feat: Implement issue link type POST

issuelinktype.go

@@ -1,6 +1,10 @@
 package jira
 
-import "fmt"
+import (
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+)
 
 // IssueLinkTypeService handles issue link types for the JIRA instance / API.
 //
@@ -44,3 +48,33 @@ func (s *IssueLinkTypeService) Get(ID string) (*IssueLinkType, *Response, error)
 	}
 	return linkType, resp, nil
 }
+
+// Create creates an issue link type in JIRA.
+//
+// JIRA API docs: https://developer.atlassian.com/cloud/jira/platform/rest/v2/#api-rest-api-2-issueLinkType-post
+func (s *IssueLinkTypeService) Create(linkType *IssueLinkType) (*IssueLinkType, *Response, error) {
+	apiEndpoint := "/rest/api/2/issueLinkType"
+	req, err := s.client.NewRequest("POST", apiEndpoint, linkType)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	resp, err := s.client.Do(req, nil)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	responseLinkType := new(IssueLinkType)
+	defer resp.Body.Close()
+	data, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		e := fmt.Errorf("Could not read the returned data")
+		return nil, resp, NewJiraError(resp, e)
+	}
+	err = json.Unmarshal(data, responseLinkType)
+	if err != nil {
+		e := fmt.Errorf("Could no unmarshal the data into struct")
+		return nil, resp, NewJiraError(resp, e)
+	}
+	return linkType, resp, nil
+}

issuelinktype_test.go

@@ -48,3 +48,28 @@ func TestIssueLinkTypeService_Get(t *testing.T) {
 		t.Error("Expected linkType. LinkType is nil")
 	}
 }
+
+func TestIssueLinkTypeService_Create(t *testing.T) {
+	setup()
+	defer teardown()
+	testMux.HandleFunc("/rest/api/2/issueLinkType", func(w http.ResponseWriter, r *http.Request) {
+		testMethod(t, r, "POST")
+		testRequestURL(t, r, "/rest/api/2/issueLinkType")
+
+		w.WriteHeader(http.StatusCreated)
+		fmt.Fprint(w, `{"id":"10021","name":"Problem/Incident","inward":"is caused by",
+		"outward":"causes","self":"https://www.example.com/jira/rest/api/2/issueLinkType/10021"}`)
+	})
+
+	lt := &IssueLinkType{
+		Name:    "Problem/Incident",
+		Inward:  "is caused by",
+		Outward: "causes",
+	}
+
+	if linkType, _, err := testClient.IssueLinkType.Create(lt); err != nil {
+		t.Errorf("Error given: %s", err)
+	} else if linkType == nil {
+		t.Error("Expected linkType. LinkType is nil")
+	}
+}