},62},
{{{0,258,0},send,{'Result-Code',2001}},3},
{{{0,258,1},recv},3},
{{{0,258,0},send},3},
{{{0,280,1},recv},66},
{{{0,280,0},send},66},
{{{0,257,1},recv},1},
{{{0,257,0},send},1}]}]]
Note that there may be multiple entries with the same ref
, in
contrast to transport
info.
statistics
Return a {{Counter, Ref}, non_neg_integer()}
list of counter values.
Ref
can be either a transport_ref()
or a diameter_app:peer_ref()
.
Entries for the latter are folded into corresponding entries for the
former as peer connections go down.
Entries for both are removed at remove_transport/2.
The Diameter-level statistics returned by transport
and
connections
info are based upon these entries.
Requesting info for an unknown service causes undefined
to be
returned.
Requesting a list of items causes a tagged list to be
returned.
session_id(Ident) -> OctetString()
Ident = DiameterIdentity()
Return a value for a Session-Id AVP.
The value has the form required by section 8.8 of RFC 3588. Ident should be the Origin-Host of the peer from which the message containing the returned value will be sent.
start() -> ok | {error, Reason}
Start the diameter application.
The diameter application must be started before starting a service.
In a production system this is typically accomplished by a boot
file, not by calling start/0
explicitly.
start_service(SvcName, Options) -> ok | {error, Reason}
SvcName = service_name()
Options = [service_opt()]
Reason = term()
Start a diameter service.
A service defines a locally-implemented Diameter node, specifying the capabilities to be advertised during capabilities exchange. Transports are added to a service using add_transport/2.
Note!
A transport can both override its service's capabilities and restrict its supported Diameter applications so "service = Diameter node as identified by Origin-Host" is not necessarily the case.
stop() -> ok | {error, Reason}
Stop the diameter application.
stop_service(SvcName) -> ok | {error, Reason}
SvcName = service_name()
Reason = term()
Stop a diameter service.
Stopping a service causes all associated transport connections to be broken. A DPR message with be sent as in the case of remove_transport/2.
Note!
Stopping a transport does not remove any associated transports: remove_transport/2 must be called to remove transport configuration.
subscribe(SvcName) -> true
SvcName = service_name()
Subscribe to service_event()
messages from
a service.
It is not an error to subscribe to events from a service that does not yet exist. Doing so before adding transports is required to guarantee the reception of all related events.