Fix MR Selection, Go Code Refactor (#358)

refactor: Refactors the Go codebase into a more modular and idiomatic approach
fix: require selection of specific MR when there are multiple targets for a given source branch
feat: Allows for the passing of Gitlab's filter options when choosing an MR, improves MR selection
feat: API to choose an MR from a list based on the provided username's involvement as an assignee/reviewer/author

This is a #MINOR release

cmd/app/pipeline.go

@@ -0,0 +1,173 @@
+package app
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"net/http"
+	"strconv"
+	"strings"
+
+	"github.com/harrisoncramer/gitlab.nvim/cmd/app/git"
+	"github.com/xanzy/go-gitlab"
+)
+
+type RetriggerPipelineResponse struct {
+	SuccessResponse
+	LatestPipeline *gitlab.Pipeline `json:"latest_pipeline"`
+}
+
+type PipelineWithJobs struct {
+	Jobs           []*gitlab.Job        `json:"jobs"`
+	LatestPipeline *gitlab.PipelineInfo `json:"latest_pipeline"`
+}
+
+type GetPipelineAndJobsResponse struct {
+	SuccessResponse
+	Pipeline PipelineWithJobs `json:"latest_pipeline"`
+}
+
+type PipelineManager interface {
+	ListProjectPipelines(pid interface{}, opt *gitlab.ListProjectPipelinesOptions, options ...gitlab.RequestOptionFunc) ([]*gitlab.PipelineInfo, *gitlab.Response, error)
+	ListPipelineJobs(pid interface{}, pipelineID int, opts *gitlab.ListJobsOptions, options ...gitlab.RequestOptionFunc) ([]*gitlab.Job, *gitlab.Response, error)
+	RetryPipelineBuild(pid interface{}, pipeline int, options ...gitlab.RequestOptionFunc) (*gitlab.Pipeline, *gitlab.Response, error)
+}
+
+type pipelineService struct {
+	data
+	client     PipelineManager
+	gitService git.GitManager
+}
+
+/*
+pipelineHandler fetches information about the current pipeline, and retriggers a pipeline run. For more detailed information
+about a given job in a pipeline, see the jobHandler function
+*/
+func (a pipelineService) handler(w http.ResponseWriter, r *http.Request) {
+	switch r.Method {
+	case http.MethodGet:
+		a.GetPipelineAndJobs(w, r)
+	case http.MethodPost:
+		a.RetriggerPipeline(w, r)
+	default:
+		w.Header().Set("Content-Type", "application/json")
+		w.Header().Set("Access-Control-Allow-Methods", fmt.Sprintf("%s, %s", http.MethodGet, http.MethodPost))
+		handleError(w, InvalidRequestError{}, "Expected GET or POST", http.StatusMethodNotAllowed)
+	}
+}
+
+/* Gets the latest pipeline for a given commit, returns an error if there is no pipeline */
+func (a pipelineService) GetLastPipeline(commit string) (*gitlab.PipelineInfo, error) {
+
+	l := &gitlab.ListProjectPipelinesOptions{
+		SHA:  gitlab.Ptr(commit),
+		Sort: gitlab.Ptr("desc"),
+	}
+
+	pipes, res, err := a.client.ListProjectPipelines(a.projectInfo.ProjectId, l)
+
+	if err != nil {
+		return nil, err
+	}
+
+	if res.StatusCode >= 300 {
+		return nil, errors.New("Could not get pipelines")
+	}
+
+	if len(pipes) == 0 {
+		return nil, errors.New("No pipeline running or available for commit " + commit)
+	}
+
+	return pipes[0], nil
+}
+
+/* Gets the latest pipeline and job information for the current branch */
+func (a pipelineService) GetPipelineAndJobs(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Content-Type", "application/json")
+
+	commit, err := a.gitService.GetLatestCommitOnRemote(pluginOptions.ConnectionSettings.Remote, a.gitInfo.BranchName)
+
+	if err != nil {
+		handleError(w, err, "Error getting commit on remote branch", http.StatusInternalServerError)
+		return
+	}
+
+	pipeline, err := a.GetLastPipeline(commit)
+
+	if err != nil {
+		handleError(w, err, fmt.Sprintf("Failed to get latest pipeline for %s branch", a.gitInfo.BranchName), http.StatusInternalServerError)
+		return
+	}
+
+	if pipeline == nil {
+		handleError(w, GenericError{endpoint: "/pipeline"}, fmt.Sprintf("No pipeline found for %s branch", a.gitInfo.BranchName), http.StatusInternalServerError)
+		return
+	}
+
+	jobs, res, err := a.client.ListPipelineJobs(a.projectInfo.ProjectId, pipeline.ID, &gitlab.ListJobsOptions{})
+
+	if err != nil {
+		handleError(w, err, "Could not get pipeline jobs", http.StatusInternalServerError)
+		return
+	}
+
+	if res.StatusCode >= 300 {
+		handleError(w, GenericError{endpoint: "/pipeline"}, "Could not get pipeline jobs", res.StatusCode)
+		return
+	}
+
+	w.WriteHeader(http.StatusOK)
+	response := GetPipelineAndJobsResponse{
+		SuccessResponse: SuccessResponse{
+			Status:  http.StatusOK,
+			Message: "Pipeline retrieved",
+		},
+		Pipeline: PipelineWithJobs{
+			LatestPipeline: pipeline,
+			Jobs:           jobs,
+		},
+	}
+
+	err = json.NewEncoder(w).Encode(response)
+	if err != nil {
+		handleError(w, err, "Could not encode response", http.StatusInternalServerError)
+	}
+}
+
+func (a pipelineService) RetriggerPipeline(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Content-Type", "application/json")
+
+	id := strings.TrimPrefix(r.URL.Path, "/pipeline/trigger/")
+
+	idInt, err := strconv.Atoi(id)
+	if err != nil {
+		handleError(w, err, "Could not convert pipeline ID to integer", http.StatusBadRequest)
+		return
+	}
+
+	pipeline, res, err := a.client.RetryPipelineBuild(a.projectInfo.ProjectId, idInt)
+
+	if err != nil {
+		handleError(w, err, "Could not retrigger pipeline", http.StatusInternalServerError)
+		return
+	}
+
+	if res.StatusCode >= 300 {
+		handleError(w, GenericError{endpoint: "/pipeline"}, "Could not retrigger pipeline", res.StatusCode)
+		return
+	}
+
+	w.WriteHeader(http.StatusOK)
+	response := RetriggerPipelineResponse{
+		SuccessResponse: SuccessResponse{
+			Message: "Pipeline retriggered",
+			Status:  http.StatusOK,
+		},
+		LatestPipeline: pipeline,
+	}
+
+	err = json.NewEncoder(w).Encode(response)
+	if err != nil {
+		handleError(w, err, "Could not encode response", http.StatusInternalServerError)
+	}
+}