This feature allows you to configure some defaults for all the requests for a specific client.
io.ktor.client.features.defaultRequest 方法中定义，无需任何额外构件。
When configuring the client, there is an extension method provided by this feature to set come defaults for this client. For example, if you want to add a header to all the requests, or configure the host, port, and method or just set the path.
val client = HttpClient() {
defaultRequest { // this: HttpRequestBuilder ->
method = HttpMethod.Head
host = "127.0.0.1"
port = 8080
header("X-My-Header", "MyValue")
}
}
An example showing how to the client behaves using the MockEngine:
import io.ktor.client.*
import io.ktor.client.engine.*
import io.ktor.client.engine.mock.*
import io.ktor.client.features.*
import io.ktor.client.request.*
import io.ktor.http.*
import kotlinx.coroutines.experimental.*
import kotlinx.coroutines.experimental.io.*
fun main(args: Array<String>) = runBlocking {
val client = HttpClient(MockEngine) {
engine {
// Register request handler.
addHandler { request ->
with(request) {
val responseText = buildString{
append("method=$method,")
append("host=${url.host},")
append("port=${url.port},")
append("path=${url.fullPath},")
append("headers=$headers")
}
val responseHeaders = headersOf("Content-Type" to listOf(ContentType.Text.Plain.toString()))
respond(responseText, headers = responseHeaders)
}
}
}
// Configure default request feature.
defaultRequest {
method = HttpMethod.Head
host = "127.0.0.1"
port = 8080
header("X-My-Header", "MyValue")
}
}
val result = client.get<String> {
url {
encodedPath = "/demo"
}
}
println(result)
// Prints: method=HttpMethod(value=HEAD), host=127.0.0.1, port=8080, path=/demo, headers=Headers [X-My-Header=[MyValue], Accept=[*/*]]
}