From 3c22ec4fd8ef0efa29429674595c7b4269b33cea Mon Sep 17 00:00:00 2001 From: Ryan McGuire Date: Fri, 3 Jan 2025 17:13:15 -0500 Subject: [PATCH] Go HTTP Server with OTEL Template --- .gitignore | 2 ++ .vscode/launch.json | 16 ++++++++++ go.mod | 33 ++++++++++++++++++++ go.sum | 71 ++++++++++++++++++++++++++++++++++++++++++ main.go | 38 ++++++++++++++++++++++ pkg/config/config.go | 69 ++++++++++++++++++++++++++++++++++++++++ pkg/config/ctx.go | 28 +++++++++++++++++ pkg/logging/logging.go | 1 + 8 files changed, 258 insertions(+) create mode 100644 .vscode/launch.json create mode 100644 go.mod create mode 100644 go.sum create mode 100644 main.go create mode 100644 pkg/config/config.go create mode 100644 pkg/config/ctx.go create mode 100644 pkg/logging/logging.go diff --git a/.gitignore b/.gitignore index adf8f72..703a155 100644 --- a/.gitignore +++ b/.gitignore @@ -21,3 +21,5 @@ # Go workspace file go.work +# Environment +.env diff --git a/.vscode/launch.json b/.vscode/launch.json new file mode 100644 index 0000000..b79f986 --- /dev/null +++ b/.vscode/launch.json @@ -0,0 +1,16 @@ +{ + "$schema": "https://raw.githubusercontent.com/mfussenegger/dapconfig-schema/master/dapconfig-schema.json", + "version": "0.2.0", + "configurations": [ + { + "name": "Run Server", + "type": "delve", + "request": "launch", + "program": "${workspaceFolder}", + "env": { + "APP_NAME": "Go HTTP with OTEL" + }, + "args": [] + } + ] +} diff --git a/go.mod b/go.mod new file mode 100644 index 0000000..a31dc13 --- /dev/null +++ b/go.mod @@ -0,0 +1,33 @@ +module gitea.libretechconsulting.com/rmcguire/go-http-server-with-otel + +go 1.23.4 + +require ( + github.com/caarlos0/env/v9 v9.0.0 + github.com/rs/zerolog v1.33.0 + github.com/spf13/viper v1.19.0 + golang.org/x/sys v0.18.0 + gopkg.in/yaml.v3 v3.0.1 +) + +require ( + github.com/fsnotify/fsnotify v1.7.0 // indirect + github.com/hashicorp/hcl v1.0.0 // indirect + github.com/magiconair/properties v1.8.7 // indirect + github.com/mattn/go-colorable v0.1.13 // indirect + github.com/mattn/go-isatty v0.0.19 // indirect + github.com/mitchellh/mapstructure v1.5.0 // indirect + github.com/pelletier/go-toml/v2 v2.2.2 // indirect + github.com/sagikazarmark/locafero v0.4.0 // indirect + github.com/sagikazarmark/slog-shim v0.1.0 // indirect + github.com/sourcegraph/conc v0.3.0 // indirect + github.com/spf13/afero v1.11.0 // indirect + github.com/spf13/cast v1.6.0 // indirect + github.com/spf13/pflag v1.0.5 // indirect + github.com/subosito/gotenv v1.6.0 // indirect + go.uber.org/atomic v1.9.0 // indirect + go.uber.org/multierr v1.9.0 // indirect + golang.org/x/exp v0.0.0-20230905200255-921286631fa9 // indirect + golang.org/x/text v0.14.0 // indirect + gopkg.in/ini.v1 v1.67.0 // indirect +) diff --git a/go.sum b/go.sum new file mode 100644 index 0000000..8aa4ac3 --- /dev/null +++ b/go.sum @@ -0,0 +1,71 @@ +github.com/caarlos0/env/v9 v9.0.0 h1:SI6JNsOA+y5gj9njpgybykATIylrRMklbs5ch6wO6pc= +github.com/caarlos0/env/v9 v9.0.0/go.mod h1:ye5mlCVMYh6tZ+vCgrs/B95sj88cg5Tlnc0XIzgZ020= +github.com/coreos/go-systemd/v22 v22.5.0/go.mod h1:Y58oyj3AT4RCenI/lSvhwexgC+NSVTIJ3seZv2GcEnc= +github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38= +github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38= +github.com/fsnotify/fsnotify v1.7.0 h1:8JEhPFa5W2WU7YfeZzPNqzMP6Lwt7L2715Ggo0nosvA= +github.com/fsnotify/fsnotify v1.7.0/go.mod h1:40Bi/Hjc2AVfZrqy+aj+yEI+/bRxZnMJyTJwOpGvigM= +github.com/godbus/dbus/v5 v5.0.4/go.mod h1:xhWf0FNVPg57R7Z0UbKHbJfkEywrmjJnf7w5xrFpKfA= +github.com/hashicorp/hcl v1.0.0 h1:0Anlzjpi4vEasTeNFn2mLJgTSwt0+6sfsiTG8qcWGx4= +github.com/hashicorp/hcl v1.0.0/go.mod h1:E5yfLk+7swimpb2L/Alb/PJmXilQ/rhwaUYs4T20WEQ= +github.com/magiconair/properties v1.8.7 h1:IeQXZAiQcpL9mgcAe1Nu6cX9LLw6ExEHKjN0VQdvPDY= +github.com/magiconair/properties v1.8.7/go.mod h1:Dhd985XPs7jluiymwWYZ0G4Z61jb3vdS329zhj2hYo0= +github.com/mattn/go-colorable v0.1.13 h1:fFA4WZxdEF4tXPZVKMLwD8oUnCTTo08duU7wxecdEvA= +github.com/mattn/go-colorable v0.1.13/go.mod h1:7S9/ev0klgBDR4GtXTXX8a3vIGJpMovkB8vQcUbaXHg= +github.com/mattn/go-isatty v0.0.16/go.mod h1:kYGgaQfpe5nmfYZH+SKPsOc2e4SrIfOl2e/yFXSvRLM= +github.com/mattn/go-isatty v0.0.19 h1:JITubQf0MOLdlGRuRq+jtsDlekdYPia9ZFsB8h/APPA= +github.com/mattn/go-isatty v0.0.19/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y= +github.com/mitchellh/mapstructure v1.5.0 h1:jeMsZIYE/09sWLaz43PL7Gy6RuMjD2eJVyuac5Z2hdY= +github.com/mitchellh/mapstructure v1.5.0/go.mod h1:bFUtVrKA4DC2yAKiSyO/QUcy7e+RRV2QTWOzhPopBRo= +github.com/pelletier/go-toml/v2 v2.2.2 h1:aYUidT7k73Pcl9nb2gScu7NSrKCSHIDE89b3+6Wq+LM= +github.com/pelletier/go-toml/v2 v2.2.2/go.mod h1:1t835xjRzz80PqgE6HHgN2JOsmgYu/h4qDAS4n929Rs= +github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0= +github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4= +github.com/rs/xid v1.5.0/go.mod h1:trrq9SKmegXys3aeAKXMUTdJsYXVwGY3RLcfgqegfbg= +github.com/rs/zerolog v1.33.0 h1:1cU2KZkvPxNyfgEmhHAz/1A9Bz+llsdYzklWFzgp0r8= +github.com/rs/zerolog v1.33.0/go.mod h1:/7mN4D5sKwJLZQ2b/znpjC3/GQWY/xaDXUM0kKWRHss= +github.com/sagikazarmark/locafero v0.4.0 h1:HApY1R9zGo4DBgr7dqsTH/JJxLTTsOt7u6keLGt6kNQ= +github.com/sagikazarmark/locafero v0.4.0/go.mod h1:Pe1W6UlPYUk/+wc/6KFhbORCfqzgYEpgQ3O5fPuL3H4= +github.com/sagikazarmark/slog-shim v0.1.0 h1:diDBnUNK9N/354PgrxMywXnAwEr1QZcOr6gto+ugjYE= +github.com/sagikazarmark/slog-shim v0.1.0/go.mod h1:SrcSrq8aKtyuqEI1uvTDTK1arOWRIczQRv+GVI1AkeQ= +github.com/sourcegraph/conc v0.3.0 h1:OQTbbt6P72L20UqAkXXuLOj79LfEanQ+YQFNpLA9ySo= +github.com/sourcegraph/conc v0.3.0/go.mod h1:Sdozi7LEKbFPqYX2/J+iBAM6HpqSLTASQIKqDmF7Mt0= +github.com/spf13/afero v1.11.0 h1:WJQKhtpdm3v2IzqG8VMqrr6Rf3UYpEF239Jy9wNepM8= +github.com/spf13/afero v1.11.0/go.mod h1:GH9Y3pIexgf1MTIWtNGyogA5MwRIDXGUr+hbWNoBjkY= +github.com/spf13/cast v1.6.0 h1:GEiTHELF+vaR5dhz3VqZfFSzZjYbgeKDpBxQVS4GYJ0= +github.com/spf13/cast v1.6.0/go.mod h1:ancEpBxwJDODSW/UG4rDrAqiKolqNNh2DX3mk86cAdo= +github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA= +github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg= +github.com/spf13/viper v1.19.0 h1:RWq5SEjt8o25SROyN3z2OrDB9l7RPd3lwTWU8EcEdcI= +github.com/spf13/viper v1.19.0/go.mod h1:GQUN9bilAbhU/jgc1bKs99f/suXKeUMct8Adx5+Ntkg= +github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME= +github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw= +github.com/stretchr/objx v0.5.0/go.mod h1:Yh+to48EsGEfYuaHDzXPcE3xhTkx73EhmCGUpEOglKo= +github.com/stretchr/objx v0.5.2/go.mod h1:FRsXN1f5AsAjCGJKqEizvkpNtU+EGNCLh3NxZ/8L+MA= +github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI= +github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg= +github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU= +github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo= +github.com/stretchr/testify v1.9.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY= +github.com/subosito/gotenv v1.6.0 h1:9NlTDc1FTs4qu0DDq7AEtTPNw6SVm7uBMsUCUjABIf8= +github.com/subosito/gotenv v1.6.0/go.mod h1:Dk4QP5c2W3ibzajGcXpNraDfq2IrhjMIvMSWPKKo0FU= +go.uber.org/atomic v1.9.0 h1:ECmE8Bn/WFTYwEW/bpKD3M8VtR/zQVbavAoalC1PYyE= +go.uber.org/atomic v1.9.0/go.mod h1:fEN4uk6kAWBTFdckzkM89CLk9XfWZrxpCo0nPH17wJc= +go.uber.org/multierr v1.9.0 h1:7fIwc/ZtS0q++VgcfqFDxSBZVv/Xo49/SYnDFupUwlI= +go.uber.org/multierr v1.9.0/go.mod h1:X2jQV1h+kxSjClGpnseKVIxpmcjrj7MNnI0bnlfKTVQ= +golang.org/x/exp v0.0.0-20230905200255-921286631fa9 h1:GoHiUyI/Tp2nVkLI2mCxVkOjsbSXD66ic0XW0js0R9g= +golang.org/x/exp v0.0.0-20230905200255-921286631fa9/go.mod h1:S2oDrQGGwySpoQPVqRShND87VCbxmc6bL1Yd2oYrm6k= +golang.org/x/sys v0.0.0-20220811171246-fbc7d0a398ab/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg= +golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg= +golang.org/x/sys v0.12.0 h1:CM0HF96J0hcLAwsHPJZjfdNzs0gftsLfgKt57wWHJ0o= +golang.org/x/sys v0.12.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg= +golang.org/x/sys v0.18.0 h1:DBdB3niSjOA/O0blCZBqDefyWNYveAYMNF1Wum0DYQ4= +golang.org/x/sys v0.18.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA= +golang.org/x/text v0.14.0 h1:ScX5w1eTa3QqT8oi6+ziP7dTV1S2+ALU0bI+0zXKWiQ= +golang.org/x/text v0.14.0/go.mod h1:18ZOQIKpY8NJVqYksKHtTdi31H5itFRjB5/qKTNYzSU= +gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0= +gopkg.in/ini.v1 v1.67.0 h1:Dgnx+6+nfE+IfzjUEISNeydPJh9AXNNsWbGP9KzCsOA= +gopkg.in/ini.v1 v1.67.0/go.mod h1:pNLf8WUiyNEtQjuu5G5vTm06TEv9tsIgeAvK8hOrP4k= +gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM= +gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA= +gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM= diff --git a/main.go b/main.go new file mode 100644 index 0000000..9a16fc0 --- /dev/null +++ b/main.go @@ -0,0 +1,38 @@ +// This template contains a simple +// app with OTEL bootstrap that will create an +// HTTP server configured by environment that exports +// spans and metrics to an OTEL collector if configured +// to do so. Will also stand up a prometheus metrics +// endpoint. +package main + +import ( + "context" + "fmt" + "os" + "os/signal" + + "golang.org/x/sys/unix" + + "gitea.libretechconsulting.com/rmcguire/go-http-server-with-otel/pkg/config" +) + +func main() { + ctx, cncl := signal.NotifyContext(context.Background(), os.Interrupt, unix.SIGTERM) + defer cncl() + + conf, err := config.LoadConfig() + if err != nil { + panic(err) + } + ctx = conf.AddToCtx(ctx) + + conf, err = config.FromCtx(ctx) + if err != nil { + panic(err) + } + + fmt.Printf("%#v\n", conf) +} + +func init() {} diff --git a/pkg/config/config.go b/pkg/config/config.go new file mode 100644 index 0000000..492695d --- /dev/null +++ b/pkg/config/config.go @@ -0,0 +1,69 @@ +package config + +import ( + "flag" + "fmt" + "os" + + "github.com/caarlos0/env/v9" + "gopkg.in/yaml.v3" +) + +type AppConfig struct { + Name string `yaml:"name" env:"APP_NAME" envDefault:"go-http-server-with-otel"` + Environment string `yaml:"environment" env:"APP_ENVIRONMENT" envDefault:"development"` + Version string `yaml:"version" env:"APP_VERSION"` + Logging LogConfig `yaml:"logging"` + HTTP HTTPConfig `yaml:"http"` + OTEL OTELConfig `yaml:"otel"` +} + +type LogConfig struct { + Enabled bool `yaml:"enabled" env:"APP_LOGGING_ENABLED" envDefault:"true"` + Level string `yaml:"level" env:"APP_LOGGING_LEVEL" envDefault:"info"` + Format string `yaml:"format" env:"APP_LOGGING_FORMAT" envDefault:"json"` +} + +type HTTPConfig struct { + Listen string `yaml:"listen" env:"APP_HTTP_LISTEN" envDefault:"127.0.0.1:8080"` + RequestTimeout int `yaml:"request_timeout" env:"APP_HTTP_REQUEST_TIMEOUT" envDefault:"30"` +} + +type OTELConfig struct { + Enabled bool `yaml:"enabled" env:"APP_OTEL_ENABLED" envDefault:"true"` + PrometheusEnabled bool `yaml:"prometheus_enabled" env:"APP_OTEL_PROMETHEUS_ENABLED" envDefault:"true"` + PrometheusPath string `yaml:"prometheus_path" env:"APP_OTEL_PROMETHEUS_PATH" envDefault:"/metrics"` +} + +// Calling this will try to load from config if -config is +// provided, otherwise will return *AppConfig with defaults, +// performing any environment substitutions +func LoadConfig() (*AppConfig, error) { + configPath := flag.String("config", "", "Path to the configuration file") + flag.Parse() + + return loadConfig(*configPath) +} + +func loadConfig(configPath string) (*AppConfig, error) { + cfg := AppConfig{} + + if configPath != "" { + file, err := os.Open(configPath) + if err != nil { + return nil, fmt.Errorf("could not open config file: %w", err) + } + defer file.Close() + + decoder := yaml.NewDecoder(file) + if err := decoder.Decode(&cfg); err != nil { + return nil, fmt.Errorf("could not decode config file: %w", err) + } + } + + if err := env.Parse(&cfg); err != nil { + return nil, fmt.Errorf("could not parse environment variables: %w", err) + } + + return &cfg, nil +} diff --git a/pkg/config/ctx.go b/pkg/config/ctx.go new file mode 100644 index 0000000..b5dc76c --- /dev/null +++ b/pkg/config/ctx.go @@ -0,0 +1,28 @@ +package config + +import ( + "context" + "errors" +) + +type appConfigKey uint8 + +const appConfigCtxKey appConfigKey = iota + +func (a *AppConfig) AddToCtx(ctx context.Context) context.Context { + return context.WithValue(ctx, appConfigCtxKey, a) +} + +func FromCtx(ctx context.Context) (*AppConfig, error) { + ctxData := ctx.Value(appConfigCtxKey) + if ctxData == nil { + return nil, errors.New("no config found in context") + } + + cfg, ok := ctxData.(*AppConfig) + if !ok { + return nil, errors.New("invalid config stored in context") + } + + return cfg, nil +} diff --git a/pkg/logging/logging.go b/pkg/logging/logging.go new file mode 100644 index 0000000..2b43acc --- /dev/null +++ b/pkg/logging/logging.go @@ -0,0 +1 @@ +package logging