Cache cloud-api response for 24h to improve responsiveness

Author: cmaglie

Diff for: commands/board/list.go

@@ -19,7 +19,7 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"net/http"
 	"regexp"
 	"sort"
@@ -32,6 +32,7 @@ import (
 	"github.com/arduino/arduino-cli/arduino/discovery"
 	"github.com/arduino/arduino-cli/arduino/httpclient"
 	"github.com/arduino/arduino-cli/commands"
+	"github.com/arduino/arduino-cli/inventory"
 	rpc "github.com/arduino/arduino-cli/rpc/cc/arduino/cli/commands/v1"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
@@ -59,52 +60,74 @@ func apiByVidPid(vid, pid string) ([]*rpc.BoardListItem, error) {
 		return nil, errors.Errorf(tr("Invalid pid value: '%s'"), pid)
 	}
 
-	url := fmt.Sprintf("%s/%s/%s", vidPidURL, vid, pid)
-	retVal := []*rpc.BoardListItem{}
-	req, _ := http.NewRequest("GET", url, nil)
-	req.Header.Set("Content-Type", "application/json")
+	var resp []byte
+	cacheKey := fmt.Sprintf("cache.builder-api.v3/boards/byvid/pid/%s/%s", vid, pid)
+	if cachedResp := inventory.Store.GetString(cacheKey + ".data"); cachedResp != "" {
+		ts := inventory.Store.GetInt64(cacheKey + ".ts")
+		if time.Now().Unix()-ts < 24*60*60 { // 24 hr timeout
+			if cachedResp == "ErrNotFound" {
+				return nil, ErrNotFound
+			}
+			resp = []byte(cachedResp)
+		}
+	}
 
-	// TODO: use proxy if set
+	if resp == nil {
+		url := fmt.Sprintf("%s/%s/%s", vidPidURL, vid, pid)
+		req, _ := http.NewRequest("GET", url, nil)
+		req.Header.Set("Content-Type", "application/json")
 
-	httpClient, err := httpclient.New()
+		// TODO: use proxy if set
 
-	if err != nil {
-		return nil, errors.Wrap(err, tr("failed to initialize http client"))
-	}
+		httpClient, err := httpclient.New()
 
-	if res, err := httpClient.Do(req); err == nil {
+		if err != nil {
+			return nil, errors.Wrap(err, tr("failed to initialize http client"))
+		}
+
+		res, err := httpClient.Do(req)
+		if err != nil {
+			return nil, errors.Wrap(err, tr("error querying Arduino Cloud Api"))
+		}
 		if res.StatusCode >= 400 {
 			if res.StatusCode == 404 {
+				inventory.Store.Set(cacheKey+".data", "ErrNotFound")
+				inventory.Store.Set(cacheKey+".ts", time.Now().Unix())
+				inventory.WriteStore()
 				return nil, ErrNotFound
 			}
 			return nil, errors.Errorf(tr("the server responded with status %s"), res.Status)
 		}
 
-		body, _ := ioutil.ReadAll(res.Body)
-		res.Body.Close()
-
-		var dat map[string]interface{}
-		err = json.Unmarshal(body, &dat)
+		resp, err = io.ReadAll(res.Body)
 		if err != nil {
-			return nil, errors.Wrap(err, tr("error processing response from server"))
+			return nil, err
+		}
+		if err := res.Body.Close(); err != nil {
+			return nil, err
 		}
 
-		name, nameFound := dat["name"].(string)
-		fqbn, fbqnFound := dat["fqbn"].(string)
+		inventory.Store.Set(cacheKey+".data", string(resp))
+		inventory.Store.Set(cacheKey+".ts", time.Now().Unix())
+		inventory.WriteStore()
+	}
 
-		if !nameFound || !fbqnFound {
-			return nil, errors.New(tr("wrong format in server response"))
-		}
+	var dat map[string]interface{}
+	if err := json.Unmarshal(resp, &dat); err != nil {
+		return nil, errors.Wrap(err, tr("error processing response from server"))
+	}
+	name, nameFound := dat["name"].(string)
+	fqbn, fbqnFound := dat["fqbn"].(string)
+	if !nameFound || !fbqnFound {
+		return nil, errors.New(tr("wrong format in server response"))
+	}
 
-		retVal = append(retVal, &rpc.BoardListItem{
+	return []*rpc.BoardListItem{
+		{
 			Name: name,
 			Fqbn: fqbn,
-		})
-	} else {
-		return nil, errors.Wrap(err, tr("error querying Arduino Cloud Api"))
-	}
-
-	return retVal, nil
+		},
+	}, nil
 }
 
 func identifyViaCloudAPI(port *discovery.Port) ([]*rpc.BoardListItem, error) {

Diff for: inventory/inventory.go

@@ -19,6 +19,7 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
+	"sync"
 
 	"github.com/arduino/arduino-cli/i18n"
 	"github.com/gofrs/uuid"
@@ -77,9 +78,14 @@ func generateInstallationData() error {
 	return nil
 }
 
+var writeStoreMux sync.Mutex
+
 // WriteStore writes the current information from Store to configFilePath.
 // Returns err if it fails.
 func WriteStore() error {
+	writeStoreMux.Lock()
+	defer writeStoreMux.Unlock()
+
 	configPath := filepath.Dir(configFilePath)
 
 	// Create config dir if not present,