diff options
Diffstat (limited to 'vendor/github.com/goamz/goamz/exp/sdb/sdb.go')
| -rw-r--r-- | vendor/github.com/goamz/goamz/exp/sdb/sdb.go | 413 |
1 files changed, 413 insertions, 0 deletions
diff --git a/vendor/github.com/goamz/goamz/exp/sdb/sdb.go b/vendor/github.com/goamz/goamz/exp/sdb/sdb.go new file mode 100644 index 000000000..0d13f4a9e --- /dev/null +++ b/vendor/github.com/goamz/goamz/exp/sdb/sdb.go @@ -0,0 +1,413 @@ +// +// goamz - Go packages to interact with the Amazon Web Services. +// +// https://wiki.ubuntu.com/goamz +// +// Copyright (c) 2011 AppsAttic Ltd. +// +// sdb package written by: +// +// Andrew Chilton <chilts@appsattic.com> +// Brad Rydzewski <brad.rydzewski@gmail.com> + +// This package is in an experimental state, and does not currently +// follow conventions and style of the rest of goamz or common +// Go conventions. It must be polished before it's considered a +// first-class package in goamz. +package sdb + +// BUG: SelectResp isn't properly organized. It must change. + +// + +import ( + "encoding/xml" + "github.com/goamz/goamz/aws" + "log" + "net/http" + "net/http/httputil" + "net/url" + "strconv" + "time" +) + +const debug = false + +// The SDB type encapsulates operations with a specific SimpleDB region. +type SDB struct { + aws.Auth + aws.Region + private byte // Reserve the right of using private data. +} + +// New creates a new SDB. +func New(auth aws.Auth, region aws.Region) *SDB { + return &SDB{auth, region, 0} +} + +// The Domain type represents a collection of items that are described +// by name-value attributes. +type Domain struct { + *SDB + Name string +} + +// Domain returns a Domain with the given name. +func (sdb *SDB) Domain(name string) *Domain { + return &Domain{sdb, name} +} + +// The Item type represent individual objects that contain one or more +// name-value attributes stored within a SDB Domain as rows. +type Item struct { + *SDB + *Domain + Name string +} + +// Item returns an Item with the given name. +func (domain *Domain) Item(name string) *Item { + return &Item{domain.SDB, domain, name} +} + +// The Attr type represent categories of data that can be assigned to items. +type Attr struct { + Name string + Value string +} + +// ---------------------------------------------------------------------------- +// Service-level operations. + +// --- ListDomains + +// Response to a ListDomains request. +// +// See http://goo.gl/3u0Cf for more details. +type ListDomainsResp struct { + Domains []string `xml:"ListDomainsResult>DomainName"` + NextToken string `xml:"ListDomainsResult>NextToken"` + ResponseMetadata ResponseMetadata +} + +// ListDomains lists all domains in sdb. +// +// See http://goo.gl/Dsw15 for more details. +func (sdb *SDB) ListDomains() (resp *ListDomainsResp, err error) { + return sdb.ListDomainsN(0, "") +} + +// ListDomainsN lists domains in sdb up to maxDomains. +// If nextToken is not empty, domains listed will start at the given token. +// +// See http://goo.gl/Dsw15 for more details. +func (sdb *SDB) ListDomainsN(maxDomains int, nextToken string) (resp *ListDomainsResp, err error) { + params := makeParams("ListDomains") + if maxDomains != 0 { + params["MaxNumberOfDomains"] = []string{strconv.Itoa(maxDomains)} + } + if nextToken != "" { + params["NextToken"] = []string{nextToken} + } + resp = &ListDomainsResp{} + err = sdb.query(nil, nil, params, nil, resp) + return +} + +// --- SelectExpression + +// Response to a Select request. +// +// See http://goo.gl/GTsSZ for more details. +type SelectResp struct { + Items []struct { + Name string + Attrs []Attr `xml:"Attribute"` + } `xml:"SelectResult>Item"` + ResponseMetadata ResponseMetadata +} + +// Select returns a set of items and attributes that match expr. +// Select is similar to the standard SQL SELECT statement. +// +// See http://goo.gl/GTsSZ for more details. +func (sdb *SDB) Select(expr string, consistent bool) (resp *SelectResp, err error) { + resp = &SelectResp{} + params := makeParams("Select") + params["SelectExpression"] = []string{expr} + if consistent { + params["ConsistentRead"] = []string{"true"} + } + err = sdb.query(nil, nil, params, nil, resp) + return +} + +// ---------------------------------------------------------------------------- +// Domain-level operations. + +// --- CreateDomain + +// CreateDomain creates a new domain. +// +// See http://goo.gl/jDjGH for more details. +func (domain *Domain) CreateDomain() (resp *SimpleResp, err error) { + params := makeParams("CreateDomain") + resp = &SimpleResp{} + err = domain.SDB.query(domain, nil, params, nil, resp) + return +} + +// DeleteDomain deletes an existing domain. +// +// See http://goo.gl/S0dCL for more details. +func (domain *Domain) DeleteDomain() (resp *SimpleResp, err error) { + params := makeParams("DeleteDomain") + resp = &SimpleResp{} + err = domain.SDB.query(domain, nil, params, nil, resp) + return +} + +// ---------------------------------------------------------------------------- +// Item-level operations. + +type PutAttrs struct { + attrs []Attr + expected []Attr + replace map[string]bool + missing map[string]bool +} + +func (pa *PutAttrs) Add(name, value string) { + pa.attrs = append(pa.attrs, Attr{name, value}) +} + +func (pa *PutAttrs) Replace(name, value string) { + pa.Add(name, value) + if pa.replace == nil { + pa.replace = make(map[string]bool) + } + pa.replace[name] = true +} + +// The PutAttrs request will only succeed if the existing +// item in SimpleDB contains a matching name / value pair. +func (pa *PutAttrs) IfValue(name, value string) { + pa.expected = append(pa.expected, Attr{name, value}) +} + +// Flag to test the existence of an attribute while performing +// conditional updates. X can be any positive integer or 0. +// +// This should set Expected.N.Name=name and Expected.N.Exists=false +func (pa *PutAttrs) IfMissing(name string) { + if pa.missing == nil { + pa.missing = make(map[string]bool) + } + pa.missing[name] = true +} + +// PutAttrs adds attrs to item. +// +// See http://goo.gl/yTAV4 for more details. +func (item *Item) PutAttrs(attrs *PutAttrs) (resp *SimpleResp, err error) { + params := makeParams("PutAttributes") + resp = &SimpleResp{} + + // copy these attrs over to the parameters + itemNum := 1 + for _, attr := range attrs.attrs { + itemNumStr := strconv.Itoa(itemNum) + + // do the name, value and replace + params["Attribute."+itemNumStr+".Name"] = []string{attr.Name} + params["Attribute."+itemNumStr+".Value"] = []string{attr.Value} + + if _, ok := attrs.replace[attr.Name]; ok { + params["Attribute."+itemNumStr+".Replace"] = []string{"true"} + } + + itemNum++ + } + + //append expected values to params + expectedNum := 1 + for _, attr := range attrs.expected { + expectedNumStr := strconv.Itoa(expectedNum) + params["Expected."+expectedNumStr+".Name"] = []string{attr.Name} + params["Expected."+expectedNumStr+".Value"] = []string{attr.Value} + + if attrs.missing[attr.Name] { + params["Expected."+expectedNumStr+".Exists"] = []string{"false"} + } + expectedNum++ + } + + err = item.query(params, nil, resp) + if err != nil { + return nil, err + } + return +} + +// Response to an Attrs request. +// +// See http://goo.gl/45X1M for more details. +type AttrsResp struct { + Attrs []Attr `xml:"GetAttributesResult>Attribute"` + ResponseMetadata ResponseMetadata +} + +// Attrs returns one or more of the named attributes, or +// all of item's attributes if names is nil. +// If consistent is true, previous writes will necessarily +// be observed. +// +// See http://goo.gl/45X1M for more details. +func (item *Item) Attrs(names []string, consistent bool) (resp *AttrsResp, err error) { + params := makeParams("GetAttributes") + params["ItemName"] = []string{item.Name} + if consistent { + params["ConsistentRead"] = []string{"true"} + } + + // Copy these attributes over to the parameters + for i, name := range names { + params["AttributeName."+strconv.Itoa(i+1)] = []string{name} + } + + resp = &AttrsResp{} + err = item.query(params, nil, resp) + if err != nil { + return nil, err + } + return +} + +// ---------------------------------------------------------------------------- +// Generic data structures for all requests/responses. + +// Error encapsulates an error returned by SDB. +type Error struct { + StatusCode int // HTTP status code (200, 403, ...) + StatusMsg string // HTTP status message ("Service Unavailable", "Bad Request", ...) + Code string // SimpleDB error code ("InvalidParameterValue", ...) + Message string // The human-oriented error message + RequestId string // A unique ID for this request + BoxUsage float64 // The measure of machine utilization for this request. +} + +func (err *Error) Error() string { + return err.Message +} + +// SimpleResp represents a response to an SDB request which on success +// will return no other information besides ResponseMetadata. +type SimpleResp struct { + ResponseMetadata ResponseMetadata +} + +// ResponseMetadata +type ResponseMetadata struct { + RequestId string // A unique ID for tracking the request + BoxUsage float64 // The measure of machine utilization for this request. +} + +func buildError(r *http.Response) error { + err := Error{} + err.StatusCode = r.StatusCode + err.StatusMsg = r.Status + xml.NewDecoder(r.Body).Decode(&err) + return &err +} + +// ---------------------------------------------------------------------------- +// Request dispatching logic. + +func (item *Item) query(params url.Values, headers http.Header, resp interface{}) error { + return item.Domain.SDB.query(item.Domain, item, params, headers, resp) +} + +func (domain *Domain) query(item *Item, params url.Values, headers http.Header, resp interface{}) error { + return domain.SDB.query(domain, item, params, headers, resp) +} + +func (sdb *SDB) query(domain *Domain, item *Item, params url.Values, headers http.Header, resp interface{}) error { + // all SimpleDB operations have path="/" + method := "GET" + path := "/" + + // if we have been given no headers or params, create them + if headers == nil { + headers = map[string][]string{} + } + if params == nil { + params = map[string][]string{} + } + + // setup some default parameters + params["Version"] = []string{"2009-04-15"} + params["Timestamp"] = []string{time.Now().UTC().Format(time.RFC3339)} + + // set the DomainName param (every request must have one) + if domain != nil { + params["DomainName"] = []string{domain.Name} + } + + // set the ItemName if we have one + if item != nil { + params["ItemName"] = []string{item.Name} + } + + // check the endpoint URL + u, err := url.Parse(sdb.Region.SDBEndpoint) + if err != nil { + return err + } + headers["Host"] = []string{u.Host} + sign(sdb.Auth, method, path, params, headers) + + u.Path = path + if len(params) > 0 { + u.RawQuery = params.Encode() + } + req := http.Request{ + URL: u, + Method: method, + ProtoMajor: 1, + ProtoMinor: 1, + Close: true, + Header: headers, + } + + if v, ok := headers["Content-Length"]; ok { + req.ContentLength, _ = strconv.ParseInt(v[0], 10, 64) + delete(headers, "Content-Length") + } + + r, err := http.DefaultClient.Do(&req) + if err != nil { + return err + } + defer r.Body.Close() + + if debug { + dump, _ := httputil.DumpResponse(r, true) + log.Printf("response:\n") + log.Printf("%v\n}\n", string(dump)) + } + + // status code is always 200 when successful (since we're always doing a GET) + if r.StatusCode != 200 { + return buildError(r) + } + + // everything was fine, so unmarshal the XML and return what it's err is (if any) + err = xml.NewDecoder(r.Body).Decode(resp) + return err +} + +func makeParams(action string) map[string][]string { + params := make(map[string][]string) + params["Action"] = []string{action} + return params +} |