Embed templates and statics into package (#48)

* Embed templates and statics into package
* Make mbtileserver 'go get'-able

README.md

@@ -34,10 +34,14 @@ virtual machine without any issues.
 
 
 ## Installation
-Currently, this project is not `go get`-able because static assets and 
-templates are not downloaded via `go get`.  We're working toward this.
+You can install this project with 
+
+```sh
+go get github.com/consbio/mbtileserver
+```
+
+This will create and install an executable called `mbtileserver`.
 
-In the meantime, clone this repository using your `git` tool of choice.
 
 This uses `Govendor` tool, so dependencies ship with the repo for easier builds.
 
@@ -49,16 +53,12 @@ Dependencies:
 * [github.com/Sirupsen/logrus](https://github.com/Sirupsen/logrus)
 * [golang.org/x/crypto/acme/autocert](https://golang.org/x/crypto/acme/autocert)
 
+Development Dependencies (only needed when modifying the code):
+* [github.com/shurcooL/vfsgen](https://github.com/shurcooL/vfsgen)
+
 On Windows, it is necessary to install `gcc` in order to compile `mattn/go-sqlite3`.  
 MinGW or [TDM-GCC](https://sourceforge.net/projects/tdm-gcc/) should work fine.
 
-Then build it:
-```
-go build .
-```
-
-This will create an executable called `mbtileserver`.
-
 
 If you experience very slow builds each time, it may be that you need to first run
 ```
@@ -69,9 +69,9 @@ to make subsequent builds much faster.
 
 
 ## Usage
-From within the repository root:
+From within the repository root ($GOPATH/bin needs to be in in your $PATH):
 ```
-$  ./mbtileserver --help
+$  mbtileserver --help
 Serve tiles from mbtiles files.
 
 Usage:
@@ -203,7 +203,6 @@ See the issues tagged to the [0.5 version](https://github.com/consbio/mbtileserv
 for our near term features and improvements.
 
 In short, we are planning to:
-* make this project `go get`-able
 * add tests and benchmarks
 * get things production ready
 
@@ -212,7 +211,7 @@ In short, we are planning to:
 Development of the templates and static assets likely requires using
 `node` and `npm`.  Install these tools in the normal way.
 
-From the `templates/static` folder, run
+From the `handlers/templates/static` folder, run
 ```
 $npm install
 ```
@@ -225,7 +224,21 @@ Then to build the minified version, run:
 $gulp build
 ```
 
+Modifying the `.go` files always requires re-running `go build`.
+
+In case you have modified the templates and static assets, you need to run `go
+generate` from the `handlers` sub-directory to ensure that your modifications
+are embedded into the executable. For this to work, you must have
+[github.com/shurcooL/vfsgen)[https://github.com/shurcooL/vfsgen) installed.
+This will rewrite the `assets_vfsdata.go` which you must commit along with your
+modification. Also you should run `go build` after `go generate`.
+
+During the development cycle you may use `go build -tags dev` to build the
+binary, in which case it will always take the assets from the relative file
+path `handlers/templates/` directly and you can omit the `go generate` step.
+But do not forget to perform it in the end.
+
+
 
-Modifying the `go` files requires re-running `go build`.
 
 

handlers/assets.go

@@ -0,0 +1,10 @@
+// +build dev
+
+package handlers
+
+import (
+	"net/http"
+)
+
+// Assets contains project assets.
+var Assets http.FileSystem = http.Dir("templates")

handlers/assets_generate.go

@@ -0,0 +1,21 @@
+// +build ignore
+
+package main
+
+import (
+	"log"
+
+	"github.com/consbio/mbtileserver/handlers"
+	"github.com/shurcooL/vfsgen"
+)
+
+func main() {
+	err := vfsgen.Generate(handlers.Assets, vfsgen.Options{
+		PackageName:  "handlers",
+		BuildTags:    "!dev",
+		VariableName: "Assets",
+	})
+	if err != nil {
+		log.Fatalln(err)
+	}
+}

handlers/handlers.go

@@ -1,5 +1,7 @@
 package handlers
 
+//go:generate go run -tags=dev assets_generate.go
+
 import (
 	"encoding/json"
 	"fmt"

handlers/static.go

@@ -0,0 +1,26 @@
+package handlers
+
+import (
+	"net/http"
+	"path"
+	"time"
+)
+
+// Static returns an http.Handler that will serve the contents of
+// the subdirectory "/static/dist" of the Assets.
+func Static() http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		f, err := Assets.Open(path.Join("/static/dist", r.URL.Path))
+		if err != nil {
+			http.Error(w, http.StatusText(http.StatusNotFound), http.StatusNotFound)
+			return
+		}
+		defer f.Close()
+		mtime := time.Now()
+		st, err := f.Stat()
+		if err == nil {
+			mtime = st.ModTime()
+		}
+		http.ServeContent(w, r, path.Base(r.URL.Path), mtime, f)
+	})
+}

handlers/templates.go

@@ -0,0 +1,52 @@
+package handlers
+
+import (
+	"html/template"
+	"io/ioutil"
+	"path"
+	"strings"
+)
+
+// TemplatesFromAssets returns the HTML templates from the assets filesystem.
+// It has a signature that allows it to be used with templates.Must.
+func TemplatesFromAssets() (*template.Template, error) {
+	t := template.New("_base_")
+	d, err := Assets.Open("/")
+	if err != nil {
+		return t, err
+	}
+	files, err := d.Readdir(0)
+	if err != nil {
+		return t, err
+	}
+	for _, file := range files {
+		name := file.Name()
+		ext := strings.ToLower(path.Ext(name))
+		if ext != ".html" || file.IsDir() {
+			continue
+		}
+		name = name[:len(name)-len(ext)]
+		if _, err := tmplFromAssets(t, name); err != nil {
+			return t, err
+		}
+	}
+	return t, nil
+}
+
+// tmplFromAssets returns the HTML templates from the assets filesystem.
+func tmplFromAssets(t *template.Template, name string) (*template.Template, error) {
+	f, err := Assets.Open("/" + name + ".html")
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+	buf, err := ioutil.ReadAll(f)
+	if err != nil {
+		return nil, err
+	}
+	t, err = t.New(name).Parse(string(buf))
+	if err != nil {
+		return nil, err
+	}
+	return t, nil
+}

main.go

@@ -194,7 +194,7 @@ func serve() {
 	e.Use(middleware.CORS())
 
 	t := &Template{
-		templates: template.Must(template.ParseGlob("templates/*.html")),
+		templates: template.Must(handlers.TemplatesFromAssets()),
 	}
 	e.Renderer = t
 
@@ -205,7 +205,12 @@ func serve() {
 	e.File("/favicon.png", "favicon.png")
 
 	// TODO: can use more caching here
-	e.Group(fmt.Sprintf("/%s/static/", pathPrefix), gzip, middleware.Static("templates/static/dist/"))
+	staticPrefix := "/static"
+	if pathPrefix != "" {
+		staticPrefix = "/" + pathPrefix + staticPrefix
+	}
+	staticHandler := http.StripPrefix(staticPrefix, handlers.Static())
+	e.GET(staticPrefix+"*", echo.WrapHandler(staticHandler), gzip)
 
 	e.GET("/services", ListServices, NotModifiedMiddleware, gzip)
 

main_dev.go

@@ -0,0 +1,16 @@
+// +build dev
+
+package main
+
+import (
+	"net/http"
+
+	"github.com/consbio/mbtileserver/handlers"
+)
+
+// This is an temporary vehicle until we can stop serving the assets from the
+// main package (that is, until https://github.com/consbio/mbtileserver/pull/47
+// is merged). Afterwards, it is safe to remove this whole file.
+func init() {
+	handlers.Assets = http.Dir("handlers/templates")
+}