From 331e7c13fa73fd1711b6629d7b2c6d5b17b30e1e Mon Sep 17 00:00:00 2001
From: Harvey Tindall <hrfee@protonmail.ch>
Date: Mon, 1 Dec 2025 14:18:10 +0000
Subject: [PATCH] Makefile: share $(DATA) on internal/external, keep record of
 build flags

This means you could make precompile, then make INTERNAL=on then make
INTERNAL=off and each time it would re-generate the go files only since
the flags have changed.
---
 Makefile    | 20 ++++++++++++++++----
 internal.go |  4 ++--
 2 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/Makefile b/Makefile
index a2c4b1a..8d05fa1 100644
--- a/Makefile
+++ b/Makefile
@@ -33,7 +33,7 @@ E2EE ?= on
 TAGS := -tags "
 
 ifeq ($(INTERNAL), on)
-	DATA := data
+	DATA := build/data
 	COMPDEPS := $(BUILDDEPS)
 else
 	DATA := build/data
@@ -102,6 +102,13 @@ else
 	SWAGINSTALL :=
 endif
 
+# FLAG HASHING: To rebuild on flag change.
+# credit for idea to https://bnikolic.co.uk/blog/sh/make/unix/2021/07/08/makefile.html
+rebuildFlags := GOESBUILD GOBINARY VERSION COMMIT UPDATER INTERNAL TRAY E2EE TAGS DEBUG RACE
+rebuildVals := $(foreach v,$(rebuildFlags),$(v)=$($(v)))
+rebuildHash := $(strip $(shell echo $(rebuildVals) | sha256sum | cut -d " " -f1))
+rebuildHashFile := $(DATA)/buildhash-$(rebuildHash).txt
+
 CONFIG_BASE = config/config-base.yaml
 
 # CONFIG_DESCRIPTION = $(DATA)/config-base.json
@@ -219,11 +226,16 @@ $(COPY_TARGET): $(INLINE_TARGET) $(STATIC_SRC) $(LANG_SRC) $(CONFIG_BASE)
 BUILDDEPS := $(DATA) $(CONFIG_DEFAULT) $(EMAIL_TARGET) $(COPY_TARGET) $(SWAGGER_TARGET) $(INLINE_TARGET) $(CSS_FULLTARGET) $(TYPESCRIPT_TARGET) 
 precompile: $(BUILDDEPS)
 
-COMPDEPS =
+COMPDEPS = $(rebuildHashFile)
 ifeq ($(INTERNAL), on)
-	COMPDEPS = $(BUILDDEPS)
+	COMPDEPS = $(BUILDDEPS) $(rebuildHashFile)
 endif
 
+$(rebuildHashFile):
+	$(info recording new flags $(rebuildVals))
+	rm -f $(DATA)/buildhash-*.txt
+	touch $(rebuildHashFile)
+
 GO_SRC = $(shell find ./ -name "*.go")
 GO_TARGET = build/jfa-go
 $(GO_TARGET): $(COMPDEPS) $(SWAGGER_TARGET) $(GO_SRC) go.mod go.sum
@@ -236,7 +248,7 @@ $(GO_TARGET): $(COMPDEPS) $(SWAGGER_TARGET) $(GO_SRC) go.mod go.sum
 test: $(BUILDDEPS) $(COMPDEPS) $(SWAGGER_TARGET) $(GO_SRC) go.mod go.sum
 	$(GOBINARY) test -ldflags="$(LDFLAGS)" $(TAGS) -p 1
 
-all: $(BUILDDEPS) $(GO_TARGET)
+all: $(BUILDDEPS) $(GO_TARGET) $(rebuildHashFile)
 
 compress:
 	upx --lzma $(GO_TARGET)
diff --git a/internal.go b/internal.go
index 0e521c5..0d69865 100644
--- a/internal.go
+++ b/internal.go
@@ -14,7 +14,7 @@ const binaryType = "internal"
 
 func BuildTagsExternal() {}
 
-//go:embed data data/html data/web data/web/css data/web/js
+//go:embed build/data build/data/html build/data/web build/data/web/css build/data/web/js
 var loFS embed.FS
 
 //go:embed lang/common lang/admin lang/email lang/form lang/setup lang/pwreset lang/telegram
@@ -38,6 +38,6 @@ func FSJoin(elem ...string) string {
 
 func loadFilesystems(rootDir string, logger *logger.Logger) {
 	langFS = rewriteFS{laFS, "lang/"}
-	localFS = rewriteFS{loFS, "data/"}
+	localFS = rewriteFS{loFS, "build/data/"}
 	logger.Println("Using internal storage")
 }