From b5a5582a2318ea9971d0972116f6379a41bf7d91 Mon Sep 17 00:00:00 2001
From: Cody Oss <6331106+codyoss@users.noreply.github.com>
Date: Tue, 25 Aug 2020 12:44:43 -0600
Subject: [PATCH] chore(internal/gapicgen): have genbot fallback to env vars
 (#2762)

Moved all direct use of env vars out of docker and into the Go
code.
---
 internal/gapicgen/cmd/genbot/Dockerfile |  5 -----
 internal/gapicgen/cmd/genbot/README.md  | 15 ++++++---------
 internal/gapicgen/cmd/genbot/github.go  | 15 +++++++++++++--
 internal/gapicgen/cmd/genbot/main.go    | 12 ++++++++++++
 4 files changed, 31 insertions(+), 16 deletions(-)

diff --git a/internal/gapicgen/cmd/genbot/Dockerfile b/internal/gapicgen/cmd/genbot/Dockerfile
index 6b5353e3887b..f016c213ad93 100644
--- a/internal/gapicgen/cmd/genbot/Dockerfile
+++ b/internal/gapicgen/cmd/genbot/Dockerfile
@@ -41,13 +41,8 @@ RUN mkdir /root/.ssh && echo -e "Host github.com\n\tStrictHostKeyChecking no\n"
 
 RUN echo -e '#!/bin/bash\n\
     set -ex\n\
-    echo "https://$GITHUB_USERNAME:$GITHUB_ACCESS_TOKEN@github.com" > ~/.git-credentials \n\
     go mod download \n\
     go run cloud.google.com/go/internal/gapicgen/cmd/genbot \
-    --githubAccessToken=$GITHUB_ACCESS_TOKEN \
-    --githubUsername=$GITHUB_USERNAME \
-    --githubName="$GITHUB_NAME" \
-    --githubEmail=$GITHUB_EMAIL \
     ' >> /run.sh
 RUN chmod a+x /run.sh
 
diff --git a/internal/gapicgen/cmd/genbot/README.md b/internal/gapicgen/cmd/genbot/README.md
index 0365e26bcc4e..1fa64ea63bfc 100644
--- a/internal/gapicgen/cmd/genbot/README.md
+++ b/internal/gapicgen/cmd/genbot/README.md
@@ -18,10 +18,7 @@ non-trivial amounts of space on your computer.
 1. Make sure you have all the tools installed listed in genlocal's README.md
 2. Run:
 
-```
-export GITHUB_USERNAME=jadekler
-export GITHUB_ACCESS_TOKEN=11223344556677889900aabbccddeeff11223344
-echo "https://$GITHUB_USERNAME:$GITHUB_ACCESS_TOKEN@github.com" > ~/.git-credentials
+```shell
 cd /path/to/internal/gapicgen
 go run cloud.google.com/go/internal/gapicgen/cmd/genbot \
     --githubAccessToken=$GITHUB_ACCESS_TOKEN \
@@ -37,15 +34,15 @@ Note: this can be quite slow (~10m).
 Note: this may leave a lot of docker resources laying around. Use
 `docker system prune` to clean up after runs.
 
-```
+```shell
 cd /path/to/internal/gapicgen/cmd/genbot
 docker build . -t genbot
 docker run -t --rm --privileged \
     -v `pwd`/../..:/gapicgen \
-    -e "GITHUB_ACCESS_TOKEN=11223344556677889900aabbccddeeff11223344" \
-    -e "GITHUB_USERNAME=jadekler" \
-    -e "GITHUB_NAME=\"Jean de Klerk\"" \
-    -e "GITHUB_EMAIL=deklerk@google.com" \
+    -e GITHUB_ACCESS_TOKEN \
+    -e GITHUB_USERNAME \
+    -e GITHUB_NAME \
+    -e GITHUB_EMAIL \
     genbot
 ```
 
diff --git a/internal/gapicgen/cmd/genbot/github.go b/internal/gapicgen/cmd/genbot/github.go
index 8be0eae8854c..1c944716216e 100644
--- a/internal/gapicgen/cmd/genbot/github.go
+++ b/internal/gapicgen/cmd/genbot/github.go
@@ -17,9 +17,12 @@ package main
 import (
 	"context"
 	"fmt"
+	"io/ioutil"
 	"log"
 	"os"
 	"os/exec"
+	"os/user"
+	"path"
 	"strings"
 	"time"
 
@@ -91,7 +94,7 @@ type GithubClient struct {
 
 // NewGithubClient creates a new GithubClient.
 func NewGithubClient(ctx context.Context, username, name, email, accessToken string) (*GithubClient, error) {
-	if err := setGitCreds(name, email); err != nil {
+	if err := setGitCreds(name, email, username, accessToken); err != nil {
 		return nil, err
 	}
 
@@ -103,7 +106,15 @@ func NewGithubClient(ctx context.Context, username, name, email, accessToken str
 }
 
 // SetGitCreds sets credentials for gerrit.
-func setGitCreds(githubName, githubEmail string) error {
+func setGitCreds(githubName, githubEmail, githubUsername, accessToken string) error {
+	u, err := user.Current()
+	if err != nil {
+		return err
+	}
+	gitCredentials := []byte(fmt.Sprintf("https://%s:%s@github.com", githubUsername, accessToken))
+	if err := ioutil.WriteFile(path.Join(u.HomeDir, ".git-credentials"), gitCredentials, 0644); err != nil {
+		return err
+	}
 	c := exec.Command("git", "config", "--global", "user.name", githubName)
 	c.Stdout = os.Stdout
 	c.Stderr = os.Stderr
diff --git a/internal/gapicgen/cmd/genbot/main.go b/internal/gapicgen/cmd/genbot/main.go
index 1853b6174900..028d223f349a 100644
--- a/internal/gapicgen/cmd/genbot/main.go
+++ b/internal/gapicgen/cmd/genbot/main.go
@@ -72,6 +72,18 @@ func main() {
 
 	flag.Usage = usage
 	flag.Parse()
+	if *githubAccessToken == "" {
+		*githubAccessToken = os.Getenv("GITHUB_ACCESS_TOKEN")
+	}
+	if *githubUsername == "" {
+		*githubUsername = os.Getenv("GITHUB_USERNAME")
+	}
+	if *githubName == "" {
+		*githubName = os.Getenv("GITHUB_NAME")
+	}
+	if *githubEmail == "" {
+		*githubEmail = os.Getenv("GITHUB_EMAIL")
+	}
 
 	for k, v := range map[string]string{
 		"githubAccessToken": *githubAccessToken,