CI: Fix golangci-lint linter issues, add prealloc linter and bump version depends for Go 1.18 (#915)

* Bump CI versions

* Specifically set go version as 1.17.x bumps it to 1.18

* Another

* Adjust AppVeyor

* Part 1 of linter issues

* Part 2

* Fix various linters and improvements

* Part 3

* Finishing touches

* Tests and EqualFold

* Fix nitterinos plus bonus requester jobs bump for exchanges with large number of tests

* Fix nitterinos and bump golangci-lint timeout for AppVeyor

* Address nits, ensure all books are returned on err due to syncer regression

* Fix the wiggins

* Fix duplication

* Fix nitterinos

exchanges/mock/common.go

@@ -42,7 +42,7 @@ func MatchURLVals(v1, v2 url.Values) bool {
 // DeriveURLValsFromJSONMap gets url vals from a map[string]string encoded JSON body
 func DeriveURLValsFromJSONMap(payload []byte) (url.Values, error) {
 	var vals = url.Values{}
-	if string(payload) == "" {
+	if len(payload) == 0 {
 		return vals, nil
 	}
 	intermediary := make(map[string]interface{})

exchanges/mock/recording.go

@@ -4,7 +4,7 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"net/http"
 	"net/url"
 	"os"
@@ -48,7 +48,7 @@ func HTTPRecord(res *http.Response, service string, respContents []byte) error {
 
 	fileout := filepath.Join(DefaultDirectory, service, service+".json")
 
-	contents, err := ioutil.ReadFile(fileout)
+	contents, err := os.ReadFile(fileout)
 	if err != nil {
 		return err
 	}
@@ -80,7 +80,7 @@ func HTTPRecord(res *http.Response, service string, respContents []byte) error {
 		if bodyErr != nil {
 			return bodyErr
 		}
-		payload, bodyErr := ioutil.ReadAll(bodycopy)
+		payload, bodyErr := io.ReadAll(bodycopy)
 		if bodyErr != nil {
 			return bodyErr
 		}
@@ -298,11 +298,10 @@ const (
 
 // CheckJSON recursively parses json data to retract keywords, quite intensive.
 func CheckJSON(data interface{}, excluded *Exclusion) (interface{}, error) {
-	var context map[string]interface{}
-	if reflect.TypeOf(data).String() == "[]interface {}" {
+	if d, ok := data.([]interface{}); ok {
 		var sData []interface{}
-		for i := range data.([]interface{}) {
-			v := data.([]interface{})[i]
+		for i := range d {
+			v := d[i]
 			switch v.(type) {
 			case map[string]interface{}, []interface{}:
 				checkedData, err := CheckJSON(v, excluded)
@@ -324,6 +323,7 @@ func CheckJSON(data interface{}, excluded *Exclusion) (interface{}, error) {
 		return nil, err
 	}
 
+	var context map[string]interface{}
 	err = json.Unmarshal(conv, &context)
 	if err != nil {
 		return nil, err
@@ -426,7 +426,7 @@ func GetExcludedItems() (Exclusion, error) {
 	m.Lock()
 	defer m.Unlock()
 	if !set {
-		file, err := ioutil.ReadFile(exclusionFile)
+		file, err := os.ReadFile(exclusionFile)
 		if err != nil {
 			if !strings.Contains(err.Error(), "no such file or directory") {
 				return excludedList, err
@@ -440,7 +440,7 @@ func GetExcludedItems() (Exclusion, error) {
 				return excludedList, mErr
 			}
 
-			mErr = ioutil.WriteFile(exclusionFile, data, os.ModePerm)
+			mErr = os.WriteFile(exclusionFile, data, os.ModePerm)
 			if mErr != nil {
 				return excludedList, mErr
 			}

exchanges/mock/server.go

@@ -4,11 +4,12 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"log"
 	"net/http"
 	"net/http/httptest"
 	"net/url"
+	"os"
 	"reflect"
 	"strconv"
 	"strings"
@@ -42,7 +43,7 @@ func NewVCRServer(path string) (string, *http.Client, error) {
 
 	var mockFile VCRMock
 
-	contents, err := ioutil.ReadFile(path)
+	contents, err := os.ReadFile(path)
 	if err != nil {
 		pathing := strings.Split(path, "/")
 		dirPathing := pathing[:len(pathing)-1]
@@ -126,7 +127,7 @@ func RegisterHandler(pattern string, mock map[string][]HTTPResponse, mux *http.S
 		case http.MethodPost, http.MethodPut:
 			switch r.Header.Get(contentType) {
 			case applicationURLEncoded:
-				readBody, err := ioutil.ReadAll(r.Body)
+				readBody, err := io.ReadAll(r.Body)
 				if err != nil {
 					log.Fatal("Mock Test Failure - ReadAll error", err)
 				}
@@ -154,7 +155,7 @@ func RegisterHandler(pattern string, mock map[string][]HTTPResponse, mux *http.S
 				return
 
 			case applicationJSON:
-				readBody, err := ioutil.ReadAll(r.Body)
+				readBody, err := io.ReadAll(r.Body)
 				if err != nil {
 					log.Fatalf("Mock Test Failure - %v", err)
 				}

exchanges/mock/server_test.go

@@ -4,7 +4,6 @@ import (
 	"bytes"
 	"context"
 	"encoding/json"
-	"io/ioutil"
 	"net/http"
 	"os"
 	"strings"
@@ -48,7 +47,7 @@ func TestNewVCRServer(t *testing.T) {
 		t.Fatal("marshal error", err)
 	}
 
-	err = ioutil.WriteFile(testFile, payload, os.ModePerm)
+	err = os.WriteFile(testFile, payload, os.ModePerm)
 	if err != nil {
 		t.Fatal("marshal error", err)
 	}