[receiver/azureeventhub] Set Consumer Group by Configuration (#28634)

**Description:** <Describe what has changed.>
<!--Ex. Fixing a bug - Describe the bug and how this fixes the issue.
Ex. Adding a feature - Explain what this achieves.-->
Allow the Consumer Group to be set in the Configuration.

**Link to tracking Issue:** <Issue number if applicable>
[#28633]

**Testing:** <Describe what testing was performed and which tests were
added.>
Locally tested and verified. No unit testing added.

**Documentation:** <Describe the documentation added.>
New configuration option added to README.

.chloggen/eventhubreceiver-allow-consumer-group-in-configuration.yaml

@@ -0,0 +1,27 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: enhancement
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: azureevenhubreceiver
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Allow the Consumer Group to be set in the Configuration.
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [28633]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:
+
+# If your change doesn't affect end users or the exported elements of any package,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: []

receiver/azureeventhubreceiver/README.md

@@ -26,6 +26,9 @@ Event Hub, transforms them, and pushes them through the collector pipeline.
 ### connection (Required)
 A string describing the connection to an Azure event hub.
 
+### group (Optional)
+The Consumer Group to read from. If empty will default to the default Consumer Group $Default
+
 ### partition (Optional)
 The partition to watch. If empty, it will watch explicitly all partitions.
 
@@ -49,6 +52,7 @@ receivers:
   azureeventhub:
     connection: Endpoint=sb://namespace.servicebus.windows.net/;SharedAccessKeyName=RootManageSharedAccessKey;SharedAccessKey=superSecret1234=;EntityPath=hubName
     partition: foo
+    group: bar
     offset: "1234-5566"
     format: "azure"
 ```

receiver/azureeventhubreceiver/config.go

@@ -25,11 +25,12 @@ var (
 )
 
 type Config struct {
-	Connection string        `mapstructure:"connection"`
-	Partition  string        `mapstructure:"partition"`
-	Offset     string        `mapstructure:"offset"`
-	StorageID  *component.ID `mapstructure:"storage"`
-	Format     string        `mapstructure:"format"`
+	Connection    string        `mapstructure:"connection"`
+	Partition     string        `mapstructure:"partition"`
+	Offset        string        `mapstructure:"offset"`
+	StorageID     *component.ID `mapstructure:"storage"`
+	Format        string        `mapstructure:"format"`
+	ConsumerGroup string        `mapstructure:"group"`
 }
 
 func isValidFormat(format string) bool {

receiver/azureeventhubreceiver/eventhubhandler.go

@@ -131,12 +131,18 @@ func (h *eventhubHandler) run(ctx context.Context, host component.Host) error {
 
 func (h *eventhubHandler) setUpOnePartition(ctx context.Context, partitionID string, applyOffset bool) error {
 
-	offsetOption := eventhub.ReceiveWithLatestOffset()
+	receiverOptions := []eventhub.ReceiveOption{}
 	if applyOffset && h.config.Offset != "" {
-		offsetOption = eventhub.ReceiveWithStartingOffset(h.config.Offset)
+		receiverOptions = append(receiverOptions, eventhub.ReceiveWithStartingOffset(h.config.Offset))
+	} else {
+		receiverOptions = append(receiverOptions, eventhub.ReceiveWithLatestOffset())
+	}
+
+	if h.config.ConsumerGroup != "" {
+		receiverOptions = append(receiverOptions, eventhub.ReceiveWithConsumerGroup(h.config.ConsumerGroup))
 	}
 
-	handle, err := h.hub.Receive(ctx, partitionID, h.newMessageHandler, offsetOption)
+	handle, err := h.hub.Receive(ctx, partitionID, h.newMessageHandler, receiverOptions...)
 	if err != nil {
 		return err
 	}