Add Feature cat fielddata API (olivere#1476)

This commit adds the Cat Fielddata API and test cases.

cat_fielddata.go

@@ -0,0 +1,211 @@
+// Copyright 2012-present Oliver Eilhard. All rights reserved.
+// Use of this source code is governed by a MIT-license.
+// See http://olivere.mit-license.org/license.txt for details.
+
+package elastic
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"net/url"
+	"strings"
+
+	"github.com/olivere/elastic/v7/uritemplates"
+)
+
+// CatFielddataService Returns the amount of heap memory currently used by
+// the field data cache on every data node in the cluster.
+//
+// See https://www.elastic.co/guide/en/elasticsearch/reference/7.12/cat-fielddata.html
+// for details.
+type CatFielddataService struct {
+	client *Client
+
+	pretty     *bool       // pretty format the returned JSON response
+	human      *bool       // return human readable values for statistics
+	errorTrace *bool       // include the stack trace of returned errors
+	filterPath []string    // list of filters used to reduce the response
+	headers    http.Header // custom request-level HTTP headers
+
+	fields  []string // list of fields used to limit returned information
+	bytes   string   // b, k, m, or g
+	columns []string
+	sort    []string // list of columns for sort order
+}
+
+// NewCatFielddataService creates a new NewCatFielddataService.
+func NewCatFielddataService(client *Client) *CatFielddataService {
+	return &CatFielddataService{
+		client: client,
+	}
+}
+
+// Pretty tells Elasticsearch whether to return a formatted JSON response.
+func (s *CatFielddataService) Pretty(pretty bool) *CatFielddataService {
+	s.pretty = &pretty
+	return s
+}
+
+// Human specifies whether human readable values should be returned in
+// the JSON response, e.g. "7.5mb".
+func (s *CatFielddataService) Human(human bool) *CatFielddataService {
+	s.human = &human
+	return s
+}
+
+// ErrorTrace specifies whether to include the stack trace of returned errors.
+func (s *CatFielddataService) ErrorTrace(errorTrace bool) *CatFielddataService {
+	s.errorTrace = &errorTrace
+	return s
+}
+
+// FilterPath specifies a list of filters used to reduce the response.
+func (s *CatFielddataService) FilterPath(filterPath ...string) *CatFielddataService {
+	s.filterPath = filterPath
+	return s
+}
+
+// Header adds a header to the request.
+func (s *CatFielddataService) Header(name string, value string) *CatFielddataService {
+	if s.headers == nil {
+		s.headers = http.Header{}
+	}
+	s.headers.Add(name, value)
+	return s
+}
+
+// Headers specifies the headers of the request.
+func (s *CatFielddataService) Headers(headers http.Header) *CatFielddataService {
+	s.headers = headers
+	return s
+}
+
+// Fielddata specifies one or more node IDs to for information should be returned.
+func (s *CatFielddataService) Field(fields ...string) *CatFielddataService {
+	s.fields = fields
+	return s
+}
+
+// Bytes represents the unit in which to display byte values.
+// Valid values are: "b", "k", "m", or "g".
+func (s *CatFielddataService) Bytes(bytes string) *CatFielddataService {
+	s.bytes = bytes
+	return s
+}
+
+// Columns to return in the response.
+// To get a list of all possible columns to return, run the following command
+// in your terminal:
+//
+// Example:
+//   curl 'http://localhost:9200/_cat/fielddata?help'
+//
+// You can use Columns("*") to return all possible columns. That might take
+// a little longer than the default set of columns.
+func (s *CatFielddataService) Columns(columns ...string) *CatFielddataService {
+	s.columns = columns
+	return s
+}
+
+// Sort is a list of fields to sort by.
+func (s *CatFielddataService) Sort(fields ...string) *CatFielddataService {
+	s.sort = fields
+	return s
+}
+
+func (s *CatFielddataService) buildURL() (string, url.Values, error) {
+	// Build URL
+	var (
+		path string
+		err  error
+	)
+
+	if len(s.fields) > 0 {
+		path, err = uritemplates.Expand("/_cat/fielddata/{field}", map[string]string{
+			"field": strings.Join(s.fields, ","),
+		})
+	} else {
+		path = "/_cat/fielddata/"
+	}
+	if err != nil {
+		return "", url.Values{}, err
+	}
+
+	// Add query string parameters
+	params := url.Values{
+		"format": []string{"json"}, // always returns as JSON
+	}
+	if v := s.pretty; v != nil {
+		params.Set("pretty", fmt.Sprint(*v))
+	}
+	if v := s.human; v != nil {
+		params.Set("human", fmt.Sprint(*v))
+	}
+	if v := s.errorTrace; v != nil {
+		params.Set("error_trace", fmt.Sprint(*v))
+	}
+	if len(s.filterPath) > 0 {
+		params.Set("filter_path", strings.Join(s.filterPath, ","))
+	}
+	if s.bytes != "" {
+		params.Set("bytes", s.bytes)
+	}
+	if len(s.sort) > 0 {
+		params.Set("s", strings.Join(s.sort, ","))
+	}
+	if len(s.columns) > 0 {
+		params.Set("h", strings.Join(s.columns, ","))
+	}
+	return path, params, nil
+}
+
+// Do executes the operation.
+func (s *CatFielddataService) Do(ctx context.Context) (CatFielddataResponse, error) {
+	// Get URL for request
+	path, params, err := s.buildURL()
+	if err != nil {
+		return nil, err
+	}
+
+	// Get HTTP response
+	res, err := s.client.PerformRequest(ctx, PerformRequestOptions{
+		Method:  "GET",
+		Path:    path,
+		Params:  params,
+		Headers: s.headers,
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	// Return operation response
+	var ret CatFielddataResponse
+	if err := s.client.decoder.Decode(res.Body, &ret); err != nil {
+		return nil, err
+	}
+	return ret, nil
+}
+
+// -- Result of a get request.
+
+// CatFielddataResponse is the outcome of CatFielddataService.Do.
+type CatFielddataResponse []CatFielddataResponseRow
+
+// CatFielddataResponseRow is a single row in a CatFielddataResponse.
+// Notice that not all of these fields might be filled; that depends on
+// the number of columns chose in the request (see CatFielddataService.Columns).
+type CatFielddataResponseRow struct {
+	// Id represents the id of the fielddata.
+	Id string `json:"id"`
+	// Host represents the hostname of the fielddata.
+	Host string `json:"host"`
+	// IP represents the IP address of the fielddata.
+	IP string `json:"ip"`
+	// Node represents the Node name of the fielddata.
+	Node string `json:"node"`
+	// Field represents the name of the fielddata.
+	Field string `json:"field"`
+	// Size represents the size of the fielddata, e.g. "53.2gb".
+	Size string `json:"size"`
+}

cat_fieldddata_test.go

@@ -0,0 +1,49 @@
+// Copyright 2012-present Oliver Eilhard. All rights reserved.
+// Use of this source code is governed by a MIT-license.
+// See http://olivere.mit-license.org/license.txt for details.
+
+package elastic
+
+import (
+	"context"
+	"testing"
+)
+
+func TestCatFielddata(t *testing.T) {
+	client := setupTestClientAndCreateIndexAndAddDocs(t, SetDecoder(&strictDecoder{})) // , SetTraceLog(log.New(os.Stdout, "", 0)))
+	ctx := context.Background()
+
+	// generate fielddata by aggregation
+	aggRes, err := client.Search(testIndexName).
+		Aggregation("gene_message_fielddata", NewTermsAggregation().Field("message")).Do(ctx)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if aggRes == nil {
+		t.Fatal("want response, have nil")
+	}
+
+	res, err := client.CatFielddata().Pretty(true).Columns("*").Do(ctx)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if res == nil {
+		t.Fatal("want response, have nil")
+	}
+	if len(res) == 0 {
+		t.Fatalf("want response, have: %v", res)
+	}
+
+	// check fielddata "message" in response
+	exist := false
+	for _, fielddata := range res {
+		if fielddata.Field == "message" {
+			exist = true
+			break
+		}
+	}
+	if !exist {
+		t.Fatal("fielddata message not found")
+	}
+
+}

client.go

@@ -1861,7 +1861,6 @@ func (c *Client) GetFieldMapping() *IndicesGetFieldMappingService {
 
 // -- cat APIs --
 
-// TODO cat fielddata
 // TODO cat master
 // TODO cat nodes
 // TODO cat pending tasks
@@ -1871,6 +1870,11 @@ func (c *Client) GetFieldMapping() *IndicesGetFieldMappingService {
 // TODO cat shards
 // TODO cat segments
 
+// CatFielddata returns information about the amount of heap memory currently used by the field data cache.
+func (c *Client) CatFielddata() *CatFielddataService {
+	return NewCatFielddataService(c)
+}
+
 // CatAliases returns information about aliases.
 func (c *Client) CatAliases() *CatAliasesService {
 	return NewCatAliasesService(c)