Install resolved packages

Author: ysbaddaden

src/manager.cr

@@ -30,6 +30,10 @@ module Shards
       resolver.spec(version)
     end
 
+    def install
+      resolver.install(version)
+    end
+
     private def resolver
       @resolver ||= Shards.find_resolver(@dependency)
     end

src/resolvers.cr

@@ -13,6 +13,27 @@ module Shards
 
     abstract def read_spec(version = nil)
     abstract def available_versions
+
+    protected def install_path
+      File.join(INSTALL_PATH, dependency.name)
+    end
+
+    protected def cleanup_install_directory
+      if File.exists?(install_path)
+        Shards.logger.debug "rm -rf #{escape install_path}"
+
+        if Dir.exists?(install_path)
+          #FileUtils.rm_rf(install_path)
+          system("rm -rf #{escape install_path}")
+        else
+          File.delete(install_path)
+        end
+      end
+    end
+
+    protected def escape(arg)
+      "'#{arg.gsub(/'/, "\\'")}'"
+    end
   end
 
   @@resolver_classes = {} of String => Resolver.class

src/resolvers/git.cr

@@ -3,15 +3,7 @@ module Shards
 
   class GitResolver < Resolver
     def read_spec(version = "*")
-      refs = case version
-      when RELEASE_VERSION
-        "v#{version}"
-      when "*"
-        "HEAD"
-      else
-        version
-      end
-
+      refs = git_refs(version)
       update_local_cache
 
       if file_exists?(refs, SPEC_FILENAME)
@@ -36,6 +28,17 @@ module Shards
       end
     end
 
+    # OPTIMIZE: don't clean/install if the installed version is the expected one (ie. don't be dumb!)
+    def install(version = nil)
+      refs = git_refs(version)
+      Shards.logger.info "Installing #{dependency.name} (#{version})"
+
+      cleanup_install_directory
+      Dir.mkdir(install_path)
+
+      run "git archive --format=tar #{refs} | tar x -C #{escape install_path}"
+    end
+
     def local_path
       File.join(CACHE_DIRECTORY, dependency.name)
     end
@@ -44,6 +47,17 @@ module Shards
       dependency["git"].to_s
     end
 
+    private def git_refs(version)
+      case version
+      when RELEASE_VERSION
+        "v#{version}"
+      when "*"
+        "HEAD"
+      else
+        version
+      end
+    end
+
     private def update_local_cache
       return if @updated_cache
       Shards.logger.info "Updating #{git_url}"
@@ -58,7 +72,7 @@ module Shards
     end
 
     private def clone_repository
-      run "git clone --mirror --quiet -- '#{git_url.gsub(/'/, "\\'")}' #{dependency.name}",
+      run "git clone --mirror --quiet -- #{escape git_url} #{dependency.name}",
         path: File.dirname(local_path)
     rescue Error
       raise Error.new("Failed to clone #{git_url}")

src/resolvers/path.cr

@@ -1,3 +1,15 @@
+lib LibC
+  fun symlink(old_path : UInt8*, new_path : UInt8*) : Int32
+end
+
+class File
+  def self.symlink(old_path, new_path)
+    ret = LibC.symlink(old_path, new_path)
+    raise Errno.new("Error creating symlink from #{old_path} to #{new_path}") if ret == 0
+    ret
+  end
+end
+
 module Shards
   class PathResolver < Resolver
     def read_spec(version = nil)
@@ -11,6 +23,12 @@ module Shards
     def local_path
       dependency["path"].to_s
     end
+
+    def install(version = nil)
+      Shards.logger.info "Using #{dependency.name} (#{local_path})"
+      cleanup_install_directory
+      File.symlink(local_path, install_path)
+    end
   end
 
   register_resolver :path, PathResolver

src/shards.cr

@@ -1,10 +1,11 @@
 module Shards
   SPEC_FILENAME = "shard.yml"
+
   CACHE_DIRECTORY = File.join(Dir.working_directory, ".shards")
+  Dir.mkdir(CACHE_DIRECTORY) unless Dir.exists?(CACHE_DIRECTORY)
 
-  unless Dir.exists?(CACHE_DIRECTORY)
-    Dir.mkdir(CACHE_DIRECTORY)
-  end
+  INSTALL_PATH = File.join(Dir.working_directory, "libs")
+  Dir.mkdir(INSTALL_PATH) unless Dir.exists?(INSTALL_PATH)
 end
 
 require "./logger"
@@ -16,11 +17,7 @@ begin
   spec = Shards::Spec.from_file(Dir.working_directory)
   manager = Shards::Manager.new(spec)
   manager.resolve
-
-  # TODO: install packages into the libs/ folder
-  manager.packages.each do |package|
-    p [package.name, package.version]
-  end
+  manager.packages.each(&.install)
 rescue ex : Shards::Error
   Shards.logger.error ex.message
   exit -1