Merge branch 'set-default-cache-key-for-jobs' into 'master'

Set default cache key to 'default' for jobs

Closes #22419

See merge request !9666

changelogs/unreleased/set-default-cache-key-for-jobs.yml

+---
+title: Set default cache key to "default" for jobs
+merge_request: 9666
+author:

doc/ci/yaml/README.md

@@ -166,10 +166,11 @@ which can be set in GitLab's UI.
 cached between jobs. You can only use paths that are within the project
 workspace.
 
-**By default the caching is enabled per-job and per-branch.**
+**By default caching is enabled and shared between pipelines and jobs,
+starting from GitLab 9.0**
 
-If `cache` is defined outside the scope of the jobs, it means it is set
-globally and all jobs will use its definition.
+If `cache` is defined outside the scope of jobs, it means it is set
+globally and all jobs will use that definition.
 
 Cache all files in `binaries` and `.config`:
 
@@ -202,7 +203,7 @@ rspec:
     - binaries/
 ```
 
-Locally defined cache overwrites globally defined options. The following `rspec`
+Locally defined cache overrides globally defined options. The following `rspec`
 job will cache only `binaries/`:
 
 ```yaml
@@ -213,10 +214,15 @@ cache:
 rspec:
   script: test
   cache:
+    key: rspec
     paths:
     - binaries/
 ```
 
+Note that since cache is shared between jobs, if you're using different
+paths for different jobs, you should also set a different **cache:key**
+otherwise cache content can be overwritten.
+
 The cache is provided on a best-effort basis, so don't expect that the cache
 will be always present. For implementation details, please check GitLab Runner.
 
@@ -233,6 +239,9 @@ different jobs or even different branches.
 
 The `cache:key` variable can use any of the [predefined variables](../variables/README.md).
 
+The default key is **default** across the project, therefore everything is
+shared between each pipelines and jobs by default, starting from GitLab 9.0.
+
 ---
 
 **Example configurations**

lib/gitlab/ci/config/entry/cache.rb

@@ -22,6 +22,12 @@ module Gitlab
 
           entry :paths, Entry::Paths,
             description: 'Specify which paths should be cached across builds.'
+
+          helpers :key
+
+          def value
+            super.merge(key: key_value)
+          end
         end
       end
     end

lib/gitlab/ci/config/entry/key.rb

@@ -11,6 +11,10 @@ module Gitlab
           validations do
             validates :config, key: true
           end
+
+          def self.default
+            'default'
+          end
         end
       end
     end

lib/gitlab/ci/config/entry/node.rb

@@ -70,6 +70,12 @@ module Gitlab
             true
           end
 
+          def inspect
+            val = leaf? ? config : descendants
+            unspecified = specified? ? '' : '(unspecified) '
+            "#<#{self.class.name} #{unspecified}{#{key}: #{val.inspect}}>"
+          end
+
           def self.default
           end
 

lib/gitlab/ci/config/entry/undefined.rb

@@ -29,6 +29,10 @@ module Gitlab
           def relevant?
             false
           end
+
+          def inspect
+            "#<#{self.class.name}>"
+          end
         end
       end
     end

spec/lib/gitlab/ci/config/entry/cache_spec.rb

@@ -24,6 +24,20 @@ describe Gitlab::Ci::Config::Entry::Cache do
           expect(entry).to be_valid
         end
       end
+
+      context 'when key is missing' do
+        let(:config) do
+          { untracked: true,
+            paths: ['some/path/'] }
+        end
+
+        describe '#value' do
+          it 'sets key with the default' do
+            expect(entry.value[:key])
+              .to eq(Gitlab::Ci::Config::Entry::Key.default)
+          end
+        end
+      end
     end
 
     context 'when entry value is not correct' do

spec/lib/gitlab/ci/config/entry/factory_spec.rb

@@ -60,13 +60,13 @@ describe Gitlab::Ci::Config::Entry::Factory do
     end
 
     context 'when creating entry with nil value' do
-      it 'creates an undefined entry' do
+      it 'creates an unspecified entry' do
         entry = factory
           .value(nil)
           .create!
 
         expect(entry)
-          .to be_an_instance_of Gitlab::Ci::Config::Entry::Unspecified
+          .not_to be_specified
       end
     end
 

spec/lib/gitlab/ci/config/entry/global_spec.rb

@@ -188,7 +188,7 @@ describe Gitlab::Ci::Config::Entry::Global do
 
         it 'contains unspecified nodes' do
           expect(global.descendants.first)
-            .to be_an_instance_of Gitlab::Ci::Config::Entry::Unspecified
+            .not_to be_specified
         end
       end
 

spec/lib/gitlab/ci/config/entry/key_spec.rb

@@ -31,4 +31,10 @@ describe Gitlab::Ci::Config::Entry::Key do
       end
     end
   end
+
+  describe '.default' do
+    it 'returns default key' do
+      expect(described_class.default).to eq 'default'
+    end
+  end
 end