Method PrepareCache

internal/nodes/http_writer.go:158–509

PrepareCache 准备缓存

(resp *http.Response, size int64)

// PrepareCache 准备缓存
func (this *HTTPWriter) PrepareCache(resp *http.Response, size int64) {
	if resp == nil {
		return
	}

	var cachePolicy = this.req.ReqServer.HTTPCachePolicy
	if cachePolicy == nil || !cachePolicy.IsOn {
		return
	}

	var cacheRef = this.req.cacheRef
	if cacheRef == nil || !cacheRef.IsOn {
		return
	}

	var addStatusHeader = this.req.web != nil && this.req.web.Cache != nil && this.req.web.Cache.AddStatusHeader

	// 不支持Range
	if this.isPartial {
		if !cacheRef.AllowPartialContent {
			this.req.varMapping["cache.status"] = "BYPASS"
			if addStatusHeader {
				this.Header().Set("X-Cache", "BYPASS, not supported partial content")
			}
			return
		}
		if this.cacheStorage.Policy().Type != serverconfigs.CachePolicyStorageFile {
			this.req.varMapping["cache.status"] = "BYPASS"
			if addStatusHeader {
				this.Header().Set("X-Cache", "BYPASS, not supported partial content in memory storage")
			}
			return
		}
	}

	// 如果允许 ChunkedEncoding，就无需尺寸的判断，因为此时的 size 为 -1
	if !cacheRef.AllowChunkedEncoding && size < 0 {
		this.req.varMapping["cache.status"] = "BYPASS"
		if addStatusHeader {
			this.Header().Set("X-Cache", "BYPASS, ChunkedEncoding")
		}
		return
	}

	var contentSize = size
	if this.isPartial {
		// 从Content-Range中读取内容总长度
		var contentRange = this.Header().Get("Content-Range")
		_, totalSize := httpRequestParseContentRangeHeader(contentRange)
		if totalSize > 0 {
			contentSize = totalSize
		}
	}
	if contentSize >= 0 && ((cacheRef.MaxSizeBytes() > 0 && contentSize > cacheRef.MaxSizeBytes()) ||
		(cachePolicy.MaxSizeBytes() > 0 && contentSize > cachePolicy.MaxSizeBytes()) || (cacheRef.MinSizeBytes() > contentSize)) {
		this.req.varMapping["cache.status"] = "BYPASS"
		if addStatusHeader {
			this.Header().Set("X-Cache", "BYPASS, Content-Length")