/
state.go
1608 lines (1506 loc) · 48.1 KB
/
state.go
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// Copyright 2012, 2013 Canonical Ltd.
// Licensed under the AGPLv3, see LICENCE file for details.
// Package state enables reading, observing, and changing
// the state stored in MongoDB of a whole environment
// managed by juju.
package state
import (
"fmt"
"net"
"net/url"
"regexp"
"sort"
"strconv"
"strings"
"sync"
"github.com/juju/errors"
"github.com/juju/loggo"
"labix.org/v2/mgo"
"labix.org/v2/mgo/bson"
"labix.org/v2/mgo/txn"
"github.com/juju/core/charm"
"github.com/juju/core/constraints"
"github.com/juju/core/environs/config"
"github.com/juju/core/names"
"github.com/juju/core/state/api/params"
"github.com/juju/core/state/multiwatcher"
"github.com/juju/core/state/presence"
"github.com/juju/core/state/watcher"
"github.com/juju/core/utils"
"github.com/juju/core/version"
)
var logger = loggo.GetLogger("juju.state")
// BootstrapNonce is used as a nonce for the state server machine.
const (
BootstrapNonce = "user-admin:bootstrap"
AdminUser = "admin"
)
// State represents the state of an environment
// managed by juju.
type State struct {
info *Info
policy Policy
db *mgo.Database
environments *mgo.Collection
charms *mgo.Collection
machines *mgo.Collection
instanceData *mgo.Collection
containerRefs *mgo.Collection
relations *mgo.Collection
relationScopes *mgo.Collection
services *mgo.Collection
requestedNetworks *mgo.Collection
networks *mgo.Collection
networkInterfaces *mgo.Collection
minUnits *mgo.Collection
settings *mgo.Collection
settingsrefs *mgo.Collection
constraints *mgo.Collection
units *mgo.Collection
actions *mgo.Collection
users *mgo.Collection
presence *mgo.Collection
cleanups *mgo.Collection
annotations *mgo.Collection
statuses *mgo.Collection
stateServers *mgo.Collection
runner *txn.Runner
transactionHooks chan ([]transactionHook)
watcher *watcher.Watcher
pwatcher *presence.Watcher
// mu guards allManager.
mu sync.Mutex
allManager *multiwatcher.StoreManager
}
// transactionHook holds a pair of functions to be called before and after a
// mgo/txn transaction is run. It is only used in testing.
type transactionHook struct {
Before func()
After func()
}
// runTransaction runs the supplied operations as a single mgo/txn transaction,
// and includes a mechanism whereby tests can use SetTransactionHooks to induce
// arbitrary state mutations before and after particular transactions.
func (st *State) runTransaction(ops []txn.Op) error {
transactionHooks := <-st.transactionHooks
st.transactionHooks <- nil
if len(transactionHooks) > 0 {
// Note that this code should only ever be triggered
// during tests. If we see the log messages below
// in a production run, something is wrong.
defer func() {
if transactionHooks[0].After != nil {
logger.Infof("transaction 'after' hook start")
transactionHooks[0].After()
logger.Infof("transaction 'after' hook end")
}
if <-st.transactionHooks != nil {
panic("concurrent use of transaction hooks")
}
st.transactionHooks <- transactionHooks[1:]
}()
if transactionHooks[0].Before != nil {
logger.Infof("transaction 'before' hook start")
transactionHooks[0].Before()
logger.Infof("transaction 'before' hook end")
}
}
return st.runner.Run(ops, "", nil)
}
// Ping probes the state's database connection to ensure
// that it is still alive.
func (st *State) Ping() error {
return st.db.Session.Ping()
}
// MongoSession returns the underlying mongodb session
// used by the state. It is exposed so that external code
// can maintain the mongo replica set and should not
// otherwise be used.
func (st *State) MongoSession() *mgo.Session {
return st.db.Session
}
func (st *State) Watch() *multiwatcher.Watcher {
st.mu.Lock()
if st.allManager == nil {
st.allManager = multiwatcher.NewStoreManager(newAllWatcherStateBacking(st))
}
st.mu.Unlock()
return multiwatcher.NewWatcher(st.allManager)
}
func (st *State) EnvironConfig() (*config.Config, error) {
settings, err := readSettings(st, environGlobalKey)
if err != nil {
return nil, err
}
attrs := settings.Map()
return config.New(config.NoDefaults, attrs)
}
// checkEnvironConfig returns an error if the config is definitely invalid.
func checkEnvironConfig(cfg *config.Config) error {
if cfg.AdminSecret() != "" {
return fmt.Errorf("admin-secret should never be written to the state")
}
if _, ok := cfg.AgentVersion(); !ok {
return fmt.Errorf("agent-version must always be set in state")
}
return nil
}
// versionInconsistentError indicates one or more agents have a
// different version from the current one (even empty, when not yet
// set).
type versionInconsistentError struct {
currentVersion version.Number
agents []string
}
func (e *versionInconsistentError) Error() string {
sort.Strings(e.agents)
return fmt.Sprintf("some agents have not upgraded to the current environment version %s: %s", e.currentVersion, strings.Join(e.agents, ", "))
}
// newVersionInconsistentError returns a new instance of
// versionInconsistentError.
func newVersionInconsistentError(currentVersion version.Number, agents []string) *versionInconsistentError {
return &versionInconsistentError{currentVersion, agents}
}
// IsVersionInconsistentError returns if the given error is
// versionInconsistentError.
func IsVersionInconsistentError(e interface{}) bool {
_, ok := e.(*versionInconsistentError)
return ok
}
func (st *State) checkCanUpgrade(currentVersion, newVersion string) error {
matchCurrent := "^" + regexp.QuoteMeta(currentVersion) + "-"
matchNew := "^" + regexp.QuoteMeta(newVersion) + "-"
// Get all machines and units with a different or empty version.
sel := bson.D{{"$or", []bson.D{
{{"tools", bson.D{{"$exists", false}}}},
{{"$and", []bson.D{
{{"tools.version", bson.D{{"$not", bson.RegEx{matchCurrent, ""}}}}},
{{"tools.version", bson.D{{"$not", bson.RegEx{matchNew, ""}}}}},
}}},
}}}
var agentTags []string
for _, collection := range []*mgo.Collection{st.machines, st.units} {
var doc struct {
Id string `bson:"_id"`
}
iter := collection.Find(sel).Select(bson.D{{"_id", 1}}).Iter()
for iter.Next(&doc) {
switch collection.Name {
case "machines":
agentTags = append(agentTags, names.MachineTag(doc.Id))
case "units":
agentTags = append(agentTags, names.UnitTag(doc.Id))
}
}
if err := iter.Err(); err != nil {
return err
}
}
if len(agentTags) > 0 {
return newVersionInconsistentError(version.MustParse(currentVersion), agentTags)
}
return nil
}
// SetEnvironAgentVersion changes the agent version for the
// environment to the given version, only if the environment is in a
// stable state (all agents are running the current version).
func (st *State) SetEnvironAgentVersion(newVersion version.Number) error {
for i := 0; i < 5; i++ {
settings, err := readSettings(st, environGlobalKey)
if err != nil {
return err
}
agentVersion, ok := settings.Get("agent-version")
if !ok {
return fmt.Errorf("no agent version set in the environment")
}
currentVersion, ok := agentVersion.(string)
if !ok {
return fmt.Errorf("invalid agent version format: expected string, got %v", agentVersion)
}
if newVersion.String() == currentVersion {
// Nothing to do.
return nil
}
if err := st.checkCanUpgrade(currentVersion, newVersion.String()); err != nil {
return err
}
ops := []txn.Op{{
C: st.settings.Name,
Id: environGlobalKey,
Assert: bson.D{{"txn-revno", settings.txnRevno}},
Update: bson.D{{"$set", bson.D{{"agent-version", newVersion.String()}}}},
}}
if err := st.runTransaction(ops); err == nil {
return nil
} else if err != txn.ErrAborted {
return fmt.Errorf("cannot set agent-version: %v", err)
}
}
return ErrExcessiveContention
}
func (st *State) buildAndValidateEnvironConfig(updateAttrs map[string]interface{}, removeAttrs []string, oldConfig *config.Config) (validCfg *config.Config, err error) {
newConfig, err := oldConfig.Apply(updateAttrs)
if err != nil {
return nil, err
}
if len(removeAttrs) != 0 {
newConfig, err = newConfig.Remove(removeAttrs)
if err != nil {
return nil, err
}
}
if err := checkEnvironConfig(newConfig); err != nil {
return nil, err
}
return st.validate(newConfig, oldConfig)
}
type ValidateConfigFunc func(updateAttrs map[string]interface{}, removeAttrs []string, oldConfig *config.Config) error
// UpdateEnvironConfig adds, updates or removes attributes in the current
// configuration of the environment with the provided updateAttrs and
// removeAttrs.
func (st *State) UpdateEnvironConfig(updateAttrs map[string]interface{}, removeAttrs []string, additionalValidation ValidateConfigFunc) error {
if len(updateAttrs)+len(removeAttrs) == 0 {
return nil
}
// TODO(axw) 2013-12-6 #1167616
// Ensure that the settings on disk have not changed
// underneath us. The settings changes are actually
// applied as a delta to what's on disk; if there has
// been a concurrent update, the change may not be what
// the user asked for.
settings, err := readSettings(st, environGlobalKey)
if err != nil {
return err
}
// Get the existing environment config from state.
oldConfig, err := config.New(config.NoDefaults, settings.Map())
if err != nil {
return err
}
if additionalValidation != nil {
err = additionalValidation(updateAttrs, removeAttrs, oldConfig)
if err != nil {
return err
}
}
validCfg, err := st.buildAndValidateEnvironConfig(updateAttrs, removeAttrs, oldConfig)
if err != nil {
return err
}
validAttrs := validCfg.AllAttrs()
for k := range oldConfig.AllAttrs() {
if _, ok := validAttrs[k]; !ok {
settings.Delete(k)
}
}
settings.Update(validAttrs)
_, err = settings.Write()
return err
}
// EnvironConstraints returns the current environment constraints.
func (st *State) EnvironConstraints() (constraints.Value, error) {
return readConstraints(st, environGlobalKey)
}
// SetEnvironConstraints replaces the current environment constraints.
func (st *State) SetEnvironConstraints(cons constraints.Value) error {
unsupported, err := st.validateConstraints(cons)
if len(unsupported) > 0 {
logger.Warningf(
"setting environment constraints: unsupported constraints: %v", strings.Join(unsupported, ","))
} else if err != nil {
return err
}
return writeConstraints(st, environGlobalKey, cons)
}
var errDead = fmt.Errorf("not found or dead")
var errNotAlive = fmt.Errorf("not found or not alive")
func onAbort(txnErr, err error) error {
if txnErr == txn.ErrAborted {
return err
}
return txnErr
}
// AllMachines returns all machines in the environment
// ordered by id.
func (st *State) AllMachines() (machines []*Machine, err error) {
mdocs := machineDocSlice{}
err = st.machines.Find(nil).All(&mdocs)
if err != nil {
return nil, fmt.Errorf("cannot get all machines: %v", err)
}
sort.Sort(mdocs)
for _, doc := range mdocs {
machines = append(machines, newMachine(st, &doc))
}
return
}
type machineDocSlice []machineDoc
func (ms machineDocSlice) Len() int { return len(ms) }
func (ms machineDocSlice) Swap(i, j int) { ms[i], ms[j] = ms[j], ms[i] }
func (ms machineDocSlice) Less(i, j int) bool {
return machineIdLessThan(ms[i].Id, ms[j].Id)
}
// machineIdLessThan returns true if id1 < id2, false otherwise.
// Machine ids may include "/" separators if they are for a container so
// the comparison is done by comparing the id component values from
// left to right (most significant part to least significant). Ids for
// host machines are always less than ids for their containers.
func machineIdLessThan(id1, id2 string) bool {
// Most times, we are dealing with host machines and not containers, so we will
// try interpreting the ids as ints - this will be faster than dealing with the
// container ids below.
mint1, err1 := strconv.Atoi(id1)
mint2, err2 := strconv.Atoi(id2)
if err1 == nil && err2 == nil {
return mint1 < mint2
}
// We have at least one container id so it gets complicated.
idParts1 := strings.Split(id1, "/")
idParts2 := strings.Split(id2, "/")
nrParts1 := len(idParts1)
nrParts2 := len(idParts2)
minLen := nrParts1
if nrParts2 < minLen {
minLen = nrParts2
}
for x := 0; x < minLen; x++ {
m1 := idParts1[x]
m2 := idParts2[x]
if m1 == m2 {
continue
}
// See if the id part is a container type, and if so compare directly.
if x%2 == 1 {
return m1 < m2
}
// Compare the integer ids.
// There's nothing we can do with errors at this point.
mint1, _ := strconv.Atoi(m1)
mint2, _ := strconv.Atoi(m2)
return mint1 < mint2
}
return nrParts1 < nrParts2
}
// Machine returns the machine with the given id.
func (st *State) Machine(id string) (*Machine, error) {
mdoc := &machineDoc{}
sel := bson.D{{"_id", id}}
err := st.machines.Find(sel).One(mdoc)
if err == mgo.ErrNotFound {
return nil, errors.NotFoundf("machine %s", id)
}
if err != nil {
return nil, fmt.Errorf("cannot get machine %s: %v", id, err)
}
return newMachine(st, mdoc), nil
}
// FindEntity returns the entity with the given tag.
//
// The returned value can be of type *Machine, *Unit,
// *User, *Service or *Environment, depending
// on the tag.
func (st *State) FindEntity(tag string) (Entity, error) {
kind, id, err := names.ParseTag(tag, "")
switch kind {
case names.MachineTagKind:
return st.Machine(id)
case names.UnitTagKind:
return st.Unit(id)
case names.UserTagKind:
return st.User(id)
case names.ServiceTagKind:
return st.Service(id)
case names.EnvironTagKind:
env, err := st.Environment()
if err != nil {
return nil, err
}
// Return an invalid entity error if the requested environment is not
// the current one.
if id != env.UUID() {
if utils.IsValidUUIDString(id) {
return nil, errors.NotFoundf("environment %q", id)
}
// TODO(axw) 2013-12-04 #1257587
// We should not accept environment tags that do not match the
// environment's UUID. We accept anything for now, to cater
// both for past usage, and for potentially supporting aliases.
logger.Warningf("environment-tag does not match current environment UUID: %q != %q", id, env.UUID())
conf, err := st.EnvironConfig()
if err != nil {
logger.Warningf("EnvironConfig failed: %v", err)
} else if id != conf.Name() {
logger.Warningf("environment-tag does not match current environment name: %q != %q", id, conf.Name())
}
}
return env, nil
case names.RelationTagKind:
return st.KeyRelation(id)
case names.NetworkTagKind:
return st.Network(id)
}
return nil, err
}
// parseTag, given an entity tag, returns the collection name and id
// of the entity document.
func (st *State) parseTag(tag string) (coll string, id string, err error) {
kind, id, err := names.ParseTag(tag, "")
if err != nil {
return "", "", err
}
switch kind {
case names.MachineTagKind:
coll = st.machines.Name
case names.ServiceTagKind:
coll = st.services.Name
case names.UnitTagKind:
coll = st.units.Name
case names.UserTagKind:
coll = st.users.Name
case names.RelationTagKind:
coll = st.relations.Name
case names.EnvironTagKind:
coll = st.environments.Name
case names.NetworkTagKind:
coll = st.networks.Name
default:
return "", "", fmt.Errorf("%q is not a valid collection tag", tag)
}
return coll, id, nil
}
// AddCharm adds the ch charm with curl to the state. bundleURL must
// be set to a URL where the bundle for ch may be downloaded from. On
// success the newly added charm state is returned.
func (st *State) AddCharm(ch charm.Charm, curl *charm.URL, bundleURL *url.URL, bundleSha256 string) (stch *Charm, err error) {
// The charm may already exist in state as a placeholder, so we
// check for that situation and update the existing charm record
// if necessary, otherwise add a new record.
var existing charmDoc
err = st.charms.Find(bson.D{{"_id", curl.String()}, {"placeholder", true}}).One(&existing)
if err == mgo.ErrNotFound {
cdoc := &charmDoc{
URL: curl,
Meta: ch.Meta(),
Config: ch.Config(),
BundleURL: bundleURL,
BundleSha256: bundleSha256,
}
err = st.charms.Insert(cdoc)
if err != nil {
return nil, fmt.Errorf("cannot add charm %q: %v", curl, err)
}
return newCharm(st, cdoc)
} else if err != nil {
return nil, err
}
return st.updateCharmDoc(ch, curl, bundleURL, bundleSha256, stillPlaceholder)
}
// Charm returns the charm with the given URL. Charms pending upload
// to storage and placeholders are never returned.
func (st *State) Charm(curl *charm.URL) (*Charm, error) {
cdoc := &charmDoc{}
what := bson.D{
{"_id", curl},
{"placeholder", bson.D{{"$ne", true}}},
{"pendingupload", bson.D{{"$ne", true}}},
}
err := st.charms.Find(what).One(&cdoc)
if err == mgo.ErrNotFound {
return nil, errors.NotFoundf("charm %q", curl)
}
if err != nil {
return nil, fmt.Errorf("cannot get charm %q: %v", curl, err)
}
if err := cdoc.Meta.Check(); err != nil {
return nil, fmt.Errorf("malformed charm metadata found in state: %v", err)
}
return newCharm(st, cdoc)
}
// LatestPlaceholderCharm returns the latest charm described by the
// given URL but which is not yet deployed.
func (st *State) LatestPlaceholderCharm(curl *charm.URL) (*Charm, error) {
noRevURL := curl.WithRevision(-1)
curlRegex := "^" + regexp.QuoteMeta(noRevURL.String())
var docs []charmDoc
err := st.charms.Find(bson.D{{"_id", bson.D{{"$regex", curlRegex}}}, {"placeholder", true}}).All(&docs)
if err != nil {
return nil, fmt.Errorf("cannot get charm %q: %v", curl, err)
}
// Find the highest revision.
var latest charmDoc
for _, doc := range docs {
if latest.URL == nil || doc.URL.Revision > latest.URL.Revision {
latest = doc
}
}
if latest.URL == nil {
return nil, errors.NotFoundf("placeholder charm %q", noRevURL)
}
return newCharm(st, &latest)
}
// PrepareLocalCharmUpload must be called before a local charm is
// uploaded to the provider storage in order to create a charm
// document in state. It returns the chosen unique charm URL reserved
// in state for the charm.
//
// The url's schema must be "local" and it must include a revision.
func (st *State) PrepareLocalCharmUpload(curl *charm.URL) (chosenUrl *charm.URL, err error) {
// Perform a few sanity checks first.
if curl.Schema != "local" {
return nil, fmt.Errorf("expected charm URL with local schema, got %q", curl)
}
if curl.Revision < 0 {
return nil, fmt.Errorf("expected charm URL with revision, got %q", curl)
}
// Get a regex with the charm URL and no revision.
noRevURL := curl.WithRevision(-1)
curlRegex := "^" + regexp.QuoteMeta(noRevURL.String())
for attempt := 0; attempt < 3; attempt++ {
// Find the highest revision of that charm in state.
var docs []charmDoc
err = st.charms.Find(bson.D{{"_id", bson.D{{"$regex", curlRegex}}}}).Select(bson.D{{"_id", 1}}).All(&docs)
if err != nil {
return nil, err
}
// Find the highest revision.
maxRevision := -1
for _, doc := range docs {
if doc.URL.Revision > maxRevision {
maxRevision = doc.URL.Revision
}
}
// Respect the local charm's revision first.
chosenRevision := curl.Revision
if maxRevision >= chosenRevision {
// More recent revision exists in state, pick the next.
chosenRevision = maxRevision + 1
}
chosenUrl = curl.WithRevision(chosenRevision)
uploadedCharm := &charmDoc{
URL: chosenUrl,
PendingUpload: true,
}
ops := []txn.Op{{
C: st.charms.Name,
Id: uploadedCharm.URL,
Assert: txn.DocMissing,
Insert: uploadedCharm,
}}
// Run the transaction, and retry on abort.
if err = st.runTransaction(ops); err == txn.ErrAborted {
continue
} else if err != nil {
return nil, err
}
break
}
if err != nil {
return nil, ErrExcessiveContention
}
return chosenUrl, nil
}
// PrepareStoreCharmUpload must be called before a charm store charm
// is uploaded to the provider storage in order to create a charm
// document in state. If a charm with the same URL is already in
// state, it will be returned as a *state.Charm (is can be still
// pending or already uploaded). Otherwise, a new charm document is
// added in state with just the given charm URL and
// PendingUpload=true, which is then returned as a *state.Charm.
//
// The url's schema must be "cs" and it must include a revision.
func (st *State) PrepareStoreCharmUpload(curl *charm.URL) (*Charm, error) {
// Perform a few sanity checks first.
if curl.Schema != "cs" {
return nil, fmt.Errorf("expected charm URL with cs schema, got %q", curl)
}
if curl.Revision < 0 {
return nil, fmt.Errorf("expected charm URL with revision, got %q", curl)
}
var (
uploadedCharm charmDoc
err error
)
for attempt := 0; attempt < 3; attempt++ {
// Find an uploaded or pending charm with the given exact curl.
err = st.charms.FindId(curl).One(&uploadedCharm)
if err != nil && err != mgo.ErrNotFound {
return nil, err
} else if err == nil && !uploadedCharm.Placeholder {
// The charm exists and it's either uploaded or still
// pending, but it's not a placeholder. In any case, we
// just return what we got.
return newCharm(st, &uploadedCharm)
} else if err == mgo.ErrNotFound {
// Prepare the pending charm document for insertion.
uploadedCharm = charmDoc{
URL: curl,
PendingUpload: true,
Placeholder: false,
}
}
var ops []txn.Op
if uploadedCharm.Placeholder {
// Convert the placeholder to a pending charm, while
// asserting the fields updated after an upload have not
// changed yet.
ops = []txn.Op{{
C: st.charms.Name,
Id: curl,
Assert: bson.D{
{"bundlesha256", ""},
{"pendingupload", false},
{"placeholder", true},
},
Update: bson.D{{"$set", bson.D{
{"pendingupload", true},
{"placeholder", false},
}}},
}}
// Update the fields of the document we're returning.
uploadedCharm.PendingUpload = true
uploadedCharm.Placeholder = false
} else {
// No charm document with this curl yet, insert it.
ops = []txn.Op{{
C: st.charms.Name,
Id: curl,
Assert: txn.DocMissing,
Insert: uploadedCharm,
}}
}
// Run the transaction, and retry on abort.
err = st.runTransaction(ops)
if err == txn.ErrAborted {
continue
} else if err != nil {
return nil, err
} else if err == nil {
return newCharm(st, &uploadedCharm)
}
}
return nil, ErrExcessiveContention
}
var (
stillPending = bson.D{{"pendingupload", true}}
stillPlaceholder = bson.D{{"placeholder", true}}
)
// AddStoreCharmPlaceholder creates a charm document in state for the given charm URL which
// must reference a charm from the store. The charm document is marked as a placeholder which
// means that if the charm is to be deployed, it will need to first be uploaded to env storage.
func (st *State) AddStoreCharmPlaceholder(curl *charm.URL) (err error) {
// Perform sanity checks first.
if curl.Schema != "cs" {
return fmt.Errorf("expected charm URL with cs schema, got %q", curl)
}
if curl.Revision < 0 {
return fmt.Errorf("expected charm URL with revision, got %q", curl)
}
for attempt := 0; attempt < 3; attempt++ {
// See if the charm already exists in state and exit early if that's the case.
var doc charmDoc
err = st.charms.Find(bson.D{{"_id", curl.String()}}).Select(bson.D{{"_id", 1}}).One(&doc)
if err != nil && err != mgo.ErrNotFound {
return err
}
if err == nil {
return nil
}
// Delete all previous placeholders so we don't fill up the database with unused data.
var ops []txn.Op
ops, err = st.deleteOldPlaceholderCharmsOps(curl)
if err != nil {
return nil
}
// Add the new charm doc.
placeholderCharm := &charmDoc{
URL: curl,
Placeholder: true,
}
ops = append(ops, txn.Op{
C: st.charms.Name,
Id: placeholderCharm.URL.String(),
Assert: txn.DocMissing,
Insert: placeholderCharm,
})
// Run the transaction, and retry on abort.
if err = st.runTransaction(ops); err == txn.ErrAborted {
continue
} else if err != nil {
return err
}
break
}
if err != nil {
return ErrExcessiveContention
}
return nil
}
// deleteOldPlaceholderCharmsOps returns the txn ops required to delete all placeholder charm
// records older than the specified charm URL.
func (st *State) deleteOldPlaceholderCharmsOps(curl *charm.URL) ([]txn.Op, error) {
// Get a regex with the charm URL and no revision.
noRevURL := curl.WithRevision(-1)
curlRegex := "^" + regexp.QuoteMeta(noRevURL.String())
var docs []charmDoc
err := st.charms.Find(
bson.D{{"_id", bson.D{{"$regex", curlRegex}}}, {"placeholder", true}}).Select(bson.D{{"_id", 1}}).All(&docs)
if err != nil {
return nil, err
}
var ops []txn.Op
for _, doc := range docs {
if doc.URL.Revision >= curl.Revision {
continue
}
ops = append(ops, txn.Op{
C: st.charms.Name,
Id: doc.URL.String(),
Assert: stillPlaceholder,
Remove: true,
})
}
return ops, nil
}
// ErrCharmAlreadyUploaded is returned by UpdateUploadedCharm() when
// the given charm is already uploaded and marked as not pending in
// state.
type ErrCharmAlreadyUploaded struct {
curl *charm.URL
}
func (e *ErrCharmAlreadyUploaded) Error() string {
return fmt.Sprintf("charm %q already uploaded", e.curl)
}
// IsCharmAlreadyUploadedError returns if the given error is
// ErrCharmAlreadyUploaded.
func IsCharmAlreadyUploadedError(err interface{}) bool {
if err == nil {
return false
}
_, ok := err.(*ErrCharmAlreadyUploaded)
return ok
}
// ErrCharmRevisionAlreadyModified is returned when a pending or
// placeholder charm is no longer pending or a placeholder, signaling
// the charm is available in state with its full information.
var ErrCharmRevisionAlreadyModified = fmt.Errorf("charm revision already modified")
// UpdateUploadedCharm marks the given charm URL as uploaded and
// updates the rest of its data, returning it as *state.Charm.
func (st *State) UpdateUploadedCharm(ch charm.Charm, curl *charm.URL, bundleURL *url.URL, bundleSha256 string) (*Charm, error) {
doc := &charmDoc{}
err := st.charms.FindId(curl).One(&doc)
if err == mgo.ErrNotFound {
return nil, errors.NotFoundf("charm %q", curl)
}
if err != nil {
return nil, err
}
if !doc.PendingUpload {
return nil, &ErrCharmAlreadyUploaded{curl}
}
return st.updateCharmDoc(ch, curl, bundleURL, bundleSha256, stillPending)
}
// updateCharmDoc updates the charm with specified URL with the given
// data, and resets the placeholder and pendingupdate flags. If the
// charm is no longer a placeholder or pending (depending on preReq),
// it returns ErrCharmRevisionAlreadyModified.
func (st *State) updateCharmDoc(
ch charm.Charm, curl *charm.URL, bundleURL *url.URL, bundleSha256 string, preReq interface{}) (*Charm, error) {
updateFields := bson.D{{"$set", bson.D{
{"meta", ch.Meta()},
{"config", ch.Config()},
{"bundleurl", bundleURL},
{"bundlesha256", bundleSha256},
{"pendingupload", false},
{"placeholder", false},
}}}
ops := []txn.Op{{
C: st.charms.Name,
Id: curl,
Assert: preReq,
Update: updateFields,
}}
if err := st.runTransaction(ops); err != nil {
return nil, onAbort(err, ErrCharmRevisionAlreadyModified)
}
return st.Charm(curl)
}
// addPeerRelationsOps returns the operations necessary to add the
// specified service peer relations to the state.
func (st *State) addPeerRelationsOps(serviceName string, peers map[string]charm.Relation) ([]txn.Op, error) {
var ops []txn.Op
for _, rel := range peers {
relId, err := st.sequence("relation")
if err != nil {
return nil, err
}
eps := []Endpoint{{
ServiceName: serviceName,
Relation: rel,
}}
relKey := relationKey(eps)
relDoc := &relationDoc{
Key: relKey,
Id: relId,
Endpoints: eps,
Life: Alive,
}
ops = append(ops, txn.Op{
C: st.relations.Name,
Id: relKey,
Assert: txn.DocMissing,
Insert: relDoc,
})
}
return ops, nil
}
// AddService creates a new service, running the supplied charm, with the
// supplied name (which must be unique). If the charm defines peer relations,
// they will be created automatically.
func (st *State) AddService(name, ownerTag string, ch *Charm, includeNetworks, excludeNetworks []string) (service *Service, err error) {
defer errors.Maskf(&err, "cannot add service %q", name)
kind, ownerId, err := names.ParseTag(ownerTag, names.UserTagKind)
if err != nil || kind != names.UserTagKind {
return nil, fmt.Errorf("Invalid ownertag %s", ownerTag)
}
// Sanity checks.
if !names.IsService(name) {
return nil, fmt.Errorf("invalid name")
}
if ch == nil {
return nil, fmt.Errorf("charm is nil")
}
if exists, err := isNotDead(st.services, name); err != nil {
return nil, err
} else if exists {
return nil, fmt.Errorf("service already exists")
}
env, err := st.Environment()
if err != nil {
return nil, err
} else if env.Life() != Alive {
return nil, fmt.Errorf("environment is no longer alive")
}
if userExists, err := st.checkUserExists(ownerId); err != nil {
return nil, err
} else if !userExists {
return nil, fmt.Errorf("user %v doesn't exist", ownerId)
}
// Create the service addition operations.
peers := ch.Meta().Peers
svcDoc := &serviceDoc{
Name: name,
Series: ch.URL().Series,
Subordinate: ch.Meta().Subordinate,
CharmURL: ch.URL(),
RelationCount: len(peers),
Life: Alive,
OwnerTag: ownerTag,
}
svc := newService(st, svcDoc)
ops := []txn.Op{
env.assertAliveOp(),
createConstraintsOp(st, svc.globalKey(), constraints.Value{}),
// TODO(dimitern) 2014-04-04 bug #1302498
// Once we can add networks independently of machine
// provisioning, we should check the given networks are valid
// and known before setting them.
createRequestedNetworksOp(st, svc.globalKey(), includeNetworks, excludeNetworks),
createSettingsOp(st, svc.settingsKey(), nil),
{
C: st.users.Name,
Id: ownerId,
Assert: txn.DocExists,
},
{
C: st.settingsrefs.Name,
Id: svc.settingsKey(),
Assert: txn.DocMissing,
Insert: settingsRefsDoc{1},
},
{
C: st.services.Name,
Id: name,
Assert: txn.DocMissing,
Insert: svcDoc,
}}
// Collect peer relation addition operations.
peerOps, err := st.addPeerRelationsOps(name, peers)
if err != nil {
return nil, err
}
ops = append(ops, peerOps...)
if err := st.runTransaction(ops); err == txn.ErrAborted {