github.com/cornelk/go-cloud@v0.17.1/server/sdserver/server.go (about)

     1  // Copyright 2018 The Go Cloud Development Kit Authors
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     https://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  // Package sdserver provides the diagnostic hooks for a server using
    16  // Stackdriver.
    17  package sdserver // import "github.com/cornelk/go-cloud/server/sdserver"
    18  
    19  import (
    20  	"fmt"
    21  	"os"
    22  
    23  	"github.com/cornelk/go-cloud/gcp"
    24  	"github.com/cornelk/go-cloud/internal/useragent"
    25  	"github.com/cornelk/go-cloud/server"
    26  	"github.com/cornelk/go-cloud/server/requestlog"
    27  	"github.com/google/wire"
    28  
    29  	"contrib.go.opencensus.io/exporter/stackdriver"
    30  	"contrib.go.opencensus.io/exporter/stackdriver/monitoredresource"
    31  	"go.opencensus.io/trace"
    32  	"golang.org/x/oauth2"
    33  	"google.golang.org/api/option"
    34  )
    35  
    36  // Set is a Wire provider set that provides the diagnostic hooks for
    37  // *server.Server given a GCP token source and a GCP project ID.
    38  var Set = wire.NewSet(
    39  	server.Set,
    40  	NewExporter,
    41  	monitoredresource.Autodetect,
    42  	wire.Bind(new(trace.Exporter), new(*stackdriver.Exporter)),
    43  	NewRequestLogger,
    44  	wire.Bind(new(requestlog.Logger), new(*requestlog.StackdriverLogger)),
    45  )
    46  
    47  // NewExporter returns a new OpenCensus Stackdriver exporter.
    48  //
    49  // The second return value is a Wire cleanup function that calls Flush
    50  // on the exporter.
    51  func NewExporter(id gcp.ProjectID, ts gcp.TokenSource, mr monitoredresource.Interface) (*stackdriver.Exporter, func(), error) {
    52  	opts := []option.ClientOption{
    53  		option.WithTokenSource(oauth2.TokenSource(ts)),
    54  		useragent.ClientOption("server"),
    55  	}
    56  	exp, err := stackdriver.NewExporter(stackdriver.Options{
    57  		ProjectID:               string(id),
    58  		MonitoringClientOptions: opts,
    59  		TraceClientOptions:      opts,
    60  		MonitoredResource:       mr,
    61  	})
    62  	if err != nil {
    63  		return nil, nil, err
    64  	}
    65  
    66  	return exp, func() { exp.Flush() }, err
    67  }
    68  
    69  // NewRequestLogger returns a request logger that sends entries to stdout.
    70  func NewRequestLogger() *requestlog.StackdriverLogger {
    71  	// For now, request logs are written to stdout and get picked up by fluentd.
    72  	// This also works when running locally.
    73  	return requestlog.NewStackdriverLogger(os.Stdout, func(e error) { fmt.Println(e) })
    74  }