wip: Elasticsearch 2.0

* Bump version to 3.0.0
* Change all `Source()` methods to also return an error.
* Remove facets
* Remove Delete Mapping API
* Add `meta` to all aggregations
* Field `status` is removed from HTTP GET response. It already exists
  in the HTTP header.
* Remove `_fields` from Get API. It is `fields`.
* Fix test mappings, e.g. remove `store` from `_ttl` and `_timestamp`.
* Make `MoreLikeThisQuery` compatible with 2.0.
* Remove `MoreLikeThisFieldQuery`.

alias.go

@@ -78,7 +78,11 @@ func (s *AliasService) Do() (*AliasResult, error) {
 		detailsJson["index"] = action.Index
 		detailsJson["alias"] = action.Alias
 		if action.Filter != nil {
-			detailsJson["filter"] = (*action.Filter).Source()
+			src, err := (*action.Filter).Source()
+			if err != nil {
+				return nil, err
+			}
+			detailsJson["filter"] = src
 		}
 		actionJson[action.Type] = detailsJson
 		actionsJson = append(actionsJson, actionJson)

client.go

@@ -22,7 +22,7 @@ import (
 
 const (
 	// Version is the current version of Elastic.
-	Version = "2.0.0"
+	Version = "3.0.0"
 
 	// DefaultUrl is the default endpoint of Elasticsearch on the local machine.
 	// It is used e.g. when initializing a new Client without a specific URL.
@@ -1198,11 +1198,6 @@ func (c *Client) PutMapping() *PutMappingService {
 	return NewPutMappingService(c)
 }
 
-// DeleteMapping deletes a mapping.
-func (c *Client) DeleteMapping() *DeleteMappingService {
-	return NewDeleteMappingService(c)
-}
-
 // ClusterHealth retrieves the health of the cluster.
 func (c *Client) ClusterHealth() *ClusterHealthService {
 	return NewClusterHealthService(c)

client_test.go

@@ -482,8 +482,8 @@ func TestPerformRequest(t *testing.T) {
 	if err := json.Unmarshal(res.Body, ret); err != nil {
 		t.Fatalf("expected no error on decode; got: %v", err)
 	}
-	if ret.Status != 200 {
-		t.Errorf("expected HTTP status 200; got: %d", ret.Status)
+	if ret.ClusterName == "" {
+		t.Errorf("expected cluster name; got: %q", ret.ClusterName)
 	}
 }
 
@@ -508,8 +508,8 @@ func TestPerformRequestWithLogger(t *testing.T) {
 	if err := json.Unmarshal(res.Body, ret); err != nil {
 		t.Fatalf("expected no error on decode; got: %v", err)
 	}
-	if ret.Status != 200 {
-		t.Errorf("expected HTTP status 200; got: %d", ret.Status)
+	if ret.ClusterName == "" {
+		t.Errorf("expected cluster name; got: %q", ret.ClusterName)
 	}
 
 	got := w.String()
@@ -547,8 +547,8 @@ func TestPerformRequestWithLoggerAndTracer(t *testing.T) {
 	if err := json.Unmarshal(res.Body, ret); err != nil {
 		t.Fatalf("expected no error on decode; got: %v", err)
 	}
-	if ret.Status != 200 {
-		t.Errorf("expected HTTP status 200; got: %d", ret.Status)
+	if ret.ClusterName == "" {
+		t.Errorf("expected cluster name; got: %q", ret.ClusterName)
 	}
 
 	lgot := lw.String()

count.go

@@ -128,8 +128,12 @@ func (s *CountService) Do() (int64, error) {
 	// Set body if there is a query specified
 	var body interface{}
 	if s.query != nil {
+		src, err := s.query.Source()
+		if err != nil {
+			return 0, err
+		}
 		query := make(map[string]interface{})
-		query["query"] = s.query.Source()
+		query["query"] = src
 		body = query
 	}
 

delete_by_query.go

@@ -261,8 +261,12 @@ func (s *DeleteByQueryService) Do() (*DeleteByQueryResult, error) {
 	// Set body if there is a query set
 	var body interface{}
 	if s.query != nil {
+		src, err := s.query.Source()
+		if err != nil {
+			return nil, err
+		}
 		query := make(map[string]interface{})
-		query["query"] = s.query.Source()
+		query["query"] = src
 		body = query
 	}
 

errors_test.go

@@ -12,7 +12,7 @@ func TestResponseError(t *testing.T) {
 	message := "Something went seriously wrong."
 	raw := "HTTP/1.1 500 Internal Server Error\r\n" +
 		"\r\n" +
-		`{"status":500,"error":"` + message + `"}` + "\r\n"
+		`{"error":"` + message + `"}` + "\r\n"
 	r := bufio.NewReader(strings.NewReader(raw))
 
 	resp, err := http.ReadResponse(r, nil)

explain.go

@@ -183,8 +183,13 @@ func (s *ExplainService) Pretty(pretty bool) *ExplainService {
 
 // Query sets a query definition using the Query DSL.
 func (s *ExplainService) Query(query Query) *ExplainService {
+	src, err := query.Source()
+	if err != nil {
+		// Do nothing in case of an error
+		return s
+	}
 	body := make(map[string]interface{})
-	body["query"] = query.Source()
+	body["query"] = src
 	s.bodyJson = body
 	return s
 }

fetch_source_context.go

@@ -47,14 +47,14 @@ func (fsc *FetchSourceContext) TransformSource(transformSource bool) *FetchSourc
 	return fsc
 }
 
-func (fsc *FetchSourceContext) Source() interface{} {
+func (fsc *FetchSourceContext) Source() (interface{}, error) {
 	if !fsc.fetchSource {
-		return false
+		return false, nil
 	}
 	return map[string]interface{}{
 		"includes": fsc.includes,
 		"excludes": fsc.excludes,
-	}
+	}, nil
 }
 
 // Query returns the parameters in a form suitable for a URL query string.

fetch_source_context_test.go

@@ -11,7 +11,11 @@ import (
 
 func TestFetchSourceContextNoFetchSource(t *testing.T) {
 	builder := NewFetchSourceContext(false)
-	data, err := json.Marshal(builder.Source())
+	src, err := builder.Source()
+	if err != nil {
+		t.Fatal(err)
+	}
+	data, err := json.Marshal(src)
 	if err != nil {
 		t.Fatalf("marshaling to JSON failed: %v", err)
 	}
@@ -24,7 +28,11 @@ func TestFetchSourceContextNoFetchSource(t *testing.T) {
 
 func TestFetchSourceContextNoFetchSourceIgnoreIncludesAndExcludes(t *testing.T) {
 	builder := NewFetchSourceContext(false).Include("a", "b").Exclude("c")
-	data, err := json.Marshal(builder.Source())
+	src, err := builder.Source()
+	if err != nil {
+		t.Fatal(err)
+	}
+	data, err := json.Marshal(src)
 	if err != nil {
 		t.Fatalf("marshaling to JSON failed: %v", err)
 	}
@@ -37,7 +45,11 @@ func TestFetchSourceContextNoFetchSourceIgnoreIncludesAndExcludes(t *testing.T)
 
 func TestFetchSourceContextFetchSource(t *testing.T) {
 	builder := NewFetchSourceContext(true)
-	data, err := json.Marshal(builder.Source())
+	src, err := builder.Source()
+	if err != nil {
+		t.Fatal(err)
+	}
+	data, err := json.Marshal(src)
 	if err != nil {
 		t.Fatalf("marshaling to JSON failed: %v", err)
 	}
@@ -50,7 +62,11 @@ func TestFetchSourceContextFetchSource(t *testing.T) {
 
 func TestFetchSourceContextFetchSourceWithIncludesAndExcludes(t *testing.T) {
 	builder := NewFetchSourceContext(true).Include("a", "b").Exclude("c")
-	data, err := json.Marshal(builder.Source())
+	src, err := builder.Source()
+	if err != nil {
+		t.Fatal(err)
+	}
+	data, err := json.Marshal(src)
 	if err != nil {
 		t.Fatalf("marshaling to JSON failed: %v", err)
 	}

filter.go

@@ -4,6 +4,8 @@
 
 package elastic
 
+// Filter defines the contract each filter has to fulfill.
 type Filter interface {
-	Source() interface{}
+	// Source returns a JSON-serializable fragment of the request.
+	Source() (interface{}, error)
 }

get.go

@@ -180,9 +180,6 @@ func (b *GetService) Do() (*GetResult, error) {
 	if b.ignoreErrorsOnGeneratedFields != nil {
 		params.Add("ignore_errors_on_generated_fields", fmt.Sprintf("%v", *b.ignoreErrorsOnGeneratedFields))
 	}
-	if len(b.fields) > 0 {
-		params.Add("_fields", strings.Join(b.fields, ","))
-	}
 	if b.version != nil {
 		params.Add("version", fmt.Sprintf("%d", *b.version))
 	}