[Feature] Introduce elasticsearch alias resource with atomic write index management and nested attributes

docs/resources/elasticsearch_alias.md

@@ -0,0 +1,61 @@
+
+---
+# generated by https://github.com/hashicorp/terraform-plugin-docs
+page_title: "elasticstack_elasticsearch_alias Resource - terraform-provider-elasticstack"
+subcategory: "Elasticsearch"
+description: |-
+  Manages an Elasticsearch alias. See, https://www.elastic.co/guide/en/elasticsearch/reference/current/indices-aliases.html
+---
+
+# elasticstack_elasticsearch_alias (Resource)
+
+Manages an Elasticsearch alias. See, https://www.elastic.co/guide/en/elasticsearch/reference/current/indices-aliases.html
+
+
+
+<!-- schema generated by tfplugindocs -->
+## Schema
+
+### Required
+
+- `name` (String) The alias name.
+
+### Optional
+
+- `read_indices` (Block Set) Set of read indices for the alias. (see [below for nested schema](#nestedblock--read_indices))
+- `write_index` (Block, Optional) The write index for the alias. Only one write index is allowed per alias. (see [below for nested schema](#nestedblock--write_index))
+
+### Read-Only
+
+- `id` (String) Generated ID of the alias resource.
+
+<a id="nestedblock--read_indices"></a>
+### Nested Schema for `read_indices`
+
+Required:
+
+- `name` (String) Name of the read index.
+
+Optional:
+
+- `filter` (String) Query used to limit documents the alias can access.
+- `index_routing` (String) Value used to route indexing operations to a specific shard.
+- `is_hidden` (Boolean) If true, the alias is hidden.
+- `routing` (String) Value used to route indexing and search operations to a specific shard.
+- `search_routing` (String) Value used to route search operations to a specific shard.
+
+
+<a id="nestedblock--write_index"></a>
+### Nested Schema for `write_index`
+
+Required:
+
+- `name` (String) Name of the write index.
+
+Optional:
+
+- `filter` (String) Query used to limit documents the alias can access.
+- `index_routing` (String) Value used to route indexing operations to a specific shard.
+- `is_hidden` (Boolean) If true, the alias is hidden.
+- `routing` (String) Value used to route indexing and search operations to a specific shard.
+- `search_routing` (String) Value used to route search operations to a specific shard.

internal/clients/elasticsearch/index.go

@@ -581,6 +581,246 @@ func DeleteDataStreamLifecycle(ctx context.Context, apiClient *clients.ApiClient
 	return nil
 }
 
+func GetAlias(ctx context.Context, apiClient *clients.ApiClient, aliasName string) (map[string]models.Index, fwdiags.Diagnostics) {
+	esClient, err := apiClient.GetESClient()
+	if err != nil {
+		return nil, fwdiags.Diagnostics{
+			fwdiags.NewErrorDiagnostic(err.Error(), err.Error()),
+		}
+	}
+
+	res, err := esClient.Indices.GetAlias(
+		esClient.Indices.GetAlias.WithName(aliasName),
+		esClient.Indices.GetAlias.WithContext(ctx),
+	)
+	if err != nil {
+		return nil, fwdiags.Diagnostics{
+			fwdiags.NewErrorDiagnostic(err.Error(), err.Error()),
+		}
+	}
+	defer res.Body.Close()
+
+	if res.StatusCode == http.StatusNotFound {
+		return nil, nil
+	}
+
+	diags := diagutil.CheckError(res, fmt.Sprintf("Unable to get alias '%s'", aliasName))
+	if diagutil.FrameworkDiagsFromSDK(diags).HasError() {
+		return nil, diagutil.FrameworkDiagsFromSDK(diags)
+	}
+
+	indices := make(map[string]models.Index)
+	if err := json.NewDecoder(res.Body).Decode(&indices); err != nil {
+		return nil, fwdiags.Diagnostics{
+			fwdiags.NewErrorDiagnostic(err.Error(), err.Error()),
+		}
+	}
+
+	return indices, nil
+}
+
+func PutAlias(ctx context.Context, apiClient *clients.ApiClient, aliasName string, indices []string, alias *models.IndexAlias) fwdiags.Diagnostics {
+	esClient, err := apiClient.GetESClient()
+	if err != nil {
+		return fwdiags.Diagnostics{
+			fwdiags.NewErrorDiagnostic(err.Error(), err.Error()),
+		}
+	}
+
+	// Build the request body for index aliases API
+	var actions []map[string]interface{}
+
+	for _, index := range indices {
+		addAction := map[string]interface{}{
+			"add": map[string]interface{}{
+				"index": index,
+				"alias": aliasName,
+			},
+		}
+
+		// Only include non-empty optional fields in the add action
+		addActionDetails := addAction["add"].(map[string]interface{})
+
+		if alias.Filter != nil {
+			addActionDetails["filter"] = alias.Filter
+		}
+		if alias.IndexRouting != "" {
+			addActionDetails["index_routing"] = alias.IndexRouting
+		}
+		if alias.SearchRouting != "" {
+			addActionDetails["search_routing"] = alias.SearchRouting
+		}
+		if alias.Routing != "" {
+			addActionDetails["routing"] = alias.Routing
+		}
+		if alias.IsHidden {
+			addActionDetails["is_hidden"] = alias.IsHidden
+		}
+		if alias.IsWriteIndex {
+			addActionDetails["is_write_index"] = alias.IsWriteIndex
+		}
+
+		actions = append(actions, addAction)
+	}
+
+	aliasActions := map[string]interface{}{
+		"actions": actions,
+	}
+
+	aliasBytes, err := json.Marshal(aliasActions)
+	if err != nil {
+		return fwdiags.Diagnostics{
+			fwdiags.NewErrorDiagnostic(err.Error(), err.Error()),
+		}
+	}
+
+	res, err := esClient.Indices.UpdateAliases(
+		bytes.NewReader(aliasBytes),
+		esClient.Indices.UpdateAliases.WithContext(ctx),
+	)
+	if err != nil {
+		return fwdiags.Diagnostics{
+			fwdiags.NewErrorDiagnostic(err.Error(), err.Error()),
+		}
+	}
+	defer res.Body.Close()
+
+	diags := diagutil.CheckError(res, fmt.Sprintf("Unable to create/update alias '%s'", aliasName))
+	return diagutil.FrameworkDiagsFromSDK(diags)
+}
+
+func DeleteAlias(ctx context.Context, apiClient *clients.ApiClient, aliasName string, indices []string) fwdiags.Diagnostics {
+	esClient, err := apiClient.GetESClient()
+	if err != nil {
+		return fwdiags.Diagnostics{
+			fwdiags.NewErrorDiagnostic(err.Error(), err.Error()),
+		}
+	}
+
+	// Use UpdateAliases API for deletion to handle multiple indices
+	aliasActions := map[string]interface{}{
+		"actions": []map[string]interface{}{
+			{
+				"remove": map[string]interface{}{
+					"indices": indices,
+					"alias":   aliasName,
+				},
+			},
+		},
+	}
+
+	aliasBytes, err := json.Marshal(aliasActions)
+	if err != nil {
+		return fwdiags.Diagnostics{
+			fwdiags.NewErrorDiagnostic(err.Error(), err.Error()),
+		}
+	}
+
+	res, err := esClient.Indices.UpdateAliases(
+		bytes.NewReader(aliasBytes),
+		esClient.Indices.UpdateAliases.WithContext(ctx),
+	)
+	if err != nil {
+		return fwdiags.Diagnostics{
+			fwdiags.NewErrorDiagnostic(err.Error(), err.Error()),
+		}
+	}
+	defer res.Body.Close()
+
+	diags := diagutil.CheckError(res, fmt.Sprintf("Unable to delete alias '%s'", aliasName))
+	return diagutil.FrameworkDiagsFromSDK(diags)
+}
+
+// AliasAction represents a single action in an atomic alias update operation
+type AliasAction struct {
+	Type          string // "add" or "remove"
+	Index         string
+	Alias         string
+	IsWriteIndex  bool
+	Filter        map[string]interface{}
+	IndexRouting  string
+	IsHidden      bool
+	Routing       string
+	SearchRouting string
+}
+
+// UpdateAliasesAtomic performs atomic alias updates using multiple actions
+func UpdateAliasesAtomic(ctx context.Context, apiClient *clients.ApiClient, actions []AliasAction) fwdiags.Diagnostics {
+	esClient, err := apiClient.GetESClient()
+	if err != nil {
+		return fwdiags.Diagnostics{
+			fwdiags.NewErrorDiagnostic(err.Error(), err.Error()),
+		}
+	}
+
+	var aliasActions []map[string]interface{}
+
+	for _, action := range actions {
+		switch action.Type {
+		case "remove":
+			aliasActions = append(aliasActions, map[string]interface{}{
+				"remove": map[string]interface{}{
+					"index": action.Index,
+					"alias": action.Alias,
+				},
+			})
+		case "add":
+			addDetails := map[string]interface{}{
+				"index": action.Index,
+				"alias": action.Alias,
+			}
+
+			if action.IsWriteIndex {
+				addDetails["is_write_index"] = true
+			}
+			if action.Filter != nil {
+				addDetails["filter"] = action.Filter
+			}
+			if action.IndexRouting != "" {
+				addDetails["index_routing"] = action.IndexRouting
+			}
+			if action.SearchRouting != "" {
+				addDetails["search_routing"] = action.SearchRouting
+			}
+			if action.Routing != "" {
+				addDetails["routing"] = action.Routing
+			}
+			if action.IsHidden {
+				addDetails["is_hidden"] = action.IsHidden
+			}
+
+			aliasActions = append(aliasActions, map[string]interface{}{
+				"add": addDetails,
+			})
+		}
+	}
+
+	requestBody := map[string]interface{}{
+		"actions": aliasActions,
+	}
+
+	aliasBytes, err := json.Marshal(requestBody)
+	if err != nil {
+		return fwdiags.Diagnostics{
+			fwdiags.NewErrorDiagnostic(err.Error(), err.Error()),
+		}
+	}
+
+	res, err := esClient.Indices.UpdateAliases(
+		bytes.NewReader(aliasBytes),
+		esClient.Indices.UpdateAliases.WithContext(ctx),
+	)
+	if err != nil {
+		return fwdiags.Diagnostics{
+			fwdiags.NewErrorDiagnostic(err.Error(), err.Error()),
+		}
+	}
+	defer res.Body.Close()
+
+	diags := diagutil.CheckError(res, "Unable to update aliases atomically")
+	return diagutil.FrameworkDiagsFromSDK(diags)
+}
+
 func PutIngestPipeline(ctx context.Context, apiClient *clients.ApiClient, pipeline *models.IngestPipeline) diag.Diagnostics {
 	var diags diag.Diagnostics
 	pipelineBytes, err := json.Marshal(pipeline)