[issuegenerator] Refactor and divide into packages (#1237)

* [issuegenerator] Refactor and divide into packages

* Fix documentation

* Package:

* Formatting

* Add autogenerated label

Author: mx-psi

issuegenerator/internal/github/client.go

@@ -0,0 +1,307 @@
+// 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 github handles interaction with Github through the [Client].
+package github
+
+import (
+	"context"
+	"encoding"
+	"errors"
+	"fmt"
+	"io"
+	"net/http"
+	"os"
+	"strings"
+
+	"github.com/google/go-github/github"
+	"go.uber.org/zap"
+	"golang.org/x/oauth2"
+
+	"go.opentelemetry.io/build-tools/issuegenerator/internal/report"
+)
+
+const (
+	// Keys of required environment variables
+	githubOwnerAndRepository = "GITHUB_REPOSITORY"
+	githubWorkflow           = "GITHUB_ACTION"
+	githubAPITokenKey        = "GITHUB_TOKEN" // #nosec G101
+	githubSHAKey             = "GITHUB_SHA"
+	githubRefKey             = "GITHUB_REF"
+
+	githubOwner      = "githubOwner"
+	githubRepository = "githubRepository"
+
+	// Variables used to build workflow URL.
+	githubServerURL    = "GITHUB_SERVER_URL"
+	githubRunID        = "GITHUB_RUN_ID"
+	autoGeneratedLabel = "generated-by-issuegenerator"
+	issueTitleTemplate = `[${module}]: Report for failed tests on main`
+	issueBodyTemplate  = `
+Auto-generated report for ${jobName} job build.
+
+Link to failed build: ${linkToBuild}
+Commit: ${commit}
+PR: ${pr}
+
+### Component(s)
+${component}
+
+${failedTests}
+
+**Note**: Information about any subsequent build failures that happen while
+this issue is open, will be added as comments with more information to this issue.
+`
+	issueCommentTemplate = `
+Link to latest failed build: ${linkToBuild}
+Commit: ${commit}
+PR: ${pr}
+
+${failedTests}
+`
+)
+
+// CommaSeparatedList is a custom type for parsing comma-separated values.
+type CommaSeparatedList []string
+
+var _ encoding.TextMarshaler = (*CommaSeparatedList)(nil)
+
+// MarshalText is needed for flag.TextVar support.
+func (c CommaSeparatedList) MarshalText() ([]byte, error) {
+	return []byte(strings.Join(c, ",")), nil
+}
+
+var _ encoding.TextUnmarshaler = (*CommaSeparatedList)(nil)
+
+// UnmarshalText is needed for flag.TextVar support.
+func (c *CommaSeparatedList) UnmarshalText(text []byte) error {
+	for _, key := range strings.Split(string(text), ",") {
+		key = strings.TrimSpace(key)
+		if key == "" {
+			return errors.New("empty key in comma-separated list")
+		}
+		*c = append(*c, key)
+	}
+	return nil
+}
+
+// ClientConfig includes all the configuration to create a [Client].
+type ClientConfig struct {
+	Labels CommaSeparatedList
+}
+
+func (c *ClientConfig) labelsCopy() []string {
+	newSlice := make([]string, len(c.Labels))
+	copy(newSlice, c.Labels)
+	return newSlice
+}
+
+// Client for Github interaction
+type Client struct {
+	logger       *zap.Logger
+	client       *github.Client
+	envVariables map[string]string
+	cfg          ClientConfig
+}
+
+// NewClient creates a new client.
+func NewClient(ctx context.Context, logger *zap.Logger, cfg ClientConfig) (*Client, error) {
+	env, err := getRequiredEnv()
+	if err != nil {
+		return nil, err
+	}
+	ts := oauth2.StaticTokenSource(&oauth2.Token{AccessToken: env[githubAPITokenKey]})
+	tc := oauth2.NewClient(ctx, ts)
+	cfg.Labels = append(cfg.Labels, autoGeneratedLabel)
+	return &Client{
+		logger:       logger,
+		client:       github.NewClient(tc),
+		envVariables: env,
+		cfg:          cfg,
+	}, nil
+}
+
+// getRequiredEnv loads required environment variables for the main method.
+// Some of the environment variables are built-in in Github Actions, whereas others
+// need to be configured. See https://docs.github.com/en/actions/writing-workflows/choosing-what-your-workflow-does/store-information-in-variables#default-environment-variables
+// for a list of built-in environment variables.
+func getRequiredEnv() (map[string]string, error) {
+	env := map[string]string{}
+
+	// As shown in the docs, the GITHUB_REPOSITORY environment variable is of the form
+	// owner/repository.
+	// See https://docs.github.com/en/actions/writing-workflows/choosing-what-your-workflow-does/store-information-in-variables#default-environment-variables:~:text=or%20tag.-,GITHUB_REPOSITORY,-The%20owner%20and
+	ownerAndRepository := strings.Split(os.Getenv(githubOwnerAndRepository), "/")
+	env[githubOwner] = ownerAndRepository[0]
+	env[githubRepository] = ownerAndRepository[1]
+	env[githubWorkflow] = os.Getenv(githubWorkflow)
+	env[githubServerURL] = os.Getenv(githubServerURL)
+	env[githubRunID] = os.Getenv(githubRunID)
+	env[githubAPITokenKey] = os.Getenv(githubAPITokenKey)
+	env[githubSHAKey] = os.Getenv(githubSHAKey)
+	env[githubRefKey] = os.Getenv(githubRefKey)
+
+	for k, v := range env {
+		if v == "" {
+			return nil, fmt.Errorf("required environment variable %q not set", k)
+		}
+	}
+
+	return env, nil
+}
+
+// GetExistingIssue gathers an existing GitHub Issue related to previous failures
+// of the same module.
+func (c *Client) GetExistingIssue(ctx context.Context, module string) *github.Issue {
+
+	componentName := getComponent(trimModule(c.envVariables[githubOwner], c.envVariables[githubRepository], module))
+	issues, response, err := c.client.Issues.ListByRepo(
+		ctx,
+		c.envVariables[githubOwner],
+		c.envVariables[githubRepository],
+		&github.IssueListByRepoOptions{
+			State:  "open",
+			Labels: []string{autoGeneratedLabel, componentName},
+		},
+	)
+	if err != nil {
+		c.logger.Fatal("Failed to search GitHub Issues", zap.Error(err))
+	}
+
+	if response.StatusCode != http.StatusOK {
+		c.handleBadResponses(response)
+	}
+
+	if len(issues) > 0 {
+		if len(issues) > 1 {
+			issueLinks := make([]string, len(issues))
+			for i, issue := range issues {
+				if issue.HTMLURL != nil {
+					issueLinks[i] = *issue.HTMLURL
+				}
+				c.logger.Warn(
+					"Multiple existing Issues found for the same component",
+					zap.Strings("issue_links", issueLinks),
+				)
+			}
+		}
+		return issues[0]
+	}
+	return nil
+}
+
+// CommentOnIssue adds a new comment on an existing GitHub issue with
+// information about the latest failure. This method is expected to be
+// called only if there's an existing open Issue for the current job.
+func (c *Client) CommentOnIssue(ctx context.Context, r report.Report, issue *github.Issue) *github.IssueComment {
+	body := os.Expand(issueCommentTemplate, templateHelper(c.envVariables, r))
+
+	issueComment, response, err := c.client.Issues.CreateComment(
+		ctx,
+		c.envVariables[githubOwner],
+		c.envVariables[githubRepository],
+		*issue.Number,
+		&github.IssueComment{
+			Body: &body,
+		},
+	)
+	if err != nil {
+		c.logger.Fatal("Failed to search GitHub Issues", zap.Error(err))
+	}
+
+	if response.StatusCode != http.StatusCreated {
+		c.handleBadResponses(response)
+	}
+
+	return issueComment
+}
+
+func trimModule(owner, repo, module string) string {
+	return strings.TrimPrefix(module, fmt.Sprintf("github.com/%s/%s/", owner, repo))
+}
+
+func getComponent(module string) string {
+	parts := strings.Split(module, "/")
+	if len(parts) >= 2 {
+		return strings.Join(parts[:2], "/")
+	}
+	return module
+}
+
+func templateHelper(env map[string]string, r report.Report) func(string) string {
+	return func(param string) string {
+		switch param {
+		case "jobName":
+			return "`" + env[githubWorkflow] + "`"
+		case "linkToBuild":
+			return fmt.Sprintf("%s/%s/%s/actions/runs/%s", env[githubServerURL], env[githubOwner], env[githubRepository], env[githubRunID])
+		case "failedTests":
+			return r.FailedTestsMD()
+		case "component":
+			trimmedModule := trimModule(env[githubOwner], env[githubRepository], r.Module)
+			return getComponent(trimmedModule)
+		case "commit":
+			return env[githubSHAKey]
+		case "pr":
+			ref := env[githubRefKey]
+			parts := strings.Split(ref, "/")
+			if len(parts) == 4 && parts[1] == "pull" {
+				return "#" + parts[2]
+			}
+			return fmt.Sprintf("N/A (github_ref: %q)", ref)
+		default:
+			return ""
+		}
+	}
+}
+
+// CreateIssue creates a new GitHub Issue corresponding to a build failure.
+func (c *Client) CreateIssue(ctx context.Context, r report.Report) *github.Issue {
+	trimmedModule := trimModule(c.envVariables[githubOwner], c.envVariables[githubRepository], r.Module)
+	title := strings.Replace(issueTitleTemplate, "${module}", trimmedModule, 1)
+	body := os.Expand(issueBodyTemplate, templateHelper(c.envVariables, r))
+	componentName := getComponent(trimmedModule)
+
+	issueLabels := c.cfg.labelsCopy()
+	issueLabels = append(issueLabels, componentName)
+
+	issue, response, err := c.client.Issues.Create(
+		ctx,
+		c.envVariables[githubOwner],
+		c.envVariables[githubRepository],
+		&github.IssueRequest{
+			Title:  &title,
+			Body:   &body,
+			Labels: &issueLabels,
+		})
+	if err != nil {
+		c.logger.Fatal("Failed to create GitHub Issue", zap.Error(err))
+	}
+
+	if response.StatusCode != http.StatusCreated {
+		c.handleBadResponses(response)
+	}
+
+	return issue
+}
+
+func (c *Client) handleBadResponses(response *github.Response) {
+	body, _ := io.ReadAll(response.Body)
+	c.logger.Fatal(
+		"Unexpected response from GitHub",
+		zap.Int("status_code", response.StatusCode),
+		zap.String("response", string(body)),
+		zap.String("url", response.Request.URL.String()),
+	)
+}