path: root/swarm/api/client/client.go

// Copyright 2016 The go-ethereum Authors
// This file is part of go-ethereum.
//
// go-ethereum is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// go-ethereum is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with go-ethereum. If not, see <http://www.gnu.org/licenses/>.

package client

import (
    "bytes"
    "encoding/json"
    "fmt"
    "io"
    "io/ioutil"
    "mime"
    "net/http"
    "os"
    "path/filepath"
    "strings"

    "github.com/ethereum/go-ethereum/log"
)

var (
    DefaultGateway = "http://localhost:8500"
    DefaultClient  = NewClient(DefaultGateway)
)

// Manifest represents a swarm manifest.
type Manifest struct {
    Entries []ManifestEntry `json:"entries,omitempty"`
}

// ManifestEntry represents an entry in a swarm manifest.
type ManifestEntry struct {
    Hash        string `json:"hash,omitempty"`
    ContentType string `json:"contentType,omitempty"`
    Path        string `json:"path,omitempty"`
}

func NewClient(gateway string) *Client {
    return &Client{
        Gateway: gateway,
    }
}

// Client wraps interaction with a swarm HTTP gateway.
type Client struct {
    Gateway string
}

func (c *Client) UploadDirectory(dir string, defaultPath string) (string, error) {
    mhash, err := c.postRaw("application/json", 2, ioutil.NopCloser(bytes.NewReader([]byte("{}"))))
    if err != nil {
        return "", fmt.Errorf("failed to upload empty manifest")
    }
    if len(defaultPath) > 0 {
        fi, err := os.Stat(defaultPath)
        if err != nil {
            return "", err
        }
        mhash, err = c.uploadToManifest(mhash, "", defaultPath, fi)
        if err != nil {
            return "", err
        }
    }
    prefix := filepath.ToSlash(filepath.Clean(dir)) + "/"
    err = filepath.Walk(dir, func(path string, fi os.FileInfo, err error) error {
        if err != nil || fi.IsDir() {
            return err
        }
        if !strings.HasPrefix(path, dir) {
            return fmt.Errorf("path %s outside directory %s", path, dir)
        }
        uripath := strings.TrimPrefix(filepath.ToSlash(filepath.Clean(path)), prefix)
        mhash, err = c.uploadToManifest(mhash, uripath, path, fi)
        return err
    })
    return mhash, err
}

func (c *Client) UploadFile(file string, fi os.FileInfo, mimetype_hint string) (ManifestEntry, error) {
    var mimetype string
    hash, err := c.uploadFileContent(file, fi)
    if mimetype_hint != "" {
        mimetype = mimetype_hint
        log.Info("Mime type set by override", "mime", mimetype)
    } else {
        ext := filepath.Ext(file)
        log.Info("Ext", "ext", ext, "file", file)
        if ext != "" {
            mimetype = mime.TypeByExtension(filepath.Ext(fi.Name()))
            log.Info("Mime type set by fileextension", "mime", mimetype, "ext", filepath.Ext(file))
        } else {
            f, err := os.Open(file)
            if err == nil {
                first512 := make([]byte, 512)
                fread, _ := f.ReadAt(first512, 0)
                if fread > 0 {
                    mimetype = http.DetectContentType(first512[:fread])
                    log.Info("Mime type set by autodetection", "mime", mimetype)
                }
            }
            f.Close()
        }

    }
    m := ManifestEntry{
        Hash:        hash,
        ContentType: mime.TypeByExtension(filepath.Ext(fi.Name())),
    }
    return m, err
}

func (c *Client) uploadFileContent(file string, fi os.FileInfo) (string, error) {
    fd, err := os.Open(file)
    if err != nil {
        return "", err
    }
    defer fd.Close()
    log.Info("Uploading swarm content", "file", file, "bytes", fi.Size())
    return c.postRaw("application/octet-stream", fi.Size(), fd)
}

func (c *Client) UploadManifest(m Manifest) (string, error) {
    jsm, err := json.Marshal(m)
    if err != nil {
        panic(err)
    }
    log.Info("Uploading swarm manifest")
    return c.postRaw("application/json", int64(len(jsm)), ioutil.NopCloser(bytes.NewReader(jsm)))
}

func (c *Client) uploadToManifest(mhash string, path string, fpath string, fi os.FileInfo) (string, error) {
    fd, err := os.Open(fpath)
    if err != nil {
        return "", err
    }
    defer fd.Close()
    log.Info("Uploading swarm content and path", "file", fpath, "bytes", fi.Size(), "path", path)
    req, err := http.NewRequest("PUT", c.Gateway+"/bzz:/"+mhash+"/"+path, fd)
    if err != nil {
        return "", err
    }
    req.Header.Set("content-type", mime.TypeByExtension(filepath.Ext(fi.Name())))
    req.ContentLength = fi.Size()
    resp, err := http.DefaultClient.Do(req)
    if err != nil {
        return "", err
    }
    defer resp.Body.Close()
    if resp.StatusCode >= 400 {
        return "", fmt.Errorf("bad status: %s", resp.Status)
    }
    content, err := ioutil.ReadAll(resp.Body)
    return string(content), err
}

func (c *Client) postRaw(mimetype string, size int64, body io.ReadCloser) (string, error) {
    req, err := http.NewRequest("POST", c.Gateway+"/bzzr:/", body)
    if err != nil {
        return "", err
    }
    req.Header.Set("content-type", mimetype)
    req.ContentLength = size
    resp, err := http.DefaultClient.Do(req)
    if err != nil {
        return "", err
    }
    defer resp.Body.Close()
    if resp.StatusCode >= 400 {
        return "", fmt.Errorf("bad status: %s", resp.Status)
    }
    content, err := ioutil.ReadAll(resp.Body)
    return string(content), err
}

func (c *Client) DownloadManifest(mhash string) (Manifest, error) {

    mroot := Manifest{}
    req, err := http.NewRequest("GET", c.Gateway+"/bzzr:/"+mhash, nil)
    if err != nil {
        return mroot, err
    }
    resp, err := http.DefaultClient.Do(req)
    if err != nil {
        return mroot, err
    }
    defer resp.Body.Close()

    if resp.StatusCode >= 400 {
        return mroot, fmt.Errorf("bad status: %s", resp.Status)

    }
    content, err := ioutil.ReadAll(resp.Body)

    err = json.Unmarshal(content, &mroot)
    if err != nil {
        return mroot, fmt.Errorf("Manifest %v is malformed: %v", mhash, err)
    }
    return mroot, err
}

// ManifestFileList downloads the manifest with the given hash and generates a
// list of files and directory prefixes which have the specified prefix.
//
// For example, if the manifest represents the following directory structure:
//
// file1.txt
// file2.txt
// dir1/file3.txt
// dir1/dir2/file4.txt
//
// Then:
//
// - a prefix of ""      would return [dir1/, file1.txt, file2.txt]
// - a prefix of "file"  would return [file1.txt, file2.txt]
// - a prefix of "dir1/" would return [dir1/dir2/, dir1/file3.txt]
func (c *Client) ManifestFileList(hash, prefix string) (entries []ManifestEntry, err error) {
    manifest, err := c.DownloadManifest(hash)
    if err != nil {
        return nil, err
    }

    // handleFile handles a manifest entry which is a direct reference to a
    // file (i.e. it is not a swarm manifest)
    handleFile := func(entry ManifestEntry) {
        // ignore the file if it doesn't have the specified prefix
        if !strings.HasPrefix(entry.Path, prefix) {
            return
        }
        // if the path after the prefix contains a directory separator,
        // add a directory prefix to the entries, otherwise add the
        // file
        suffix := strings.TrimPrefix(entry.Path, prefix)
        if sepIndex := strings.Index(suffix, "/"); sepIndex > -1 {
            entries = append(entries, ManifestEntry{
                Path:        prefix + suffix[:sepIndex+1],
                ContentType: "DIR",
            })
        } else {
            if entry.Path == "" {
                entry.Path = "/"
            }
            entries = append(entries, entry)
        }
    }

    // handleManifest handles a manifest entry which is a reference to
    // another swarm manifest.
    handleManifest := func(entry ManifestEntry) error {
        // if the manifest's path is a prefix of the specified prefix
        // then just recurse into the manifest by stripping its path
        // from the prefix
        if strings.HasPrefix(prefix, entry.Path) {
            subPrefix := strings.TrimPrefix(prefix, entry.Path)
            subEntries, err := c.ManifestFileList(entry.Hash, subPrefix)
            if err != nil {
                return err
            }
            // prefix the manifest's path to the sub entries and
            // add them to the returned entries
            for i, subEntry := range subEntries {
                subEntry.Path = entry.Path + subEntry.Path
                subEntries[i] = subEntry
            }
            entries = append(entries, subEntries...)
            return nil
        }

        // if the manifest's path has the specified prefix, then if the
        // path after the prefix contains a directory separator, add a
        // directory prefix to the entries, otherwise recurse into the
        // manifest
        if strings.HasPrefix(entry.Path, prefix) {
            suffix := strings.TrimPrefix(entry.Path, prefix)
            sepIndex := strings.Index(suffix, "/")
            if sepIndex > -1 {
                entries = append(entries, ManifestEntry{
                    Path:        prefix + suffix[:sepIndex+1],
                    ContentType: "DIR",
                })
                return nil
            }
            subEntries, err := c.ManifestFileList(entry.Hash, "")
            if err != nil {
                return err
            }
            // prefix the manifest's path to the sub entries and
            // add them to the returned entries
            for i, subEntry := range subEntries {
                subEntry.Path = entry.Path + subEntry.Path
                subEntries[i] = subEntry
            }
            entries = append(entries, subEntries...)
            return nil
        }
        return nil
    }

    for _, entry := range manifest.Entries {
        if entry.ContentType == "application/bzz-manifest+json" {
            if err := handleManifest(entry); err != nil {
                return nil, err
            }
        } else {
            handleFile(entry)
        }
    }

    return
}