Use Arduino CLI infrastructure for querying library index

In the past, I have found that using Arduino CLI infrastructure for handling projects is not always the right choice
because Arduino CLI is intended to be resilient to sub-ideal project configurations when feasible, whereas Arduino Lint
is intended to enforce or encourage ideal project configurations.

However, Arduino Lint is not intended to lint the Library Manager index, so using Arduino CLI's code for querying the
index should be safe and avoid the problems associated with the code duplication that would be the alternative.

Author: per1234

internal/project/projectdata/library.go

@@ -16,19 +16,20 @@
 package projectdata
 
 import (
-	"encoding/json"
-	"io/ioutil"
+	"io"
 	"net/http"
 	"os"
 
 	"github.com/arduino/arduino-cli/arduino/libraries"
+	"github.com/arduino/arduino-cli/arduino/libraries/librariesmanager"
 	"github.com/arduino/arduino-lint/internal/configuration"
 	"github.com/arduino/arduino-lint/internal/configuration/rulemode"
 	"github.com/arduino/arduino-lint/internal/project"
 	"github.com/arduino/arduino-lint/internal/project/library/libraryproperties"
 	"github.com/arduino/arduino-lint/internal/result/feedback"
 	"github.com/arduino/arduino-lint/internal/rule/schema"
 	"github.com/arduino/arduino-lint/internal/rule/schema/compliancelevel"
+	"github.com/arduino/go-paths-helper"
 	"github.com/arduino/go-properties-orderedmap"
 	"github.com/client9/misspell"
 	"github.com/sirupsen/logrus"
@@ -60,23 +61,34 @@ func InitializeForLibrary(project project.Type) {
 
 	// Download the Library Manager index if needed.
 	if !configuration.RuleModes(project.SuperprojectType)[rulemode.LibraryManagerIndexing] && libraryManagerIndex == nil {
-		url := "http://downloads.arduino.cc/libraries/library_index.json"
-		httpResponse, err := http.Get(url)
+		// Set up the temporary folder for the index
+		libraryIndexFolderPath, err := paths.TempDir().MkTempDir("arduino-lint-library-index-folder")
+		defer libraryIndexFolderPath.RemoveAll()
 		if err != nil {
-			feedback.Errorf("Unable to download Library Manager index from %s: %s", err, url)
+			panic(err)
+		}
+		libraryIndexPath := libraryIndexFolderPath.Join("library_index.json")
+
+		// Download the index data
+		httpResponse, err := http.Get(librariesmanager.LibraryIndexURL.String())
+		if err != nil {
+			feedback.Errorf("Unable to download Library Manager index from %s: %s", err, librariesmanager.LibraryIndexURL)
 			os.Exit(1)
 		}
 		defer httpResponse.Body.Close()
 
-		bytes, err := ioutil.ReadAll(httpResponse.Body)
+		// Write the index data to file
+		libraryIndexFile, err := libraryIndexPath.Create()
+		defer libraryIndexFile.Close()
 		if err != nil {
 			panic(err)
 		}
-
-		err = json.Unmarshal(bytes, &libraryManagerIndex)
-		if err != nil {
+		if _, err := io.Copy(libraryIndexFile, httpResponse.Body); err != nil {
 			panic(err)
 		}
+
+		libraryManagerIndex = librariesmanager.NewLibraryManager(libraryIndexFolderPath, nil)
+		libraryManagerIndex.LoadIndex()
 	}
 
 	if misspelledWordsReplacer == nil { // The replacer only needs to be compiled once per run.
@@ -120,10 +132,10 @@ func SourceHeaders() []string {
 	return sourceHeaders
 }
 
-var libraryManagerIndex map[string]interface{}
+var libraryManagerIndex *librariesmanager.LibrariesManager
 
 // LibraryManagerIndex returns the Library Manager index data.
-func LibraryManagerIndex() map[string]interface{} {
+func LibraryManagerIndex() *librariesmanager.LibrariesManager {
 	return libraryManagerIndex
 }
 

internal/rule/rulefunction/library.go

@@ -1461,15 +1461,8 @@ func IncorrectExamplesFolderNameCase() (result ruleresult.Type, output string) {
 
 // nameInLibraryManagerIndex returns whether there is a library in Library Manager index using the given name.
 func nameInLibraryManagerIndex(name string) bool {
-	libraries := projectdata.LibraryManagerIndex()["libraries"].([]interface{})
-	for _, libraryInterface := range libraries {
-		library := libraryInterface.(map[string]interface{})
-		if library["name"].(string) == name {
-			return true
-		}
-	}
-
-	return false
+	library := projectdata.LibraryManagerIndex().Index.FindIndexedLibrary(&libraries.Library{Name: name})
+	return library != nil
 }
 
 // spellCheckLibraryPropertiesFieldValue returns the value of the provided library.properties field with commonly misspelled words corrected.