Revert "Merge branch 'revert-satellites' into 'master' "

This reverts commit 5daf44b7c86e0e2641a902b1da8b01d91fa3dbfa, reversing
changes made to 2f706fbd231cabe7a76a5d17ac44285aaaf8592c.

16 files changed, 268 insertions, 199 deletions

diff --git a/app/services/base_service.rb b/app/services/base_service.rb
index 6d9ed345914..f00ec7408b6 100644
--- a/app/services/base_service.rb
+++ b/app/services/base_service.rb
@@ -31,6 +31,10 @@ class BaseService
     SystemHooksService.new
   end
 
+  def repository
+    project.repository
+  end
+
   # Add an error to the specified model for restricted visibility levels
   def deny_visibility_level(model, denied_visibility_level = nil)
     denied_visibility_level ||= model.visibility_level
diff --git a/app/services/compare_service.rb b/app/services/compare_service.rb
index 6aa9df4b194..70f642baaaa 100644
--- a/app/services/compare_service.rb
+++ b/app/services/compare_service.rb
@@ -1,27 +1,28 @@
+require 'securerandom'
+
 # Compare 2 branches for one repo or between repositories
 # and return Gitlab::CompareResult object that responds to commits and diffs
 class CompareService
-  def execute(current_user, source_project, source_branch, target_project, target_branch)
-    # Try to compare branches to get commits list and diffs
-    #
-    # Note: Use satellite only when need to compare between two repos
-    # because satellites are slower than operations on bare repo
-    if target_project == source_project
-      Gitlab::CompareResult.new(
-        Gitlab::Git::Compare.new(
-          target_project.repository.raw_repository,
-          target_branch,
-          source_branch,
-        )
+  def execute(source_project, source_branch, target_project, target_branch)
+    source_sha = source_project.commit(source_branch).sha
+
+    # If compare with other project we need to fetch ref first
+    unless target_project == source_project
+      random_string = SecureRandom.hex
+
+      target_project.repository.fetch_ref(
+        source_project.repository.path_to_repo,
+        "refs/heads/#{source_branch}",
+        "refs/tmp/#{random_string}/head"
       )
-    else
-      Gitlab::Satellite::CompareAction.new(
-        current_user,
-        target_project,
-        target_branch,
-        source_project,
-        source_branch
-      ).result
     end
+
+    Gitlab::CompareResult.new(
+      Gitlab::Git::Compare.new(
+        target_project.repository.raw_repository,
+        target_branch,
+        source_sha,
+      )
+    )
   end
 end
diff --git a/app/services/files/base_service.rb b/app/services/files/base_service.rb
index bd245100955..d7b40ee8906 100644
--- a/app/services/files/base_service.rb
+++ b/app/services/files/base_service.rb
@@ -1,17 +1,80 @@
 module Files
   class BaseService < ::BaseService
-    attr_reader :ref, :path
+    class ValidationError < StandardError; end
 
-    def initialize(project, user, params, ref, path = nil)
-      @project, @current_user, @params = project, user, params.dup
-      @ref = ref
-      @path = path
+    def execute
+      @current_branch = params[:current_branch]
+      @target_branch  = params[:target_branch]
+      @commit_message = params[:commit_message]
+      @file_path      = params[:file_path]
+      @file_content   = if params[:file_content_encoding] == 'base64'
+                          Base64.decode64(params[:file_content])
+                        else
+                          params[:file_content]
+                        end
+
+      # Validate parameters
+      validate
+
+      # Create new branch if it different from current_branch
+      if @target_branch != @current_branch
+        create_target_branch
+      end
+
+      if sha = commit
+        after_commit(sha, @target_branch)
+        success
+      else
+        error("Something went wrong. Your changes were not committed")
+      end
+    rescue ValidationError => ex
+      error(ex.message)
     end
 
     private
 
-    def repository
-      project.repository
+    def after_commit(sha, branch)
+      PostCommitService.new(project, current_user).execute(sha, branch)
+    end
+
+    def current_branch
+      @current_branch ||= params[:current_branch]
+    end
+
+    def target_branch
+      @target_branch ||= params[:target_branch]
+    end
+
+    def raise_error(message)
+      raise ValidationError.new(message)
+    end
+
+    def validate
+      allowed = ::Gitlab::GitAccess.new(current_user, project).can_push_to_branch?(@target_branch)
+
+      unless allowed
+        raise_error("You are not allowed to push into this branch")
+      end
+
+      unless project.empty_repo?
+        unless repository.branch_names.include?(@current_branch)
+          raise_error("You can only create files if you are on top of a branch")
+        end
+
+        if @current_branch != @target_branch
+          if repository.branch_names.include?(@target_branch)
+            raise_error("Branch with such name already exists. You need to switch to this branch in order to make changes")
+          end
+        end
+      end
+    end
+
+    def create_target_branch
+      result = CreateBranchService.new(project, current_user).execute(@target_branch, @current_branch)
+
+      unless result[:status] == :success
+        raise_error("Something went wrong when we tried to create #{@target_branch} for you")
+      end
     end
   end
 end
diff --git a/app/services/files/create_service.rb b/app/services/files/create_service.rb
index 23833aa78ec..91d715b2d63 100644
--- a/app/services/files/create_service.rb
+++ b/app/services/files/create_service.rb
@@ -1,52 +1,30 @@
 require_relative "base_service"
 
 module Files
-  class CreateService < BaseService
-    def execute
-      allowed = Gitlab::GitAccess.new(current_user, project).can_push_to_branch?(ref)
+  class CreateService < Files::BaseService
+    def commit
+      repository.commit_file(current_user, @file_path, @file_content, @commit_message, @target_branch)
+    end
 
-      unless allowed
-        return error("You are not allowed to create file in this branch")
-      end
+    def validate
+      super
 
-      file_name = File.basename(path)
-      file_path = path
+      file_name = File.basename(@file_path)
 
       unless file_name =~ Gitlab::Regex.file_name_regex
-        return error(
+        raise_error(
           'Your changes could not be committed, because the file name ' +
           Gitlab::Regex.file_name_regex_message
         )
       end
 
-      if project.empty_repo?
-        # everything is ok because repo does not have a commits yet
-      else
-        unless repository.branch_names.include?(ref)
-          return error("You can only create files if you are on top of a branch")
-        end
-
-        blob = repository.blob_at_branch(ref, file_path)
+      unless project.empty_repo?
+        blob = repository.blob_at_branch(@current_branch, @file_path)
 
         if blob
-          return error("Your changes could not be committed, because file with such name exists")
+          raise_error("Your changes could not be committed, because file with such name exists")
         end
       end
-
-
-      new_file_action = Gitlab::Satellite::NewFileAction.new(current_user, project, ref, file_path)
-      created_successfully = new_file_action.commit!(
-        params[:content],
-        params[:commit_message],
-        params[:encoding],
-        params[:new_branch]
-      )
-
-      if created_successfully
-        success
-      else
-        error("Your changes could not be committed, because the file has been changed")
-      end
     end
   end
 end
diff --git a/app/services/files/delete_service.rb b/app/services/files/delete_service.rb
index 1497a0f883b..27c881c3430 100644
--- a/app/services/files/delete_service.rb
+++ b/app/services/files/delete_service.rb
@@ -1,36 +1,9 @@
 require_relative "base_service"
 
 module Files
-  class DeleteService < BaseService
-    def execute
-      allowed = ::Gitlab::GitAccess.new(current_user, project).can_push_to_branch?(ref)
-
-      unless allowed
-        return error("You are not allowed to push into this branch")
-      end
-
-      unless repository.branch_names.include?(ref)
-        return error("You can only create files if you are on top of a branch")
-      end
-
-      blob = repository.blob_at_branch(ref, path)
-
-      unless blob
-        return error("You can only edit text files")
-      end
-
-      delete_file_action = Gitlab::Satellite::DeleteFileAction.new(current_user, project, ref, path)
-
-      deleted_successfully = delete_file_action.commit!(
-        nil,
-        params[:commit_message]
-      )
-
-      if deleted_successfully
-        success
-      else
-        error("Your changes could not be committed, because the file has been changed")
-      end
+  class DeleteService < Files::BaseService
+    def commit
+      repository.remove_file(current_user, @file_path, @commit_message, @target_branch)
     end
   end
 end
diff --git a/app/services/files/update_service.rb b/app/services/files/update_service.rb
index 0724d3ae634..a20903c6f02 100644
--- a/app/services/files/update_service.rb
+++ b/app/services/files/update_service.rb
@@ -1,39 +1,9 @@
 require_relative "base_service"
 
 module Files
-  class UpdateService < BaseService
-    def execute
-      allowed = ::Gitlab::GitAccess.new(current_user, project).can_push_to_branch?(ref)
-
-      unless allowed
-        return error("You are not allowed to push into this branch")
-      end
-
-      unless repository.branch_names.include?(ref)
-        return error("You can only create files if you are on top of a branch")
-      end
-
-      blob = repository.blob_at_branch(ref, path)
-
-      unless blob
-        return error("You can only edit text files")
-      end
-
-      edit_file_action = Gitlab::Satellite::EditFileAction.new(current_user, project, ref, path)
-      edit_file_action.commit!(
-        params[:content],
-        params[:commit_message],
-        params[:encoding],
-        params[:new_branch]
-      )
-
-      success
-    rescue Gitlab::Satellite::CheckoutFailed => ex
-      error("Your changes could not be committed because ref '#{ref}' could not be checked out", 400)
-    rescue Gitlab::Satellite::CommitFailed => ex
-      error("Your changes could not be committed. Maybe there was nothing to commit?", 409)
-    rescue Gitlab::Satellite::PushFailed => ex
-      error("Your changes could not be committed. Maybe the file was changed by another process?", 409)
+  class UpdateService < Files::BaseService
+    def commit
+      repository.commit_file(current_user, @file_path, @file_content, @commit_message, @target_branch)
     end
   end
 end
diff --git a/app/services/git_push_service.rb b/app/services/git_push_service.rb
index 5a2c97b08af..81535450ac1 100644
--- a/app/services/git_push_service.rb
+++ b/app/services/git_push_service.rb
@@ -10,16 +10,14 @@ class GitPushService
   #
   # Next, this method:
   #  1. Creates the push event
-  #  2. Ensures that the project satellite exists
-  #  3. Updates merge requests
-  #  4. Recognizes cross-references from commit messages
-  #  5. Executes the project's web hooks
-  #  6. Executes the project's services
+  #  2. Updates merge requests
+  #  3. Recognizes cross-references from commit messages
+  #  4. Executes the project's web hooks
+  #  5. Executes the project's services
   #
   def execute(project, user, oldrev, newrev, ref)
     @project, @user = project, user
 
-    project.ensure_satellite_exists
     project.repository.expire_cache
 
     if push_remove_branch?(ref, newrev)
@@ -133,7 +131,8 @@ class GitPushService
   end
 
   def is_default_branch?(ref)
-    Gitlab::Git.branch_ref?(ref) && Gitlab::Git.ref_name(ref) == project.default_branch
+    Gitlab::Git.branch_ref?(ref) &&
+      (Gitlab::Git.ref_name(ref) == project.default_branch || project.default_branch.nil?)
   end
 
   def commit_user(commit)
diff --git a/app/services/merge_requests/auto_merge_service.rb b/app/services/merge_requests/auto_merge_service.rb
deleted file mode 100644
index cdedf48b0c0..00000000000
--- a/app/services/merge_requests/auto_merge_service.rb
+++ /dev/null
@@ -1,30 +0,0 @@
-module MergeRequests
-  # AutoMergeService class
-  #
-  # Do git merge in satellite and in case of success
-  # mark merge request as merged and execute all hooks and notifications
-  # Called when you do merge via GitLab UI
-  class AutoMergeService < BaseMergeService
-    def execute(merge_request, commit_message)
-      merge_request.lock_mr
-
-      if Gitlab::Satellite::MergeAction.new(current_user, merge_request).merge!(commit_message)
-        merge_request.merge
-
-        create_merge_event(merge_request, current_user)
-        create_note(merge_request)
-        notification_service.merge_mr(merge_request, current_user)
-        execute_hooks(merge_request, 'merge')
-
-        true
-      else
-        merge_request.unlock_mr
-        false
-      end
-    rescue
-      merge_request.unlock_mr if merge_request.locked?
-      merge_request.mark_as_unmergeable
-      false
-    end
-  end
-end
diff --git a/app/services/merge_requests/base_merge_service.rb b/app/services/merge_requests/base_merge_service.rb
deleted file mode 100644
index 9579573adf9..00000000000
--- a/app/services/merge_requests/base_merge_service.rb
+++ /dev/null
@@ -1,10 +0,0 @@
-module MergeRequests
-  class BaseMergeService < MergeRequests::BaseService
-
-    private
-
-    def create_merge_event(merge_request, current_user)
-      EventCreateService.new.merge_mr(merge_request, current_user)
-    end
-  end
-end
diff --git a/app/services/merge_requests/build_service.rb b/app/services/merge_requests/build_service.rb
index 956480938c3..a9b29f9654d 100644
--- a/app/services/merge_requests/build_service.rb
+++ b/app/services/merge_requests/build_service.rb
@@ -12,12 +12,16 @@ module MergeRequests
       merge_request.target_project ||= (project.forked_from_project || project)
       merge_request.target_branch ||= merge_request.target_project.default_branch
 
-      unless merge_request.target_branch && merge_request.source_branch
-        return build_failed(merge_request, nil)
+      if merge_request.target_branch.blank? || merge_request.source_branch.blank?
+        message =
+          if params[:source_branch] || params[:target_branch]
+            "You must select source and target branch"
+          end
+
+        return build_failed(merge_request, message)
       end
 
       compare_result = CompareService.new.execute(
-        current_user,
         merge_request.source_project,
         merge_request.source_branch,
         merge_request.target_project,
@@ -40,7 +44,6 @@ module MergeRequests
           merge_request.compare_diffs = diffs
 
         elsif diffs == false
-          # satellite timeout return false
           merge_request.can_be_created = false
           merge_request.compare_failed = true
         end
@@ -59,9 +62,6 @@ module MergeRequests
       end
 
       merge_request
-
-    rescue Gitlab::Satellite::BranchesWithoutParent
-      return build_failed(merge_request, "Selected branches have no common commit so they cannot be merged.")
     end
 
     def build_failed(merge_request, message)
diff --git a/app/services/merge_requests/merge_service.rb b/app/services/merge_requests/merge_service.rb
index 327ead4ff3f..2107529a21a 100644
--- a/app/services/merge_requests/merge_service.rb
+++ b/app/services/merge_requests/merge_service.rb
@@ -1,22 +1,57 @@
 module MergeRequests
   # MergeService class
   #
-  # Mark existing merge request as merged
-  # and execute all hooks and notifications
-  # Called when you do merge via command line and push code
-  # to target branch
-  class MergeService < BaseMergeService
+  # Do git merge and in case of success
+  # mark merge request as merged and execute all hooks and notifications
+  # Executed when you do merge via GitLab UI
+  #
+  class MergeService < MergeRequests::BaseService
+    attr_reader :merge_request, :commit_message
+
     def execute(merge_request, commit_message)
-      merge_request.merge
+      @commit_message = commit_message
+      @merge_request = merge_request
 
-      create_merge_event(merge_request, current_user)
-      create_note(merge_request)
-      notification_service.merge_mr(merge_request, current_user)
-      execute_hooks(merge_request, 'merge')
+      unless @merge_request.mergeable?
+        return error('Merge request is not mergeable')
+      end
+
+      merge_request.in_locked_state do
+        if merge_changes
+          after_merge
+          success
+        else
+          error('Can not merge changes')
+        end
+      end
+    end
+
+    private
+
+    def merge_changes
+      if sha = commit
+        after_commit(sha, merge_request.target_branch)
+      end
+    end
+
+    def commit
+      committer = repository.user_to_comitter(current_user)
+
+      options = {
+        message: commit_message,
+        author: committer,
+        committer: committer
+      }
+
+      repository.merge(merge_request.source_sha, merge_request.target_branch, options)
+    end
+
+    def after_commit(sha, branch)
+      PostCommitService.new(project, current_user).execute(sha, branch)
+    end
 
-      true
-    rescue
-      false
+    def after_merge
+      MergeRequests::PostMergeService.new(project, current_user).execute(merge_request)
     end
   end
 end
diff --git a/app/services/merge_requests/post_merge_service.rb b/app/services/merge_requests/post_merge_service.rb
new file mode 100644
index 00000000000..aceb8cb9021
--- /dev/null
+++ b/app/services/merge_requests/post_merge_service.rb
@@ -0,0 +1,22 @@
+module MergeRequests
+  # PostMergeService class
+  #
+  # Mark existing merge request as merged
+  # and execute all hooks and notifications
+  #
+  class PostMergeService < MergeRequests::BaseService
+    def execute(merge_request)
+      merge_request.mark_as_merged
+      create_merge_event(merge_request, current_user)
+      create_note(merge_request)
+      notification_service.merge_mr(merge_request, current_user)
+      execute_hooks(merge_request, 'merge')
+    end
+
+    private
+
+    def create_merge_event(merge_request, current_user)
+      EventCreateService.new.merge_mr(merge_request, current_user)
+    end
+  end
+end
diff --git a/app/services/merge_requests/refresh_service.rb b/app/services/merge_requests/refresh_service.rb
index d0648da049b..e903e48e3cd 100644
--- a/app/services/merge_requests/refresh_service.rb
+++ b/app/services/merge_requests/refresh_service.rb
@@ -33,9 +33,9 @@ module MergeRequests
 
 
       merge_requests.uniq.select(&:source_project).each do |merge_request|
-        MergeRequests::MergeService.
+        MergeRequests::PostMergeService.
           new(merge_request.target_project, @current_user).
-          execute(merge_request, nil)
+          execute(merge_request)
       end
     end
 
diff --git a/app/services/post_commit_service.rb b/app/services/post_commit_service.rb
new file mode 100644
index 00000000000..8592c8d238b
--- /dev/null
+++ b/app/services/post_commit_service.rb
@@ -0,0 +1,71 @@
+class PostCommitService < BaseService
+  include Gitlab::Popen
+
+  attr_reader :changes, :repo_path
+
+  def execute(sha, branch)
+    commit = repository.commit(sha)
+    full_ref = Gitlab::Git::BRANCH_REF_PREFIX + branch
+    old_sha = commit.parent_id || Gitlab::Git::BLANK_SHA
+    @changes = "#{old_sha} #{sha} #{full_ref}"
+    @repo_path = repository.path_to_repo
+
+    post_receive
+  end
+
+  private
+
+  def post_receive
+    hook = hook_file('post-receive', repo_path)
+    return true if hook.nil?
+    call_receive_hook(hook)
+  end
+
+  def call_receive_hook(hook)
+    # function  will return true if succesful
+    exit_status = false
+
+    vars = {
+      'GL_ID' => Gitlab::ShellEnv.gl_id(current_user),
+      'PWD' => repo_path
+    }
+
+    options = {
+      chdir: repo_path
+    }
+
+    # we combine both stdout and stderr as we don't know what stream
+    # will be used by the custom hook
+    Open3.popen2e(vars, hook, options) do |stdin, stdout_stderr, wait_thr|
+      exit_status = true
+      stdin.sync = true
+
+      # in git, pre- and post- receive hooks may just exit without
+      # reading stdin. We catch the exception to avoid a broken pipe
+      # warning
+      begin
+        # inject all the changes as stdin to the hook
+        changes.lines do |line|
+          stdin.puts line
+        end
+      rescue Errno::EPIPE
+      end
+
+      # need to close stdin before reading stdout
+      stdin.close
+
+      # only output stdut_stderr if scripts doesn't return 0
+      unless wait_thr.value == 0
+        exit_status = false
+      end
+    end
+
+    exit_status
+  end
+
+  def hook_file(hook_type, repo_path)
+    hook_path = File.join(repo_path.strip, 'hooks')
+    hook_file = "#{hook_path}/#{hook_type}"
+    hook_file if File.exist?(hook_file)
+  end
+end
diff --git a/app/services/projects/destroy_service.rb b/app/services/projects/destroy_service.rb
index 403f419ec50..28872c89259 100644
--- a/app/services/projects/destroy_service.rb
+++ b/app/services/projects/destroy_service.rb
@@ -27,7 +27,6 @@ module Projects
         end
       end
 
-      project.satellite.destroy
       log_info("Project \"#{project.name}\" was removed")
       system_hook_service.execute_hooks_for(project, :destroy)
       true
diff --git a/app/services/projects/transfer_service.rb b/app/services/projects/transfer_service.rb
index f43c0ef70e9..550ed6897dd 100644
--- a/app/services/projects/transfer_service.rb
+++ b/app/services/projects/transfer_service.rb
@@ -33,9 +33,6 @@ module Projects
           raise TransferError.new("Project with same path in target namespace already exists")
         end
 
-        # Remove old satellite
-        project.satellite.destroy
-
         # Apply new namespace id
         project.namespace = new_namespace
         project.save!
@@ -51,9 +48,6 @@ module Projects
         # Move wiki repo also if present
         gitlab_shell.mv_repository("#{old_path}.wiki", "#{new_path}.wiki")
 
-        # Create a new satellite (reload project from DB)
-        Project.find(project.id).ensure_satellite_exists
-
         # clear project cached events
         project.reset_events_cache