com.hxl.miniapi.http.MultipartParser.kt Maven / Gradle / Ivy
package com.hxl.miniapi.http
import com.hxl.miniapi.core.exception.ClientException
import com.hxl.miniapi.http.file.FilePart
import com.hxl.miniapi.utils.startWhithPlus
import java.io.ByteArrayInputStream
import java.io.ByteArrayOutputStream
import java.util.regex.Matcher
import java.util.regex.Pattern
class MultipartParser(private val requestBody: ByteArray, private val boundary: String) {
private val data = parser(requestBody)
companion object {
const val FILENAME_KEY = "filename"
const val NAME_KEY = "name"
const val CONTENT_TYPE = "Content-Type"
const val CONTENT_DISPOSITION = "Content-Disposition"
}
fun getFiles(): MutableList {
return data.values.filterIsInstance().toCollection(mutableListOf())
}
fun getPropertys(): MutableMap {
val result = mutableMapOf()
data.forEach { (key, value) -> if (value is String) result[key] = value }
return result
}
private fun parser(bodyByte: ByteArray): MutableMap {
if (bodyByte.isEmpty()) throw ClientException.create400("客户端请求错误")
val lineInputStream = LineInputStream(bodyByte, boundary)
val result = mutableMapOf()
while (lineInputStream.readLine()?.also {
if (it.decodeToString() != boundary) {
//如果是结束标志
if (it.decodeToString() == "${boundary}--") return@also
//不是结束标志也不是开始标志
throw ClientException.create400("客户端请求错误")
}
val property = mutableMapOf()
while (!lineInputStream.nextIs("\r\n")) {
property.putAll(findDisposition(lineInputStream.readLine()!!.decodeToString()))
}
//跳过属性
lineInputStream.skip(2)
val keyValue = lineInputStream.readValue()
//如果是文件
if (property.containsKey(FILENAME_KEY)) {
result[property[NAME_KEY]!!] = FilePart().apply {
this.name = property[NAME_KEY]!!
this.contentType = property[CONTENT_TYPE]!!
this.inputStream = ByteArrayInputStream(keyValue)
this.contentTypeLength = keyValue.size.toLong()
}
} else {
result[property[NAME_KEY]!!] = keyValue.decodeToString()
}
} != null) {
}
return result
}
/**
* @description: 解析描述字符
* @date: 2022/10/4 下午7:54
*/
private fun findDisposition(source: String): MutableMap {
val nameRegex: Matcher = Pattern.compile("[^file]name=\"(.*?)\"").matcher(source)
val fileNameRegex = Pattern.compile("filename=\"(.*)\"").matcher(source)
val result = mutableMapOf()
if (source.startWhithPlus("$CONTENT_DISPOSITION:") && nameRegex.find()) {
result[NAME_KEY] = nameRegex.group(1)
}
if (source.startWhithPlus("$CONTENT_DISPOSITION:") && fileNameRegex.find()) {
result[FILENAME_KEY] = fileNameRegex.group(1)
}
if (source.startWhithPlus(CONTENT_TYPE)) {
result[CONTENT_TYPE] = source.substring("$CONTENT_TYPE:".length).trim()
}
return result
}
class LineInputStream(private val bodyByte: ByteArray, private val boundary: String) {
private var offset: Int = 0
fun readLine(): ByteArray? {
val arrayOutputStream = ByteArrayOutputStream()
while (offset < bodyByte.size && bodyByte[offset++] != '\r'.code.toByte()) {
arrayOutputStream.write(bodyByte[offset - 1].toInt())
}
moveToNext()
if (arrayOutputStream.toByteArray().isEmpty()) return null
return arrayOutputStream.toByteArray()
}
fun readValue(): ByteArray {
val arrayOutputStream = ByteArrayOutputStream()
nextPartPostion().run {
for (i in offset until this - 2) {
arrayOutputStream.write(bodyByte[i].toInt())
}
offset = this
}
return arrayOutputStream.toByteArray()
}
fun nextIs(target: String): Boolean {
val arrayOutputStream = ByteArrayOutputStream()
for (i in offset until offset + target.length) {
arrayOutputStream.write(bodyByte[i].toInt())
}
return arrayOutputStream.toByteArray().decodeToString() == target
}
private fun nextPartPostion(): Int {
var tempOffset = this.offset
val arrayOutputStream = ByteArrayOutputStream()
while (arrayOutputStream.toByteArray().decodeToString() != boundary) {
//如果当前位置+boundary.length还没超出范围
arrayOutputStream.reset()
if (tempOffset + boundary.length > bodyByte.size) throw ClientException.create400("客户端请求错误")
//取这个阶段的范围
for (i in tempOffset until tempOffset + boundary.length) {
arrayOutputStream.write(bodyByte[i].toInt())
}
tempOffset++
}
//返回下一个item开始的位置，但包含\r\n需要去除
return tempOffset - 1
}
private fun moveToNext() {
while (offset < bodyByte.size && bodyByte[offset++] != '\n'.code.toByte()) { }
}
fun skip(i: Int) {
offset += i
}
}
}