Update README.md

Author: rbygrave

README.md

@@ -1 +1,112 @@
-# avaje-http-client
+# avaje-http-client
+
+Create a HttpClientContext with a baseUrl, Jackson or Gson based JSON
+ body adapter, logger.
+
+```java
+  public HttpClientContext client() {
+    return HttpClientContext.newBuilder()
+      .withBaseUrl(baseUrl)
+      .withResponseListener(new RequestLogger())
+      .withBodyAdapter(new JacksonBodyAdapter(new ObjectMapper()))
+//      .withBodyAdapter(new GsonBodyAdapter(new Gson()))
+      .build();
+  }
+
+```
+
+From HttpClientContext:
+ - Create a request
+ - Build the url via path(), matrixParam(), queryParam()
+ - Optionally set headers(), cookies() etc
+ - Optionally specify a request body (JSON, form, or raw BodyPublisher)
+ - Http verbs - get(), post(), put(), delete()
+ - Optionally return response body as a bean, list of beans, or raw
+
+## Examples
+
+GET as String
+```java
+    final HttpResponse<String> hres = clientContext.request()
+      .path("hello")
+      .get().asString();
+
+```
+
+GET as json to single bean
+```java
+final HelloDto bean = clientContext.request()
+  .path("hello/there")
+  .get().bean(HelloDto.class);
+```
+
+POST a bean as json request body
+```java
+HelloDto bean = new HelloDto(12, "rob", "other");
+
+final HttpResponse<Void> res = clientContext.request()
+  .path("hello/savebean")
+  .body(bean).post()
+  .asDiscarding();
+
+assertThat(res.statusCode()).isEqualTo(201);
+
+```
+
+GET as json to list of beans
+```java
+final List<HelloDto> beans = clientContext.request()
+  .path("hello")
+  .get().list(HelloDto.class);
+```
+
+Path
+```java
+final HttpResponse<String> res = clientContext.request()
+  .path("hello")
+  .path("withMatrix")
+  .path("2011")
+  .get().asString();
+
+// is the same as ...
+
+final HttpResponse<String> res = clientContext.request()
+  .path("hello/withMatrix/2011")
+  .get().asString();
+```
+
+MatrixParam
+```java
+final HttpResponse<String> httpRes = clientContext.request()
+  .path("hello")
+  .matrixParam("author", "rob")
+  .matrixParam("country", "nz")
+  .path("foo")
+  .matrixParam("extra", "banana")
+  .get().asString();
+```
+
+QueryParam
+```java
+final List<HelloDto> beans = clientContext.request()
+  .path("hello")
+  .queryParam("sortBy", "name")
+  .queryParam("maxCount", "100")
+  .get().list(HelloDto.class);
+```
+
+FormParam
+```java
+final HttpResponse<Void> res = clientContext.request()
+  .path("hello/saveform")
+  .formParam("name", "Bazz")
+  .formParam("email", "user@foo.com")
+  .formParam("url", "http://foo.com")
+  .formParam("startDate", "2020-12-03")
+  .post()
+  .asDiscarding();
+
+assertThat(res.statusCode()).isEqualTo(201);
+```
+
+## Currently NO support for POSTing multipart-form