Add API endpoint for accessing repo topics (#7963)

* Create API endpoints for repo topics.

Signed-off-by: David Svantesson <davidsvantesson@gmail.com>

* Generate swagger

Signed-off-by: David Svantesson <davidsvantesson@gmail.com>

* Add documentation to functions

Signed-off-by: David Svantesson <davidsvantesson@gmail.com>

* Grammar fix

Signed-off-by: David Svantesson <davidsvantesson@gmail.com>

* Fix function comment

Signed-off-by: David Svantesson <davidsvantesson@gmail.com>

* Can't use FindTopics when looking for a single repo topic, as it doesnt use exact match

Signed-off-by: David Svantesson <davidsvantesson@gmail.com>

* Add PUT ​/repos​/{owner}​/{repo}​/topics and remove GET ​/repos​/{owner}​/{repo}​/topics

* Ignore if topic is sent twice in same request, refactoring.

Signed-off-by: David Svantesson <davidsvantesson@gmail.com>

* Fix topic dropdown with api changes.

Signed-off-by: David Svantesson <davidsvantesson@gmail.com>

* Style fix

Signed-off-by: David Svantesson <davidsvantesson@gmail.com>

* Update API documentation

Signed-off-by: David Svantesson <davidsvantesson@gmail.com>

* Better way to handle duplicate topics in slice

Signed-off-by: David Svantesson <davidsvantesson@gmail.com>

* Make response element TopicName an array of strings, instead of using an array of TopicName

Signed-off-by: David Svantesson <davidsvantesson@gmail.com>

* Add test cases for API Repo Topics.

Signed-off-by: David Svantesson <davidsvantesson@gmail.com>

* Fix format of tests

Signed-off-by: David Svantesson <davidsvantesson@gmail.com>

* Fix comments

Signed-off-by: David Svantesson <davidsvantesson@gmail.com>

* Fix unit tests after adding some more topics to the test fixture.

Signed-off-by: David Svantesson <davidsvantesson@gmail.com>

* Update models/topic.go

Limit multiple if else if ...

Co-Authored-By: Antoine GIRARD <sapk@users.noreply.github.com>

* Engine as first parameter in function

Co-Authored-By: Antoine GIRARD <sapk@users.noreply.github.com>

* Replace magic numbers with http status code constants.

Signed-off-by: David Svantesson <davidsvantesson@gmail.com>

* Fix variable scope

Signed-off-by: David Svantesson <davidsvantesson@gmail.com>

* Test one read with login and one with token

Signed-off-by: David Svantesson <davidsvantesson@gmail.com>

* Add some more tests

Signed-off-by: David Svantesson <davidsvantesson@gmail.com>

* Apply suggestions from code review

Use empty struct for efficiency

Co-Authored-By: Lauris BH <lauris@nix.lv>

* Add test case to check access for user with write access

Signed-off-by: David Svantesson <davidsvantesson@gmail.com>

* Fix access, repo admin required to change topics

Signed-off-by: David Svantesson <davidsvantesson@gmail.com>

* Correct first test to be without token

Signed-off-by: David Svantesson <davidsvantesson@gmail.com>

* Any repo reader should be able to access topics.

* No need for string pointer

Signed-off-by: David Svantesson <davidsvantesson@gmail.com>

4 files changed, 153 insertions, 36 deletions

diff --git a/models/fixtures/repo_topic.yml b/models/fixtures/repo_topic.yml
index 7041ccfd09..f166faccc1 100644
--- a/models/fixtures/repo_topic.yml
+++ b/models/fixtures/repo_topic.yml
@@ -17,3 +17,11 @@
 -
   repo_id: 33
   topic_id: 4
+
+-
+  repo_id: 2
+  topic_id: 5
+
+-
+  repo_id: 2
+  topic_id: 6
diff --git a/models/fixtures/topic.yml b/models/fixtures/topic.yml
index c868b207cb..6cd0b37fa1 100644
--- a/models/fixtures/topic.yml
+++ b/models/fixtures/topic.yml
@@ -15,3 +15,11 @@
 - id: 4
   name: graphql
   repo_count: 1
+
+- id: 5
+  name: topicname1
+  repo_count: 1
+
+- id: 6
+  name: topicname2
+  repo_count: 2
diff --git a/models/topic.go b/models/topic.go
index 8a587acc3a..e4fda03fc4 100644
--- a/models/topic.go
+++ b/models/topic.go
@@ -54,11 +54,38 @@ func (err ErrTopicNotExist) Error() string {
 	return fmt.Sprintf("topic is not exist [name: %s]", err.Name)
 }
 
-// ValidateTopic checks topics by length and match pattern rules
+// ValidateTopic checks a topic by length and match pattern rules
 func ValidateTopic(topic string) bool {
 	return len(topic) <= 35 && topicPattern.MatchString(topic)
 }
 
+// SanitizeAndValidateTopics sanitizes and checks an array or topics
+func SanitizeAndValidateTopics(topics []string) (validTopics []string, invalidTopics []string) {
+	validTopics = make([]string, 0)
+	mValidTopics := make(map[string]struct{})
+	invalidTopics = make([]string, 0)
+
+	for _, topic := range topics {
+		topic = strings.TrimSpace(strings.ToLower(topic))
+		// ignore empty string
+		if len(topic) == 0 {
+			continue
+		}
+		// ignore same topic twice
+		if _, ok := mValidTopics[topic]; ok {
+			continue
+		}
+		if ValidateTopic(topic) {
+			validTopics = append(validTopics, topic)
+			mValidTopics[topic] = struct{}{}
+		} else {
+			invalidTopics = append(invalidTopics, topic)
+		}
+	}
+
+	return validTopics, invalidTopics
+}
+
 // GetTopicByName retrieves topic by name
 func GetTopicByName(name string) (*Topic, error) {
 	var topic Topic
@@ -70,6 +97,54 @@ func GetTopicByName(name string) (*Topic, error) {
 	return &topic, nil
 }
 
+// addTopicByNameToRepo adds a topic name to a repo and increments the topic count.
+// Returns topic after the addition
+func addTopicByNameToRepo(e Engine, repoID int64, topicName string) (*Topic, error) {
+	var topic Topic
+	has, err := e.Where("name = ?", topicName).Get(&topic)
+	if err != nil {
+		return nil, err
+	}
+	if !has {
+		topic.Name = topicName
+		topic.RepoCount = 1
+		if _, err := e.Insert(&topic); err != nil {
+			return nil, err
+		}
+	} else {
+		topic.RepoCount++
+		if _, err := e.ID(topic.ID).Cols("repo_count").Update(&topic); err != nil {
+			return nil, err
+		}
+	}
+
+	if _, err := e.Insert(&RepoTopic{
+		RepoID:  repoID,
+		TopicID: topic.ID,
+	}); err != nil {
+		return nil, err
+	}
+
+	return &topic, nil
+}
+
+// removeTopicFromRepo remove a topic from a repo and decrements the topic repo count
+func removeTopicFromRepo(repoID int64, topic *Topic, e Engine) error {
+	topic.RepoCount--
+	if _, err := e.ID(topic.ID).Cols("repo_count").Update(topic); err != nil {
+		return err
+	}
+
+	if _, err := e.Delete(&RepoTopic{
+		RepoID:  repoID,
+		TopicID: topic.ID,
+	}); err != nil {
+		return err
+	}
+
+	return nil
+}
+
 // FindTopicOptions represents the options when fdin topics
 type FindTopicOptions struct {
 	RepoID  int64
@@ -103,6 +178,50 @@ func FindTopics(opts *FindTopicOptions) (topics []*Topic, err error) {
 	return topics, sess.Desc("topic.repo_count").Find(&topics)
 }
 
+// GetRepoTopicByName retrives topic from name for a repo if it exist
+func GetRepoTopicByName(repoID int64, topicName string) (*Topic, error) {
+	var cond = builder.NewCond()
+	var topic Topic
+	cond = cond.And(builder.Eq{"repo_topic.repo_id": repoID}).And(builder.Eq{"topic.name": topicName})
+	sess := x.Table("topic").Where(cond)
+	sess.Join("INNER", "repo_topic", "repo_topic.topic_id = topic.id")
+	has, err := sess.Get(&topic)
+	if has {
+		return &topic, err
+	}
+	return nil, err
+}
+
+// AddTopic adds a topic name to a repository (if it does not already have it)
+func AddTopic(repoID int64, topicName string) (*Topic, error) {
+	topic, err := GetRepoTopicByName(repoID, topicName)
+	if err != nil {
+		return nil, err
+	}
+	if topic != nil {
+		// Repo already have topic
+		return topic, nil
+	}
+
+	return addTopicByNameToRepo(x, repoID, topicName)
+}
+
+// DeleteTopic removes a topic name from a repository (if it has it)
+func DeleteTopic(repoID int64, topicName string) (*Topic, error) {
+	topic, err := GetRepoTopicByName(repoID, topicName)
+	if err != nil {
+		return nil, err
+	}
+	if topic == nil {
+		// Repo doesn't have topic, can't be removed
+		return nil, nil
+	}
+
+	err = removeTopicFromRepo(repoID, topic, x)
+
+	return topic, err
+}
+
 // SaveTopics save topics to a repository
 func SaveTopics(repoID int64, topicNames ...string) error {
 	topics, err := FindTopics(&FindTopicOptions{
@@ -152,40 +271,15 @@ func SaveTopics(repoID int64, topicNames ...string) error {
 	}
 
 	for _, topicName := range addedTopicNames {
-		var topic Topic
-		if has, err := sess.Where("name = ?", topicName).Get(&topic); err != nil {
-			return err
-		} else if !has {
-			topic.Name = topicName
-			topic.RepoCount = 1
-			if _, err := sess.Insert(&topic); err != nil {
-				return err
-			}
-		} else {
-			topic.RepoCount++
-			if _, err := sess.ID(topic.ID).Cols("repo_count").Update(&topic); err != nil {
-				return err
-			}
-		}
-
-		if _, err := sess.Insert(&RepoTopic{
-			RepoID:  repoID,
-			TopicID: topic.ID,
-		}); err != nil {
+		_, err := addTopicByNameToRepo(sess, repoID, topicName)
+		if err != nil {
 			return err
 		}
 	}
 
 	for _, topic := range removeTopics {
-		topic.RepoCount--
-		if _, err := sess.ID(topic.ID).Cols("repo_count").Update(topic); err != nil {
-			return err
-		}
-
-		if _, err := sess.Delete(&RepoTopic{
-			RepoID:  repoID,
-			TopicID: topic.ID,
-		}); err != nil {
+		err := removeTopicFromRepo(repoID, topic, sess)
+		if err != nil {
 			return err
 		}
 	}
diff --git a/models/topic_test.go b/models/topic_test.go
index 65e52afb12..c173c7bf2a 100644
--- a/models/topic_test.go
+++ b/models/topic_test.go
@@ -11,11 +11,15 @@ import (
 )
 
 func TestAddTopic(t *testing.T) {
+	totalNrOfTopics := 6
+	repo1NrOfTopics := 3
+	repo2NrOfTopics := 2
+
 	assert.NoError(t, PrepareTestDatabase())
 
 	topics, err := FindTopics(&FindTopicOptions{})
 	assert.NoError(t, err)
-	assert.EqualValues(t, 4, len(topics))
+	assert.EqualValues(t, totalNrOfTopics, len(topics))
 
 	topics, err = FindTopics(&FindTopicOptions{
 		Limit: 2,
@@ -27,33 +31,36 @@ func TestAddTopic(t *testing.T) {
 		RepoID: 1,
 	})
 	assert.NoError(t, err)
-	assert.EqualValues(t, 3, len(topics))
+	assert.EqualValues(t, repo1NrOfTopics, len(topics))
 
 	assert.NoError(t, SaveTopics(2, "golang"))
+	repo2NrOfTopics = 1
 	topics, err = FindTopics(&FindTopicOptions{})
 	assert.NoError(t, err)
-	assert.EqualValues(t, 4, len(topics))
+	assert.EqualValues(t, totalNrOfTopics, len(topics))
 
 	topics, err = FindTopics(&FindTopicOptions{
 		RepoID: 2,
 	})
 	assert.NoError(t, err)
-	assert.EqualValues(t, 1, len(topics))
+	assert.EqualValues(t, repo2NrOfTopics, len(topics))
 
 	assert.NoError(t, SaveTopics(2, "golang", "gitea"))
+	repo2NrOfTopics = 2
+	totalNrOfTopics++
 	topic, err := GetTopicByName("gitea")
 	assert.NoError(t, err)
 	assert.EqualValues(t, 1, topic.RepoCount)
 
 	topics, err = FindTopics(&FindTopicOptions{})
 	assert.NoError(t, err)
-	assert.EqualValues(t, 5, len(topics))
+	assert.EqualValues(t, totalNrOfTopics, len(topics))
 
 	topics, err = FindTopics(&FindTopicOptions{
 		RepoID: 2,
 	})
 	assert.NoError(t, err)
-	assert.EqualValues(t, 2, len(topics))
+	assert.EqualValues(t, repo2NrOfTopics, len(topics))
 }
 
 func TestTopicValidator(t *testing.T) {