Add new GlobalDocument request routing mode

Summary:
I added a new config option, "GlobalDocument", designed to better suit applications that use a request routing framework and have a single Hack entry point that handles every URI.

Previously the following config and file structure were required:

```
# config.hdf
Server {
  ErrorDocument404 = index.php
}
VirtualHost {
  default {
    PathTranslation = html
  }
}
# file structure
lib:
  utils.php
  ...
html:
  index.php
```

With this new option the following is possible:
```
# config.hdf
Server {
  GlobalDocument = lib/__entrypoint.php
}
# file structure
lib:
  utils.php
  __entrypoint.php
  ...
```

This removes the need for a document folder entirely and ensures that every request must go through the single entrypoint. Further, this entrypoint can now be placed in the same folder / module as the rest of the routing framework's core code.

Reviewed By: billf

Differential Revision: D17131684

fbshipit-source-id: 15a2e22ec13f21df31bfd25fee77d129e074f174

Author: Will Shackleton

hphp/runtime/base/runtime-option.cpp

@@ -694,6 +694,7 @@ bool RuntimeOption::AutoloadEnabled;
 std::string RuntimeOption::AutoloadDBPath;
 std::string RuntimeOption::FileCache;
 std::string RuntimeOption::DefaultDocument;
+std::string RuntimeOption::GlobalDocument;
 std::string RuntimeOption::ErrorDocument404;
 bool RuntimeOption::ForbiddenAs404 = false;
 std::string RuntimeOption::ErrorDocument500;
@@ -2245,6 +2246,7 @@ void RuntimeOption::Load(
     Config::Bind(FileCache, ini, config, "Server.FileCache");
     Config::Bind(DefaultDocument, ini, config, "Server.DefaultDocument",
                  "index.php");
+    Config::Bind(GlobalDocument, ini, config, "Server.GlobalDocument");
     Config::Bind(ErrorDocument404, ini, config, "Server.ErrorDocument404");
     normalizePath(ErrorDocument404);
     Config::Bind(ForbiddenAs404, ini, config, "Server.ForbiddenAs404");

hphp/runtime/base/runtime-option.h

@@ -416,6 +416,7 @@ struct RuntimeOption {
 
   static std::string FileCache;
   static std::string DefaultDocument;
+  static std::string GlobalDocument;
   static std::string ErrorDocument404;
   static bool ForbiddenAs404;
   static std::string ErrorDocument500;

hphp/runtime/server/http-protocol.cpp

@@ -666,6 +666,9 @@ static void CopyPathInfo(Array& server,
         name = name.substr(0, pos);
       }
     }
+    if (r.globalDoc()) {
+      name = String(RuntimeOption::GlobalDocument);
+    }
     if (r.defaultDoc()) {
       if (!name.empty() && name[name.length() - 1] != '/') {
         name += "/";

hphp/runtime/server/request-uri.cpp

@@ -34,8 +34,13 @@ namespace HPHP {
 RequestURI::RequestURI(const VirtualHost *vhost, Transport *transport,
                        const std::string &pathTranslation,
                        const std::string &sourceRoot)
-  :  m_rewritten(false), m_defaultDoc(false), m_done(false),
-     m_forbidden(false), m_ext(nullptr) {
+  : m_rewritten(false)
+  , m_defaultDoc(false)
+  , m_globalDoc(false)
+  , m_done(false)
+  , m_forbidden(false)
+  , m_ext(nullptr)
+{
   if (!process(vhost, transport, sourceRoot, pathTranslation,
                transport->getServerObject()) ||
       (m_forbidden && RuntimeOption::ForbiddenAs404)) {
@@ -64,7 +69,11 @@ RequestURI::RequestURI(const VirtualHost *vhost, Transport *transport,
 }
 
 RequestURI::RequestURI(const std::string & rpcFunc)
-  :  m_rewritten(false), m_defaultDoc(false), m_done(false) {
+  : m_rewritten(false)
+  , m_defaultDoc(false)
+  , m_globalDoc(false)
+  , m_done(false)
+{
   m_originalURL = m_rewrittenURL = m_resolvedURL = String(rpcFunc);
 }
 
@@ -99,6 +108,25 @@ bool RequestURI::process(const VirtualHost *vhost, Transport *transport,
     return true;
   }
 
+  if (!RuntimeOption::GlobalDocument.empty()) {
+    // GlobalDocument option in use - never resolveURL and 404 if GlobalDocument
+    // does not exist. Still check for rewrites.
+
+    if (!rewriteURL(vhost, transport, pathTranslation, sourceRoot)) {
+      // Redirection
+      m_done = true;
+      return true;
+    }
+
+    m_resolvedURL = String(RuntimeOption::GlobalDocument);
+    if (virtualFileExists(vhost, sourceRoot, pathTranslation,
+                          m_resolvedURL)) {
+      m_globalDoc = true;
+      return true;
+    }
+    return false;
+  }
+
   // Fast path for files that exist
   if (vhost->checkExistenceBeforeRewrite()) {
     String canon = FileUtil::canonicalize(m_originalURL);

hphp/runtime/server/request-uri.h

@@ -43,6 +43,7 @@ struct RequestURI {
 
   bool rewritten() const { return m_rewritten; }
   bool defaultDoc() const { return m_defaultDoc; }
+  bool globalDoc() const { return m_globalDoc; }
   bool done() const { return m_done; }
   bool forbidden() const { return m_forbidden; }
 
@@ -64,6 +65,7 @@ struct RequestURI {
 
   bool m_rewritten;  // whether rewrite rules have applied
   bool m_defaultDoc; // whether DefaultDocument was appended
+  bool m_globalDoc; // whether GlobalDocument was used
   bool m_done;
   bool m_forbidden;
   const char *m_ext;   // file extension
@@ -74,6 +76,9 @@ struct RequestURI {
   bool rewriteURL(const VirtualHost *vhost, Transport *transport,
                   const std::string &pathTranslation,
                   const std::string &sourceRoot);
+  bool resolveGlobalURL(const VirtualHost *vhost,
+                        const std::string &pathTranslation,
+                        const std::string &sourceRoot);
   bool resolveURL(const VirtualHost *vhost,
                   const std::string &pathTranslation,
                   const std::string &sourceRoot);

hphp/test/server/http/server_root/global_document.php

@@ -0,0 +1,13 @@
+<?hh
+
+<<__EntryPoint>>
+function main_global_document() {
+  // Make the test runner happy. It expects this endpoint to exist.
+  if ($_SERVER['REQUEST_URI'] == '/hello.php') {
+    $testid = getenv('TESTID');
+    echo "Hello, World!{$testid}";
+    return;
+  }
+
+  echo "Hit global document\n";
+}

hphp/test/server/http/server_root/global_document_should_not_be_hit.php

@@ -0,0 +1,6 @@
+<?hh
+
+<<__EntryPoint>>
+function main_global_document() {
+  echo "Should not hit this!\n";
+}

hphp/test/server/http/tests/globalDocumentTest.php

@@ -0,0 +1,51 @@
+<?hh
+
+require_once('test_base.inc');
+require_once('globalDocumentTestUtils.inc');
+
+echo "No global doc\n";
+
+requestAll(
+  varray[
+    "global_document_should_not_be_hit.php",
+  ],
+  "",
+);
+
+echo "Global doc, existing file\n";
+
+requestAll(
+  varray[
+    "global_document_should_not_be_hit.php",
+  ],
+  "-vServer.GlobalDocument=/global_document.php",
+);
+
+echo "Global doc, nonexistent file\n";
+
+requestAll(
+  varray[
+    "this_file_does_not_exist.php",
+    "foo/this_file_does_not_exist.php",
+    "foo/bar/this_file_does_not_exist.php",
+  ],
+  "-vServer.GlobalDocument=/global_document.php",
+);
+
+echo "Nonexistent global doc\n";
+
+runTestWith404HealthCheck(
+  function($serverPort) {
+    $nonexistent_requests = varray[
+      "some_file.php",
+      "this_file_does_not_exist.php",
+      "index.php",
+    ];
+
+    foreach ($nonexistent_requests as $request) {
+      echo "Requesting '$request'\n";
+      var_dump(request('localhost', $serverPort, $request));
+    }
+  },
+  "-vServer.GlobalDocument=/this_file_does_not_exist.php",
+);

hphp/test/server/http/tests/globalDocumentTest.php.expectf

@@ -0,0 +1,20 @@
+No global doc
+Requesting 'global_document_should_not_be_hit.php'
+string(20) "Should not hit this!"
+Global doc, existing file
+Requesting 'global_document_should_not_be_hit.php'
+string(19) "Hit global document"
+Global doc, nonexistent file
+Requesting 'this_file_does_not_exist.php'
+string(19) "Hit global document"
+Requesting 'foo/this_file_does_not_exist.php'
+string(19) "Hit global document"
+Requesting 'foo/bar/this_file_does_not_exist.php'
+string(19) "Hit global document"
+Nonexistent global doc
+Requesting 'some_file.php'
+string(18) "404 File Not Found"
+Requesting 'this_file_does_not_exist.php'
+string(18) "404 File Not Found"
+Requesting 'index.php'
+string(18) "404 File Not Found"

hphp/test/server/http/tests/globalDocumentTestUtils.inc

@@ -0,0 +1,20 @@
+<?hh
+
+function runTestWith404HealthCheck($testController, $customArgs = '', $repoArgs = '',
+                                   $expect404 = false) {
+  $pid = posix_getpid();
+  try {
+    $serverProc = $serverPort = $adminPort = null;
+    $debugPort = false;
+    $serverProc = startServer(&$serverPort, &$adminPort, &$debugPort,
+                              __DIR__.'/..', __DIR__.'/../server_root',
+                              $customArgs, null, $repoArgs, true);
+    $testController($serverPort);
+    stopServer($adminPort, $serverProc);
+  } catch (Exception $e) {
+    error_log("Caught exception, test failed, pid=$pid, exn=".$e->getMessage());
+    killChildren($pid);
+    if ($serverProc) proc_close($serverProc);
+    error_log('test failed');
+  }
+}