contrib/google.golang.org/api: add google api integration

contrib/google.golang.org/api/api.go

@@ -0,0 +1,50 @@
+// Package api provides functions to trace the google.golang.org/api package.
+package api // import "gopkg.in/DataDog/dd-trace-go.v1/contrib/google.golang.org/api"
+
+//go:generate go run make_endpoints.go
+
+import (
+	"net/http"
+
+	"golang.org/x/oauth2/google"
+	"gopkg.in/DataDog/dd-trace-go.v1/contrib/google.golang.org/api/internal"
+	httptrace "gopkg.in/DataDog/dd-trace-go.v1/contrib/net/http"
+	"gopkg.in/DataDog/dd-trace-go.v1/ddtrace"
+	"gopkg.in/DataDog/dd-trace-go.v1/ddtrace/ext"
+)
+
+// apiEndpoints are all of the defined endpoints for the Google API; it is populated
+// by "go generate".
+var apiEndpoints *internal.Tree
+
+// NewClient creates a new oauth http client suitable for use with the google
+// APIs with all requests traced automatically.
+func NewClient(options ...Option) (*http.Client, error) {
+	cfg := newConfig(options...)
+	client, err := google.DefaultClient(cfg.ctx, cfg.scopes...)
+	if err != nil {
+		return nil, err
+	}
+	client.Transport = WrapRoundTripper(client.Transport, options...)
+	return client, nil
+}
+
+// WrapRoundTripper wraps a RoundTripper intended for interfacing with
+// Google APIs and traces all requests.
+func WrapRoundTripper(transport http.RoundTripper, options ...Option) http.RoundTripper {
+	cfg := newConfig(options...)
+	return httptrace.WrapRoundTripper(transport,
+		httptrace.WithBefore(func(req *http.Request, span ddtrace.Span) {
+			e, ok := apiEndpoints.Get(req.URL.Hostname(), req.Method, req.URL.Path)
+			if ok {
+				span.SetTag(ext.ServiceName, e.ServiceName)
+				span.SetTag(ext.ResourceName, e.ResourceName)
+			} else {
+				span.SetTag(ext.ServiceName, "google")
+				span.SetTag(ext.ResourceName, req.Method+" "+req.URL.Hostname())
+			}
+			if cfg.serviceName != "" {
+				span.SetTag(ext.ServiceName, cfg.serviceName)
+			}
+		}))
+}

contrib/google.golang.org/api/api_test.go

@@ -0,0 +1,106 @@
+package api
+
+import (
+	"io/ioutil"
+	"net/http"
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	books "google.golang.org/api/books/v1"
+	civicinfo "google.golang.org/api/civicinfo/v2"
+	urlshortener "google.golang.org/api/urlshortener/v1"
+	"gopkg.in/DataDog/dd-trace-go.v1/ddtrace/ext"
+	"gopkg.in/DataDog/dd-trace-go.v1/ddtrace/mocktracer"
+)
+
+type roundTripperFunc func(*http.Request) (*http.Response, error)
+
+func (f roundTripperFunc) RoundTrip(req *http.Request) (*http.Response, error) {
+	return f(req)
+}
+
+var badRequestTransport roundTripperFunc = func(req *http.Request) (*http.Response, error) {
+	res := &http.Response{
+		Header:     make(http.Header),
+		Request:    req,
+		StatusCode: http.StatusBadRequest,
+		Body:       ioutil.NopCloser(strings.NewReader("")),
+	}
+	return res, nil
+}
+
+func TestBooks(t *testing.T) {
+	mt := mocktracer.Start()
+	defer mt.Stop()
+
+	svc, err := books.New(&http.Client{
+		Transport: WrapRoundTripper(badRequestTransport),
+	})
+	assert.NoError(t, err)
+	svc.Bookshelves.
+		List("montana.banana").
+		Do()
+
+	spans := mt.FinishedSpans()
+	assert.Len(t, spans, 1)
+
+	s0 := spans[0]
+	assert.Equal(t, "http.request", s0.OperationName())
+	assert.Equal(t, "http", s0.Tag(ext.SpanType))
+	assert.Equal(t, "google.books", s0.Tag(ext.ServiceName))
+	assert.Equal(t, "books.bookshelves.list", s0.Tag(ext.ResourceName))
+	assert.Equal(t, "400", s0.Tag(ext.HTTPCode))
+	assert.Equal(t, "GET", s0.Tag(ext.HTTPMethod))
+	assert.Equal(t, "/books/v1/users/montana.banana/bookshelves", s0.Tag(ext.HTTPURL))
+}
+
+func TestCivicInfo(t *testing.T) {
+	mt := mocktracer.Start()
+	defer mt.Stop()
+
+	svc, err := civicinfo.New(&http.Client{
+		Transport: WrapRoundTripper(badRequestTransport),
+	})
+	assert.NoError(t, err)
+	svc.Representatives.
+		RepresentativeInfoByAddress(&civicinfo.RepresentativeInfoRequest{}).
+		Do()
+
+	spans := mt.FinishedSpans()
+	assert.Len(t, spans, 1)
+
+	s0 := spans[0]
+	assert.Equal(t, "http.request", s0.OperationName())
+	assert.Equal(t, "http", s0.Tag(ext.SpanType))
+	assert.Equal(t, "google.civicinfo", s0.Tag(ext.ServiceName))
+	assert.Equal(t, "civicinfo.representatives.representativeInfoByAddress", s0.Tag(ext.ResourceName))
+	assert.Equal(t, "400", s0.Tag(ext.HTTPCode))
+	assert.Equal(t, "GET", s0.Tag(ext.HTTPMethod))
+	assert.Equal(t, "/civicinfo/v2/representatives", s0.Tag(ext.HTTPURL))
+}
+
+func TestURLShortener(t *testing.T) {
+	mt := mocktracer.Start()
+	defer mt.Stop()
+
+	svc, err := urlshortener.New(&http.Client{
+		Transport: WrapRoundTripper(badRequestTransport),
+	})
+	assert.NoError(t, err)
+	svc.Url.
+		List().
+		Do()
+
+	spans := mt.FinishedSpans()
+	assert.Len(t, spans, 1)
+
+	s0 := spans[0]
+	assert.Equal(t, "http.request", s0.OperationName())
+	assert.Equal(t, "http", s0.Tag(ext.SpanType))
+	assert.Equal(t, "google.urlshortener", s0.Tag(ext.ServiceName))
+	assert.Equal(t, "urlshortener.url.list", s0.Tag(ext.ResourceName))
+	assert.Equal(t, "400", s0.Tag(ext.HTTPCode))
+	assert.Equal(t, "GET", s0.Tag(ext.HTTPMethod))
+	assert.Equal(t, "/urlshortener/v1/url/history", s0.Tag(ext.HTTPURL))
+}