Merge pull request #69 from arangodb/response-header

Adding Response.Header(string) & tests

Author: ewoutp

connection.go

@@ -91,6 +91,10 @@ type Response interface {
 	// If so, nil is returned.
 	// If not, an attempt is made to parse an error response in the body and an error is returned.
 	CheckStatus(validStatusCodes ...int) error
+	// Header returns the value of a response header with given key.
+	// If no such header is found, an empty string is returned.
+	// On nested Response's, this function will always return an empty string.
+	Header(key string) string
 	// ParseBody performs protocol specific unmarshalling of the response data into the given result.
 	// If the given field is non-empty, the contents of that field will be parsed into the given result.
 	// This can only be used for requests that return a single object.

http/response_json.go

@@ -77,6 +77,12 @@ func (r *httpJSONResponse) CheckStatus(validStatusCodes ...int) error {
 	}
 }
 
+// Header returns the value of a response header with given key.
+// If no such header is found, an empty string is returned.
+func (r *httpJSONResponse) Header(key string) string {
+	return r.resp.Header.Get(key)
+}
+
 // ParseBody performs protocol specific unmarshalling of the response data into the given result.
 // If the given field is non-empty, the contents of that field will be parsed into the given result.
 func (r *httpJSONResponse) ParseBody(field string, result interface{}) error {

http/response_json_element.go

@@ -89,6 +89,12 @@ func (r *httpJSONResponseElement) CheckStatus(validStatusCodes ...int) error {
 	}
 }
 
+// Header returns the value of a response header with given key.
+// If no such header is found, an empty string is returned.
+func (r *httpJSONResponseElement) Header(key string) string {
+	return ""
+}
+
 // ParseBody performs protocol specific unmarshalling of the response data into the given result.
 // If the given field is non-empty, the contents of that field will be parsed into the given result.
 func (r *httpJSONResponseElement) ParseBody(field string, result interface{}) error {

http/response_vpack.go

@@ -75,6 +75,12 @@ func (r *httpVPackResponse) CheckStatus(validStatusCodes ...int) error {
 	}
 }
 
+// Header returns the value of a response header with given key.
+// If no such header is found, an empty string is returned.
+func (r *httpVPackResponse) Header(key string) string {
+	return r.resp.Header.Get(key)
+}
+
 // ParseBody performs protocol specific unmarshalling of the response data into the given result.
 // If the given field is non-empty, the contents of that field will be parsed into the given result.
 func (r *httpVPackResponse) ParseBody(field string, result interface{}) error {

http/response_vpack_element.go

@@ -87,6 +87,12 @@ func (r *httpVPackResponseElement) CheckStatus(validStatusCodes ...int) error {
 	}
 }
 
+// Header returns the value of a response header with given key.
+// If no such header is found, an empty string is returned.
+func (r *httpVPackResponseElement) Header(key string) string {
+	return ""
+}
+
 // ParseBody performs protocol specific unmarshalling of the response data into the given result.
 // If the given field is non-empty, the contents of that field will be parsed into the given result.
 func (r *httpVPackResponseElement) ParseBody(field string, result interface{}) error {

test/client_test.go

@@ -27,6 +27,7 @@ import (
 	"crypto/tls"
 	httplib "net/http"
 	"os"
+	"strconv"
 	"strings"
 	"sync"
 	"testing"
@@ -163,7 +164,7 @@ func createClientFromEnv(t testEnv, waitUntilReady bool, connection ...*driver.C
 		t.Fatalf("Failed to create new client: %s", describe(err))
 	}
 	if waitUntilReady {
-		timeout := 3*time.Minute
+		timeout := 3 * time.Minute
 		ctx, cancel := context.WithTimeout(context.Background(), timeout)
 		defer cancel()
 		if up := waitUntilServerAvailable(ctx, c, t); !up {
@@ -244,7 +245,7 @@ func TestCreateClientHttpConnectionCustomTransport(t *testing.T) {
 	if err != nil {
 		t.Fatalf("Failed to create new client: %s", describe(err))
 	}
-	timeout := 3*time.Minute
+	timeout := 3 * time.Minute
 	ctx, cancel := context.WithTimeout(context.Background(), timeout)
 	defer cancel()
 	if up := waitUntilServerAvailable(ctx, c, t); !up {
@@ -256,3 +257,45 @@ func TestCreateClientHttpConnectionCustomTransport(t *testing.T) {
 		t.Logf("Got server version %s", info)
 	}
 }
+
+// TestResponseHeader checks the Response.Header function.
+func TestResponseHeader(t *testing.T) {
+	c := createClientFromEnv(t, true)
+	ctx := context.Background()
+
+	version, err := c.Version(nil)
+	if err != nil {
+		t.Fatalf("Version failed: %s", describe(err))
+	}
+	isv33p := version.Version.CompareTo("3.3") >= 0
+	if !isv33p {
+		t.Skip("This test requires version 3.3")
+	} else {
+		var resp driver.Response
+		db := ensureDatabase(ctx, c, "_system", nil, t)
+		col := ensureCollection(ctx, db, "response_header_test", nil, t)
+
+		// `ETag` header must contain the `_rev` of the new document in quotes.
+		doc := map[string]string{
+			"Test":   "TestResponseHeader",
+			"Intent": "Check Response.Header",
+		}
+		meta, err := col.CreateDocument(driver.WithResponse(ctx, &resp), doc)
+		if err != nil {
+			t.Fatalf("CreateDocument failed: %s", describe(err))
+		}
+		expectedETag := strconv.Quote(meta.Rev)
+		if x := resp.Header("ETag"); x != expectedETag {
+			t.Errorf("Unexpected result from Header('ETag'), got '%s', expected '%s'", x, expectedETag)
+		}
+		if x := resp.Header("Etag"); x != expectedETag {
+			t.Errorf("Unexpected result from Header('Etag'), got '%s', expected '%s'", x, expectedETag)
+		}
+		if x := resp.Header("etag"); x != expectedETag {
+			t.Errorf("Unexpected result from Header('etag'), got '%s', expected '%s'", x, expectedETag)
+		}
+		if x := resp.Header("ETAG"); x != expectedETag {
+			t.Errorf("Unexpected result from Header('ETAG'), got '%s', expected '%s'", x, expectedETag)
+		}
+	}
+}

vst/response.go

@@ -24,6 +24,8 @@ package vst
 
 import (
 	"fmt"
+	"strings"
+	"sync"
 
 	driver "github.com/arangodb/go-driver"
 	"github.com/arangodb/go-driver/vst/protocol"
@@ -36,6 +38,9 @@ type vstResponse struct {
 	Version      int
 	Type         int
 	ResponseCode int
+	meta         velocypack.Slice
+	metaMutex    sync.Mutex
+	metaMap      map[string]string
 	slice        velocypack.Slice
 	bodyArray    []driver.Response
 }
@@ -48,10 +53,13 @@ func newResponse(msg protocol.Message, endpoint string, rawResponse *[]byte) (*v
 		return nil, driver.WithStack(err)
 	}
 	//panic("hdr: " + hex.EncodeToString(hdr))
+	var hdrLen velocypack.ValueLength
 	if l, err := hdr.Length(); err != nil {
 		return nil, driver.WithStack(err)
 	} else if l < 3 {
 		return nil, driver.WithStack(fmt.Errorf("Expected a header of 3 elements, got %d", l))
+	} else {
+		hdrLen = l
 	}
 
 	resp := &vstResponse{
@@ -81,6 +89,16 @@ func newResponse(msg protocol.Message, endpoint string, rawResponse *[]byte) (*v
 	} else {
 		resp.ResponseCode = int(code)
 	}
+	// Decode meta
+	if hdrLen >= 4 {
+		if elem, err := hdr.At(3); err != nil {
+			return nil, driver.WithStack(err)
+		} else if !elem.IsObject() {
+			return nil, driver.WithStack(fmt.Errorf("Expected meta field to be of type Object, got %s", elem.Type()))
+		} else {
+			resp.meta = elem
+		}
+	}
 
 	// Fetch body directly after hdr
 	if body, err := hdr.Next(); err != nil {
@@ -130,6 +148,49 @@ func (r *vstResponse) CheckStatus(validStatusCodes ...int) error {
 	}
 }
 
+// Header returns the value of a response header with given key.
+// If no such header is found, an empty string is returned.
+func (r *vstResponse) Header(key string) string {
+	r.metaMutex.Lock()
+	defer r.metaMutex.Unlock()
+
+	if r.meta != nil {
+		if r.metaMap == nil {
+			// Read all headers
+			metaMap := make(map[string]string)
+			keyCount, err := r.meta.Length()
+			if err != nil {
+				return ""
+			}
+			for k := velocypack.ValueLength(0); k < keyCount; k++ {
+				key, err := r.meta.KeyAt(k)
+				if err != nil {
+					continue
+				}
+				value, err := r.meta.ValueAt(k)
+				if err != nil {
+					continue
+				}
+				keyStr, err := key.GetString()
+				if err != nil {
+					continue
+				}
+				valueStr, err := value.GetString()
+				if err != nil {
+					continue
+				}
+				metaMap[strings.ToLower(keyStr)] = valueStr
+			}
+			r.metaMap = metaMap
+		}
+		key = strings.ToLower(key)
+		if value, found := r.metaMap[key]; found {
+			return value
+		}
+	}
+	return ""
+}
+
 // ParseBody performs protocol specific unmarshalling of the response data into the given result.
 // If the given field is non-empty, the contents of that field will be parsed into the given result.
 func (r *vstResponse) ParseBody(field string, result interface{}) error {

vst/response_element.go

@@ -87,6 +87,12 @@ func (r *vstResponseElement) CheckStatus(validStatusCodes ...int) error {
 	}
 }
 
+// Header returns the value of a response header with given key.
+// If no such header is found, an empty string is returned.
+func (r *vstResponseElement) Header(key string) string {
+	return ""
+}
+
 // ParseBody performs protocol specific unmarshalling of the response data into the given result.
 // If the given field is non-empty, the contents of that field will be parsed into the given result.
 func (r *vstResponseElement) ParseBody(field string, result interface{}) error {