refactor: create tasks in coderd instead of frontend (#19280)

Instead of creating tasks with a specialized call to `CreateWorkspace`
on the frontend, we instead lift this to the backend and allow the
frontend to simply call `CreateAITask`.

coderd/aitasks.go

@@ -1,13 +1,20 @@
 package coderd
 
 import (
+	"database/sql"
+	"errors"
 	"fmt"
 	"net/http"
+	"slices"
 	"strings"
 
 	"github.com/google/uuid"
 
+	"github.com/coder/coder/v2/coderd/audit"
+	"github.com/coder/coder/v2/coderd/database"
 	"github.com/coder/coder/v2/coderd/httpapi"
+	"github.com/coder/coder/v2/coderd/httpmw"
+	"github.com/coder/coder/v2/coderd/rbac"
 	"github.com/coder/coder/v2/codersdk"
 )
 
@@ -61,3 +68,106 @@ func (api *API) aiTasksPrompts(rw http.ResponseWriter, r *http.Request) {
 		Prompts: promptsByBuildID,
 	})
 }
+
+// This endpoint is experimental and not guaranteed to be stable, so we're not
+// generating public-facing documentation for it.
+func (api *API) tasksCreate(rw http.ResponseWriter, r *http.Request) {
+	var (
+		ctx     = r.Context()
+		apiKey  = httpmw.APIKey(r)
+		auditor = api.Auditor.Load()
+		mems    = httpmw.OrganizationMembersParam(r)
+	)
+
+	var req codersdk.CreateTaskRequest
+	if !httpapi.Read(ctx, rw, r, &req) {
+		return
+	}
+
+	hasAITask, err := api.Database.GetTemplateVersionHasAITask(ctx, req.TemplateVersionID)
+	if err != nil {
+		if errors.Is(err, sql.ErrNoRows) || rbac.IsUnauthorizedError(err) {
+			httpapi.ResourceNotFound(rw)
+			return
+		}
+
+		httpapi.Write(ctx, rw, http.StatusInternalServerError, codersdk.Response{
+			Message: "Internal error fetching whether the template version has an AI task.",
+			Detail:  err.Error(),
+		})
+		return
+	}
+	if !hasAITask {
+		httpapi.Write(ctx, rw, http.StatusBadRequest, codersdk.Response{
+			Message: fmt.Sprintf(`Template does not have required parameter %q`, codersdk.AITaskPromptParameterName),
+		})
+		return
+	}
+
+	createReq := codersdk.CreateWorkspaceRequest{
+		Name:                    req.Name,
+		TemplateVersionID:       req.TemplateVersionID,
+		TemplateVersionPresetID: req.TemplateVersionPresetID,
+		RichParameterValues: []codersdk.WorkspaceBuildParameter{
+			{Name: codersdk.AITaskPromptParameterName, Value: req.Prompt},
+		},
+	}
+
+	var owner workspaceOwner
+	if mems.User != nil {
+		// This user fetch is an optimization path for the most common case of creating a
+		// task for 'Me'.
+		//
+		// This is also required to allow `owners` to create workspaces for users
+		// that are not in an organization.
+		owner = workspaceOwner{
+			ID:        mems.User.ID,
+			Username:  mems.User.Username,
+			AvatarURL: mems.User.AvatarURL,
+		}
+	} else {
+		// A task can still be created if the caller can read the organization
+		// member. The organization is required, which can be sourced from the
+		// template.
+		//
+		// TODO: This code gets called twice for each workspace build request.
+		//   This is inefficient and costs at most 2 extra RTTs to the DB.
+		//   This can be optimized. It exists as it is now for code simplicity.
+		//   The most common case is to create a workspace for 'Me'. Which does
+		//   not enter this code branch.
+		template, ok := requestTemplate(ctx, rw, createReq, api.Database)
+		if !ok {
+			return
+		}
+
+		// If the caller can find the organization membership in the same org
+		// as the template, then they can continue.
+		orgIndex := slices.IndexFunc(mems.Memberships, func(mem httpmw.OrganizationMember) bool {
+			return mem.OrganizationID == template.OrganizationID
+		})
+		if orgIndex == -1 {
+			httpapi.ResourceNotFound(rw)
+			return
+		}
+
+		member := mems.Memberships[orgIndex]
+		owner = workspaceOwner{
+			ID:        member.UserID,
+			Username:  member.Username,
+			AvatarURL: member.AvatarURL,
+		}
+	}
+
+	aReq, commitAudit := audit.InitRequest[database.WorkspaceTable](rw, &audit.RequestParams{
+		Audit:   *auditor,
+		Log:     api.Logger,
+		Request: r,
+		Action:  database.AuditActionCreate,
+		AdditionalFields: audit.AdditionalFields{
+			WorkspaceOwner: owner.Username,
+		},
+	})
+
+	defer commitAudit()
+	createWorkspace(ctx, aReq, apiKey.UserID, api, owner, createReq, rw, r)
+}