1 files changed, 403 insertions, 0 deletions
diff --git a/tools/convertdb/couch.go b/tools/convertdb/couch.go
new file mode 100644
index 000000000000..764eb49a6099
--- /dev/null
+++ b/tools/convertdb/couch.go
@@ -0,0 +1,403 @@
+// -*- tab-width: 4 -*-
+package couch
+
+import (
+	"bytes"
+	"fmt"
+	"os"
+	"json"
+	"http"
+	"net"
+	"io/ioutil"
+	"url"
+)
+
+var def_hdrs = map[string][]string{}
+
+type buffer struct {
+	b *bytes.Buffer
+}
+
+func (b *buffer) Read(out []byte) (int, os.Error) {
+	return b.b.Read(out)
+}
+
+func (b *buffer) Close() os.Error { return nil }
+
+// Converts given URL to string containing the body of the response.
+func url_to_buf(u string) []byte {
+	if r, err := http.Get(u); err == nil {
+		b, err := ioutil.ReadAll(r.Body)
+		r.Body.Close()
+		if err == nil {
+			return b
+		}
+	}
+	return make([]byte, 0)
+}
+
+type IdAndRev struct {
+	Id  string `json:"_id"`
+	Rev string `json:"_rev"`
+}
+
+// Sends a query to CouchDB and parses the response back.
+// method: the name of the HTTP method (POST, PUT,...)
+// url: the URL to interact with
+// headers: additional headers to pass to the request
+// in: body of the request
+// out: a structure to fill in with the returned JSON document
+func (p Database) interact(method, u string, headers map[string][]string, in []byte, out interface{}) (int, os.Error) {
+	fullHeaders := map[string][]string{}
+	for k, v := range headers {
+		fullHeaders[k] = v
+	}
+	bodyLength := 0
+	if in != nil {
+		bodyLength = len(in)
+		fullHeaders["Content-Type"] = []string{"application/json"}
+	}
+	req := http.Request{
+		Method:        method,
+		ProtoMajor:    1,
+		ProtoMinor:    1,
+		Close:         true,
+		ContentLength: int64(bodyLength),
+		Header:        fullHeaders,
+	}
+	req.TransferEncoding = []string{"chunked"}
+	req.URL, _ = url.Parse(u)
+	if in != nil {
+		req.Body = &buffer{bytes.NewBuffer(in)}
+	}
+	conn, err := net.Dial("tcp", fmt.Sprintf("%s:%s", p.Host, p.Port))
+	if err != nil {
+		return 0, err
+	}
+	http_conn := http.NewClientConn(conn, nil)
+	defer http_conn.Close()
+	if err := http_conn.Write(&req); err != nil {
+		return 0, err
+	}
+	r, err := http_conn.Read(&req)
+	if err != nil {
+		return 0, err
+	}
+	if r.StatusCode < 200 || r.StatusCode >= 300 {
+		b := []byte{}
+		r.Body.Read(b)
+		return r.StatusCode, os.NewError("server said: " + r.Status)
+	}
+	decoder := json.NewDecoder(r.Body)
+	if err = decoder.Decode(out); err != nil {
+		return 0, err
+	}
+	r.Body.Close()
+	return r.StatusCode, nil
+}
+
+type Database struct {
+	Host string
+	Port string
+	Name string
+}
+
+func (p Database) BaseURL() string {
+	return fmt.Sprintf("http://%s:%s", p.Host, p.Port)
+}
+
+func (p Database) DBURL() string {
+	return fmt.Sprintf("%s/%s", p.BaseURL(), p.Name)
+}
+
+// Test whether CouchDB is running (ignores Database.Name)
+func (p Database) Running() bool {
+	u := fmt.Sprintf("%s/%s", p.BaseURL(), "_all_dbs")
+	s := url_to_buf(u)
+	if len(s) > 0 {
+		return true
+	}
+	return false
+}
+
+type database_info struct {
+	Db_name string
+	// other stuff too, ignore for now
+}
+
+// Test whether specified database exists in specified CouchDB instance
+func (p Database) Exists() bool {
+	di := new(database_info)
+	if err := json.Unmarshal(url_to_buf(p.DBURL()), di); err != nil {
+		return false
+	}
+	if di.Db_name != p.Name {
+		return false
+	}
+	return true
+}
+
+func (p Database) create_database() os.Error {
+	ir := response{}
+	if _, err := p.interact("PUT", p.DBURL(), def_hdrs, nil, &ir); err != nil {
+		return err
+	}
+	if !ir.Ok {
+		return os.NewError("Create database operation returned not-OK")
+	}
+	return nil
+}
+
+// Deletes the given database and all documents
+func (p Database) DeleteDatabase() os.Error {
+	ir := response{}
+	if _, err := p.interact("DELETE", p.DBURL(), def_hdrs, nil, &ir); err != nil {
+		return err
+	}
+	if !ir.Ok {
+		return os.NewError("Delete database operation returned not-OK")
+	}
+	return nil
+}
+
+func NewDatabase(host, port, name string) (Database, os.Error) {
+	db := Database{host, port, name}
+	if !db.Running() {
+		return db, os.NewError("CouchDB not running")
+	}
+	if !db.Exists() {
+		if err := db.create_database(); err != nil {
+			return db, err
+		}
+	}
+	return db, nil
+}
+
+// Strip _id and _rev from d, returning them separately if they exist
+func clean_JSON(d interface{}) (json_buf []byte, id, rev string, err os.Error) {
+	json_buf, err = json.Marshal(d)
+	if err != nil {
+		return
+	}
+	m := map[string]interface{}{}
+	err = json.Unmarshal(json_buf, &m)
+	if err != nil {
+		return
+	}
+	id_rev := new(IdAndRev)
+	err = json.Unmarshal(json_buf, &id_rev)
+	if err != nil {
+		return
+	}
+	if _, ok := m["_id"]; ok {
+		id = id_rev.Id
+		m["_id"] = nil, false
+	}
+	if _, ok := m["_rev"]; ok {
+		rev = id_rev.Rev
+		m["_rev"] = nil, false
+	}
+	json_buf, err = json.Marshal(m)
+	return
+}
+
+type response struct {
+	Ok     bool
+	Id     string
+	Rev    string
+	Error  string
+	Reason string
+}
+
+// Inserts document to CouchDB, returning id and rev on success.
+// Document may specify both "_id" and "_rev" fields (will overwrite existing)
+//	or just "_id" (will use that id, but not overwrite existing)
+//	or neither (will use autogenerated id)
+func (p Database) Insert(d interface{}) (string, string, os.Error) {
+	json_buf, id, rev, err := clean_JSON(d)
+	if err != nil {
+		return "", "", err
+	}
+	if id != "" && rev != "" {
+		new_rev, err2 := p.Edit(d)
+		return id, new_rev, err2
+	} else if id != "" {
+		return p.insert_with(json_buf, id)
+	} else if id == "" {
+		return p.insert(json_buf)
+	}
+	return "", "", os.NewError("invalid Document")
+}
+
+// Private implementation of simple autogenerated-id insert
+func (p Database) insert(json_buf []byte) (string, string, os.Error) {
+	ir := response{}
+	if _, err := p.interact("POST", p.DBURL(), def_hdrs, json_buf, &ir); err != nil {
+		return "", "", err
+	}
+	if !ir.Ok {
+		return "", "", os.NewError(fmt.Sprintf("%s: %s", ir.Error, ir.Reason))
+	}
+	return ir.Id, ir.Rev, nil
+}
+
+// Inserts the given document (shouldn't contain "_id" or "_rev" tagged fields)
+// using the passed 'id' as the _id. Will fail if the id already exists.
+func (p Database) InsertWith(d interface{}, id string) (string, string, os.Error) {
+	json_buf, err := json.Marshal(d)
+	if err != nil {
+		return "", "", err
+	}
+	return p.insert_with(json_buf, id)
+}
+
+// Private implementation of insert with given id
+func (p Database) insert_with(json_buf []byte, id string) (string, string, os.Error) {
+	u := fmt.Sprintf("%s/%s", p.DBURL(), url.QueryEscape(id))
+	ir := response{}
+	if _, err := p.interact("PUT", u, def_hdrs, json_buf, &ir); err != nil {
+		return "", "", err
+	}
+	if !ir.Ok {
+		return "", "", os.NewError(fmt.Sprintf("%s: %s", ir.Error, ir.Reason))
+	}
+	return ir.Id, ir.Rev, nil
+}
+
+// Edits the given document, returning the new revision.
+// d must contain "_id" and "_rev" tagged fields.
+func (p Database) Edit(d interface{}) (string, os.Error) {
+	json_buf, err := json.Marshal(d)
+	if err != nil {
+		return "", err
+	}
+	id_rev := new(IdAndRev)
+	err = json.Unmarshal(json_buf, id_rev)
+	if err != nil {
+		return "", err
+	}
+	if id_rev.Id == "" {
+		return "", os.NewError("Id not specified in interface")
+	}
+	if id_rev.Rev == "" {
+		return "", os.NewError("Rev not specified in interface (try InsertWith)")
+	}
+	u := fmt.Sprintf("%s/%s", p.DBURL(), url.QueryEscape(id_rev.Id))
+	ir := response{}
+	if _, err = p.interact("PUT", u, def_hdrs, json_buf, &ir); err != nil {
+		return "", err
+	}
+	return ir.Rev, nil
+}
+
+// Edits the given document, returning the new revision.
+// d should not contain "_id" or "_rev" tagged fields. If it does, they will
+// be overwritten with the passed values.
+func (p Database) EditWith(d interface{}, id, rev string) (string, os.Error) {
+	if id == "" || rev == "" {
+		return "", os.NewError("EditWith: must specify both id and rev")
+	}
+	json_buf, err := json.Marshal(d)
+	if err != nil {
+		return "", err
+	}
+	m := map[string]interface{}{}
+	err = json.Unmarshal(json_buf, &m)
+	if err != nil {
+		return "", err
+	}
+	m["_id"] = id
+	m["_rev"] = rev
+	return p.Edit(m)
+}
+
+// Unmarshals the document matching id to the given interface, returning rev.
+func (p Database) Retrieve(id string, d interface{}) (string, os.Error) {
+	if id == "" {
+		return "", os.NewError("no id specified")
+	}
+	json_buf := url_to_buf(fmt.Sprintf("%s/%s", p.DBURL(), id))
+	id_rev := new(IdAndRev)
+	if err := json.Unmarshal(json_buf, &id_rev); err != nil {
+		return "", err
+	}
+	if id_rev.Id != id {
+		return "", os.NewError("invalid id specified")
+	}
+	return id_rev.Rev, json.Unmarshal(json_buf, d)
+}
+
+// Deletes document given by id and rev.
+func (p Database) Delete(id, rev string) os.Error {
+	headers := map[string][]string{
+		"If-Match": []string{rev},
+	}
+	u := fmt.Sprintf("%s/%s", p.DBURL(), id)
+	ir := response{}
+	if _, err := p.interact("DELETE", u, headers, nil, &ir); err != nil {
+		return err
+	}
+	if !ir.Ok {
+		return os.NewError(fmt.Sprintf("%s: %s", ir.Error, ir.Reason))
+	}
+	return nil
+}
+
+type Row struct {
+	Id  *string
+}
+
+type keyed_view_response struct {
+	Total_rows uint64
+	Offset     uint64
+	Rows       []Row
+}
+
+// Return array of document ids as returned by the given view/options combo.
+// view should be eg. "_design/my_foo/_view/my_bar"
+// options should be eg. { "limit": 10, "key": "baz" }
+func (p Database) QueryIds(view string, options map[string]interface{}) ([]string, os.Error) {
+	kvr := new(keyed_view_response)
+
+	if err := p.Query(view, options, kvr); err != nil {
+		fmt.Println("Query error: " + err.String())
+		return make([]string, 0), err
+	}
+	ids := make([]string, len(kvr.Rows))
+	i := 0
+	for _, row := range kvr.Rows {
+		if row.Id != nil {
+			ids[i] = *row.Id
+			i++
+		}
+	}
+	return ids[:i], nil
+}
+
+func (p Database) Query(view string, options map[string]interface{}, results interface{}) os.Error {
+	if view == "" {
+		return os.NewError("empty view")
+	}
+
+	var parameters string
+	for k, v := range options {
+		switch t := v.(type) {
+		case string:
+			parameters += fmt.Sprintf(`%s=%s&`, k, url.QueryEscape(t))
+		case int:
+			parameters += fmt.Sprintf(`%s=%d&`, k, t)
+		case bool:
+			parameters += fmt.Sprintf(`%s=%v&`, k, t)
+		default:
+			// TODO more types are supported
+			panic(fmt.Sprintf("unsupported value-type %T in Query", t))
+		}
+	}
+	full_url := fmt.Sprintf("%s/%s?%s", p.DBURL(), view, parameters)
+	json_buf := url_to_buf(full_url)
+
+	if err := json.Unmarshal(json_buf, results); err != nil {
+		return err
+	}
+	return nil
+}