Update Go version to 1.26 and adjust workflows and Dockerfile accordingly

Signed-off-by: Marc Schäfer <git@marcschaeferger.de>

.github/workflows/test.yml

@@ -16,10 +16,14 @@ jobs:
     steps:
       - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
 
+      - name: Read go version
+        id: goversion
+        run: echo "version=$(cat .go-version)" >> $GITHUB_OUTPUT
+
       - name: Set up Go
         uses: actions/setup-go@4b73464bb391d4059bd26b0524d20df3927bd417 # v6.3.0
         with:
-          go-version: 1.25
+          go-version: ${{ steps.goversion.outputs.version }}
 
       - name: Build go
         run: go build

.go-version

@@ -1 +1 @@
-1.25
+1.26

Dockerfile

@@ -1,4 +1,5 @@
-FROM golang:1.26-alpine AS builder
+ARG GO_VERSION=1.26
+FROM golang:${GO_VERSION}-alpine AS builder
 
 # Set the working directory inside the container
 WORKDIR /app
@@ -25,4 +26,4 @@ COPY entrypoint.sh /
 
 RUN chmod +x /entrypoint.sh
 ENTRYPOINT ["/entrypoint.sh"]
-CMD ["gerbil"]
+CMD ["gerbil"]

Makefile

@@ -1,4 +1,6 @@
 
+GO_VERSION := $(shell cat .go-version 2>/dev/null)
+
 all: build push
 
 docker-build-release:
@@ -7,10 +9,10 @@ docker-build-release:
 		exit 1; \
 	fi
 	docker buildx build --platform linux/arm64,linux/amd64 -t fosrl/gerbil:latest -f Dockerfile --push .
-	docker buildx build --platform linux/arm64,linux/amd64 -t fosrl/gerbil:$(tag) -f Dockerfile --push .
+	docker buildx build --platform linux/arm64,linux/amd64 -t fosrl/gerbil:$(tag) -f Dockerfile --build-arg GO_VERSION=$(GO_VERSION) --push .
 
 build:
-	docker build -t fosrl/gerbil:latest .
+	docker build -t fosrl/gerbil:latest --build-arg GO_VERSION=$(GO_VERSION) .
 
 push:
 	docker push fosrl/gerbil:latest