[bug] Reuse and close connections per resource

This commit changes the way we handle connections
and clients:

- It now creates the connection to the controlplane
  at provider level and passed down to the
  resources.
- It does the same with the authentication token.
- Now, after every method is run, we close the
  connection created with the dataplane. Previously
  we were leaving the connection open causing a
  lot of port usage on every terraform command
  that the user ran.

redpanda/clients/clients.go → redpanda/cloud/cloud.go

@@ -13,9 +13,9 @@
 //    See the License for the specific language governing permissions and
 //    limitations under the License.
 
-// Package clients provides the CloudV2 clients used by the Redpanda terraform
-// provider and the generated resources.
-package clients
+// Package cloud provides the methods to connect and talk to the Redpanda Cloud
+// public API.
+package cloud
 
 import (
 	"context"
@@ -36,15 +36,15 @@ import (
 	"google.golang.org/grpc/metadata"
 )
 
-// cloudEndpoint is a representation of a cloud V2 endpoint, containing the URLs
-// for authentication and the API URL.
-type cloudEndpoint struct {
-	apiURL   string // CloudV2 public API URL.
+// Endpoint is a representation of a cloud endpoint for a single environment. It
+// contains the URLs, audience for authentication and the API URL.
+type Endpoint struct {
+	APIURL   string // CloudV2 public API URL.
 	authURL  string // CloudV2 URL for authorization token exchange.
 	audience string // CloudV2 audience used for token exchange.
 }
 
-var cloudAuthEnvironments = map[string]cloudEndpoint{
+var endpoints = map[string]Endpoint{
 	"dev": {
 		"api.dev.cloud.redpanda.com:443",
 		"https://dev-cloudv2.us.auth0.com/oauth/token",
@@ -62,33 +62,27 @@ var cloudAuthEnvironments = map[string]cloudEndpoint{
 	},
 }
 
-// ClientRequest are the client request credentials used to create a connection.
-type ClientRequest struct {
-	ClientID     string
-	ClientSecret string
-	// TODO: we can use this as the only source of truth for Client Credentials and Envs.
-}
-
 type tokenResponse struct {
 	AccessToken string `json:"access_token"`
 	Scope       string `json:"scope"`
 	ExpiresIn   int    `json:"expires_in"`
 	TokenType   string `json:"token_type"`
 }
 
-// requestTokenAndEnv requests a token.
-func requestTokenAndEnv(ctx context.Context, cloudEnv string, cr ClientRequest) (string, *cloudEndpoint, error) {
-	if cr.ClientID == "" {
+// RequestTokenAndEnv requests an authentication token and return the Endpoint
+// for a given environment.
+func RequestTokenAndEnv(ctx context.Context, cloudEnv, clientID, clientSecret string) (string, *Endpoint, error) {
+	if clientID == "" {
 		return "", nil, fmt.Errorf("client_id is not set")
 	}
-	if cr.ClientSecret == "" {
+	if clientSecret == "" {
 		return "", nil, fmt.Errorf("client_secret is not set")
 	}
-	endpoint, found := cloudAuthEnvironments[cloudEnv]
+	endpoint, found := endpoints[cloudEnv]
 	if !found {
 		return "", nil, fmt.Errorf("unable to find requested environment: %q", cloudEnv)
 	}
-	payload := fmt.Sprintf("grant_type=client_credentials&client_id=%s&client_secret=%s&audience=%s", cr.ClientID, cr.ClientSecret, endpoint.audience)
+	payload := fmt.Sprintf("grant_type=client_credentials&client_id=%s&client_secret=%s&audience=%s", clientID, clientSecret, endpoint.audience)
 	req, err := http.NewRequestWithContext(ctx, "POST", endpoint.authURL, strings.NewReader(payload))
 	if err != nil {
 		return "", nil, fmt.Errorf("unable to issue request to %v: %v", endpoint.authURL, err)
@@ -118,7 +112,9 @@ func requestTokenAndEnv(ctx context.Context, cloudEnv string, cr ClientRequest)
 	return tokenContainer.AccessToken, &endpoint, nil
 }
 
-func spawnConn(ctx context.Context, url string, authToken string) (*grpc.ClientConn, error) {
+// SpawnConn returns a grpc connection to the given URL, it adds a bearer token
+// to each request with the given 'authToken'.
+func SpawnConn(ctx context.Context, url string, authToken string) (*grpc.ClientConn, error) {
 	return grpc.DialContext(
 		ctx,
 		url,

redpanda/config/config.go

@@ -0,0 +1,42 @@
+// Copyright 2024 Redpanda Data, Inc.
+//
+//
+//    Licensed under the Apache License, Version 2.0 (the "License");
+//    you may not use this file except in compliance with the License.
+//    You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+//    Unless required by applicable law or agreed to in writing, software
+//    distributed under the License is distributed on an "AS IS" BASIS,
+//    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+//    See the License for the specific language governing permissions and
+//    limitations under the License.
+
+// Package config contains the configuration structs to initialize our clients
+// and provider.
+package config
+
+import "google.golang.org/grpc"
+
+// Resource is the config used to pass data and dependencies to resource
+// implementations.
+type Resource struct {
+	AuthToken              string
+	ClientID               string
+	ClientSecret           string
+	CloudEnv               string
+	ControlPlaneConnection *grpc.ClientConn
+}
+
+// Datasource is the config used to pass data and dependencies to data source
+// implementations.
+type Datasource struct {
+	AuthToken              string
+	ClientID               string
+	ClientSecret           string
+	CloudEnv               string
+	ControlPlaneConnection *grpc.ClientConn
+}
+
+// TODO add cloud provider and region as values to persist

redpanda/redpanda.go

@@ -26,14 +26,16 @@ import (
 	"github.com/hashicorp/terraform-plugin-framework/provider"
 	"github.com/hashicorp/terraform-plugin-framework/provider/schema"
 	"github.com/hashicorp/terraform-plugin-framework/resource"
+	"github.com/redpanda-data/terraform-provider-redpanda/redpanda/cloud"
+	"github.com/redpanda-data/terraform-provider-redpanda/redpanda/config"
 	"github.com/redpanda-data/terraform-provider-redpanda/redpanda/models"
 	"github.com/redpanda-data/terraform-provider-redpanda/redpanda/resources/acl"
 	"github.com/redpanda-data/terraform-provider-redpanda/redpanda/resources/cluster"
 	"github.com/redpanda-data/terraform-provider-redpanda/redpanda/resources/namespace"
 	"github.com/redpanda-data/terraform-provider-redpanda/redpanda/resources/network"
 	"github.com/redpanda-data/terraform-provider-redpanda/redpanda/resources/topic"
 	"github.com/redpanda-data/terraform-provider-redpanda/redpanda/resources/user"
-	"github.com/redpanda-data/terraform-provider-redpanda/redpanda/utils"
+	"google.golang.org/grpc"
 )
 
 // Ensure provider defined types fully satisfy framework interfaces.
@@ -46,6 +48,8 @@ type Redpanda struct {
 	cloudEnv string
 	// version is the Redpanda terraform provider.
 	version string
+	// conn is the connection to the control plane API.
+	conn *grpc.ClientConn
 }
 
 const (
@@ -118,15 +122,33 @@ func (r *Redpanda) Configure(ctx context.Context, request provider.ConfigureRequ
 	}
 	// Clients are passed through to downstream resources through the response
 	// struct.
-	response.ResourceData = utils.ResourceData{
-		ClientID:     id,
-		ClientSecret: sec,
-		CloudEnv:     r.cloudEnv,
+	token, endpoint, err := cloud.RequestTokenAndEnv(ctx, r.cloudEnv, id, sec)
+	if err != nil {
+		response.Diagnostics.AddError("failed to authenticate with Redpanda API", err.Error())
+		return
+	}
+	if r.conn == nil {
+		conn, err := cloud.SpawnConn(ctx, endpoint.APIURL, token)
+		if err != nil {
+			response.Diagnostics.AddError("failed to open a connection with the Redpanda Cloud API", err.Error())
+			return
+		}
+		r.conn = conn
+	}
+
+	response.ResourceData = config.Resource{
+		AuthToken:              token,
+		ClientID:               id,
+		ClientSecret:           sec,
+		CloudEnv:               r.cloudEnv,
+		ControlPlaneConnection: r.conn,
 	}
-	response.DataSourceData = utils.DatasourceData{
-		ClientID:     id,
-		ClientSecret: sec,
-		CloudEnv:     r.cloudEnv,
+	response.DataSourceData = config.Datasource{
+		AuthToken:              token,
+		ClientID:               id,
+		ClientSecret:           sec,
+		CloudEnv:               r.cloudEnv,
+		ControlPlaneConnection: r.conn,
 	}
 }