-
Notifications
You must be signed in to change notification settings - Fork 2
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
- Loading branch information
Showing
4 changed files
with
173 additions
and
29 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,130 @@ | ||
| package backends | ||
|
|
||
| import ( | ||
| "encoding/base64" | ||
| "encoding/json" | ||
| "errors" | ||
| "fmt" | ||
| "io/ioutil" | ||
| "net/http" | ||
| "net/url" | ||
| "path" | ||
| "strconv" | ||
| ) | ||
|
|
||
| type TransactionOffset struct { | ||
| Size string `json:"size"` | ||
| Offset string `json:"offset"` | ||
| } | ||
|
|
||
| type TransactionChunk struct { | ||
| Chunk string `json:"chunk"` | ||
| DataPath string `json:"data_path"` | ||
| TxPath string `json:"tx_path"` | ||
| } | ||
|
|
||
| type Client struct { | ||
| client *http.Client | ||
| url string | ||
| } | ||
|
|
||
| func NewClient(nodeUrl string, proxyUrl ...string) *Client { | ||
| httpClient := http.DefaultClient | ||
| // if exist proxy url | ||
| if len(proxyUrl) > 0 { | ||
| pUrl := proxyUrl[0] | ||
| proxyUrl, err := url.Parse(pUrl) | ||
| if err != nil { | ||
| panic(err) | ||
| } | ||
| tr := &http.Transport{Proxy: http.ProxyURL(proxyUrl)} | ||
| httpClient = &http.Client{Transport: tr} | ||
| } | ||
|
|
||
| return &Client{client: httpClient, url: nodeUrl} | ||
| } | ||
|
|
||
| func (c *Client) getTransactionOffset(id string) (*TransactionOffset, error) { | ||
| _path := fmt.Sprintf("tx/%s/offset", id) | ||
| body, statusCode, err := c.httpGet(_path) | ||
| if statusCode != 200 { | ||
| return nil, errors.New("not found tx offset") | ||
| } | ||
| if err != nil { | ||
| return nil, err | ||
| } | ||
| txOffset := &TransactionOffset{} | ||
| if err := json.Unmarshal(body, txOffset); err != nil { | ||
| return nil, err | ||
| } | ||
| return txOffset, nil | ||
| } | ||
|
|
||
| func (c *Client) httpGet(_path string) (body []byte, statusCode int, err error) { | ||
| u, err := url.Parse(c.url) | ||
| if err != nil { | ||
| return | ||
| } | ||
|
|
||
| u.Path = path.Join(u.Path, _path) | ||
|
|
||
| resp, err := c.client.Get(u.String()) | ||
| if err != nil { | ||
| return | ||
| } | ||
| defer resp.Body.Close() | ||
|
|
||
| statusCode = resp.StatusCode | ||
| body, err = ioutil.ReadAll(resp.Body) | ||
| return | ||
| } | ||
|
|
||
| func (c *Client) DownloadChunkData(id string) ([]byte, error) { | ||
| offsetResponse, err := c.getTransactionOffset(id) | ||
| if err != nil { | ||
| return nil, err | ||
| } | ||
| size, err := strconv.ParseInt(offsetResponse.Size, 10, 64) | ||
| if err != nil { | ||
| return nil, err | ||
| } | ||
| endOffset, err := strconv.ParseInt(offsetResponse.Offset, 10, 64) | ||
| if err != nil { | ||
| return nil, err | ||
| } | ||
| startOffset := endOffset - size + 1 | ||
| data := make([]byte, 0, size) | ||
| for i := 0; int64(i)+startOffset < endOffset; { | ||
| chunkData, err := c.getChunkData(int64(i) + startOffset) | ||
| if err != nil { | ||
| return nil, err | ||
| } | ||
| data = append(data, chunkData...) | ||
| i += len(chunkData) | ||
| } | ||
| return data, nil | ||
| } | ||
|
|
||
| func (c *Client) getChunkData(offset int64) ([]byte, error) { | ||
| chunk, err := c.getChunk(offset) | ||
| if err != nil { | ||
| return nil, err | ||
| } | ||
| return base64.RawURLEncoding.DecodeString(chunk.Chunk) | ||
| } | ||
|
|
||
| func (c *Client) getChunk(offset int64) (*TransactionChunk, error) { | ||
| _path := "chunk/" + strconv.FormatInt(offset, 10) | ||
| body, statusCode, err := c.httpGet(_path) | ||
| if statusCode != 200 { | ||
| return nil, errors.New("not found chunk data") | ||
| } | ||
| if err != nil { | ||
| return nil, err | ||
| } | ||
| txChunk := &TransactionChunk{} | ||
| if err := json.Unmarshal(body, txChunk); err != nil { | ||
| return nil, err | ||
| } | ||
| return txChunk, nil | ||
| } |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters