Add support for upstream auth with ENV variables

CHANGELOG.md

@@ -1,3 +1,7 @@
+## Unreleased
+
+- Add support for upstream auth with ENV variables ([#339](https://github.com/rubygems/gemstash/pull/339), [@CiTroNaK](https://github.com/CiTroNaK))
+
 ## 2.4.0 (2023-09-27)
 
 ### Changes

docs/gemstash-multiple-sources.7.md

@@ -49,6 +49,10 @@ gem "rubywarrior"
 source "http://localhost:9292/upstream/#{CGI.escape("https://my.gem-source.local")}" do
   gem "my-gem"
 end
+
+source "http://localhost:9292/upstream/my-other.gem-source.local" do
+  gem "my-other-gem"
+end
 ```
 
 Notice the `CGI.escape` call in the second source. This is important, as
@@ -57,6 +61,54 @@ you want. The `/upstream` prefix tells Gemstash to use a gem source
 other than the default source. You can now bundle with the additional
 source.
 
+Notice that the third source doesn't need to be escaped.
+This is because the `https://` is used by default when no scheme is set,
+and the source URL does not contain any chars that need to be escaped.
+
+## Authentication with Multiple Sources
+
+You can use basic authentication or API keys on sources directly in Gemfile
+or using ENV variables on the Gemstash instance.
+
+Example `Gemfile`:
+```ruby
+# ./Gemfile
+require "cgi"
+source "http://localhost:9292"
+
+source "http://localhost:9292/upstream/#{CGI.escape("user:password@my.gem-source.local")}" do
+  gem "my-gem"
+end
+
+source "http://localhost:9292/upstream/#{CGI.escape("api_key@my-other.gem-source.local")}" do
+  gem "my-other-gem"
+end
+```
+
+If you set `GEMSTASH_<HOST>` ENV variable with your authentication information,
+you can omit it from the `Gemfile`:
+
+```ruby
+# ./Gemfile
+source "http://localhost:9292"
+
+source "http://localhost:9292/upstream/my.gem-source.local" do
+  gem "my-gem"
+end
+```
+
+And run the Gemstash with the credentials set in an ENV variable:
+
+```bash
+GEMSTASH_MY__GEM___SOURCE__LOCAL=user:password gemstash start --no-daemonize --config-file config.yml.erb
+```
+
+The name of the ENV variable is the uppercase version of the host name,
+with all `.` characters replaced with `__`, all `-` with `___` and a `GEMSTASH_` prefix 
+(it uses the same syntax as [Bundler](https://bundler.io/v2.4/man/bundle-config.1.html#CREDENTIALS-FOR-GEM-SOURCES)).
+
+Example: `my.gem-source.local` => `GEMSTASH_MY__GEM___SOURCE__LOCAL`
+
 ## Redirecting
 
 Gemstash supports an alternate mode of specifying your gem sources. If

lib/gemstash/upstream.rb

@@ -11,10 +11,12 @@ class Upstream
 
     attr_reader :user_agent, :uri
 
-    def_delegators :@uri, :scheme, :host, :user, :password, :to_s
+    def_delegators :@uri, :scheme, :host, :to_s
 
     def initialize(upstream, user_agent: nil)
-      @uri = URI(CGI.unescape(upstream.to_s))
+      url = CGI.unescape(upstream.to_s)
+      url = "https://#{url}" unless %r{^https?://}.match?(url)
+      @uri = URI(url)
       @user_agent = user_agent
       raise "URL '#{@uri}' is not valid!" unless @uri.to_s&.match?(URI::DEFAULT_PARSER.make_regexp)
     end
@@ -40,12 +42,41 @@ def host_id
       @host_id ||= "#{host}_#{hash}"
     end
 
+    def user
+      env_auth_user || @uri.user
+    end
+
+    def password
+      env_auth_pass || @uri.password
+    end
+
   private
 
     def hash
       Digest::MD5.hexdigest(to_s)
     end
 
+    def env_auth_user
+      return unless env_auth
+
+      env_auth.split(":", 2).first
+    end
+
+    def env_auth_pass
+      return unless env_auth
+      return unless env_auth.include?(":")
+
+      env_auth.split(":", 2).last
+    end
+
+    def env_auth
+      @env_auth ||= ENV["GEMSTASH_#{host_for_env}"]
+    end
+
+    def host_for_env
+      host.upcase.gsub(".", "__").gsub("-", "___")
+    end
+
     # :nodoc:
     class GemName
       def initialize(upstream, gem_name)

spec/gemstash/http_client_spec.rb

@@ -29,12 +29,34 @@
       it { is_expected.to include("Authorization" => "Basic dXNlcm5hbWU6cGFzc3dvcmQ=") }
     end
 
+    context "when user:pass auth is set by ENV variable" do
+      before do
+        allow(ENV).to receive(:[]).and_call_original
+        allow(ENV).to receive(:[]).with("GEMSTASH_LOCALHOST").and_return("username:password")
+      end
+
+      let(:upstream) { Gemstash::Upstream.new("https://localhost/") }
+      subject { Gemstash::HTTPClient.for(upstream).client.headers }
+      it { is_expected.to include("Authorization" => "Basic dXNlcm5hbWU6cGFzc3dvcmQ=") }
+    end
+
     context "when api_key auth is in the upstream url" do
       let(:upstream) { Gemstash::Upstream.new("https://api_key@localhost/") }
       subject { Gemstash::HTTPClient.for(upstream).client.headers }
       it { is_expected.to include("Authorization" => "Basic YXBpX2tleTo=") }
     end
 
+    context "when api_key auth is set by ENV variable" do
+      before do
+        allow(ENV).to receive(:[]).and_call_original
+        allow(ENV).to receive(:[]).with("GEMSTASH_LOCALHOST").and_return("api_key")
+      end
+
+      let(:upstream) { Gemstash::Upstream.new("https://localhost/") }
+      subject { Gemstash::HTTPClient.for(upstream).client.headers }
+      it { is_expected.to include("Authorization" => "Basic YXBpX2tleTo=") }
+    end
+
     context "when no auth is included in the upstream url" do
       let(:upstream) { Gemstash::Upstream.new("https://localhost/") }
       subject { Gemstash::HTTPClient.for(upstream).client.headers }

spec/gemstash/upstream_spec.rb

@@ -23,6 +23,16 @@
     expect(upstream_uri.password).to be_nil
   end
 
+  it "uses HTTPS schema by default" do
+    upstream_uri = Gemstash::Upstream.new("rubygems.org")
+    expect(upstream_uri.to_s).to eq("https://rubygems.org")
+    expect(upstream_uri.host).to eq("rubygems.org")
+    expect(upstream_uri.scheme).to eq("https")
+    expect(upstream_uri.url("gems")).to eq("https://rubygems.org/gems")
+    expect(upstream_uri.user).to be_nil
+    expect(upstream_uri.password).to be_nil
+  end
+
   it "supports user:pass url auth in the uri" do
     upstream_uri = Gemstash::Upstream.new("https://myuser:mypassword@rubygems.org/")
     expect(upstream_uri.user).to eq("myuser")
@@ -55,19 +65,43 @@
     expect(upstream_uri.url("gems", "key=value")).to eq("https://rubygems.org/gems?key=value")
   end
 
-  it "fails if the uri is not valid" do
-    expect { Gemstash::Upstream.new("something_that_is_not_an_uri") }.to raise_error(
-      /URL 'something_that_is_not_an_uri' is not valid/
-    )
-  end
-
   it "has a nil user agent if not provided" do
     expect(Gemstash::Upstream.new("https://rubygems.org/").user_agent).to be_nil
   end
 
   it "supports getting user agent" do
     expect(Gemstash::Upstream.new("https://rubygems.org/",
-                                  user_agent: "my_user_agent").user_agent).to eq("my_user_agent")
+      user_agent: "my_user_agent").user_agent).to eq("my_user_agent")
+  end
+
+  context "with ENV variables for upstream authentication" do
+    context "with user and password" do
+      before do
+        allow(ENV).to receive(:[]).and_call_original
+        allow(ENV).to receive(:[]).with("GEMSTASH_RUBYGEMS__ORG").and_return("myuser:mypassword")
+      end
+
+      it "users user:pass for auth" do
+        upstream_uri = Gemstash::Upstream.new("https://rubygems.org/")
+        expect(upstream_uri.user).to eq("myuser")
+        expect(upstream_uri.password).to eq("mypassword")
+        expect(upstream_uri.auth?).to be_truthy
+      end
+    end
+
+    context "with api key" do
+      before do
+        allow(ENV).to receive(:[]).and_call_original
+        allow(ENV).to receive(:[]).with("GEMSTASH_RUBYGEMS__ORG").and_return("api_key")
+      end
+
+      it "uses api_key for auth" do
+        upstream_uri = Gemstash::Upstream.new("https://rubygems.org/")
+        expect(upstream_uri.user).to eq("api_key")
+        expect(upstream_uri.password).to be_nil
+        expect(upstream_uri.auth?).to be_truthy
+      end
+    end
   end
 
   describe ".url" do