如何将 json gzip 文件解组为结构

Question

我正在编写一个 trie DS，将 json gzip 压缩到一个文件中trieSample.json.gz，然后将其读回结构中。奇怪的是，解组成功但结构未填充。

我试过 json.Unmarshal 和 json.Decoder 都无济于事。需要帮助找到我在这里缺少的东西。读取时不会抛出任何错误，只是该结构没有任何键。如果我尝试正常的 json marshal -> 写入文件并从文件读取 -> Unmarshal，它会正常工作。

var charSet = "0123456789bcdefghjkmnopqrstuvwxyz"

const logTagSlice = "trie.log"

type trieSlice struct {

    Children []*tNode          `json:"c"`

    Charset  map[int32]int8    `json:"l"` // Charset is the legend of what charset is used to create the keys and how to position them in trie array

    logger   loggingapi.Logger `json:"-"`

    capacity int               `json:"-"` // capacity is the slice capacity to have enough to hold all the characters in the charset

}

type tNode struct {

    Children []*tNode `json:"c"`           // children represents the next valid runes AFTER the current one

    IsLeaf   bool     `json:"e,omitempty"` // isLeaf represents if this node represents the end of a valid word

    Value    int16    `json:"v,omitempty"` // value holds the corresponding value for key value pair, where key is the whole tree of nodes starting from parent representing a valid word

}

// NewTrieSlice returns a Trie, charset represents how the children need to be positioned in the array

func NewTrieSlice(charset string, logger loggingapi.Logger) *trieSlice {

    m := map[int32]int8{}

    for index, r := range charset {

        m[r] = int8(index)

    }

    return &trieSlice{

        Charset:  m,

        Children: make([]*tNode, len(charset)),

        logger:   logger,

        capacity: len(charset),

    }

}

func newNode(capacity int) *tNode {

    return &tNode{

        Children: make([]*tNode, capacity),

    }

}

spew.Dump 显示 trieSlice Children 数组包含所有 nil 元素

Answer 1

在使用数据之前关闭压缩机。使用前先解压数据。不要因不当使用 bufio.Scanner 而将其砍掉。var network bytes.Bufferb, err := json.Marshal(trie)if err != nil {    fmt.Println("error in marshal ... ", err.Error())    t.Fail()}w := gzip.NewWriter(&network)w.Write(b)w.Close()err = ioutil.WriteFile("trieSample.json.gz", network.Bytes(), 0644)if err != nil {    log.Fatal(err)}trieDecoder := NewTrieSlice(charSet)// attempt via json Unmarshalfile, err := os.Open("trieSample.json.gz")if err != nil {    log.Fatal(err)}r, err := gzip.NewReader(file)if err != nil {    log.Fatal(err)}err = json.NewDecoder(r).Decode(trieDecoder)if err != nil {    log.Fatal(err)}spew.Dump(trieDecoder)https://play.golang.org/p/pYup3v8-f4c