Add drone auto build capabilities

.drone.yml

@@ -0,0 +1,56 @@
+kind: pipeline
+type: docker
+name: default
+
+steps:
+  - name: build
+    image: docker:dind
+    volumes:
+      - name: dockersock
+        path: /var/run
+      - name: build
+        path: /build
+    commands:
+      - echo "Building gotify version $GOTIFY_VERSION"
+      - sleep 5 # give docker enough time to start
+      - docker ps -a
+      - apk --no-cache add build-base git go
+      - export PATH=$PATH:$HOME/go/bin
+      - make -e build
+      - ls build
+      - cp build/*.so /build
+  - name: publish
+    image: tystuyfzand/drone-github-release
+    volumes:
+      - name: build
+        path: /build
+    settings:
+      api_key:
+        from_secret: github_api_key
+      files:
+        - /build/*.so
+      title: "MQTT for Gotify ${GOTIFY_VERSION}"
+      tag_name: "latest-gotify-${GOTIFY_VERSION}"
+      checksum:
+        - md5
+        - sha1
+        - sha256
+        - sha512
+
+services:
+  - name: docker
+    image: docker:dind
+    privileged: true
+    volumes:
+      - name: dockersock
+        path: /var/run
+
+volumes:
+  - name: dockersock
+    temp: {}
+  - name: build
+    temp: {}
+
+trigger:
+  event:
+    - custom

Makefile

@@ -5,25 +5,25 @@ PLUGIN_ENTRY=plugin.go
 GO_VERSION=`cat $(BUILDDIR)/gotify-server-go-version`
 DOCKER_BUILD_IMAGE=gotify/build
 DOCKER_WORKDIR=/proj
-DOCKER_RUN=docker run --rm -v "$$PWD/.:${DOCKER_WORKDIR}" -v "`go env GOPATH`/pkg/mod/.:/go/pkg/mod:ro" -w ${DOCKER_WORKDIR}
+DOCKER_RUN=docker run --rm -v "$$PWD/.:${DOCKER_WORKDIR}" -v "`go env GOPATH`/pkg/mod/.:/go/pkg/mod" -w ${DOCKER_WORKDIR}
 DOCKER_GO_BUILD=go build -mod=readonly -a -installsuffix cgo -ldflags "$$LD_FLAGS" -buildmode=plugin
 
 download-tools:
-	GO111MODULE=off go get -u github.com/gotify/plugin-api/cmd/gomod-cap
+	go install github.com/gotify/plugin-api/cmd/gomod-cap@latest
 
 create-build-dir:
 	mkdir -p ${BUILDDIR} || true
 
 update-go-mod: create-build-dir download-tools
-	wget -LO ${BUILDDIR}/gotify-server.mod https://raw.githubusercontent.com/gotify/server/${GOTIFY_VERSION}/go.mod
+	wget -O ${BUILDDIR}/gotify-server.mod https://raw.githubusercontent.com/gotify/server/${GOTIFY_VERSION}/go.mod
 	gomod-cap -from ${BUILDDIR}/gotify-server.mod -to go.mod
 	rm ${BUILDDIR}/gotify-server.mod || true
 	go mod edit -require=github.com/gotify/server$(shell echo "/${GOTIFY_VERSION}" | egrep -o "^/v[2-9][0-9]*")@${GOTIFY_VERSION}
 	go mod tidy
 
 get-gotify-server-go-version: create-build-dir
 	rm ${BUILDDIR}/gotify-server-go-version || true
-	wget -LO ${BUILDDIR}/gotify-server-go-version https://raw.githubusercontent.com/gotify/server/${GOTIFY_VERSION}/GO_VERSION
+	wget -O ${BUILDDIR}/gotify-server-go-version https://raw.githubusercontent.com/gotify/server/${GOTIFY_VERSION}/GO_VERSION
 
 build-linux-amd64: get-gotify-server-go-version update-go-mod
 	${DOCKER_RUN} ${DOCKER_BUILD_IMAGE}:$(GO_VERSION)-linux-amd64 ${DOCKER_GO_BUILD} -o ${BUILDDIR}/${PLUGIN_NAME}-linux-amd64${FILE_SUFFIX}.so ${DOCKER_WORKDIR}