在本地主机上使用 nanohttpd 作为服务器，如何在整个目录中提供静态 HTML 代码？

Question

我无法让 nanohttpd 工作。似乎无法www在应用程序的根目录中找到该目录。我的代码在https://github.com/tlkahn/neonx我在 MainActivity.java 的代码：@Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        BottomNavigationView navView = findViewById(R.id.nav_view);        mWebView = findViewById(R.id.webkit);        navView.setOnNavigationItemSelectedListener(mOnNavigationItemSelectedListener);        WebSettings webSettings = mWebView.getSettings();        webSettings.setMixedContentMode(WebSettings.MIXED_CONTENT_ALWAYS_ALLOW);        webSettings.setDomStorageEnabled(true);        mWebView.getSettings().setLoadsImagesAutomatically(true);        mWebView.getSettings().setJavaScriptEnabled(true);        mWebView.setScrollBarStyle(View.SCROLLBARS_INSIDE_OVERLAY);        mWebView.setWebViewClient(new WebViewClient() {            @Override            public boolean shouldOverrideUrlLoading(WebView view, WebResourceRequest request) {                return false;            }        });        if (!haveNetworkConnection()) {            new AlertDialog.Builder(this)                .setTitle("You are not connected to internet.")                .setMessage("Are you sure you want to exit?")                .setPositiveButton("Yes", new DialogInterface.OnClickListener() {                    @Override                    public void onClick(DialogInterface dialog, int which) {                        finishAffinity();                        System.exit(0);                    }                }).setNegativeButton("No", null).show();        }        startLocalServer(3000, "www", true, true );    }当我尝试访问时localhost:3000，出现错误：给定路径不是目录。错误似乎来自这一行： https: //git.io/fjS3f我猜我初始化 rootDir 的方式是错误的（这一行：https: //git.io/fjS3v）。但是我怎样才能使这项工作呢？我的意思是服务整个目录，这意味着所有 CSS/JS/hypyerlinks 应该工作，一旦 nanohttpd 开始服务......

Answer 1

问题是您无法像访问本地文件一样访问 assets 文件夹中的文件。您必须扩展 NanoHTTPD 并覆盖 serve(IHTTPSession) 才能提供资产。这是 Kotlin 中的示例。如果您看不懂，请告诉我，我会将其移植到 Java。

class FileServer(private val context: Context, port: Int) : NanoHTTPD(port) {

override fun serve(session: IHTTPSession): Response {

    val uri = session.uri.removePrefix("/").ifEmpty { "index.html" }

    println("Loading $uri")

    try {

        val mime = when (uri.substringAfterLast(".")) {

            "ico" -> "image/x-icon"

            "css" -> "text/css"

            "htm" -> "text/html"

            "html" -> "text/html"

            else -> "application/javascript"

        }

        return NanoHTTPD.newChunkedResponse(

            Response.Status.OK,

            mime,

            context.assets.open("www/$uri") // prefix with www because your files are not in the root folder in assets

        )

    } catch (e: Exception) {

        val message = "Failed to load asset $uri because $e"

        println(message)

        e.printStackTrace()

        return NanoHTTPD.newFixedLengthResponse(message)

    }

}

Answer 2

输出：

日志猫：

2019-08-05 15:21:53.838 10650-10650/com.neonxorg.neonx E/MainActivity: -------Assets List-----

2019-08-05 15:21:53.838 10650-10650/com.neonxorg.neonx E/MainActivity: asset-manifest.json

2019-08-05 15:21:53.838 10650-10650/com.neonxorg.neonx E/MainActivity: favicon.ico

2019-08-05 15:21:53.838 10650-10650/com.neonxorg.neonx E/MainActivity: index.html

2019-08-05 15:21:53.838 10650-10650/com.neonxorg.neonx E/MainActivity: manifest.json

2019-08-05 15:21:53.838 10650-10650/com.neonxorg.neonx E/MainActivity: precache-manifest.81af63d07b6dd6ae8e331187c522b020.js

2019-08-05 15:21:53.838 10650-10650/com.neonxorg.neonx E/MainActivity: service-worker.js

2019-08-05 15:21:53.838 10650-10650/com.neonxorg.neonx E/MainActivity: static

2019-08-05 15:21:53.842 10650-10650/com.neonxorg.neonx E/MainActivity: copyFolderFromAssets rootDirFullPath-www targetDirFullPath-/storage/emulated/0/Android/data/com.neonxorg.neonx/cache/www

2019-08-05 15:21:53.865 10650-10650/com.neonxorg.neonx E/MainActivity: copyFolderFromAssets rootDirFullPath-www/static targetDirFullPath-/storage/emulated/0/Android/data/com.neonxorg.neonx/cache/www/static

2019-08-05 15:21:53.867 10650-10650/com.neonxorg.neonx E/MainActivity: copyFolderFromAssets rootDirFullPath-www/static/css targetDirFullPath-/storage/emulated/0/Android/data/com.neonxorg.neonx/cache/www/static/css

2019-08-05 15:21:53.922 10650-10650/com.neonxorg.neonx E/MainActivity: copyFolderFromAssets rootDirFullPath-www/static/js targetDirFullPath-/storage/emulated/0/Android/data/com.neonxorg.neonx/cache/www/static/js

2019-08-05 15:21:54.352 10650-10650/com.neonxorg.neonx E/MainActivity: copyFolderFromAssets rootDirFullPath-www/static/media targetDirFullPath-/storage/emulated/0/Android/data/com.neonxorg.neonx/cache/www/static/media

2019-08-05 15:21:54.526 10650-10650/com.neonxorg.neonx E/MainActivity: -------Root File List-----

2019-08-05 15:21:54.528 10650-10650/com.neonxorg.neonx E/File: /storage/emulated/0/Android/data/com.neonxorg.neonx/cache/www/precache-manifest.81af63d07b6dd6ae8e331187c522b020.js

2019-08-05 15:21:54.528 10650-10650/com.neonxorg.neonx E/File: /storage/emulated/0/Android/data/com.neonxorg.neonx/cache/www/service-worker.js

2019-08-05 15:21:54.528 10650-10650/com.neonxorg.neonx E/File: /storage/emulated/0/Android/data/com.neonxorg.neonx/cache/www/static

2019-08-05 15:21:54.528 10650-10650/com.neonxorg.neonx E/File: /storage/emulated/0/Android/data/com.neonxorg.neonx/cache/www/favicon.ico

2019-08-05 15:21:54.528 10650-10650/com.neonxorg.neonx E/File: /storage/emulated/0/Android/data/com.neonxorg.neonx/cache/www/manifest.json

2019-08-05 15:21:54.528 10650-10650/com.neonxorg.neonx E/File: /storage/emulated/0/Android/data/com.neonxorg.neonx/cache/www/asset-manifest.json

2019-08-05 15:21:54.528 10650-10650/com.neonxorg.neonx E/File: /storage/emulated/0/Android/data/com.neonxorg.neonx/cache/www/index.html

2019-08-05 15:21:54.704 10650-10650/com.neonxorg.neonx E/MainActivity: Connected : Please access! http://192.168.1.2:3000 From a web browser

代码：

public final String TAG = getClass().getSimpleName();

public void startLocalServer(int port, String root, Boolean localhost, Boolean keepAlive) {

        try {

            String[] filePathList = (getAssets().list("www"));

            Log.e(TAG,"-------Assets List-----");

            for (String s : filePathList) {

                Log.e(TAG, s);

            }

            File externalCache = getExternalCacheDir();

            if (externalCache != null) {

                String path = externalCache.getAbsolutePath() + "/" + root;

                copyFolderFromAssets(getApplicationContext(), "www", path);

                File www_root = new File(path);

                Log.e(TAG,"-------Root File List-----");

                for (File f : www_root.listFiles()) {

                    Log.e("File ", f.getAbsolutePath());

                }

                server = new WebServer("localhost", port, www_root.getCanonicalFile());

                server.start();

                printIp();

            }

        } catch (IOException e) {

            Log.e(TAG, Log.getStackTraceString(e));

        }

    }

    public void copyFolderFromAssets(Context context, String rootDirFullPath, String targetDirFullPath) {

        Log.e(TAG,"copyFolderFromAssets " + "rootDirFullPath-" + rootDirFullPath + " targetDirFullPath-" + targetDirFullPath);

        File file = new File(targetDirFullPath);

        if (!file.exists()) {

            new File(targetDirFullPath).mkdirs();

        }

        try {

            String[] listFiles = context.getAssets().list(rootDirFullPath);// 遍历该目录下的文件和文件夹

            for (String string : listFiles) {// 看起子目录是文件还是文件夹，这里只好用.做区分了

                if (isFileByName(string)) {// 文件

                    copyFileFromAssets(context, rootDirFullPath + "/" + string, targetDirFullPath + "/" + string);

                } else {// 文件夹

                    String childRootDirFullPath = rootDirFullPath + "/" + string;

                    String childTargetDirFullPath = targetDirFullPath + "/" + string;

                    new File(childTargetDirFullPath).mkdirs();

                    copyFolderFromAssets(context, childRootDirFullPath, childTargetDirFullPath);

                }

            }

        } catch (IOException e) {

            Log.e(TAG, Log.getStackTraceString(e));

        }

    }

    public void copyFileFromAssets(Context context, String assetsFilePath, String targetFileFullPath) {

        InputStream assestsFileInputStream;

        try {

            assestsFileInputStream = context.getAssets().open(assetsFilePath);

            FileOutputStream fOS = new FileOutputStream(new File(targetFileFullPath));

            int length = -1;

            byte[] buf = new byte[1024];

            while ((length = assestsFileInputStream.read(buf)) != -1) {

                fOS.write(buf, 0, length);

            }

            fOS.flush();

        } catch (IOException e) {

            Log.e(TAG, Log.getStackTraceString(e));

        }

    }

    private boolean isFileByName(String str) {

        return str.contains(".");

    }

    private void printIp() {

        WifiManager wifiManager = (WifiManager) getApplicationContext().getSystemService(WIFI_SERVICE);

        int ipAddress = wifiManager.getConnectionInfo().getIpAddress();

        final String formatedIpAddress = String.format("%d.%d.%d.%d", (ipAddress & 0xff), (ipAddress >> 8 & 0xff),

                (ipAddress >> 16 & 0xff), (ipAddress >> 24 & 0xff));

        Log.e(TAG,"Connected : " + "Please access! http://" + formatedIpAddress + ":" + server.getListeningPort() + " From a web browser");

    }

给定路径不是目录。

当 nanphttpd 无法定位数据时，它会给出此错误。

为什么你没有得到实际的错误

在你正在使用的catch 块中，copyFolderFromAssets由于仅显示选定的应用程序过滤器，它可能不会显示在你的 LogCat 上copyFileFromAssetse.printStackTrace()

为了打印错误，您需要使用以下内容：

Log.e(TAG, Log.getStackTraceString(e));

我用 Log.e 语句替换了所有 System.out 和 e.printStackTrace。应用程序很可能无法将内容从 www 目录复制到目标目录。我将目标目录更改为缓存目录，它在我的设备上运行。（见下文）：

File externalCache = getExternalCacheDir();

if (externalCache != null) {

    String path = externalCache.getAbsolutePath() + "/" + root;

    File www_root = new File(path);

    copyFolderFromAssets(getApplicationContext(), "www", path);

    Log.e(TAG,"-------Root File List-----");

    for (File f : www_root.listFiles()) {

        Log.e("File ", f.getAbsolutePath());

    }

    server = new WebServer("localhost", port, www_root.getCanonicalFile());

    server.start();

    printIp();

}

边注：

static除非或除非您想将它们复制到实用程序类中，否则无需在这些函数中使用关键字