前言
在开发过程中，我们经常会用到网络请求，在flutter框架中，dio框架非常不错，所以今天的文章在dio的基础上搭建一套网络持久化框架，那么在flutter项目中如何搭建一套，高可用性，维护性较高的dio公共请求参数框架呢？
搭建前夕准备
一、基本认知
- 要持久化那么必然要有存储设备
- 持久化的数据在app启动后要即使填充到项目中
- 由于项目中网络请求地址繁多，类型不同，需要持久化的位置不同
二、基于基本认知来找合适的工具&必要点
2.1 持久化的工具：
我的推荐
- mmkv
- share_prefresence
今天主要用讲解mmkv版本
2.2必要点：
dio拦截器
拦截器是搭建这套持久化的关键
三、准备好如上技能，我们来搭建这套持久化网络框架吧
1、首先要知道有几种类型的公共
//请求中url后追加公共请求
static const int urlPresistent = 1;
//请求头中追加公共请求
static const int headerPresistent = 2;
//全部都追加公共请求
static const int allPresistent = 3;
2、构建缓存参数（为了快速获取）
static Map<String,Map<String, String?>> headerPersistent = Map();
static Map<String,Map<String, String?>> urlPersistent = Map();
3、构建mmkv存储结构（加密存储）
static MMKV _store(String baseUrl, int type) => MMKVStore.sysSafeMMKV(name: '${SysConfig.sysPersistent}${baseUrl}_${type.toString()}');
4、构建基本函数
单健值对存储
static void setPersistent(String baseUrl,String key,String? value,{int type = allPresistent}){
if (type == allPresistent || type == headerPresistent) {
if (!headerPersistent.containsKey(baseUrl)) {
headerPersistent[baseUrl] = Map<String, String?>();
}
var keyMap = headerPersistent[baseUrl]!;
keyMap[key] = value;
_store(baseUrl, headerPresistent).encodeString(key, value??"");
}
if (type == allPresistent || type == urlPresistent) {
if (!urlPersistent.containsKey(baseUrl)) {
urlPersistent[baseUrl] = Map<String, String?>();
}
var keyMap = urlPersistent[baseUrl]!;
keyMap[key] = value;
_store(baseUrl, urlPresistent).encodeString(key, value??"");
}
}
多健值对存储
static void setPersistentMap(String baseUrl,Map<String, String?> map,{int type = allPresistent}){
if (type == allPresistent || type == headerPresistent) {
if (!headerPersistent.containsKey(baseUrl)) {
headerPersistent[baseUrl] = Map<String, String?>();
}
var keyMap = headerPersistent[baseUrl]!;
keyMap.addAll(map);
keyMap.forEach((key, value) {
_store(baseUrl, headerPresistent).encodeString(key, value??"");
});
}
if (type == allPresistent || type == urlPresistent) {
if (!urlPersistent.containsKey(baseUrl)) {
urlPersistent[baseUrl] = Map<String, String?>();
}
var keyMap = urlPersistent[baseUrl]!;
keyMap.addAll(map);
keyMap.forEach((key, value) {
_store(baseUrl, urlPresistent).encodeString(key, value??"");
});
}
}
参数获取：
static Map<String, String?>? getPersistent(String baseUrl, {int type = allPresistent}) {
Map<String, String?>? map;
if (type == allPresistent || type == headerPresistent) {
Map<String, String?>? headerMap;
if (headerPersistent.containsKey(baseUrl)) {
headerMap = headerPersistent[baseUrl];
} else {
headerMap = null;
}
if (headerMap != null) {
if (map == null) {
map = Map();
}
map.addAll(headerMap);
}
}
if (type == allPresistent || type == urlPresistent) {
Map<String, String?>? urlMap;
if (urlPersistent.containsKey(baseUrl)) {
urlMap = urlPersistent[baseUrl];
} else {
urlMap = null;
}
if (urlMap != null) {
if (map == null) {
map = Map();
}
map.addAll(urlMap);
}
}
return map;
}
刷新当前缓存（应用启动刷新）
static Map<String, String?> _all(String baseurl, int type) {
var mmkv= _store(baseurl, type);
var keys = mmkv.allKeys;
var map = Map<String, String?>();
keys.forEach((element) {
var value = mmkv.decodeString(element);
map[element] = value;
});
return map;
}
static void flushPersistent(String baseurl, {int type = allPresistent}) {
if (type == allPresistent || type == headerPresistent) {
var map = _all(baseurl, headerPresistent);
headerPersistent[baseurl]?.clear();
if (!headerPersistent.containsKey(baseurl)) {
headerPersistent[baseurl] = Map<String, String?>();
}
var keyMap = headerPersistent[baseurl]!;
keyMap.addAll(map);
}
if (type == allPresistent || type == urlPresistent) {
var map = _all(baseurl, urlPresistent);
urlPersistent[baseurl]?.clear();
if (!urlPersistent.containsKey(baseurl)) {
urlPersistent[baseurl] = Map<String, String?>();
}
var keyMap = urlPersistent[baseurl]!;
keyMap.addAll(map);
}
}
退出登陆移除持久化
static void removeAllPersistent(String baseurl, {int type = allPresistent}) {
if (type == allPresistent || type == headerPresistent) {
headerPersistent[baseurl]?.clear();
_store(baseurl, headerPresistent).clearAll();
}
if (type == allPresistent || type == urlPresistent) {
urlPersistent[baseurl]?.clear();
_store(baseurl, urlPresistent).clearAll();
}
}
拦截器实现（dio请求拦截管理）
class PresistentInterceptor extends Interceptor {
@override
void onRequest(RequestOptions options, RequestInterceptorHandler handler) {
var urlPersitents = HttpPersistent.getPersistent(options.baseUrl,type: HttpPersistent.urlPresistent);
var headerPersitents = HttpPersistent.getPersistent(options.baseUrl,
type: HttpPersistent.headerPresistent);
headerPersitents?.forEach((key, value) {
options.headers[key] = value;
});
urlPersitents?.forEach((key, value) {
options.queryParameters[key] = value;
});
super.onRequest(options, handler);
}
}
四、整体代码&事件调用逻辑
整体代码
class HttpPersistent{
static const int urlPresistent = 1;
static const int headerPresistent = 2;
static const int allPresistent = 3;
static MMKV _store(String baseUrl, int type) => MMKVStore.sysSafeMMKV(name: '${SysConfig.sysPersistent}${baseUrl}_${type.toString()}');
static Map<String,Map<String, String?>> headerPersistent = Map();
static Map<String,Map<String, String?>> urlPersistent = Map();
static void setPersistent(String baseUrl,String key,String? value,{int type = allPresistent}){
if (type == allPresistent || type == headerPresistent) {
if (!headerPersistent.containsKey(baseUrl)) {
headerPersistent[baseUrl] = Map<String, String?>();
}
var keyMap = headerPersistent[baseUrl]!;
keyMap[key] = value;
_store(baseUrl, headerPresistent).encodeString(key, value??"");
}
if (type == allPresistent || type == urlPresistent) {
if (!urlPersistent.containsKey(baseUrl)) {
urlPersistent[baseUrl] = Map<String, String?>();
}
var keyMap = urlPersistent[baseUrl]!;
keyMap[key] = value;
_store(baseUrl, urlPresistent).encodeString(key, value??"");
}
}
static void setPersistentMap(String baseUrl,Map<String, String?> map,{int type = allPresistent}){
if (type == allPresistent || type == headerPresistent) {
if (!headerPersistent.containsKey(baseUrl)) {
headerPersistent[baseUrl] = Map<String, String?>();
}
var keyMap = headerPersistent[baseUrl]!;
keyMap.addAll(map);
keyMap.forEach((key, value) {
_store(baseUrl, headerPresistent).encodeString(key, value??"");
});
}
if (type == allPresistent || type == urlPresistent) {
if (!urlPersistent.containsKey(baseUrl)) {
urlPersistent[baseUrl] = Map<String, String?>();
}
var keyMap = urlPersistent[baseUrl]!;
keyMap.addAll(map);
keyMap.forEach((key, value) {
_store(baseUrl, urlPresistent).encodeString(key, value??"");
});
}
}
static Map<String, String?>? getPersistent(String baseUrl, {int type = allPresistent}) {
Map<String, String?>? map;
if (type == allPresistent || type == headerPresistent) {
Map<String, String?>? headerMap;
if (headerPersistent.containsKey(baseUrl)) {
headerMap = headerPersistent[baseUrl];
} else {
headerMap = null;
}
if (headerMap != null) {
if (map == null) {
map = Map();
}
map.addAll(headerMap);
}
}
if (type == allPresistent || type == urlPresistent) {
Map<String, String?>? urlMap;
if (urlPersistent.containsKey(baseUrl)) {
urlMap = urlPersistent[baseUrl];
} else {
urlMap = null;
}
if (urlMap != null) {
if (map == null) {
map = Map();
}
map.addAll(urlMap);
}
}
return map;
}
static Map<String, String?> _all(String baseurl, int type) {
var mmkv= _store(baseurl, type);
var keys = mmkv.allKeys;
var map = Map<String, String?>();
keys.forEach((element) {
var value = mmkv.decodeString(element);
map[element] = value;
});
return map;
}
static void flushPersistent(String baseurl, {int type = allPresistent}) {
if (type == allPresistent || type == headerPresistent) {
var map = _all(baseurl, headerPresistent);
headerPersistent[baseurl]?.clear();
if (!headerPersistent.containsKey(baseurl)) {
headerPersistent[baseurl] = Map<String, String?>();
}
var keyMap = headerPersistent[baseurl]!;
keyMap.addAll(map);
}
if (type == allPresistent || type == urlPresistent) {
var map = _all(baseurl, urlPresistent);
urlPersistent[baseurl]?.clear();
if (!urlPersistent.containsKey(baseurl)) {
urlPersistent[baseurl] = Map<String, String?>();
}
var keyMap = urlPersistent[baseurl]!;
keyMap.addAll(map);
}
}
static void removeAllPersistent(String baseurl, {int type = allPresistent}) {
if (type == allPresistent || type == headerPresistent) {
headerPersistent[baseurl]?.clear();
_store(baseurl, headerPresistent).clearAll();
}
if (type == allPresistent || type == urlPresistent) {
urlPersistent[baseurl]?.clear();
_store(baseurl, urlPresistent).clearAll();
}
}
}
class PresistentInterceptor extends Interceptor {
@override
void onRequest(RequestOptions options, RequestInterceptorHandler handler) {
var urlPersitents = HttpPersistent.getPersistent(options.baseUrl,type: HttpPersistent.urlPresistent);
var headerPersitents = HttpPersistent.getPersistent(options.baseUrl,
type: HttpPersistent.headerPresistent);
headerPersitents?.forEach((key, value) {
options.headers[key] = value;
});
urlPersitents?.forEach((key, value) {
options.queryParameters[key] = value;
});
super.onRequest(options, handler);
}
}
1、登陆后，调用存储
HttpPersistent.setPersistent("http://www.baidu.com","token","123",HttpPersistent.headerPresistent)
2、退出登陆后，调用移除
HttpPersistent.removeAllPersistent("http://www.baidu.com",,type: HttpPersistent.headerPresistent);
3、应用启动后刷新缓存
HttpPersistent.flushPersistent("http://www.baidu.com",
type: HttpPersistent.headerPresistent);
五、大功告成
如上就构建出一套可靠性高，维护性高的网络持久化框架
更多flutter教程请关注我的IMGeek：https://www.imgeek.org/people/33692
