add env + config for package + settings locations

fix #229

changelog/dpath.dd

@@ -0,0 +1,41 @@
+DUB settings & packages directory placement overhauled
+
+You can now configure where DUB places its downloaded packages and where the user configuration is stored through environment variables or through the dub configuration. You need to use an environment variable or the system-wide dub configuration to specify where the user configuration is stored.
+
+By default DUB stores the packages on
+- Windows: `%APPDATA%/dub/settings.json` + `%LOCALAPPDATA%/dub/packages/`
+- Posix: `$HOME/.dub/{packages/,settings.json}`
+
+now if the `DUB_HOME` environment variable is set it instead stores the packages (and other config) in
+- `$DUB_HOME/{packages/,settings.json}`
+
+alternatively if `DUB_HOME` isn't set, but `DPATH` is set, the following path is used:
+- `$DPATH/dub/{packages/,settings.json}`
+
+The `DPATH` environment variable is intended to be used by all D tooling related things doing user-space installation of things. It can be used to avoid cluttering the home folder.
+
+Additionally to environment variables it is possible to configure the package placement path + settings.json path through DUB's settings.json file. To configure where the user-editable settings.json is placed you need to adjust the system-wide dub configuration.
+
+In the settings.json you can set the following fields:
+
+```json
+{
+    "dubHome": "/path/to/dub", // sets both package store and config location
+
+    // OR
+
+    "userSettings": "/path/to/dub/settings/folder",
+    "localRepository": "/path/to/dub/repository/folder"
+}
+```
+
+Additionally, these config paths will have environment variables using the `$VARIABLE` syntax resolved.
+
+The following list describes which path is going to be picked, from top to bottom, stopping whenever one is found:
+
+- `$DUB_HOME` environment variable
+- `$DPATH` environment variable
+- system-wide settings.json: `"userSettings"` property
+- system-wide settings.json: `"dubHome"` property (only for userSettings)
+- through all settings.json: `"localRepository"` property
+- through all settings.json: `"dubHome"` property (only for localRepository)

source/dub/dub.d

@@ -302,9 +302,120 @@ class Dub {
 		assert(dub.computePkgSuppliers(null, SkipPackageSuppliers.none, null).length == 1);
 		assert(dub.computePkgSuppliers(null, SkipPackageSuppliers.configured, null).length == 0);
 		assert(dub.computePkgSuppliers(null, SkipPackageSuppliers.standard, null).length == 0);
-
 		assert(dub.computePkgSuppliers(null, SkipPackageSuppliers.standard, "http://example.com/")
-               .length == 1);
+			.length == 1);
+
+		dub.m_config.skipRegistry = typeof(dub.m_config.skipRegistry)(SkipPackageSuppliers.configured);
+		assert(dub.getPackageSuppliers(null).length == 0);
+
+		dub.m_config.skipRegistry = typeof(dub.m_config.skipRegistry)(SkipPackageSuppliers.standard);
+		assert(dub.getPackageSuppliers(null).length == 0);
+
+		environment["DUB_REGISTRY"] = "http://example.com/";
+		assert(dub.getPackageSuppliers(null).length == 1);
+	}
+
+	/** Initializes the instance with a single package search path, without
+		loading a package.
+
+		This constructor corresponds to the "--bare" option of the command line
+		interface. Use
+	*/
+	this(NativePath override_path)
+	{
+		init(NativePath());
+		m_overrideSearchPath = override_path;
+		m_packageManager = new PackageManager(override_path);
+	}
+
+	private void loadConfigAndSetDirs(NativePath root_path)
+	{
+		import configy.Read;
+
+		this.m_dirs = SpecialDirs.make();
+
+		void readSettingsFile (NativePath path_)
+		{
+			const path = path_.toNativeString();
+			if (path.exists)
+				this.m_config = this.m_config.merge(
+					parseConfigFile!UserConfiguration(CLIArgs(path)));
+		}
+
+		const dubFolderPath = NativePath(thisExePath).parentPath;
+
+		// override default userSettings + localRepository if a $DPATH or
+		// $DUB_HOME environment variable is set.
+		bool overrideUserSettings;
+		bool overrideLocalRepository;
+		{
+			string dpathOverride = environment.get("DUB_HOME");
+			if (!dpathOverride.length) {
+				dpathOverride = environment.get("DPATH");
+				if (dpathOverride.length)
+					dpathOverride = (NativePath(dpathOverride) ~ "dub/").toNativeString();
+
+			}
+			if (dpathOverride.length) {
+				overrideUserSettings = true;
+				overrideLocalRepository = true;
+
+				m_dirs.userSettings = NativePath(dpathOverride);
+				m_dirs.localRepository = m_dirs.userSettings;
+			}
+		}
+
+		// load system-wide configs:
+		readSettingsFile(m_dirs.systemSettings ~ "settings.json");
+		readSettingsFile(dubFolderPath ~ "../etc/dub/settings.json");
+		version (Posix) {
+			if (dubFolderPath.absolute && dubFolderPath.startsWith(NativePath("usr")))
+				readSettingsFile(NativePath("/etc/dub/settings.json"));
+		}
+
+		// Override user + local package path from /etc/dub/settings.json
+		// Then continues loading local settings from these folders. (keeping
+		// global /etc/dub/settings.json settings intact)
+		//
+		// Don't use it if either $DPATH or $DUB_HOME are set.
+		if (!overrideUserSettings) {
+			if (this.userSettingsOverride.length) {
+				m_dirs.userSettings = NativePath(this.userSettingsOverride.expandEnvironmentVariables);
+
+				overrideUserSettings = true;
+			} else if (this.dubHome.length) {
+				m_dirs.userSettings = NativePath(this.dubHome.expandEnvironmentVariables);
+
+				overrideUserSettings = true;
+			}
+		}
+
+		// load user config:
+		readSettingsFile(m_dirs.userSettings ~ "settings.json");
+
+		// load per-package config:
+		if (!root_path.empty)
+			readSettingsFile(root_path ~ "dub.settings.json");
+
+		// resolve directories from config
+		if (!overrideLocalRepository) {
+			if (this.localRepository.length) {
+				m_dirs.localRepository = NativePath(this.localRepository.expandEnvironmentVariables);
+
+				overrideLocalRepository = true;
+			} else if (this.dubHome.length) {
+				m_dirs.localRepository = NativePath(this.dubHome.expandEnvironmentVariables);
+
+				overrideLocalRepository = true;
+			}
+		}
+	}
+
+	private void init(NativePath root_path)
+	{
+		loadConfigAndSetDirs(root_path);
+
+		determineDefaultCompiler();
 	}
 
 	@property bool dryRun() const { return m_dryRun; }
@@ -369,6 +480,10 @@ class Dub {
 	@property const(string[string]) defaultPreRunEnvironments() const { return this.m_config.defaultPreRunEnvironments; }
 	@property const(string[string]) defaultPostRunEnvironments() const { return this.m_config.defaultPostRunEnvironments; }
 
+	private @property const(string) dubHome() const { return this.m_config.dubHome; }
+	private @property const(string) userSettingsOverride() const { return this.m_config.userSettings; }
+	private @property const(string) localRepository() const { return this.m_config.localRepository; }
+
 	/** Loads the package that resides within the configured `rootPath`.
 	*/
 	void loadPackage()
@@ -1828,6 +1943,9 @@ private struct UserConfiguration {
 	SetInfo!(string[string]) defaultPostBuildEnvironments;
 	SetInfo!(string[string]) defaultPreRunEnvironments;
 	SetInfo!(string[string]) defaultPostRunEnvironments;
+	SetInfo!(string) dubHome;
+	SetInfo!(string) userSettings;
+	SetInfo!(string) localRepository;
 
 	/// Merge a lower priority config (`this`) with a `higher` priority config
 	public UserConfiguration merge(UserConfiguration higher)

source/dub/project.d

@@ -1433,6 +1433,7 @@ private string[] processVarsWithGlob(Project, Package)(string var, in Project pr
 		.filter!(name => globMatch(name, res))
 		.array;
 }
+
 /// Expand variables using `$VAR_NAME` or `${VAR_NAME}` syntax.
 /// `$$` escapes itself and is expanded to a single `$`.
 private string expandVars(alias expandVar)(string s)
@@ -1518,6 +1519,13 @@ unittest
 	assert(expandVars!expandVar("$${DUB_EXE:-dub}") == "${DUB_EXE:-dub}");
 }
 
+string expandEnvironmentVariables(string s)
+{
+	import std.process : environment;
+
+	return expandVars!(v => environment.get(v))(s);
+}
+
 // Keep the following list up-to-date if adding more build settings variables.
 /// List of variables that can be used in build settings
 package(dub) immutable buildSettingsVars = [

test/dpath-variable.sh

@@ -0,0 +1,11 @@
+#!/usr/bin/env bash
+
+. $(dirname "${BASH_SOURCE[0]}")/common.sh
+export DPATH="${CURR_DIR}/dpath-variable/dpath"
+rm -rf "$DPATH"
+cd ${CURR_DIR}/dpath-variable
+${DUB} upgrade
+
+if [[ ! -f "$DPATH/dub/packages/gitcompatibledubpackage-1.0.1/gitcompatibledubpackage/dub.json" ]]; then
+	die $LINENO 'Did not get dependencies installed into $DPATH.'
+fi

test/dpath-variable/.gitignore

@@ -0,0 +1 @@
+dpath

test/dpath-variable/dub.json

@@ -0,0 +1,6 @@
+{
+	"name": "dpath-variable",
+	"dependencies": {
+		"gitcompatibledubpackage": "1.0.1"
+	}
+}

test/dpath-variable/source/app.d

@@ -0,0 +1,3 @@
+void main()
+{
+}