Support PHP-FPM overrides via environment variables

Author: iamacarpet

cmd/php/supervisor/main.go

@@ -70,6 +70,11 @@ func buildFn(ctx *gcp.Context) error {
 	overrides := webconfig.OverriddenProperties(ctx, runtimeConfig)
 	webconfig.SetEnvVariables(l, overrides)
 
+	err = overrides.UpdateFromEnvironment(ctx)
+	if err != nil {
+		return err
+	}
+
 	fpmConfFile, err := writeFpmConfig(l.Path, overrides)
 	if err != nil {
 		return err
@@ -164,11 +169,17 @@ func nginxConfig(layer string, overrides webconfig.OverrideProperties) nginx.Con
 		frontController = overrides.FrontController
 	}
 
+	root := defaultRoot
+	if overrides.DocumentRoot != "" {
+		root = filepath.Join(defaultRoot, overrides.DocumentRoot)
+	}
+
 	nginx := nginx.Config{
 		Port:                  defaultNginxPort,
 		FrontControllerScript: frontController,
-		Root:                  filepath.Join(defaultRoot, overrides.DocumentRoot),
+		Root:                  root,
 		AppListenAddress:      defaultAddress,
+		ServesStaticFiles:     overrides.NginxServesStaticFiles,
 	}
 
 	if overrides.NginxServerConfInclude {
@@ -205,6 +216,14 @@ func fpmConfig(layer string, overrides webconfig.OverrideProperties) (nginx.FPMC
 		AddNoDecorateWorkers: true,
 	}
 
+	if overrides.PHPFPMDynamicWorkers {
+		fpm.DynamicWorkers = overrides.PHPFPMDynamicWorkers
+	}
+
+	if overrides.PHPFPMWorkers > 0 {
+		fpm.NumWorkers = overrides.PHPFPMWorkers
+	}
+
 	if overrides.PHPFPMOverride {
 		fpm.ConfOverride = overrides.PHPFPMOverrideFileName
 	}

cmd/php/webconfig/main.go

@@ -82,21 +82,10 @@ func buildFn(ctx *gcp.Context) error {
 		webconfig.SetEnvVariables(l, overrides)
 	}
 
-	if customNginxConf, present := os.LookupEnv(php.CustomNginxConfig); present {
-		overrides.NginxConfOverride = true
-		overrides.NginxConfOverrideFileName = filepath.Join(defaultRoot, customNginxConf)
-	}
-
-	nginxServesStaticFiles, err := env.IsPresentAndTrue(php.NginxServesStaticFiles)
+	err = overrides.UpdateFromEnvironment(ctx)
 	if err != nil {
 		return err
 	}
-	overrides.NginxServesStaticFiles = nginxServesStaticFiles
-
-	nginxDocumentRoot := os.Getenv(php.NginxDocumentRoot)
-	if (nginxDocumentRoot != "") {
-		overrides.DocumentRoot = nginxDocumentRoot
-	}
 
 	fpmConfFile, err := writeFpmConfig(ctx, l.Path, overrides)
 	if err != nil {
@@ -211,6 +200,14 @@ func fpmConfig(layer string, addNoDecorateWorkers bool, overrides webconfig.Over
 		fpm.ListenAddress = defaultFlexAddress
 	}
 
+	if overrides.PHPFPMDynamicWorkers {
+		fpm.DynamicWorkers = overrides.PHPFPMDynamicWorkers
+	}
+
+	if overrides.PHPFPMWorkers > 0 {
+		fpm.NumWorkers = overrides.PHPFPMWorkers
+	}
+
 	if overrides.PHPFPMOverride {
 		fpm.ConfOverride = overrides.PHPFPMOverrideFileName
 	}

pkg/env/env.go

@@ -194,3 +194,18 @@ func IsPresentAndTrue(varName string) (bool, error) {
 
 	return parsed, nil
 }
+
+// IsPresentAndInt returns true and the integer value if the environment variable evaluates exists and contains an integer.
+func IsPresentAndInt(varName string) (bool, int, error) {
+	varValue, present := os.LookupEnv(varName)
+	if !present {
+		return false, 0, nil
+	}
+
+	parsed, err := strconv.Atoi(varValue)
+	if err != nil {
+		return false, 0, fmt.Errorf("parsing %s: %v", varName, err)
+	}
+
+	return true, parsed, nil
+}

pkg/php/php.go

@@ -91,11 +91,17 @@ post_max_size = 32M
 	// CustomNginxConfig is an environment variable to pass a custom nginx configuration.
 	CustomNginxConfig = "GOOGLE_CUSTOM_NGINX_CONFIG"
 
-	// NginxServesStaticFiles is an environment variable to configure Nginx to serve static files.
+	// NginxServesStaticFiles is an environment variable to configure nginx to serve static files.
 	NginxServesStaticFiles = "NGINX_SERVES_STATIC_FILES"
 
-	// NginxDocumentRoot overrides the document root of nginx.
+	// NginxDocumentRoot is an environment variable to configure the document root of nginx.
 	NginxDocumentRoot = "NGINX_DOCUMENT_ROOT"
+
+	// PHPFPMDynamicWorkers is an environment variable to enable dynamic workers for php-fpm.
+	PHPFPMDynamicWorkers = "PHP_FPM_DYNAMIC_WORKERS"
+
+	// PHPFPMWorkerCount is an environment variable to configure the number of php-fpm workers.
+	PHPFPMWorkerCount = "PHP_FPM_WORKER_COUNT"
 )
 
 type composerScriptsJSON struct {

pkg/webconfig/BUILD.bazel

@@ -9,6 +9,7 @@ go_library(
     ],
     deps = [
         "//pkg/appyaml",
+        "//pkg/env",
         "//pkg/gcpbuildpack",
         "//pkg/php",
         "@com_github_buildpacks_libcnb//:go_default_library",

pkg/webconfig/webconfig.go

@@ -2,9 +2,12 @@
 package webconfig
 
 import (
+	"fmt"
+	"os"
 	"path/filepath"
 
 	"github.com/GoogleCloudPlatform/buildpacks/pkg/appyaml"
+	"github.com/GoogleCloudPlatform/buildpacks/pkg/env"
 	gcp "github.com/GoogleCloudPlatform/buildpacks/pkg/gcpbuildpack"
 	"github.com/GoogleCloudPlatform/buildpacks/pkg/php"
 	"github.com/buildpacks/libcnb"
@@ -44,6 +47,10 @@ type OverrideProperties struct {
 	NginxHTTPInclude bool
 	// NginxHTTPIncludeFileName name of the partial nginx config to be included in the http section.
 	NginxHTTPIncludeFileName string
+	// PHPFPMDynamicWorkers boolean to toggle dynamic workers in the php-fpm config file.
+	PHPFPMDynamicWorkers bool
+	// PHPFPMWorkers integer to specify the worker thread count in the php-fpm config file.
+	PHPFPMWorkers int
 	// PHPFPMOverride boolean to check if user-provided php-fpm config exists.
 	PHPFPMOverride bool
 	// PHPFPMOverrideFileName name of the user-provided php-fpm config file.
@@ -56,6 +63,44 @@ type OverrideProperties struct {
 	NginxServesStaticFiles bool
 }
 
+func (overrides *OverrideProperties) UpdateFromEnvironment(ctx *gcp.Context) error {
+	if customNginxConf, present := os.LookupEnv(php.CustomNginxConfig); present {
+		overrides.NginxConfOverride = true
+		overrides.NginxConfOverrideFileName = filepath.Join(defaultRoot, customNginxConf)
+	}
+
+	nginxServesStaticFiles, err := env.IsPresentAndTrue(php.NginxServesStaticFiles)
+	if err != nil {
+		return err
+	}
+	overrides.NginxServesStaticFiles = nginxServesStaticFiles
+
+	nginxDocumentRoot := os.Getenv(php.NginxDocumentRoot)
+	if nginxDocumentRoot != "" {
+		overrides.DocumentRoot = nginxDocumentRoot
+	}
+
+	phpFPMDynamicWorkers, err := env.IsPresentAndTrue(php.PHPFPMDynamicWorkers)
+	if err != nil {
+		return err
+	}
+	overrides.PHPFPMDynamicWorkers = phpFPMDynamicWorkers
+
+	phpFPMWorkerCountPresent, phpFPMWorkerCount, err := env.IsPresentAndInt(php.PHPFPMWorkerCount)
+	if err != nil {
+		return err
+	}
+	if phpFPMWorkerCountPresent {
+		if phpFPMWorkerCount > 0 {
+			overrides.PHPFPMWorkers = phpFPMWorkerCount
+		} else {
+			return fmt.Errorf("invalid %s value, must be greater than 0", php.PHPFPMWorkerCount)
+		}
+	}
+
+	return nil
+}
+
 // OverriddenProperties returns whether the property has been overridden and the path to the file.
 func OverriddenProperties(ctx *gcp.Context, runtimeConfig appyaml.RuntimeConfig) OverrideProperties {
 	phpIniOverride, phpIniOverrideFileName := overrideProperties(ctx, runtimeConfig.PHPIniOverride, defaultPHPIni)