Semantic Convention generation tooling

.github/dependabot.yml

@@ -216,3 +216,13 @@ updates:
     schedule:
       day: sunday
       interval: weekly
+  -
+    package-ecosystem: gomod
+    directory: /internal/tools/semconv-gen
+    labels:
+      - dependencies
+      - go
+      - "Skip Changelog"
+    schedule:
+      day: sunday
+      interval: weekly

CHANGELOG.md

@@ -40,6 +40,7 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 - The `ExportSpans` method of the`SpanExporter` interface type was updated to accept `ReadOnlySpan`s instead of the removed `SpanSnapshot`.
   This brings the export interface into compliance with the specification in that it now accepts an explicitly immutable type instead of just an implied one. (#1873)
 - Unembed `SpanContext` in `Link`. (#1877)
+- Semantic conventions are now generated from the specification YAML. (#1891)
 
 ### Deprecated
 

Makefile

@@ -40,6 +40,9 @@ $(TOOLS)/%: | $(TOOLS)
 	cd $(TOOLS_MOD_DIR) && \
 	$(GO) build -o $@ $(PACKAGE)
 
+SEMCONVGEN = $(TOOLS)/semconv-gen
+$(TOOLS)/semconv-gen: PACKAGE=go.opentelemetry.io/otel/$(TOOLS_MOD_DIR)/semconv-gen
+
 CROSSLINK = $(TOOLS)/crosslink
 $(TOOLS)/crosslink: PACKAGE=go.opentelemetry.io/otel/$(TOOLS_MOD_DIR)/crosslink
 
@@ -55,7 +58,7 @@ $(TOOLS)/stringer: PACKAGE=golang.org/x/tools/cmd/stringer
 $(TOOLS)/gojq: PACKAGE=github.com/itchyny/gojq/cmd/gojq
 
 .PHONY: tools
-tools: $(CROSSLINK) $(GOLANGCI_LINT) $(MISSPELL) $(STRINGER) $(TOOLS)/gojq
+tools: $(CROSSLINK) $(GOLANGCI_LINT) $(MISSPELL) $(STRINGER) $(TOOLS)/gojq $(SEMCONVGEN)
 
 
 # Build

internal/tools/go.mod

@@ -7,6 +7,7 @@ require (
 	github.com/gogo/protobuf v1.3.2
 	github.com/golangci/golangci-lint v1.39.0
 	github.com/itchyny/gojq v0.12.3
+	github.com/spf13/pflag v1.0.5
 	golang.org/x/tools v0.1.0
 )
 

internal/tools/semconv-gen/generator.go

@@ -0,0 +1,319 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package main
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path"
+	"path/filepath"
+	"regexp"
+	"strings"
+
+	flag "github.com/spf13/pflag"
+)
+
+func main() {
+	cfg := config{}
+	flag.StringVarP(&cfg.inputPath, "input", "i", "", "Path to semantic convention definition YAML")
+	flag.StringVarP(&cfg.outputPath, "output", "o", "semconv", "Path to output target. Must be either an absolute path or relative to the repository root.")
+	flag.StringVarP(&cfg.containerImage, "container", "c", "otel/semconvgen", "Container image ID")
+	flag.StringVarP(&cfg.outputFilename, "filename", "f", "", "Filename for templated output. If not specified 'basename(inputPath).go' will be used.")
+	flag.StringVarP(&cfg.templateFilename, "template", "t", "template.j2", "Template filename")
+	flag.Parse()
+
+	cfg, err := validateConfig(cfg)
+	if err != nil {
+		fmt.Println(err)
+		flag.Usage()
+		os.Exit(-1)
+	}
+
+	err = render(cfg)
+	if err != nil {
+		panic(err)
+	}
+
+	err = fixIdentifiers(cfg.outputFilename)
+	if err != nil {
+		panic(err)
+	}
+
+	err = format(cfg.outputFilename)
+	if err != nil {
+		panic(err)
+	}
+}
+
+type config struct {
+	inputPath        string
+	outputPath       string
+	outputFilename   string
+	templateFilename string
+	containerImage   string
+}
+
+func validateConfig(cfg config) (config, error) {
+	if cfg.inputPath == "" {
+		return config{}, errors.New("input path must be provided")
+	}
+
+	if cfg.outputFilename == "" {
+		cfg.outputFilename = fmt.Sprintf("%s.go", path.Base(cfg.inputPath))
+	}
+
+	if !path.IsAbs(cfg.outputPath) {
+		root, err := findRepoRoot()
+		if err != nil {
+			return config{}, err
+		}
+		cfg.outputPath = path.Join(root, cfg.outputPath)
+	}
+
+	cfg.outputFilename = path.Join(cfg.outputPath, cfg.outputFilename)
+
+	if !path.IsAbs(cfg.templateFilename) {
+		pwd, err := os.Getwd()
+		if err != nil {
+			return config{}, err
+		}
+		cfg.templateFilename = path.Join(pwd, cfg.templateFilename)
+	}
+
+	return cfg, nil
+}
+
+func render(cfg config) error {
+	tmpDir, err := os.MkdirTemp("", "otel_semconvgen")
+	if err != nil {
+		return fmt.Errorf("unable to create temporary directory: %w", err)
+	}
+	defer os.RemoveAll(tmpDir)
+
+	inputPath := path.Join(tmpDir, "input")
+	err = os.Mkdir(inputPath, 0700)
+	if err != nil {
+		return fmt.Errorf("unable to create input directory: %w", err)
+	}
+
+	outputPath := path.Join(tmpDir, "output")
+	err = os.Mkdir(outputPath, 0700)
+	if err != nil {
+		return fmt.Errorf("unable to create output directory: %w", err)
+	}
+
+	err = exec.Command("cp", "-a", cfg.inputPath, inputPath).Run()
+	if err != nil {
+		return fmt.Errorf("unable to copy input to temp directory: %w", err)
+	}
+
+	err = exec.Command("cp", cfg.templateFilename, tmpDir).Run()
+	if err != nil {
+		return fmt.Errorf("unable to copy template to temp directory: %w", err)
+	}
+
+	cmd := exec.Command("docker", "run", "--rm",
+		"-v", fmt.Sprintf("%s:/data", tmpDir),
+		cfg.containerImage,
+		"--yaml-root", path.Join("/data/input", path.Base(cfg.inputPath)),
+		"code",
+		"--template", path.Join("/data", path.Base(cfg.templateFilename)),
+		"--output", path.Join("/data/output", path.Base(cfg.outputFilename)),
+	)
+	err = cmd.Run()
+	if err != nil {
+		return fmt.Errorf("unable to render template: %w", err)
+	}
+
+	err = exec.Command("cp", path.Join(tmpDir, "output", path.Base(cfg.outputFilename)), cfg.outputPath).Run()
+	if err != nil {
+		return fmt.Errorf("unable to copy result to target: %w", err)
+	}
+
+	return nil
+}
+
+func findRepoRoot() (string, error) {
+	start, err := os.Getwd()
+	if err != nil {
+		return "", err
+	}
+
+	dir := start
+	for {
+		_, err := os.Stat(filepath.Join(dir, ".git"))
+		if errors.Is(err, os.ErrNotExist) {
+			dir = filepath.Dir(dir)
+			// From https://golang.org/pkg/path/filepath/#Dir:
+			// The returned path does not end in a separator unless it is the root directory.
+			if strings.HasSuffix(dir, string(filepath.Separator)) {
+				return "", fmt.Errorf("unable to find git repository enclosing working dir %s", start)
+			}
+			continue
+		}
+
+		if err != nil {
+			return "", err
+		}
+
+		return dir, nil
+	}
+}
+
+var capitalizations = []string{
+	"ACL",
+	"AIX",
+	"AKS",
+	"AMD64",
+	"API",
+	"ARM32",
+	"ARM64",
+	"ARN",
+	"ARNs",
+	"ASCII",
+	"AWS",
+	"CPU",
+	"CSS",
+	"DB",
+	"DC",
+	"DNS",
+	"EC2",
+	"ECS",
+	"EDB",
+	"EKS",
+	"EOF",
+	"GCP",
+	"GRPC",
+	"GUID",
+	"HPUX",
+	"HSQLDB",
+	"HTML",
+	"HTTP",
+	"HTTPS",
+	"IA64",
+	"ID",
+	"IP",
+	"JDBC",
+	"JSON",
+	"K8S",
+	"LHS",
+	"MSSQL",
+	"OS",
+	"PHP",
+	"PID",
+	"PPC32",
+	"PPC64",
+	"QPS",
+	"QUIC",
+	"RAM",
+	"RHS",
+	"RPC",
+	"SDK",
+	"SLA",
+	"SMTP",
+	"SPDY",
+	"SQL",
+	"SSH",
+	"TCP",
+	"TLS",
+	"TTL",
+	"UDP",
+	"UID",
+	"UI",
+	"UUID",
+	"URI",
+	"URL",
+	"UTF8",
+	"VM",
+	"XML",
+	"XMPP",
+	"XSRF",
+	"XSS",
+	"ZOS",
+	"CronJob",
+	"WebEngine",
+	"MySQL",
+	"PostgreSQL",
+	"MariaDB",
+	"MaxDB",
+	"FirstSQL",
+	"InstantDB",
+	"HBase",
+	"MongoDB",
+	"CouchDB",
+	"CosmosDB",
+	"DynamoDB",
+	"HanaDB",
+	"FreeBSD",
+	"NetBSD",
+	"OpenBSD",
+	"DragonflyBSD",
+	"InProc",
+	"FaaS",
+}
+
+// These are not simple capitalization fixes, but require string replacement.
+// All occurrences of the key will be replaced with the corresponding value.
+var replacements = map[string]string{
+	"RedisDatabase": "RedisDB",
+	"IPTCP":         "TCP",
+	"IPUDP":         "UDP",
+	"Lineno":        "LineNumber",
+}
+
+func fixIdentifiers(fn string) error {
+	data, err := ioutil.ReadFile(fn)
+	if err != nil {
+		return fmt.Errorf("unable to read file: %w", err)
+	}
+
+	for _, init := range capitalizations {
+		// Match the title-cased capitalization target, asserting that its followed by
+		// either a capital letter, whitespace, a digit, or the end of text.
+		// This is to avoid, e.g., turning "Identifier" into "IDentifier".
+		re := regexp.MustCompile(strings.Title(strings.ToLower(init)) + `([A-Z\s\d]|$)`)
+		// RE2 does not support zero-width lookahead assertions, so we have to replace
+		// the last character that may have matched the first capture group in the
+		// expression constructed above.
+		data = re.ReplaceAll(data, []byte(init+`$1`))
+	}
+
+	for cur, repl := range replacements {
+		data = bytes.ReplaceAll(data, []byte(cur), []byte(repl))
+	}
+
+	err = ioutil.WriteFile(fn, data, 0644)
+	if err != nil {
+		return fmt.Errorf("unable to write updated file: %w", err)
+	}
+
+	return nil
+}
+
+func format(fn string) error {
+	cmd := exec.Command("gofmt", "-w", "-s", fn)
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	err := cmd.Run()
+	if err != nil {
+		return fmt.Errorf("unable to format updated file: %w", err)
+	}
+
+	return nil
+}