README
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DDP in Go
Meteor DDP library for Go. This library allows Go applications to connect to Meteor applications, subscribe to Meteor publications, read from a cached Collection (similar to minimongo), and call Meteor methods on the server.
See ddp/_examples for some tips and an example app that walks through all the features of the library.
Documentation
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Overview ¶
Package ddp implements the MeteorJS DDP protocol over websockets. Fallback to long polling is NOT supported (and is not planned on ever being supported by this library). We will try to model the library after `net/http` - right now the library is bare bones and doesn't provide the plug-ability of http. However, that's the goal for the package eventually.
Index ¶
- Constants
- func IgnoreErr(err error, msg string, l *log.Entry)
- type Call
- type Client
- func (c *Client) AddConnectionListener(listener ConnectionListener)
- func (c *Client) AddStatusListener(listener StatusListener)
- func (c *Client) Call(serviceMethod string, args ...interface{}) (interface{}, error)
- func (c *Client) Close()
- func (c *Client) CollectionByName(name string) Collection
- func (c *Client) CollectionStats() []CollectionStats
- func (c *Client) Connect() error
- func (c *Client) Go(serviceMethod string, done chan *Call, args ...interface{}) *Call
- func (c *Client) Ping()
- func (c *Client) PingPong(id string, timeout time.Duration, handler func(error))
- func (c *Client) Reconnect()
- func (c *Client) ResetStats()
- func (c *Client) Send(msg interface{}) error
- func (c *Client) Session() string
- func (c *Client) Stats() *ClientStats
- func (c *Client) Sub(subName string, args ...interface{}) error
- func (c *Client) Subscribe(subName string, done chan *Call, args ...interface{}) *Call
- func (c *Client) Version() string
- type ClientStats
- type Collection
- type CollectionStats
- type Connect
- type ConnectionListener
- type ConnectionNotifier
- type KeyCache
- type KeyManager
- type Login
- type LoginResume
- type Message
- type Method
- type MockCache
- type OrderedCache
- type Password
- type Ping
- type PingTracker
- type Pong
- type ReaderStats
- type Stats
- type StatsTracker
- type StatusListener
- type StatusNotifier
- type Sub
- type Time
- type Update
- type UpdateListener
- type User
- type WriterStats
Constants ¶
const ( DISCONNECTED = iota DISCONNECTING CONNECTED DIALING CONNECTING RECONNECTING )
Variables ¶
This section is empty.
Functions ¶
Types ¶
type Call ¶
type Call struct {
ID string // The uuid for this method call
ServiceMethod string // The name of the service and method to call.
Args interface{} // The argument to the function (*struct).
Reply interface{} // The reply from the function (*struct).
Error error // After completion, the error status.
Done chan *Call // Strobes when call is complete.
Owner *Client // Client that owns the method call
// contains filtered or unexported fields
}
Call represents an active RPC call.
type Client ¶
type Client struct {
// HeartbeatInterval is the time between heartbeats to send
HeartbeatInterval time.Duration
// HeartbeatTimeout is the time for a heartbeat ping to timeout
HeartbeatTimeout time.Duration
// ReconnectInterval is the time between reconnections on bad connections
ReconnectInterval time.Duration
// KeyManager tracks IDs for ddp messages
KeyManager
// contains filtered or unexported fields
}
Client represents a DDP client connection. The DDP client establish a DDP session and acts as a message pump for other tools.
func NewClientWithLogger ¶ added in v0.0.6
NewClientWithLogger creates a default client (using an internal websocket) to the provided URL using the origin for the connection. The client will automatically connect, upgrade to a websocket, and establish a DDP connection session before returning the client. The client will automatically and internally handle heartbeats and reconnects.
TBD create an option to use an external websocket (aka htt.Transport) TBD create an option to substitute heartbeat and reconnect behavior (aka http.Transport) TBD create an option to hijack the connection (aka http.Hijacker) TBD create profiling features (aka net/http/pprof)
func (*Client) AddConnectionListener ¶
func (c *Client) AddConnectionListener(listener ConnectionListener)
AddConnectionListener in order to receive connection updates.
func (*Client) AddStatusListener ¶
func (c *Client) AddStatusListener(listener StatusListener)
AddStatusListener in order to receive status change updates.
func (*Client) Call ¶
Call invokes the named function, waits for it to complete, and returns its error status.
func (*Client) CollectionByName ¶
func (c *Client) CollectionByName(name string) Collection
CollectionByName retrieves a collection by its name.
func (*Client) CollectionStats ¶
func (c *Client) CollectionStats() []CollectionStats
CollectionStats returns a snapshot of statistics for the currently known collections.
func (*Client) Go ¶
Go invokes the function asynchronously. It returns the Call structure representing the invocation. The done channel will signal when the call is complete by returning the same Call object. If done is nil, Go will allocate a new channel. If non-nil, done must be buffered or Go will deliberately crash.
Go and Call are modeled after the standard `net/rpc` package versions.
func (*Client) Ping ¶
func (c *Client) Ping()
Ping sends a heartbeat signal to the server. The Ping doesn't look for a response but may trigger the connection to reconnect if the ping times out. This is primarily useful for reviving an unresponsive Client connection.
func (*Client) PingPong ¶
PingPong sends a heartbeat signal to the server and calls the provided function when a pong is received. An optional id can be sent to help track the responses - or an empty string can be used. It is the responsibility of the caller to respond to any errors that may occur.
func (*Client) Reconnect ¶
func (c *Client) Reconnect()
Reconnect attempts to reconnect the client to the server on the existing DDP session.
TODO needs a reconnect backoff so we don't trash a down server TODO reconnect should not allow more reconnects while a reconnection is already in progress.
func (*Client) ResetStats ¶
func (c *Client) ResetStats()
ResetStats resets the statistics for the client.
func (*Client) Send ¶
Send transmits messages to the server. The msg parameter must be json encoder compatible.
func (*Client) Stats ¶
func (c *Client) Stats() *ClientStats
Stats returns the read and write statistics of the client.
type ClientStats ¶
type ClientStats struct {
// Reads provides statistics on the raw i/o network reads for the current connection.
Reads *Stats
// Reads provides statistics on the raw i/o network reads for the all client connections.
TotalReads *Stats
// Writes provides statistics on the raw i/o network writes for the current connection.
Writes *Stats
// Writes provides statistics on the raw i/o network writes for all the client connections.
TotalWrites *Stats
// Reconnects is the number of reconnections the client has made.
Reconnects int64
// PingsSent is the number of pings sent by the client
PingsSent int64
// PingsRecv is the number of pings received by the client
PingsRecv int64
}
ClientStats displays combined statistics for the Client.
func (*ClientStats) String ¶
func (stats *ClientStats) String() string
String produces a compact string representation of the client stats.
type Collection ¶
type Collection interface {
// FindOne queries objects and returns the first match.
FindOne(id string) Update
// FindAll returns a map of all items in the cache - this is a hack
// until we have time to build out a real minimongo interface.
FindAll() map[string]Update
// AddUpdateListener adds a channel that receives update messages.
AddUpdateListener(listener UpdateListener)
// contains filtered or unexported methods
}
Collection managed cached collection data sent from the server in a livedata subscription.
It would be great to build an entire mongo compatible local store (minimongo)
func NewCollection ¶
func NewCollection(name string) Collection
NewCollection creates a new collection - always KeyCache.
func NewMockCollection ¶
func NewMockCollection() Collection
NewMockCollection creates an empty collection that does nothing.
type CollectionStats ¶
type CollectionStats struct {
Name string // Name of the collection
Count int // Count is the total number of documents in the collection
}
CollectionStats combines statistics about a collection.
func (*CollectionStats) String ¶
func (s *CollectionStats) String() string
String produces a compact string representation of the collection stat.
type Connect ¶
type Connect struct {
Message
Version string `json:"version"`
Support []string `json:"support"`
Session string `json:"session,omitempty"`
}
Connect represents a DDP connect message.
func NewReconnect ¶
NewReconnect creates a new connect message with a session ID to resume.
type ConnectionListener ¶
type ConnectionListener interface {
Connected()
}
type ConnectionNotifier ¶
type ConnectionNotifier interface {
AddConnectionListener(listener ConnectionListener)
}
type KeyCache ¶
type KeyCache struct {
// The name of the collection
Name string
// contains filtered or unexported fields
}
KeyCache caches items keyed on unique ID.
func (*KeyCache) AddUpdateListener ¶
func (c *KeyCache) AddUpdateListener(listener UpdateListener)
AddUpdateListener adds a listener for changes on a collection.
type KeyManager ¶ added in v0.0.3
type KeyManager struct {
// contains filtered or unexported fields
}
KeyManager provides simple incrementing IDs for ddp messages.
func NewKeyManager ¶ added in v0.0.3
func NewKeyManager() *KeyManager
NewKeyManager creates a new instance and sets up resources.
func (*KeyManager) Next ¶ added in v0.0.3
func (id *KeyManager) Next() string
Next issues a new ID for use in calls.
type Login ¶
Login provides a Meteor.Accounts password login support
func NewEmailLogin ¶
func NewUsernameLogin ¶
type LoginResume ¶
type LoginResume struct {
Token string `json:"resume"`
}
func NewLoginResume ¶
func NewLoginResume(token string) *LoginResume
type Method ¶
type Method struct {
Message
ServiceMethod string `json:"method"`
Args []interface{} `json:"params"`
}
Method is used to send a remote procedure call to the server.
type MockCache ¶
type MockCache struct {
}
MockCache implements the Collection interface but does nothing with the data.
func (*MockCache) AddUpdateListener ¶
func (c *MockCache) AddUpdateListener(ch UpdateListener)
AddUpdateListener does nothing.
type OrderedCache ¶
type OrderedCache struct {
// contains filtered or unexported fields
}
OrderedCache caches items based on list order. This is a placeholder, currently not implemented as the Meteor server does not transmit ordered collections over DDP yet.
func (*OrderedCache) AddUpdateListener ¶
func (c *OrderedCache) AddUpdateListener(ch UpdateListener)
AddUpdateListener does nothing.
func (*OrderedCache) FindAll ¶
func (c *OrderedCache) FindAll() map[string]Update
FindAll returns a dump of all items in the collection
func (*OrderedCache) FindOne ¶
func (c *OrderedCache) FindOne(id string) Update
FindOne returns the item with matching id.
type Password ¶
func NewPassword ¶
type PingTracker ¶ added in v0.0.3
type PingTracker struct {
// contains filtered or unexported fields
}
PingTracker tracks in-flight pings.
type ReaderStats ¶
type ReaderStats struct {
StatsTracker
Reader io.Reader
}
ReaderStats tracks statistics on any io.Reader. ReaderStats wraps a Reader and passes data to the actual data consumer.
func NewReaderStats ¶
func NewReaderStats(reader io.Reader) *ReaderStats
NewReaderStats creates a ReaderStats object for the provided Reader.
type Stats ¶
type Stats struct {
// Bytes is the total number of bytes transferred.
Bytes int64
// Ops is the total number of i/o operations performed.
Ops int64
// Errors is the total number of i/o errors encountered.
Errors int64
// Runtime is the duration that stats have been gathered.
Runtime time.Duration
}
Stats tracks statistics for i/o operations.
type StatsTracker ¶
type StatsTracker struct {
// contains filtered or unexported fields
}
StatsTracker provides the basic tooling for tracking i/o stats.
func NewStatsTracker ¶
func NewStatsTracker() *StatsTracker
NewStatsTracker create a new tracker with start time set to now.
func (*StatsTracker) Op ¶
func (t *StatsTracker) Op(n int, err error) (int, error)
Op records an i/o operation. The parameters are passed through to allow easy chaining.
func (*StatsTracker) Reset ¶
func (t *StatsTracker) Reset() *Stats
Reset all stats to initial values.
func (*StatsTracker) Snapshot ¶
func (t *StatsTracker) Snapshot() *Stats
Snapshot takes a snapshot of the current Reader statistics.
type StatusListener ¶
type StatusListener interface {
Status(status int)
}
type StatusNotifier ¶
type StatusNotifier interface {
AddStatusListener(listener StatusListener)
}
type Time ¶ added in v0.0.3
Time is an alias for time.Time with custom json marshalling implementations to support ejson.
func UnixMilli ¶ added in v0.0.3
UnixMilli creates a new Time from the given unix millis but in UTC (as opposed to time.UnixMilli which returns time in the local time zone). This supports the proper loading of times from EJSON $date objects.
func (Time) MarshalJSON ¶ added in v0.0.3
func (*Time) UnmarshalJSON ¶ added in v0.0.3
type UpdateListener ¶
type WriterStats ¶
type WriterStats struct {
StatsTracker
Writer io.Writer
}
WriterStats tracks statistics on any io.Writer. WriterStats wraps a Writer and passes data to the actual data producer.
func NewWriterStats ¶
func NewWriterStats(writer io.Writer) *WriterStats
NewWriterStats creates a WriterStats object for the provided Writer.
Source Files
Directories