Experiments with C# sockets.
- Text-based
- Message look like:
Sam-John-Amrit-Melissa;*|ECHO!VALUE:::"PING"- or generally:
Source;Destination|NodeControl|Key:val,Key:val - NodeControl is the type of message (see below)
This is documented in the NodeControl enum, but reproduced here with some extra detail.
MAY: Nodes can choose to implement this or not but should always accept valid messages even if some information is ignored
SHOULD: Nodes can opt not to do this, but it is encouraged. Vice-versa for SHOULD NOT.
MUST: Nodes must implement this to be spec-compliant. Vice-versa for MUST NOT
All messages MAY include an ID arg and/or a REF arg. IDs MUST be GUIDS and REFs MUST refer to a previously sent message's ID which was addressed to the node.
Message source MUST be set to the sending node's name.
Destination SHOULD be a node name or * for a global message to all nodes, unless otherwise limited by the message type.
/*
100-199: Informational messages
200-299: Requests
900-999: Errors
*/
/// <summary>
/// General informational message
/// MAY include args of key:::val pairs of other information
/// When used a a response to a request (2*) message:::
/// MUST include arg - REQUEST:::[NodeControl] of original request
/// </summary>
INFO = 100,
/// <summary>
/// Notification that a request will not be fulfilled
/// MUST NOT be used as a response to unimplemented controls
/// MUST include arg - REQUEST:::[type of original request]
/// MUST include arg- REASON
/// </summary>
DENIAL = 101,
/// <summary>
/// Message to notify all nodes a node is alive
/// MUST set destination to *
/// MAY send arg - "UPTIME:::[node uptime]"
/// Nodes SHOULD periodically send ALIVE messages
/// Nodes MUST send an initial ALIVE message when they join a network
/// </summary>
ALIVE = 102,
/// <summary>
/// Message containing the current time of a node
/// MUST include arg - TIME:::[current time]
/// MAY include arg - ZONE:::[time-zone]
/// </summary>
TIME_SYNC = 103,
/// <summary>
/// Message containing the old name of a node
/// MUST include arg - OLDNAME:::[old node name]
/// </summary>
NAME_CHANGE = 104,
/// <summary>
/// Message notifying of connectivity to a given remote with a given method
/// MUST set arg - REMOTE:::[remote address]
/// MUST set arg - METHOD:::[method of connection] eg, HTTP
/// MUST set arg - REACHABLE:::[true|false]
/// </summary>
CONNECTIVITY_SYNC = 105,
/// <summary>
/// Message notifying of a node disconnecting from the network
/// MAY set arg - WILLWAIT:::[time to disconnect], eg WILLWAIT:2m1s
/// Nodes MAY send updated DISCONNECTING messages with new WILLWAIT estimates
/// Nodes that set arg WILLWAIT MUST stay connected for at least that long unless they send an updated WILLWAIT estimate
/// Nodes sending DISCONNECTING messages without WILLWAIT arg SHOULD stay connected for a short time after to recieve any final replies
/// Nodes that reply to DISCONNECTING messages SHOULD prioritise replies to these messages based on the WILLWAIT arg
/// </summary>
DISCONNECTING = 106,
/// <summary>
/// Request to send node name
/// </summary>
NAME = 200,
/// <summary>
/// Request for node version
/// </summary>
VERSION = 201,
/// <summary>
/// Request for node time
/// </summary>
TIME = 202,
/// <summary>
/// Request for a node to check connectivity to a remote location
/// MUST include arg - REMOTE:::[remote address]
/// MUST include arg - METHOD:::[method to use]
/// Method to use eg, HTTP, HTTPS, PING
/// Responder MUST respond with CONNECTIVITY_SYNC
/// </summary>
CONNECTIVITY = 203,
/// <summary>
/// Request of a node to forward a message
/// MUST NOT set destination as *
/// Node MAY NOT send if final relay destination is that node
/// Node MAY forward via another node
/// MUST include arg - TO:::[final destination]
/// MUST include arg - MESSAGE:::[message to forward]
/// The forwarding message is any valid string representation of a message eg,
/// Damico-Amrit-Valeri-Merrissa;*|TIME!ZONE:::+0
/// Forwarded message MAY be itself a RELAY message
/// </summary>
RELAY = 204,
/// <summary>
/// Request for node to echo given args
/// MUST NOT set destination as *
/// MAY set arg - VALUE:::[any value]
/// MAY set any args
/// Responder MUST echo VALUE
/// Responder MAY echo other args
/// Responder MUST NOT echo args ID or REF
/// </summary>
ECHO = 205,
/// <summary>
/// Notify of a node-specific service that is available
/// MUST send a different message for each available service
/// MUST notify when a service becomes newly available
/// SHOULD periodically notify therafter
/// For standard services (3*)
/// MUST set arg - MESSAGE:::[type of message]
/// MAY set arg - ARGS:::[required arg types and descriptions]
/// MAY set arg - DESCRIPTION:::[description of service]
/// MAY set arg - VERSION:::[version of the advertised service]
/// For non-standard services (4*/5*):
/// MUST set arg - DESCRIPTION:::[description of service]
/// MUST set arg - MESSAGE:::[new type of message to use and its number]
/// MUST set arg - ARGS:::[required arg types and descriptions]
/// MUST set arg - VERSION:::[version of the advertised service]
/// </summary>
SERVICE = 300,
/// <summary>
/// Request for a node to store some data for a given amount of time
/// Nodes using and advertising this service MUST support REF
/// For GET
/// MUST set arg - OP:::[GET/SET]
/// MUST set arg - PATH:::[path to data], eg logs/temperature/12011995-12:30:22
/// Responder MUST respond with INFO
/// MUST set arg - VALUE:::[value or empty for missing value]
/// FOR SET
/// MUST set arg - VALUE:::[value to store]
/// MUST set arg - PATH:::[path to data], eg logs/temperature/12011995-12:30:22
/// SHOULD be relative path, other node decides root
/// MUST NOT contain characters not allowed in a file path
/// MAY set arg - UNTIL:::[when the data may be deleted]
/// If unset, default is forever
/// Formats: 1y2m3d5h2s, MEM (until node closes)
/// Responder must explicitly confirm or deny the addition
/// For deny:
/// MUST use DENIAL/101
/// MUST set arg REF:::[request ref]
/// MUST set arg REASON::[reason]
/// - NO-DATA - invalid path, empty data
/// - SIZE - stored data is too large to send
/// - UNTIL - requested store time is too long/too short
/// - Unathorised - the node requires authorisation
/// MAY set arg - REASONDESCRIPTION:::[Human-readable reason]
/// For confirm SET:
/// MUST use INFO/100
/// MUST set arg - STORED:::[path]
/// MAY set arg - UNTIL:::[until]
/// UNTIL MAY or MAY NOT match requested UNTIL but MUST be at least as long as the request, otherwise MUST deny
/// For confirm GET:
/// MUST use INFO/100
/// MUST set arg - VALUE:::[path]
/// </summary>
STORE = 301,
/// <summary>
/// Request from one node to another to stop sending messages
/// </summary>
CLOSE = 299,
/// <summary>
/// Notification that a previous request is not implemented
/// MUST include arg REQUEST:::[original request]
/// Original request MAY be a NodeControl or MAY be a NodeControl;Subset eg, CONNECTIVITY;HTTP
/// </summary>
NOT_IMPLEMENTED = 900,
/// <summary>
/// Notification that a node has determined that more than one node has the same name
/// MUST set destination as *
/// MUST set arg - NAME:::[clashing name]
/// Nodes recieving a NAME_CLASH whose name is clashing must select a new name
/// </summary>
NAME_CLASH = 901,
/// <summary>
/// Notification that a message was recieved and the sender could be parsed, but the contents of the message could not be handled
/// </summary>
UNPARSABLE = 902,
/// <summary>
/// MUST NOT send. Used to identify malformed messages
/// </summary>
INVALID_CONTROL = 9999