前言
有时候我们需要为app中的http网络请求添加一些通用参数,比如当前应用版本、某些key值等,一般来说我们都会使用OkHttp的拦截器进行操作,所以下面就简单介绍下如何实现
实现
首先我们得知道参数一般都在哪里。对于GET请求,参数一般是拼接在url的后面,对于POST请求则分为两种。一种是表单提交,一种是参数Body中提交,对于参数在Body中的,我们暂时不考虑,因为判断有点困难。
对于GET请求,我们直接拼接到Url的后面,需要注意的是:我们需要删除同名的参数,不然如果外面也传递了通用参数,那么后台会将此字段的value使用逗号拼接在一起。(类似于version=1.1.1,1.2.2)
private static final Map sCommonParams = new HashMap<>();
private Request injectParamsIntoUrl(Request request) {
Request.Builder requestBuilder = request.newBuilder();
HttpUrl.Builder httpUrlBuilder = request.url().newBuilder();
for (Map.Entry entry : sCommonParams.entrySet()) {
httpUrlBuilder.removeAllQueryParameters(entry.getKey());
httpUrlBuilder.addQueryParameter(entry.getKey(), entry.getValue());
}
requestBuilder.url(httpUrlBuilder.build());
return requestBuilder.build();
}
对于POST请求,我们先加入通用参数,然后将原始请求中的非通用参数添加进去即可。
这里有个小问题:就是如果我们需要将参数进行编码,那么我们需要使用builder.addEncoded("name",""value"),当然,我们也可以从原始请求中获取到编码后的参数formBody.encodedName()/formBody.encodedValue()
@Nullable
private Request injectParamsIntoForm(Request request) {
RequestBody body = request.body();
if (body instanceof FormBody) {
FormBody formBody = (FormBody) body;
FormBody.Builder builder = new FormBody.Builder();
//加入通用参数
for (Map.Entry entry : sCommonParams.entrySet()) {
builder.add(entry.getKey(), entry.getValue());
}
//加入非通用参数
for (int i = 0; i < formBody.size(); i++) {
if (!sCommonParams.containsKey(formBody.name(i))) {
builder.add(formBody.name(i), formBody.value(i));
}
}
return request.newBuilder()
.post(builder.build())
.build();
}
return null;
}
上面我们已经针对GET以及POST都进行了处理,下面贴出全部的代码,当发现POST没有使用Form提交参数时,直接注入到URL的后面
public static class CommonRequestParameterInterceptor implements Interceptor {
private static final String TAG = "CommonRequestParameterI";
private static final Map sCommonParams = new HashMap<>();
public CommonRequestParameterInterceptor() {
sCommonParams.put("version", String.valueOf(AppApplicationMgr.getVersionCode(ContextUtils.getAppContext())));
sCommonParams.put("clientOsType", String.valueOf(Contracts.OS_ANDROID));
sCommonParams.put("sn", BuildConfig.SN);
sCommonParams.put("deviceId", DeviceUtils.getDeviceId());
sCommonParams.put("appKey", BuildConfig.APP_KEY);
}
@Override
public Response intercept(Chain chain) throws IOException {
Request request = chain.request();
String method = request.method();
if ("GET".equalsIgnoreCase(method)) {
//注入到url
request = injectParamsIntoUrl(request);
} else if ("POST".equalsIgnoreCase(method)) {
//注入到body
Request paramsIntoForm = injectParamsIntoForm(request);
if (paramsIntoForm != null) {
request = paramsIntoForm;
} else {
//如果body注入不了,则尝试注入url
request = injectParamsIntoUrl(request);
}
}
return chain.proceed(request);
}
private Request injectParamsIntoUrl(Request request) {
Request.Builder requestBuilder = request.newBuilder();
HttpUrl.Builder httpUrlBuilder = request.url().newBuilder();
for (Map.Entry entry : sCommonParams.entrySet()) {
httpUrlBuilder.removeAllQueryParameters(entry.getKey());
httpUrlBuilder.addQueryParameter(entry.getKey(), entry.getValue());
}
requestBuilder.url(httpUrlBuilder.build());
return requestBuilder.build();
}
@Nullable
private Request injectParamsIntoForm(Request request) {
RequestBody body = request.body();
if (body instanceof FormBody) {
FormBody formBody = (FormBody) body;
FormBody.Builder builder = new FormBody.Builder();
//加入通用参数
for (Map.Entry entry : sCommonParams.entrySet()) {
builder.add(entry.getKey(), entry.getValue());
}
//加入非通用参数
for (int i = 0; i < formBody.size(); i++) {
if (!sCommonParams.containsKey(formBody.name(i))) {
builder.add(formBody.name(i), formBody.value(i));
}
}
return request.newBuilder()
.post(builder.build())
.build();
}
return null;
}
}