- Split generator function

- Add hg dependency support
- Add example case

README.md

@@ -29,11 +29,102 @@ including its dependencies:
 
     $ nix-build
 
+An example use case scenario
+============================
+We can use `composer2nix` to automate the deployment of a web application as
+part of a NixOS configuration.
+
+For example, we can create the following trivial PHP web application
+(`index.php`) that uses the [dompdf](http://dompdf.github.io/) library to
+generate a PDF file from an HTML page:
+
+```php
+<?php
+require 'vendor/autoload.php';
+
+use Dompdf\Dompdf;
+
+$dompdf = new Dompdf();
+$dompdf->loadHtml('hello world');
+
+$dompdf->setPaper('A4', 'landscape');
+$dompdf->render();
+
+$dompdf->stream();
+?>
+```
+
+We can write the following `composer.json` configuration file to configure the
+`dompdf` dependency:
+
+```json
+{
+    "name": "exampleapp/exampleapp",
+
+    "require": {
+        "dompdf/dompdf": "^0.8.0"
+    }
+}
+```
+
+With the following commmand we can let `composer` deploy the dependencies (and
+pinpoint the used versions in a `composer.lock` file):
+
+    $ composer install
+
+Instead, we can also use `composer2nix`:
+
+    $ composer2nix
+
+The above command generates Nix expressions that can be used to deploy the web
+application and its dependencies.
+
+We can use Nix to build a bundle of our web application including its
+dependencies:
+
+$ nix-build
+$ ls result/
+index.php  vendor/
+
+(As may be observed, the `vendor/` folder contains all dependency artifacts).
+
+We can attach the generated package to a document root of the Apache server in
+a NixOS configuration:
+
+```nix
+{pkgs, config, ...}:
+
+let
+  myexampleapp = import /home/sander/myexampleapp {
+    inherit pkgs;
+  };
+in
+{
+  services.httpd = {
+    enable = true;
+    adminAddr = "admin@localhost";
+    extraModules = [
+      { name = "php7"; path = "${pkgs.php}/modules/libphp7.so"; }
+    ];
+    documentRoot = myexampleapp;
+  };
+
+  ...
+}
+```
+
+We can deploy the above NixOS configuration as follows:
+
+    $ nixos-rebuild switch
+
+If the above command succeeds, we have a running system with the Apache
+webserver serving our web application.
+
 Limitations
 ===========
 Currently, the state of this tool is that it is just a proof on concept
 implementation. As a result, it is lacking many features and probably buggy.
-Most importantly, only the `zip` and `git` dependencies are supported.
+Most importantly, only the `zip`, `git`, and `hg` dependencies are supported.
 
 License
 =======

bin/composer2nix

@@ -25,6 +25,7 @@ Options:
                          packages (defaults to: composer-env.nix)
      --prefer-source     Forces installation from package sources when possible
      --prefer-dist       Forces installation from package dist
+     --no-dev            Do not install the development packages
      --name              Name of the generated package (defaults to the name
                          provided in the composer.json file)
      --no-copy-composer-env
@@ -51,6 +52,7 @@ $options = getopt("hv", array(
 	"composer-env:",
 	"prefer-source",
 	"prefer-dist",
+	"no-dev",
 	"name:",
 	"no-copy-composer-env",
 	"help",
@@ -105,13 +107,18 @@ else
 
 $noCopyComposerEnv = array_key_exists("no-copy-composer-env", $options);
 
-$installType = "dist"; // TODO: consult composer.json's preferred-install property. defaults to: auto
+$preferredInstall = "dist"; // TODO: consult composer.json's preferred-install property. defaults to: auto
 
 if(array_key_exists("prefer-source", $options))
-	$installType = "source";
+	$preferredInstall = "source";
 
 if(array_key_exists("prefer-dist", $options))
-	$installType = "dist";
+	$preferredInstall = "dist";
+
+if(array_key_exists("no-dev", $options))
+	$noDev = true;
+else
+	$noDev = false;
 
 if(array_key_exists("name", $options))
 	$name = $options["name"];
@@ -122,7 +129,7 @@ else
 
 try
 {
-	Generator::generateNixExpressions($name, $installType, $configFile, $lockFile, $outputFile, $compositionFile, $composerEnvFile, $noCopyComposerEnv);
+	Generator::generateNixExpressions($name, $preferredInstall, $noDev, $configFile, $lockFile, $outputFile, $compositionFile, $composerEnvFile, $noCopyComposerEnv);
 }
 catch(Exception $ex)
 {

composer.json

@@ -4,15 +4,15 @@
   "type": "library",
   "license": "MIT",
   "authors": [
-    {
+      {
-      "name": "Sander van der Burg",
+          "name": "Sander van der Burg",
-      "email": "svanderburg@gmail.com",
+          "email": "svanderburg@gmail.com",
-      "homepage": "http://sandervanderburg.nl"
+          "homepage": "http://sandervanderburg.nl"
-    }
+      }
   ],
   
   "autoload": {
-    "psr-4": { "Composer2Nix\\": "src/Composer2Nix" }
+      "psr-4": { "Composer2Nix\\": "src/Composer2Nix" }
   },
 
   "bin": [ "bin/composer2nix" ]

src/Composer2Nix/Generator.php

@@ -4,7 +4,125 @@ use Exception;
 
 class Generator
 {
-	function generateNixExpressions($name, $installType, $configFile, $lockFile, $outputFile, $compositionFile, $composerEnvFile, $noCopyComposerEnv)
+	private static function composeNixFilePath($path)
+	{
+		if((strlen($path) > 0 && substr($path, 0, 1) === "/") || (strlen($path) > 1 && substr($path, 0, 2) === "./"))
+			return $path;
+		else
+			return "./".$path;
+	}
+
+	private static function selectSourceObject($preferredInstall, $package)
+	{
+		if($preferredInstall === "source")
+		{
+			// Use the source unless no source has been provided
+			if(array_key_exists("source", $package))
+				return $package["source"];
+			else if(array_key_exists("dist", $package))
+				return $package["dist"];
+			else
+				throw new Exception("Encountered a dangling package reference");
+		}
+		else
+		{
+			if(array_key_exists("dist", $package))
+				return $package["dist"];
+			else
+				throw new Exception("Encountered a dangling package reference");
+		}
+	}
+
+	private static function generatePackagesExpression($outputFile, $name, $preferredInstall, array $packages)
+	{
+		$handle = fopen($outputFile, "w");
+
+		if($handle === false)
+			throw new Exception("Cannot write to: ".$outputFile);
+
+		fwrite($handle, "{composerEnv, fetchgit ? null}:\n\n");
+		fwrite($handle, "let\n");
+		fwrite($handle, "  dependencies = {\n");
+
+		foreach($packages as $package)
+		{
+			$sourceObj = Generator::selectSourceObject($preferredInstall, $package);
+
+			switch($sourceObj["type"])
+			{
+				case "zip":
+					$hash = shell_exec('nix-prefetch-url "'.$sourceObj['url'].'"');
+					fwrite($handle, '    "'.$package["name"].'" = composerEnv.buildZipPackage {'."\n");
+					fwrite($handle, '      name = "'.strtr($package["name"], "/", "-").'-'.$sourceObj["reference"].'";'."\n");
+					fwrite($handle, '      url = "'.$sourceObj["url"].'";'."\n");
+					fwrite($handle, '      sha256 = "'.substr($hash, 0, -1).'";'."\n");
+					break;
+				case "git":
+					$outputStr = shell_exec('nix-prefetch-git "'.$sourceObj['url'].'" '.$sourceObj["reference"]);
+
+					$output = json_decode($outputStr, true);
+					$hash = $output["sha256"];
+
+					fwrite($handle, '    "'.$package["name"].'" = fetchgit {'."\n");
+					fwrite($handle, '      name = "'.strtr($package["name"], "/", "-").'-'.$sourceObj["reference"].'";'."\n");
+					fwrite($handle, '      url = "'.$sourceObj["url"].'";'."\n");
+					fwrite($handle, '      rev = "'.$sourceObj["reference"].'";'."\n");
+					fwrite($handle, '      sha256 = "'.$hash.'";'."\n");
+					break;
+				case "hg":
+					$outputStr = shell_exec('nix-prefetch-hg "'.$sourceObj['url'].'" '.$sourceObj["reference"]);
+
+					$output = json_decode($outputStr, true);
+					$hash = $output["sha256"];
+
+					fwrite($handle, '    "'.$package["name"].'" = fetchhg {'."\n");
+					fwrite($handle, '      name = "'.strtr($package["name"], "/", "-").'-'.$sourceObj["reference"].'";'."\n");
+					fwrite($handle, '      url = "'.$sourceObj["url"].'";'."\n");
+					fwrite($handle, '      rev = "'.$sourceObj["reference"].'";'."\n");
+					fwrite($handle, '      sha256 = "'.$hash.'";'."\n");
+				default:
+					throw new Exception("Cannot convert dependency of type: ".$sourceObj["type"]);
+			}
+
+			fwrite($handle, "    };\n");
+		}
+
+		fwrite($handle, "  };\n");
+		fwrite($handle, "in\n");
+		fwrite($handle, "composerEnv.buildPackage {\n");
+		fwrite($handle, '  name = "'.$name.'";'."\n");
+		fwrite($handle, "  src = ./.;\n");
+		fwrite($handle, "  inherit dependencies;\n");
+		fwrite($handle, "}\n");
+
+		fclose($handle);
+	}
+
+	private static function generateCompositionExpression($compositionFile, $outputFile, $composerEnvFile)
+	{
+		$handle = fopen($compositionFile, "w");
+
+		if($handle === false)
+			throw new Exception("Cannot write to: ".$compositionFile);
+
+		fwrite($handle, "{ pkgs ? import <nixpkgs> { inherit system; }\n");
+		fwrite($handle, ", system ? builtins.currentSystem\n");
+		fwrite($handle, "}:\n\n");
+
+		fwrite($handle, "let\n");
+		fwrite($handle, "  composerEnv = import ".Generator::composeNixFilePath($composerEnvFile)." {\n");
+		fwrite($handle, "    inherit (pkgs) stdenv writeTextFile fetchurl php unzip;\n");
+		fwrite($handle, "  };\n");
+		fwrite($handle, "in\n");
+		fwrite($handle, "import ".Generator::composeNixFilePath($outputFile)." {\n");
+		fwrite($handle, "  inherit composerEnv;\n");
+		fwrite($handle, "  inherit (pkgs) fetchgit;\n");
+		fwrite($handle, "}\n");
+
+		fclose($handle);
+	}
+
+	public static function generateNixExpressions($name, $preferredInstall, $noDev, $configFile, $lockFile, $outputFile, $compositionFile, $composerEnvFile, $noCopyComposerEnv)
 	{
 		/* Open the composer.json file and decode it */
 		$composerJSONStr = file_get_contents($configFile);
@@ -38,103 +156,30 @@ class Generator
 				throw new Exception("Cannot open contents of: ".$lockFile);
 
 			$lockConfig = json_decode($composerLockStr, true);
+			
+			if(array_key_exists("packages", $lockConfig))
+				$packages = $lockConfig["packages"];
+			else
+				$packages = array();
+
+			if(!$noDev && array_key_exists("packages-dev", $lockConfig))
+			{
+				foreach($lockConfig["packages-dev"] as $identifier => $devPackage)
+					$packages[$identifier] = $devPackage;
+			}
 		}
 		else
-			$lockConfig = null;
+			$packages = array();
 
 		/* Generate packages expression */
-
+		Generator::generatePackagesExpression($outputFile, $name, $preferredInstall, $packages);
-		$handle = fopen($outputFile, "w");
-
-		if($handle === false)
-			throw new Exception("Cannot write to: ".$outputFile);
-
-		if($lockConfig === null)
-			$packages = array();
-		else
-			$packages = $lockConfig["packages"];
-
-		fwrite($handle, "{composerEnv, fetchgit ? null}:\n\n");
-		fwrite($handle, "let\n");
-		fwrite($handle, "  dependencies = {\n");
-
-		foreach($packages as $package)
-		{
-			$sourceObj = $package[$installType];
-
-			switch($sourceObj["type"])
-			{
-				case "zip":
-					$hash = shell_exec('nix-prefetch-url "'.$sourceObj['url'].'"');
-					fwrite($handle, '    "'.$package["name"].'" = composerEnv.buildZipPackage {'."\n");
-					fwrite($handle, '      name = "'.strtr($package["name"], "/", "-").'-'.$sourceObj["reference"].'";'."\n");
-					fwrite($handle, '      url = "'.$sourceObj["url"].'";'."\n");
-					fwrite($handle, '      sha256 = "'.substr($hash, 0, -1).'";'."\n");
-					break;
-				case "git":
-					$outputStr = shell_exec('nix-prefetch-git "'.$sourceObj['url'].'" '.$sourceObj["reference"]);
-
-					$output = json_decode($outputStr, true);
-					$hash = $output["sha256"];
-
-					fwrite($handle, '    "'.$package["name"].'" = fetchgit {'."\n");
-					fwrite($handle, '      name = "'.strtr($package["name"], "/", "-").'-'.$sourceObj["reference"].'";'."\n");
-					fwrite($handle, '      url = "'.$sourceObj["url"].'";'."\n");
-					fwrite($handle, '      rev = "'.$sourceObj["reference"].'";'."\n");
-					fwrite($handle, '      sha256 = "'.$hash.'";'."\n");
-					break;
-				default:
-					throw new Exception("Cannot convert dependency of type: ".$sourceObj["type"]);
-			}
-
-			fwrite($handle, "    };\n");
-		}
-
-		fwrite($handle, "  };\n");
-		fwrite($handle, "in\n");
-		fwrite($handle, "composerEnv.buildPackage {\n");
-		fwrite($handle, '  name = "'.$name.'";'."\n");
-		fwrite($handle, "  src = ./.;\n");
-		fwrite($handle, "  inherit dependencies;\n");
-		fwrite($handle, "}\n");
-
-		fclose($handle);
 
 		/* Generate composition expression */
-
+		Generator::generateCompositionExpression($compositionFile, $outputFile, $composerEnvFile);
-		$handle = fopen($compositionFile, "w");
-
-		if($handle === false)
-			throw new Exception("Cannot write to: ".$compositionFile);
-
-		function composeNixFilePath($path)
-		{
-			if((strlen($path) > 0 && substr($path, 0, 1) === "/") || (strlen($path) > 1 && substr($path, 0, 2) === "./"))
-				return $path;
-			else
-				return "./".$path;
-		}
-
-		fwrite($handle, "{ pkgs ? import <nixpkgs> { inherit system; }\n");
-		fwrite($handle, ", system ? builtins.currentSystem\n");
-		fwrite($handle, "}:\n\n");
-
-		fwrite($handle, "let\n");
-		fwrite($handle, "  composerEnv = import ".composeNixFilePath($composerEnvFile)." {\n");
-		fwrite($handle, "    inherit (pkgs) stdenv writeTextFile fetchurl php unzip;\n");
-		fwrite($handle, "  };\n");
-		fwrite($handle, "in\n");
-		fwrite($handle, "import ".composeNixFilePath($outputFile)." {\n");
-		fwrite($handle, "  inherit composerEnv;\n");
-		fwrite($handle, "  inherit (pkgs) fetchgit;\n");
-		fwrite($handle, "}\n");
-
-		fclose($handle);
 
 		/* Copy composer-env.nix */
-
 		if(!$noCopyComposerEnv && !copy(dirname(__FILE__)."/composer-env.nix", $composerEnvFile))
-			throw new Exception("Cannot copy node-env.nix!");
+			throw new Exception("Cannot copy composer-env.nix!");
 	}
 }
 ?>

src/Composer2Nix/composer-env.nix

@@ -64,7 +64,7 @@ rec {
 
           if($composerLockStr === false)
           {
-              print("Cannot open composer.lock contents");
+              fwrite(STDERR, "Cannot open composer.lock contents\n");
               exit(1);
           }
           else