Cache go modules

Author: crazy-max

.github/workflows/build.yml

@@ -1,16 +1,26 @@
 name: build
 
 on:
-  pull_request:
-    branches: master
   push:
-    branches: master
-    tags: v*
+    branches: 'master'
+    tags: 'v*'
+    paths:
+      - '.github/workflows/build.yml'
+      - 'cmd/**'
+      - 'internal/**'
+      - '.goreleaser.yml'
+      - 'Dockerfile'
+      - 'go.mod'
+      - 'go.sum'
 
 jobs:
   go:
     runs-on: ubuntu-latest
     steps:
+      -
+        # https://github.com/actions/checkout
+        name: Checkout
+        uses: actions/checkout@v1
       -
         name: Prepare
         id: prepare
@@ -25,15 +35,14 @@ jobs:
         with:
           go-version: 1.12.10
       -
-        name: Set GOPATH
-        # temporary fix (see https://github.com/actions/setup-go/issues/14)
-        run: |
-          echo "##[set-env name=GOPATH;]$(dirname $GITHUB_WORKSPACE)"
-          echo "##[add-path]$(dirname $GITHUB_WORKSPACE)/bin"
-      -
-        # https://github.com/actions/checkout
-        name: Checkout
-        uses: actions/checkout@v1
+        # https://github.com/actions/cache
+        name: Cache Go modules
+        uses: actions/cache@v1
+        with:
+          path: ~/go/pkg/mod
+          key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
+          restore-keys: |
+            ${{ runner.os }}-go-
       -
         # https://github.com/goreleaser/goreleaser-action
         name: GoReleaser
@@ -59,6 +68,10 @@ jobs:
     runs-on: ubuntu-latest
     needs: go
     steps:
+      -
+        # https://github.com/actions/checkout
+        name: Checkout
+        uses: actions/checkout@v1
       -
         name: Prepare
         id: prepare
@@ -78,10 +91,6 @@ jobs:
         uses: crazy-max/ghaction-docker-buildx@v1
         with:
           version: latest
-      -
-        # https://github.com/actions/checkout
-        name: Checkout
-        uses: actions/checkout@v1
       -
         name: Docker Buildx (no push)
         run: |