Mapping context and strategy resolution

The [Entity<>] attribute on your mapping context drives everything the channel does: what kind of Elasticsearch target to create, which templates to put in place, how to format bulk operations, and how to manage aliases. This page is the complete reference for how [Entity<>] parameters map to channel behavior.

Simplest form

		[ElasticsearchMappingContext]
[Entity<Product>]
public static partial class MyContext;
		
	

With no parameters, [Entity<Product>] defaults to:

Target: EntityTarget.Index
Name: product (type name, lowercased)
No aliases, no date pattern, no data stream settings

Entity targets

The Target parameter determines the fundamental ingestion strategy:

		// Index (default) -- mutable documents, upserts, aliases
[Entity<Product>]
[Entity<Product>(Target = EntityTarget.Index)]

// Data stream -- append-only, automatic rollover
[Entity<LogEntry>(Target = EntityTarget.DataStream,
    DataStreamType = "logs", DataStreamDataset = "myapp")]

// Wired stream -- serverless managed, no local bootstrap
[Entity<LogEntry>(Target = EntityTarget.WiredStream)]
		
	

Strategy resolution by target

	Index	DataStream	WiredStream
Ingest	`TypeContextIndexIngestStrategy`	`DataStreamIngestStrategy`	`WiredStreamIngestStrategy`
Bulk operation	`index` (upsert)	`create` (append)	`create` (append)
Bootstrap	Component + index templates	Component + data stream templates	No-op
Provisioning	Hash-based reuse or always create	Always create	Always create
Alias	Configured or none	None	None

Document attributes

Attributes on your document class further refine the resolved strategy:

Attribute	Effect on strategy
`[Id]`	Bulk headers include `_id` field, enabling upserts instead of blind inserts
`[Timestamp]`	Required for data streams. Used for date-based index naming when `DatePattern` is set
`[ContentHash]`	Enables `HashBasedReuseProvisioning` -- the channel checks if the existing index has the same schema hash and reuses it instead of creating a new one
`[Keyword]`	Maps to `keyword` field type in the component template
`[Text]`	Maps to `text` field type in the component template
`[Dimension]`	Marks a TSDB dimension field (requires `DataStreamMode = DataStreamMode.Tsdb`)

Index parameters

For EntityTarget.Index, these parameters control index naming and alias management:

		[Entity<Product>(
    Target = EntityTarget.Index,
    Name = "products",
    WriteAlias = "products",
    ReadAlias = "products-search",
    SearchPattern = "products-*",
    DatePattern = "yyyy.MM.dd.HHmmss"
)]
		
	

Index name (default: type name lowercased)
Write alias for zero-downtime rotation
Search alias spanning all indices
Glob pattern matching all indices
Time-stamped index names

Parameter	Default	Effect
`Name`	Type name lowercased	Base index name
`WriteAlias`	None	Enables `LatestAndSearchAliasStrategy`
`ReadAlias`	None	Search alias spanning all matching indices
`SearchPattern`	None	Glob for matching indices in alias operations
`DatePattern`	None	Creates time-stamped index names (e.g. `products-2026.02.15.120000`)
`Shards`	-1 (omitted)	Number of primary shards
`Replicas`	-1 (omitted)	Number of replica shards
`RefreshInterval`	None	Index refresh interval

Alias strategy resolution

WriteAlias	ReadAlias	Strategy
Not set	Not set	`NoAliasStrategy`
Set	Set	`LatestAndSearchAliasStrategy` -- swaps write alias to latest index, search alias spans all

Data stream parameters

For EntityTarget.DataStream, these parameters control the data stream naming convention {type}-{dataset}-{namespace}:

		[Entity<LogEntry>(
    Target = EntityTarget.DataStream,
    DataStreamType = "logs",
    DataStreamDataset = "myapp",
    DataStreamNamespace = "production",   // Default: "default"
    DataStreamMode = DataStreamMode.Tsdb
)]
		
	

Required: logs, metrics, traces, etc.
Required: source identifier
Default: DataStreamMode.Default

Parameter	Default	Effect
`DataStreamType`	Required	Data category (`logs`, `metrics`, `traces`)
`DataStreamDataset`	Required	Source identifier
`DataStreamNamespace`	`"default"`	Environment (`production`, `staging`)
`DataStreamMode`	`Default`	`Default`, `LogsDb`, or `Tsdb`

Data stream name: {type}-{dataset}-{namespace} (e.g. logs-myapp-production)

Variants

Use Variant to define multiple index configurations for the same document type:

		[ElasticsearchMappingContext]
[Entity<Article>(
    Target = EntityTarget.Index,
    Name = "articles-lexical",
    WriteAlias = "articles-lexical",
    ReadAlias = "articles-lexical-search",
    SearchPattern = "articles-lexical-*",
    DatePattern = "yyyy.MM.dd.HHmmss"
)]
[Entity<Article>(
    Target = EntityTarget.Index,
    Name = "articles-semantic",
    Variant = "Semantic",
    WriteAlias = "articles-semantic",
    ReadAlias = "articles-semantic-search",
    SearchPattern = "articles-semantic-*",
    DatePattern = "yyyy.MM.dd.HHmmss"
)]
public static partial class ArticleContext;
		
	

This generates:

ArticleContext.Article.Context (lexical, default variant)
ArticleContext.ArticleSemantic.Context (semantic variant)

Use variants with IncrementalSyncOrchestrator to coordinate multiple indices over the same data. See semantic enrichment for an end-to-end example.

Overriding inferred strategies

When the auto-resolved strategy isn't enough, use the IngestStrategies and BootstrapStrategies factory methods:

		// Add 30-day retention to a data stream
var strategy = IngestStrategies.DataStream<LogEntry>(context, "30d");
var options = new IngestChannelOptions<LogEntry>(transport, strategy, context);

// Add ILM to an index
var strategy = IngestStrategies.Index<Product>(context,
    BootstrapStrategies.IndexWithIlm("products-policy"));
var options = new IngestChannelOptions<Product>(transport, strategy, context);
		
	

See strategies for the complete factory method reference.