From 21db5c41660b439dc7246fb32afd14cb71a55264 Mon Sep 17 00:00:00 2001
From: grumbulon <grumbulon@grumbulon.xyz>
Date: Thu, 2 Feb 2023 18:02:22 -0500
Subject: [PATCH] add server death if cannot acccess DB with clean shutdown
 (drains connections), and other error handling, linting.

---
 cmd/pomme/main.go        | 26 +++++++++++++++++++++++++-
 internal/api/api_test.go |  5 ++++-
 internal/api/helpers.go  | 21 ++++++++++++++++-----
 internal/db/db.go        | 14 +++++++++-----
 4 files changed, 54 insertions(+), 12 deletions(-)

diff --git a/cmd/pomme/main.go b/cmd/pomme/main.go
index 14a736d..e8223e0 100644
--- a/cmd/pomme/main.go
+++ b/cmd/pomme/main.go
@@ -1,8 +1,11 @@
 package main
 
 import (
+	"context"
 	"log"
 	"net/http"
+	"os"
+	"os/signal"
 	"time"
 
 	_ "git.freecumextremist.com/grumbulon/pomme/docs"
@@ -49,5 +52,26 @@ func main() {
 		Handler:      pomme,
 	}
 
-	log.Fatal(s.ListenAndServe())
+	idleConnsClosed := make(chan struct{})
+
+	go func() {
+		sigint := make(chan os.Signal, 1)
+		signal.Notify(sigint, os.Interrupt)
+		<-sigint
+
+		// We received an interrupt signal, shut down.
+		if err := s.Shutdown(context.Background()); err != nil {
+			// Error from closing listeners, or context timeout:
+			log.Printf("HTTP server Shutdown: %v", err)
+		}
+
+		close(idleConnsClosed)
+	}()
+
+	if err := s.ListenAndServe(); err != http.ErrServerClosed { // nolint: goerr113
+		// Error starting or closing listener:
+		log.Fatalf("HTTP server ListenAndServe: %v", err)
+	}
+
+	<-idleConnsClosed
 }
diff --git a/internal/api/api_test.go b/internal/api/api_test.go
index d01d25b..e894ea9 100644
--- a/internal/api/api_test.go
+++ b/internal/api/api_test.go
@@ -78,7 +78,10 @@ func TestAPI(t *testing.T) {
 		assert.NotNil(t, err)
 	}
 
-	db := db.InitDb(c.TestDB)
+	db, err, ok := db.InitDb(c.TestDB)
+	if err != nil && !ok {
+		assert.NotNil(t, err)
+	}
 
 	hashedPassword, err := bcrypt.GenerateFromPassword([]byte(tester.password), bcrypt.DefaultCost)
 	if err != nil {
diff --git a/internal/api/helpers.go b/internal/api/helpers.go
index e31a1bc..cd26208 100644
--- a/internal/api/helpers.go
+++ b/internal/api/helpers.go
@@ -3,8 +3,8 @@ package api
 import (
 	"context"
 	"fmt"
-	"log"
 	"net/http"
+	"syscall"
 	"time"
 
 	"git.freecumextremist.com/grumbulon/pomme/internal"
@@ -17,17 +17,28 @@ import (
 // setDBMiddleware is the http Handler func for the GORM middleware with context.
 func setDBMiddleware(next http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		var pommeDB *gorm.DB
+		var (
+			pommeDB *gorm.DB
+			ok      bool
+		)
 		c, err := internal.ReadConfig()
 		if err != nil {
-			log.Printf("No config file defined: %v", err)
+			logHandler(genericResponseFields{"error": err.Error(), "message": "No config file defined:"})
 		}
 
 		switch r.Header.Get("User-Agent") {
 		case "pomme-api-test-slave":
-			pommeDB = db.InitDb(c.TestDB)
+			pommeDB, err, ok = db.InitDb(c.TestDB)
 		default:
-			pommeDB = db.InitDb(c.DB)
+			pommeDB, err, ok = db.InitDb(c.DB)
+		}
+
+		if err != nil && !ok {
+			logHandler(genericResponseFields{"error": err.Error(), "message": "Error initializing DB"})
+			err = syscall.Kill(syscall.Getpid(), syscall.SIGINT)
+			if err != nil {
+				panic("idk what to do with this but syscall.Kill errored out.")
+			}
 		}
 
 		timeoutContext, cancelContext := context.WithTimeout(context.Background(), time.Second)
diff --git a/internal/db/db.go b/internal/db/db.go
index 5209b55..0ad431e 100644
--- a/internal/db/db.go
+++ b/internal/db/db.go
@@ -1,23 +1,27 @@
 package db
 
 import (
+	"fmt"
+
 	"git.freecumextremist.com/grumbulon/pomme/internal"
 	"github.com/glebarez/sqlite"
 	"gorm.io/gorm"
 )
 
 // InitDb is the init function for the database.
-func InitDb(path string) *gorm.DB {
-	db, err := gorm.Open(sqlite.Open(path), &gorm.Config{})
+func InitDb(path string) (db *gorm.DB, err error, ok bool) {
+	ok = true
+	db, err = gorm.Open(sqlite.Open(path), &gorm.Config{})
+
 	if err != nil {
-		panic("failed to connect database")
+		return db, fmt.Errorf("failed to connect database: %w", err), !ok
 	}
 
 	// Migrate the schema
 	err = db.AutoMigrate(&internal.User{}, &internal.ZoneRequest{})
 	if err != nil {
-		panic("failed to run DB migration")
+		return &gorm.DB{}, fmt.Errorf("failed to run DB migration: %w", err), !ok
 	}
 
-	return db
+	return db, nil, ok
 }