Migrating to Go and Dockerizing

.gitignore

@@ -1,9 +1,5 @@
-/vendor/
-composer.lock
-composer.phar
-/var/
 *.swp
 .idea/
-/config/config.yml
-/web/js/config.js
-/web/s/
+/gen/
+/tmp/
+*-linux-amd64

Makefile

@@ -0,0 +1,21 @@
+GOFLAGS := --ldflags '-w -linkmode external'
+CC := $(shell which musl-clang)
+
+all: images
+
+STATIC_FILES := $(wildcard static/*)
+
+images: coverservice/coverservice-linux-amd64 \
+		coverservice/Dockerfile \
+		nginx/Dockerfile \
+		docker-compose.yml
+	docker-compose build
+
+COMMON_FILES := $(wildcard common/*.go)
+
+coverservice/coverservice-linux-amd64: \
+		$(COMMON_FILES) \
+		coverservice/main.go \
+		$(wildcard coverservice/service/*.go)
+	cd coverservice && \
+	CC=${CC} go build ${GOFLAGS} -o coverservice-linux-amd64

common/handlers.go

@@ -0,0 +1,27 @@
+package common
+
+import (
+    "net/http"
+    "strconv"
+    "encoding/json"
+)
+
+const kInternalError = "An internal error occurred"
+
+type ErrorResponse struct {
+    Error string `json:"error"`
+}
+
+
+func WriteJsonResponse(w http.ResponseWriter, status int, data []byte) {
+    w.Header().Set("Content-Type", "application/json")
+    w.Header().Set("Content-Length", strconv.Itoa(len(data)))
+    w.WriteHeader(status)
+    w.Write(data)
+}
+
+
+func WriteInternalErrorResponse(w http.ResponseWriter) {
+    data, _ := json.Marshal(ErrorResponse{kInternalError})
+    WriteJsonResponse(w, http.StatusInternalServerError, data)
+}

common/router.go

@@ -0,0 +1,18 @@
+package common
+
+
+import "github.com/gorilla/mux"
+
+
+func NewRouter(routes Routes) *mux.Router {
+    router := mux.NewRouter().StrictSlash(true)
+
+    for _, route := range routes {
+        router.Methods(route.Method).
+        Path(route.Pattern).
+        Name(route.Name).
+        Handler(route.HandlerFunc)
+    }
+
+    return router
+}

common/routes.go

@@ -0,0 +1,13 @@
+package common
+
+import "net/http"
+
+
+type Route struct {
+    Name string
+    Method string
+    Pattern string
+    HandlerFunc http.HandlerFunc
+}
+
+type Routes []Route

common/utils.go

@@ -0,0 +1,36 @@
+package common
+
+import (
+    "os"
+    "io"
+)
+
+func CopyFile(src, dst string) (int64, error) {
+    sf, err := os.Open(src)
+    if err != nil {
+        return 0, err
+    }
+    defer sf.Close()
+    df, err := os.Create(dst)
+    if err != nil {
+        return 0, err
+    }
+    defer df.Close()
+    return io.Copy(df, sf)
+}
+
+
+func MoveFile(src, dst string) error {
+    err := os.Rename(src, dst)
+    if err != nil {
+        _, err = CopyFile(src, dst)
+        if err != nil {
+            return err
+        }
+        err = os.Remove(src)
+        if err != nil {
+            return err
+        }
+    }
+    return nil
+}

common/webserver.go

@@ -0,0 +1,19 @@
+package common
+
+
+import (
+    "net/http"
+    "github.com/sirupsen/logrus"
+)
+
+
+func StartWebServer(port string, routes Routes) {
+    r := NewRouter(routes)
+    http.Handle("/", r)
+    logrus.Infof("Starting HTTP service at port %s", port)
+    err := http.ListenAndServe(":" + port, nil)
+    if err != nil {
+        logrus.Errorf("An error ocurred starting HTTP listener at port %s", port)
+        logrus.Error("Error: " + err.Error())
+    }
+}

coverservice/Dockerfile

@@ -0,0 +1,17 @@
+FROM ubuntu:16.04
+
+EXPOSE 8000
+
+RUN apt update && \
+    apt install -y --no-install-recommends texlive-latex-base texlive-fonts-recommended musl && \
+    rm -rf /var/lib/apt/lists/*
+
+WORKDIR "/srv/coverservice"
+
+COPY coverservice/docker-entrypoint.sh /entrypoint.sh
+COPY img/ucsp.png img/
+COPY templates/cover.tex templates/
+COPY coverservice/coverservice-linux-amd64 server
+
+ENTRYPOINT ["/entrypoint.sh"]
+CMD ["./server"]

coverservice/docker-entrypoint.sh

@@ -0,0 +1,5 @@
+#!/bin/sh
+
+mkdir -p tmp gen
+
+exec "$@"

coverservice/main.go

@@ -0,0 +1,15 @@
+package main
+
+import (
+    "math/rand"
+    "time"
+    "github.com/sirupsen/logrus"
+    "github.com/ACMUCSP/mkcaratula/common"
+    "github.com/ACMUCSP/mkcaratula/coverservice/service"
+)
+
+func main() {
+    logrus.Infof("Starting %s", service.AppName)
+    rand.Seed(time.Now().UnixNano())
+    common.StartWebServer("8000", service.Routes)
+}