README

Microsoft Azure Event Hubs Client for Golang

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Azure Event Hubs is a highly scalable publish-subscribe service that can ingest millions of events per second and stream them into multiple applications. This lets you process and analyze the massive amounts of data produced by your connected devices and applications. Once Event Hubs has collected the data, you can retrieve, transform and store it by using any real-time analytics provider or with batching/storage adapters.

Refer to the online documentation to learn more about Event Hubs in general.

This library is a pure Golang implementation of Azure Event Hubs over AMQP.

Installing the library

Use go get to acquire and install from source. Versions of the project after 1.0.1 use Go modules exclusively, which means you'll need Go 1.11 or later to ensure all of the dependencies are properly versioned.

For more information on modules, see the Go modules wiki.

go get -u github.com/Azure/azure-event-hubs-go/...

Using Event Hubs

In this section we'll cover some basics of the library to help you get started.

This library has two main dependencies, vcabbage/amqp and Azure AMQP Common. The former provides the AMQP protocol implementation and the latter provides some common authentication, persistence and request-response message flows.

Quick start

Let's send and receive "hello, world!".

package main

import (
	"context"
	"fmt"
	"os"
	"os/signal"
	"time"
	
	"github.com/Azure/azure-event-hubs-go"
)

func main() {
	connStr := "Endpoint=sb://namespace.servicebus.windows.net/;SharedAccessKeyName=RootManageSharedAccessKey;SharedAccessKey=superSecret1234=;EntityPath=hubName"
	hub, err := eventhub.NewHubFromConnectionString(connStr)

	if err != nil {
		// handle err
	}

	ctx, cancel := context.WithTimeout(context.Background(), 20*time.Second)
	defer cancel()

	// send a single message into a random partition
	err = hub.Send(ctx, eventhub.NewEventFromString("hello, world!"))
	if err != nil {
		// handle error
	}

	handler := func(c context.Context, event *eventhub.Event) error {
		fmt.Println(string(event.Data))
		return nil
	}

	// listen to each partition of the Event Hub
	runtimeInfo, err := hub.GetRuntimeInformation(ctx)
	if err != nil {
		// handle err
	}
	
	for _, partitionID := range runtimeInfo.PartitionIDs { 
		// Start receiving messages 
		// 
		// Receive blocks while attempting to connect to hub, then runs until listenerHandle.Close() is called 
		// <- listenerHandle.Done() signals listener has died 
		// listenerHandle.Err() provides the last error the receiver encountered 
		listenerHandle, err := hub.Receive(ctx, partitionID, handler, eventhub.ReceiveWithLatestOffset())
		if err != nil {
			// handle err
		}
    }

	// Wait for a signal to quit:
	signalChan := make(chan os.Signal, 1)
	signal.Notify(signalChan, os.Interrupt, os.Kill)
	<-signalChan

	hub.Close(context.Background())
}
Environment Variables

In the above example, the Hub instance was created using environment variables. Here is a list of environment variables used in this project.

Event Hub env vars
  • EVENTHUB_NAMESPACE the namespace of the Event Hub instance
  • EVENTHUB_NAME the name of the Event Hub instance
SAS TokenProvider environment variables:

There are two sets of environment variables which can produce a SAS TokenProvider

  1. Expected Environment Variables:

    • EVENTHUB_KEY_NAME the name of the Event Hub key
    • EVENTHUB_KEY_VALUE the secret for the Event Hub key named in EVENTHUB_KEY_NAME
  2. Expected Environment Variable:

    • EVENTHUB_CONNECTION_STRING connection string from the Azure portal like: Endpoint=sb://foo.servicebus.windows.net/;SharedAccessKeyName=RootManageSharedAccessKey;SharedAccessKey=fluffypuppy;EntityPath=hubName
AAD TokenProvider environment variables:
  1. Client Credentials: attempt to authenticate with a Service Principal via
    • AZURE_TENANT_ID the Azure Tenant ID
    • AZURE_CLIENT_ID the Azure Application ID
    • AZURE_CLIENT_SECRET a key / secret for the corresponding application
  2. Client Certificate: attempt to authenticate with a Service Principal via
    • AZURE_TENANT_ID the Azure Tenant ID
    • AZURE_CLIENT_ID the Azure Application ID
    • AZURE_CERTIFICATE_PATH the path to the certificate file
    • AZURE_CERTIFICATE_PASSWORD the password for the certificate

The Azure Environment used can be specified using the name of the Azure Environment set in "AZURE_ENVIRONMENT" var.

Authentication

Event Hubs offers a couple different paths for authentication, shared access signatures (SAS) and Azure Active Directory (AAD) JWT authentication. Both token types are available for use and are exposed through the TokenProvider interface.

// TokenProvider abstracts the fetching of authentication tokens
TokenProvider interface {
    GetToken(uri string) (*Token, error)
}
SAS token provider

The SAS token provider uses the namespace of the Event Hub, the name of the "Shared access policy" key and the value of the key to produce a token.

You can create new Shared access policies through the Azure portal as shown below. SAS policies in the Azure portal

You can create a SAS token provider in a couple different ways. You can build one with a key name and key value like this.

provider := sas.TokenProviderWithKey("myKeyName", "myKeyValue")

Or, you can create a token provider from environment variables like this.

// TokenProviderWithEnvironmentVars creates a new SAS TokenProvider from environment variables
//
// There are two sets of environment variables which can produce a SAS TokenProvider
//
// 1) Expected Environment Variables:
//   - "EVENTHUB_KEY_NAME" the name of the Event Hub key
//   - "EVENTHUB_KEY_VALUE" the secret for the Event Hub key named in "EVENTHUB_KEY_NAME"
//
// 2) Expected Environment Variable:
//   - "EVENTHUB_CONNECTION_STRING" connection string from the Azure portal

provider, err := sas.NewTokenProvider(sas.TokenProviderWithEnvironmentVars())
AAD JWT token provider

The AAD JWT token provider uses Azure Active Directory to authenticate the service and acquire a token (JWT) which is used to authenticate with Event Hubs. The authenticated identity must have Contributor role based authorization for the Event Hub instance. This article provides more information about this preview feature.

The easiest way to create a JWT token provider is via environment variables.

// 1. Client Credentials: attempt to authenticate with a Service Principal via "AZURE_TENANT_ID", "AZURE_CLIENT_ID" and
//    "AZURE_CLIENT_SECRET"
//
// 2. Client Certificate: attempt to authenticate with a Service Principal via "AZURE_TENANT_ID", "AZURE_CLIENT_ID",
//    "AZURE_CERTIFICATE_PATH" and "AZURE_CERTIFICATE_PASSWORD"
//
// 3. Managed Service Identity (MSI): attempt to authenticate via MSI
//
//
// The Azure Environment used can be specified using the name of the Azure Environment set in "AZURE_ENVIRONMENT" var.
provider, err := aad.NewJWTProvider(aad.JWTProviderWithEnvironmentVars())

You can also provide your own adal.ServicePrincipalToken.

config := &aad.TokenProviderConfiguration{
    ResourceURI: azure.PublicCloud.ResourceManagerEndpoint,
    Env:         &azure.PublicCloud,
}

spToken, err := config.NewServicePrincipalToken()
if err != nil {
    // handle err
}
provider, err := aad.NewJWTProvider(aad.JWTProviderWithAADToken(aadToken))
Send And Receive

The basics of messaging are sending and receiving messages. Here are the different ways you can do that.

Sending to a particular partition

By default, a Hub will send messages any of the load balanced partitions. Sometimes you want to send to only a particular partition. You can do this in two ways.

  1. You can supply a partition key on an event
    event := eventhub.NewEventFromString("foo")
    event.PartitionKey = "bazz"
    hub.Send(ctx, event) // send event to the partition ID to which partition key hashes
    
  2. You can build a hub instance that will only send to one partition.
    partitionID := "0"
    hub, err := eventhub.NewHubFromEnvironment(eventhub.HubWithPartitionedSender(partitionID))
    
Sending batches of events

Sending a batch of messages is more efficient than sending a single message.

batch := &EventBatch{
            Events: []*eventhub.Event { 
                eventhub.NewEventFromString("one"),
                eventhub.NewEventFromString("two"),
            },
        }
err := client.SendBatch(ctx, batch)
Receiving

When receiving messages from an Event Hub, you always need to specify the partition you'd like to receive from. Hub.Receive is a non-blocking call, which takes a message handler func and options. Since Event Hub is just a long log of messages, you also have to tell it where to start from. By default, a receiver will start from the beginning of the log, but there are options to help you specify your starting offset.

The Receive func returns a handle to the running receiver and an error. If error is returned, the receiver was unable to start. If error is nil, the receiver is running and can be stopped by calling Close on the Hub or the handle returned.

  • Receive messages from a partition from the beginning of the log
    handle, err := hub.Receive(ctx, partitionID, func(ctx context.Context, event *eventhub.Event) error {
        // do stuff
    })
    
  • Receive from the latest message onward
    handle, err := hub.Receive(ctx, partitionID, handler, eventhub.ReceiveWithLatestOffset())
    
  • Receive from a specified offset
    handle, err := hub.Receive(ctx, partitionID, handler, eventhub.ReceiveWithStartingOffset(offset))
    

At some point, a receiver process is going to stop. You will likely want it to start back up at the spot that it stopped processing messages. This is where message offsets can be used to start from where you have left off.

The Hub struct can be customized to use an persist.CheckpointPersister. By default, a Hub uses an in-memory CheckpointPersister, but accepts anything that implements the perist.CheckpointPersister interface.

// CheckpointPersister provides persistence for the received offset for a given namespace, hub name, consumer group, partition Id and
// offset so that if a receiver where to be interrupted, it could resume after the last consumed event.
CheckpointPersister interface {
    Write(namespace, name, consumerGroup, partitionID string, checkpoint Checkpoint) error
    Read(namespace, name, consumerGroup, partitionID string) (Checkpoint, error)
}

For example, you could use the persist.FilePersister to save your checkpoints to a directory.

persister, err := persist.NewFilePersister(directoryPath)
if err != nil {
	// handle err
}
hub, err := eventhub.NewHubFromEnvironment(eventhub.HubWithOffsetPersistence(persister))

Event Processor Host

The key to scale for Event Hubs is the idea of partitioned consumers. In contrast to the competing consumers pattern, the partitioned consumer pattern enables high scale by removing the contention bottleneck and facilitating end to end parallelism.

The Event Processor Host (EPH) is an intelligent consumer agent that simplifies the management of checkpointing, leasing, and parallel event readers. EPH is intended to be run across multiple processes and machines while load balancing message consumers. A message consumer in EPH will take a lease on a partition, begin processing messages and periodically write a check point to a persistent store. If at any time a new EPH process is added or lost, the remaining processors will balance the existing leases amongst the set of EPH processes.

The default implementation of partition leasing and check pointing is based on Azure Storage. Below is an example using EPH to start listening to all of the partitions of an Event Hub and print the messages received.

Receiving Events
package main

import (
	"context"
	"fmt"
	"os"
	"os/signal"
	"time"
	
	"github.com/Azure/go-autorest/autorest/azure"
	"github.com/Azure/azure-amqp-common-go/conn"
	"github.com/Azure/azure-amqp-common-go/sas"
	"github.com/Azure/azure-event-hubs-go/eph"
	"github.com/Azure/azure-event-hubs-go"
	"github.com/Azure/azure-event-hubs-go/storage"
	"github.com/Azure/azure-storage-blob-go/2016-05-31/azblob"
)

func main() {
	// Azure Storage account information
    storageAccountName := "mystorageaccount"
    storageAccountKey := "Zm9vCg=="
    // Azure Storage container to store leases and checkpoints
    storageContainerName := "ephcontainer"
    
    // Azure Event Hub connection string
    eventHubConnStr := "Endpoint=sb://namespace.servicebus.windows.net/;SharedAccessKeyName=RootManageSharedAccessKey;SharedAccessKey=superSecret1234=;EntityPath=hubName"
    parsed, err := conn.ParsedConnectionFromStr(eventHubConnStr)
    if err != nil {
        // handle error
    }
    
    // create a new Azure Storage Leaser / Checkpointer
    cred := azblob.NewSharedKeyCredential(storageAccountName, storageAccountKey)
    leaserCheckpointer, err := storage.NewStorageLeaserCheckpointer(cred, storageAccountName, storageContainerName, azure.PublicCloud)
    if err != nil {
    	// handle error
    }
    
    // SAS token provider for Azure Event Hubs
    provider, err := sas.NewTokenProvider(sas.TokenProviderWithKey(parsed.KeyName, parsed.Key))
    if err != nil {
    	// handle error
    }
    
    ctx, cancel := context.WithTimeout(context.Background(), 20*time.Second)
    defer cancel()
    // create a new EPH processor
    processor, err := eph.New(ctx, parsed.Namespace, parsed.HubName, provider, leaserCheckpointer, leaserCheckpointer)
    if err != nil {
        // handle error
    }
    
    // register a message handler -- many can be registered
    handlerID, err := processor.RegisterHandler(ctx, 
    	func(c context.Context, event *eventhub.Event) error {
    		fmt.Println(string(event.Data))
    		return nil
    })
    if err != nil {
        // handle error
    }
    
    // unregister a handler to stop that handler from receiving events
    // processor.UnregisterHandler(ctx, handleID)
    
    // start handling messages from all of the partitions balancing across multiple consumers
    processor.StartNonBlocking(ctx)
    
    // Wait for a signal to quit:
    signalChan := make(chan os.Signal, 1)
    signal.Notify(signalChan, os.Interrupt, os.Kill)
    <-signalChan
    
    err = processor.Close(context.Background())
    if err != nil {
    	// handle error
    }
}

Examples

Contributing

This project welcomes contributions and suggestions. Most contributions require you to agree to a Contributor License Agreement (CLA) declaring that you have the right to, and actually do, grant us the rights to use your contribution. For details, visit https://cla.microsoft.com.

When you submit a pull request, a CLA-bot will automatically determine whether you need to provide a CLA and decorate the PR appropriately (e.g., label, comment). Simply follow the instructions provided by the bot. You will only need to do this once across all repos using our CLA.

This project has adopted the Microsoft Open Source Code of Conduct. For more information see the Code of Conduct FAQ or contact opencode@microsoft.com with any additional questions or comments.

See contributing.md.

License

MIT, see LICENSE.

Expand ▾ Collapse ▴

Documentation

Overview

    Package eventhub provides functionality for interacting with Azure Event Hubs.

    Index

    Examples

    Constants

    View Source
    const (
    	// DefaultConsumerGroup is the default name for a event stream consumer group
    	DefaultConsumerGroup = "$Default"
    )
    View Source
    const (
    	// MsftVendor is the Microsoft vendor identifier
    	MsftVendor = "com.microsoft"
    )
    View Source
    const (
    	// Version is the semantic version number
    	Version = "1.3.1"
    )

    Variables

    This section is empty.

    Functions

    func ApplyComponentInfo

    func ApplyComponentInfo(span *trace.Span)

      ApplyComponentInfo applies eventhub library and network info to the span

      Types

      type BaseEntityDescription

      type BaseEntityDescription struct {
      	InstanceMetadataSchema *string `xml:"xmlns:i,attr,omitempty"`
      	ServiceBusSchema       *string `xml:"xmlns,attr,omitempty"`
      }

        BaseEntityDescription provides common fields which are part of Queues, Topics and Subscriptions

        type Event

        type Event struct {
        	Data         []byte
        	PartitionKey *string
        	Properties   map[string]interface{}
        	ID           string
        
        	SystemProperties *SystemProperties
        	// contains filtered or unexported fields
        }

          Event is an Event Hubs message to be sent or received

          func NewEvent

          func NewEvent(data []byte) *Event

            NewEvent builds an Event from a slice of data

            func NewEventFromString

            func NewEventFromString(message string) *Event

              NewEventFromString builds an Event from a string message

              func (*Event) Get

              func (e *Event) Get(key string) (interface{}, bool)

                Get will fetch a property from the event

                func (*Event) GetCheckpoint

                func (e *Event) GetCheckpoint() persist.Checkpoint

                  GetCheckpoint returns the checkpoint information on the Event

                  func (*Event) Set

                  func (e *Event) Set(key string, value interface{})

                    Set will set a key in the event properties

                    type EventBatch

                    type EventBatch struct {
                    	Events       []*Event
                    	PartitionKey *string
                    	Properties   map[string]interface{}
                    	ID           string
                    }

                      EventBatch is a batch of Event Hubs messages to be sent

                      func NewEventBatch

                      func NewEventBatch(events []*Event) *EventBatch

                        NewEventBatch builds an EventBatch from an array of Events

                        type Handler

                        type Handler func(ctx context.Context, event *Event) error

                          Handler is the function signature for any receiver of events

                          type Hub

                          type Hub struct {
                          	// contains filtered or unexported fields
                          }

                            Hub provides the ability to send and receive Event Hub messages

                            Example (HelloWorld)
                            Output:
                            
                            Hello World!
                            
                            Example (WebSocket)
                            Output:
                            
                            this message was sent and received via web socket!!
                            

                            func NewHub

                            func NewHub(namespace, name string, tokenProvider auth.TokenProvider, opts ...HubOption) (*Hub, error)

                              NewHub creates a new Event Hub client for sending and receiving messages

                              func NewHubFromConnectionString

                              func NewHubFromConnectionString(connStr string, opts ...HubOption) (*Hub, error)

                                NewHubFromConnectionString creates a new Event Hub client for sending and receiving messages from a connection string formatted like the following:

                                Endpoint=sb://namespace.servicebus.windows.net/;SharedAccessKeyName=RootManageSharedAccessKey;SharedAccessKey=superSecret1234=;EntityPath=hubName
                                

                                func NewHubFromEnvironment

                                func NewHubFromEnvironment(opts ...HubOption) (*Hub, error)

                                  NewHubFromEnvironment creates a new Event Hub client for sending and receiving messages from environment variables

                                  Expected Environment Variables:

                                  - "EVENTHUB_NAMESPACE" the namespace of the Event Hub instance
                                  - "EVENTHUB_NAME" the name of the Event Hub instance
                                  

                                  This method depends on NewHubWithNamespaceNameAndEnvironment which will attempt to build a token provider from environment variables. If unable to build a AAD Token Provider it will fall back to a SAS token provider. If neither can be built, it will return error.

                                  SAS TokenProvider environment variables:

                                  There are two sets of environment variables which can produce a SAS TokenProvider

                                  1) Expected Environment Variables:
                                    - "EVENTHUB_NAMESPACE" the namespace of the Event Hub instance
                                    - "EVENTHUB_KEY_NAME" the name of the Event Hub key
                                    - "EVENTHUB_KEY_VALUE" the secret for the Event Hub key named in "EVENTHUB_KEY_NAME"
                                  
                                  2) Expected Environment Variable:
                                    - "EVENTHUB_CONNECTION_STRING" connection string from the Azure portal
                                  

                                  AAD TokenProvider environment variables:

                                  1. client Credentials: attempt to authenticate with a Service Principal via "AZURE_TENANT_ID", "AZURE_CLIENT_ID" and
                                    "AZURE_CLIENT_SECRET"
                                  
                                  2. client Certificate: attempt to authenticate with a Service Principal via "AZURE_TENANT_ID", "AZURE_CLIENT_ID",
                                    "AZURE_CERTIFICATE_PATH" and "AZURE_CERTIFICATE_PASSWORD"
                                  
                                  3. Managed Service Identity (MSI): attempt to authenticate via MSI
                                  

                                  The Azure Environment used can be specified using the name of the Azure Environment set in the AZURE_ENVIRONMENT var.

                                  func NewHubWithNamespaceNameAndEnvironment

                                  func NewHubWithNamespaceNameAndEnvironment(namespace, name string, opts ...HubOption) (*Hub, error)

                                    NewHubWithNamespaceNameAndEnvironment creates a new Event Hub client for sending and receiving messages from environment variables with supplied namespace and name which will attempt to build a token provider from environment variables. If unable to build a AAD Token Provider it will fall back to a SAS token provider. If neither can be built, it will return error.

                                    SAS TokenProvider environment variables:

                                    There are two sets of environment variables which can produce a SAS TokenProvider

                                    1) Expected Environment Variables:
                                      - "EVENTHUB_KEY_NAME" the name of the Event Hub key
                                      - "EVENTHUB_KEY_VALUE" the secret for the Event Hub key named in "EVENTHUB_KEY_NAME"
                                    
                                    2) Expected Environment Variable:
                                      - "EVENTHUB_CONNECTION_STRING" connection string from the Azure portal
                                    

                                    AAD TokenProvider environment variables:

                                    1. client Credentials: attempt to authenticate with a Service Principal via "AZURE_TENANT_ID", "AZURE_CLIENT_ID" and
                                      "AZURE_CLIENT_SECRET"
                                    
                                    2. client Certificate: attempt to authenticate with a Service Principal via "AZURE_TENANT_ID", "AZURE_CLIENT_ID",
                                      "AZURE_CERTIFICATE_PATH" and "AZURE_CERTIFICATE_PASSWORD"
                                    
                                    3. Managed Service Identity (MSI): attempt to authenticate via MSI on the default local MSI internally addressable IP
                                      and port. See: adal.GetMSIVMEndpoint()
                                    

                                    The Azure Environment used can be specified using the name of the Azure Environment set in the AZURE_ENVIRONMENT var.

                                    func (*Hub) Close

                                    func (h *Hub) Close(ctx context.Context) error

                                      Close drains and closes all of the existing senders, receivers and connections

                                      func (*Hub) GetPartitionInformation

                                      func (h *Hub) GetPartitionInformation(ctx context.Context, partitionID string) (*HubPartitionRuntimeInformation, error)

                                        GetPartitionInformation fetches runtime information about a specific partition from the Event Hub management node

                                        func (*Hub) GetRuntimeInformation

                                        func (h *Hub) GetRuntimeInformation(ctx context.Context) (*HubRuntimeInformation, error)

                                          GetRuntimeInformation fetches runtime information from the Event Hub management node

                                          func (*Hub) Receive

                                          func (h *Hub) Receive(ctx context.Context, partitionID string, handler Handler, opts ...ReceiveOption) (*ListenerHandle, error)

                                            Receive subscribes for messages sent to the provided entityPath.

                                            The context passed into Receive is only used to limit the amount of time the caller will wait for the Receive method to connect to the Event Hub. The context passed in does not control the lifetime of Receive after connection.

                                            If Receive encounters an initial error setting up the connection, an error will be returned.

                                            If Receive starts successfully, a *ListenerHandle and a nil error will be returned. The ListenerHandle exposes methods which will help manage the life span of the receiver.

                                            ListenerHandle.Close(ctx) closes the receiver

                                            ListenerHandle.Done() signals the consumer when the receiver has stopped

                                            ListenerHandle.Err() provides the last error the listener encountered and was unable to recover from

                                            func (*Hub) Send

                                            func (h *Hub) Send(ctx context.Context, event *Event, opts ...SendOption) error

                                              Send sends an event to the Event Hub

                                              Send will retry sending the message for as long as the context allows

                                              func (*Hub) SendBatch

                                              func (h *Hub) SendBatch(ctx context.Context, batch *EventBatch, opts ...SendOption) error

                                                SendBatch sends an EventBatch to the Event Hub

                                                SendBatch will retry sending the message for as long as the context allows

                                                type HubDescription

                                                type HubDescription struct {
                                                	XMLName                  xml.Name               `xml:"EventHubDescription"`
                                                	MessageRetentionInDays   *int32                 `xml:"MessageRetentionInDays,omitempty"`
                                                	SizeInBytes              *int64                 `xml:"SizeInBytes,omitempty"`
                                                	Status                   *eventhub.EntityStatus `xml:"Status,omitempty"`
                                                	CreatedAt                *date.Time             `xml:"CreatedAt,omitempty"`
                                                	UpdatedAt                *date.Time             `xml:"UpdatedAt,omitempty"`
                                                	PartitionCount           *int32                 `xml:"PartitionCount,omitempty"`
                                                	PartitionIDs             *[]string              `xml:"PartitionIds>string,omitempty"`
                                                	EntityAvailabilityStatus *string                `xml:"EntityAvailabilityStatus,omitempty"`
                                                	BaseEntityDescription
                                                }

                                                  HubDescription is the content type for Event Hub management requests

                                                  type HubEntity

                                                  type HubEntity struct {
                                                  	*HubDescription
                                                  	Name string
                                                  }

                                                    HubEntity is the Azure Event Hub description of a Hub for management activities

                                                    type HubManagementOption

                                                    type HubManagementOption func(description *HubDescription) error

                                                      HubManagementOption provides structure for configuring new Event Hubs

                                                      func HubWithMessageRetentionInDays

                                                      func HubWithMessageRetentionInDays(days int32) HubManagementOption

                                                        HubWithMessageRetentionInDays configures an Event Hub to retain messages for that number of days

                                                        func HubWithPartitionCount

                                                        func HubWithPartitionCount(count int32) HubManagementOption

                                                          HubWithPartitionCount configures an Event Hub to have the specified number of partitions. More partitions == more throughput

                                                          type HubManager

                                                          type HubManager struct {
                                                          	// contains filtered or unexported fields
                                                          }

                                                            HubManager provides CRUD functionality for Event Hubs

                                                            func NewHubManagerFromAzureEnvironment

                                                            func NewHubManagerFromAzureEnvironment(namespace string, tokenProvider auth.TokenProvider, env azure.Environment) (*HubManager, error)

                                                              NewHubManagerFromAzureEnvironment builds a HubManager from a Event Hub name, SAS or AAD token provider and Azure Environment

                                                              func NewHubManagerFromConnectionString

                                                              func NewHubManagerFromConnectionString(connStr string) (*HubManager, error)

                                                                NewHubManagerFromConnectionString builds a HubManager from an Event Hub connection string

                                                                func (*HubManager) Delete

                                                                func (hm *HubManager) Delete(ctx context.Context, name string) error

                                                                  Delete deletes an Event Hub entity by name

                                                                  func (HubManager) Execute

                                                                  func (em HubManager) Execute(ctx context.Context, method string, entityPath string, body io.Reader) (*http.Response, error)

                                                                    Execute performs an HTTP request given a http method, path and body

                                                                    func (*HubManager) Get

                                                                    func (hm *HubManager) Get(ctx context.Context, name string) (*HubEntity, error)

                                                                      Get fetches an Event Hubs Hub entity by name

                                                                      func (*HubManager) List

                                                                      func (hm *HubManager) List(ctx context.Context) ([]*HubEntity, error)

                                                                        List fetches all of the Hub for an Event Hubs Namespace

                                                                        func (HubManager) Post

                                                                        func (em HubManager) Post(ctx context.Context, entityPath string, body []byte) (*http.Response, error)

                                                                          Post performs an HTTP POST for a given entity path and body

                                                                          func (*HubManager) Put

                                                                          func (hm *HubManager) Put(ctx context.Context, name string, opts ...HubManagementOption) (*HubEntity, error)

                                                                            Put creates or updates an Event Hubs Hub

                                                                            type HubOption

                                                                            type HubOption func(h *Hub) error

                                                                              HubOption provides structure for configuring new Event Hub clients. For building new Event Hubs, see HubManagementOption.

                                                                              func HubWithEnvironment

                                                                              func HubWithEnvironment(env azure.Environment) HubOption

                                                                                HubWithEnvironment configures the Hub to use the specified environment.

                                                                                By default, the Hub instance will use Azure US Public cloud environment

                                                                                func HubWithOffsetPersistence

                                                                                func HubWithOffsetPersistence(offsetPersister persist.CheckpointPersister) HubOption

                                                                                  HubWithOffsetPersistence configures the Hub instance to read and write offsets so that if a Hub is interrupted, it can resume after the last consumed event.

                                                                                  func HubWithPartitionedSender

                                                                                  func HubWithPartitionedSender(partitionID string) HubOption

                                                                                    HubWithPartitionedSender configures the Hub instance to send to a specific event Hub partition

                                                                                    func HubWithUserAgent

                                                                                    func HubWithUserAgent(userAgent string) HubOption

                                                                                      HubWithUserAgent configures the Hub to append the given string to the user agent sent to the server

                                                                                      This option can be specified multiple times to add additional segments.

                                                                                      Max user agent length is specified by the const maxUserAgentLen.

                                                                                      func HubWithWebSocketConnection

                                                                                      func HubWithWebSocketConnection() HubOption

                                                                                        HubWithWebSocketConnection configures the Hub to use a WebSocket connection wss:// rather than amqps://

                                                                                        type HubPartitionRuntimeInformation

                                                                                        type HubPartitionRuntimeInformation struct {
                                                                                        	HubPath                 string    `mapstructure:"name"`
                                                                                        	PartitionID             string    `mapstructure:"partition"`
                                                                                        	BeginningSequenceNumber int64     `mapstructure:"begin_sequence_number"`
                                                                                        	LastSequenceNumber      int64     `mapstructure:"last_enqueued_sequence_number"`
                                                                                        	LastEnqueuedOffset      string    `mapstructure:"last_enqueued_offset"`
                                                                                        	LastEnqueuedTimeUtc     time.Time `mapstructure:"last_enqueued_time_utc"`
                                                                                        }

                                                                                          HubPartitionRuntimeInformation provides management node information about a given Event Hub partition

                                                                                          type HubRuntimeInformation

                                                                                          type HubRuntimeInformation struct {
                                                                                          	Path           string    `mapstructure:"name"`
                                                                                          	CreatedAt      time.Time `mapstructure:"created_at"`
                                                                                          	PartitionCount int       `mapstructure:"partition_count"`
                                                                                          	PartitionIDs   []string  `mapstructure:"partition_ids"`
                                                                                          }

                                                                                            HubRuntimeInformation provides management node information about a given Event Hub instance

                                                                                            type ListenerHandle

                                                                                            type ListenerHandle struct {
                                                                                            	// contains filtered or unexported fields
                                                                                            }

                                                                                              ListenerHandle provides the ability to close or listen to the close of a Receiver

                                                                                              func (*ListenerHandle) Close

                                                                                              func (lc *ListenerHandle) Close(ctx context.Context) error

                                                                                                Close will close the listener

                                                                                                func (*ListenerHandle) Done

                                                                                                func (lc *ListenerHandle) Done() <-chan struct{}

                                                                                                  Done will close the channel when the listener has stopped

                                                                                                  func (*ListenerHandle) Err

                                                                                                  func (lc *ListenerHandle) Err() error

                                                                                                    Err will return the last error encountered

                                                                                                    type Manager

                                                                                                    type Manager interface {
                                                                                                    	GetRuntimeInformation(context.Context) (HubRuntimeInformation, error)
                                                                                                    	GetPartitionInformation(context.Context, string) (HubPartitionRuntimeInformation, error)
                                                                                                    }

                                                                                                      Manager provides the ability to query management node information about a node

                                                                                                      type PartitionedReceiver

                                                                                                      type PartitionedReceiver interface {
                                                                                                      	Receive(ctx context.Context, partitionID string, handler Handler, opts ...ReceiveOption) (ListenerHandle, error)
                                                                                                      }

                                                                                                        PartitionedReceiver provides the ability to receive messages from a given partition

                                                                                                        type ReceiveOption

                                                                                                        type ReceiveOption func(receiver *receiver) error

                                                                                                          ReceiveOption provides a structure for configuring receivers

                                                                                                          func ReceiveFromTimestamp

                                                                                                          func ReceiveFromTimestamp(t time.Time) ReceiveOption

                                                                                                            ReceiveFromTimestamp configures the receiver to start receiving from a specific point in time in the event stream

                                                                                                            func ReceiveWithConsumerGroup

                                                                                                            func ReceiveWithConsumerGroup(consumerGroup string) ReceiveOption

                                                                                                              ReceiveWithConsumerGroup configures the receiver to listen to a specific consumer group

                                                                                                              func ReceiveWithEpoch

                                                                                                              func ReceiveWithEpoch(epoch int64) ReceiveOption

                                                                                                                ReceiveWithEpoch configures the receiver to use an epoch. Specifying an epoch for a receiver will cause any receiver with a lower epoch value to be disconnected from the message broker. If a receiver attempts to start with a lower epoch than the broker currently knows for a given partition, the broker will respond with an error on initiation of the receive request.

                                                                                                                Ownership enforcement: Once you created an epoch based receiver, you cannot create a non-epoch receiver to the same consumer group / partition combo until all receivers to the combo are closed.

                                                                                                                Ownership stealing: If a receiver with higher epoch value is created for a consumer group / partition combo, any older epoch receiver to that combo will be force closed.

                                                                                                                func ReceiveWithLatestOffset

                                                                                                                func ReceiveWithLatestOffset() ReceiveOption

                                                                                                                  ReceiveWithLatestOffset configures the receiver to start at a given position in the event stream

                                                                                                                  func ReceiveWithPrefetchCount

                                                                                                                  func ReceiveWithPrefetchCount(prefetch uint32) ReceiveOption

                                                                                                                    ReceiveWithPrefetchCount configures the receiver to attempt to fetch as many messages as the prefetch amount

                                                                                                                    func ReceiveWithStartingOffset

                                                                                                                    func ReceiveWithStartingOffset(offset string) ReceiveOption

                                                                                                                      ReceiveWithStartingOffset configures the receiver to start at a given position in the event stream

                                                                                                                      type SendOption

                                                                                                                      type SendOption func(event *Event) error

                                                                                                                        SendOption provides a way to customize a message on sending

                                                                                                                        func SendWithMessageID

                                                                                                                        func SendWithMessageID(messageID string) SendOption

                                                                                                                          SendWithMessageID configures the message with a message ID

                                                                                                                          type Sender

                                                                                                                          type Sender interface {
                                                                                                                          	Send(ctx context.Context, event *Event, opts ...SendOption) error
                                                                                                                          	SendBatch(ctx context.Context, batch *EventBatch, opts ...SendOption) error
                                                                                                                          }

                                                                                                                            Sender provides the ability to send a messages

                                                                                                                            type SystemProperties

                                                                                                                            type SystemProperties struct {
                                                                                                                            	SequenceNumber *int64     `mapstructure:"x-opt-sequence-number"` // unique sequence number of the message
                                                                                                                            	EnqueuedTime   *time.Time `mapstructure:"x-opt-enqueued-time"`   // time the message landed in the message queue
                                                                                                                            	Offset         *int64     `mapstructure:"x-opt-offset"`
                                                                                                                            	PartitionID    *int16     `mapstructure:"x-opt-partition-id"`
                                                                                                                            	PartitionKey   *string    `mapstructure:"x-opt-partition-key"`
                                                                                                                            }

                                                                                                                              SystemProperties are used to store properties that are set by the system.

                                                                                                                              Directories

                                                                                                                              Path Synopsis
                                                                                                                              _examples
                                                                                                                              Package atom contains base data structures for use in the Azure Event Hubs management HTTP API
                                                                                                                              Package atom contains base data structures for use in the Azure Event Hubs management HTTP API
                                                                                                                              Package eph provides functionality for balancing load of Event Hub receivers through scheduling receivers across processes and machines.
                                                                                                                              Package eph provides functionality for balancing load of Event Hub receivers through scheduling receivers across processes and machines.
                                                                                                                              internal
                                                                                                                              test
                                                                                                                              Package test is an internal package to handle common test setup
                                                                                                                              Package test is an internal package to handle common test setup
                                                                                                                              Package storage provides implementations for Checkpointer and Leaser from package eph for persisting leases and checkpoints for the Event Processor Host using Azure Storage as a durable store.
                                                                                                                              Package storage provides implementations for Checkpointer and Leaser from package eph for persisting leases and checkpoints for the Event Processor Host using Azure Storage as a durable store.