// ProcessEvent reads, validates and emits a configuration.
func (b *configuratorBehavior) ProcessEvent(event cells.Event) error {
switch event.Topic() {
case ReadConfigurationTopic:
// Read configuration
filename, ok := event.Payload().GetString(ConfigurationFilenamePayload)
if !ok {
logger.Errorf("cannot read configuration without filename payload")
return nil
}
logger.Infof("reading configuration from %q", filename)
cfg, err := etc.ReadFile(filename)
if err != nil {
return errors.Annotate(err, ErrCannotReadConfiguration, errorMessages)
}
// If wanted then validate it.
if b.validate != nil {
err = b.validate(cfg)
if err != nil {
return errors.Annotate(err, ErrCannotValidateConfiguration, errorMessages)
}
}
// All done, emit it.
pvs := cells.PayloadValues{
ConfigurationPayload: cfg,
}
b.cell.EmitNewContext(ConfigurationTopic, pvs, event.Context())
}
return nil
}
// receiveResponse retrieves a response from the server.
func (r *resp) receiveResponse() *response {
// Receive first line.
line, err := r.reader.ReadBytes('\n')
if err != nil {
rerr := errors.Annotate(err, ErrConnectionBroken, errorMessages, "receive after "+r.cmd)
return &response{receivingError, 0, nil, rerr}
}
content := line[1 : len(line)-2]
// First byte defines kind.
switch line[0] {
case '+':
// Status response.
return &response{statusResponse, 0, line[:len(line)-2], nil}
case '-':
// Error response.
return &response{errorResponse, 0, line[:len(line)-2], nil}
case ':':
// Integer response.
return &response{integerResponse, 0, content, nil}
case '$':
// Bulk response or null bulk response.
count, err := strconv.Atoi(string(content))
if err != nil {
return &response{receivingError, 0, nil, errors.Annotate(err, ErrServerResponse, errorMessages)}
}
if count == -1 {
// Null bulk response.
return &response{nullBulkResponse, 0, nil, nil}
}
// Receive the bulk data.
toRead := count + 2
buffer := make([]byte, toRead)
n, err := io.ReadFull(r.reader, buffer)
if err != nil {
return &response{receivingError, 0, nil, err}
}
if n < toRead {
return &response{receivingError, 0, nil, errors.New(ErrServerResponse, errorMessages)}
}
return &response{bulkResponse, 0, buffer[0:count], nil}
case '*':
// Array reply. Check for timeout.
length, err := strconv.Atoi(string(content))
if err != nil {
return &response{receivingError, 0, nil, errors.Annotate(err, ErrServerResponse, errorMessages)}
}
if length == -1 {
// Timeout.
return &response{timeoutError, 0, nil, nil}
}
return &response{arrayResponse, length, nil, nil}
}
return &response{receivingError, 0, nil, errors.New(ErrInvalidResponse, errorMessages, string(line))}
}
// Read reads the SML source of the configuration from a
// reader, parses it, and returns the configuration instance.
func Read(source io.Reader) (Configuration, error) {
builder := sml.NewKeyStringValueTreeBuilder()
err := sml.ReadSML(source, builder)
if err != nil {
return nil, errors.Annotate(err, ErrIllegalSourceFormat, errorMessages)
}
tree, err := builder.Tree()
if err != nil {
return nil, errors.Annotate(err, ErrIllegalSourceFormat, errorMessages)
}
if err := tree.At("config").Error(); err != nil {
return nil, errors.Annotate(err, ErrIllegalSourceFormat, errorMessages)
}
return &configuration{tree}, nil
}
// ReadFile reads the SML source of a configuration file,
// parses it, and returns the configuration instance.
func ReadFile(filename string) (Configuration, error) {
source, err := ioutil.ReadFile(filename)
if err != nil {
return nil, errors.Annotate(err, ErrCannotReadFile, errorMessages, filename)
}
return ReadString(string(source))
}
// Post is specified on the PostResourceHandler interface.
func (h *FileUploadHandler) Post(ctx Context) (bool, error) {
if err := ctx.Request().ParseMultipartForm(defaultMaxMemory); err != nil {
return false, errors.Annotate(err, ErrUploadingFile, errorMessages)
}
for _, headers := range ctx.Request().MultipartForm.File {
for _, header := range headers {
logger.Infof("receiving file %q", header.Filename)
// Open file and process it.
if infile, err := header.Open(); err != nil {
return false, errors.Annotate(err, ErrUploadingFile, errorMessages)
} else if err := h.processor(ctx, header, infile); err != nil {
return false, errors.Annotate(err, ErrUploadingFile, errorMessages)
}
}
}
return true, nil
}
// DoAll implements the Set interface.
func (s *set) DoAll(f func(v interface{}) error) error {
for v := range s.values {
if err := f(v); err != nil {
return errors.Annotate(err, ErrDoAll, errorMessages)
}
}
return nil
}
// Validate checks if the GUID is valid.
func (g *GUID) Validate() error {
if g.IsPermaLink {
if _, err := url.Parse(g.GUID); err != nil {
return errors.Annotate(err, ErrParsing, errorMessages, "item GUID")
}
}
return nil
}
// selectDatabase selects the database.
func (r *resp) selectDatabase() error {
err := r.sendCommand("select", r.database.index)
if err != nil {
return errors.Annotate(err, ErrSelectDatabase, errorMessages)
}
result, err := r.receiveResultSet()
if err != nil {
return errors.Annotate(err, ErrSelectDatabase, errorMessages)
}
value, err := result.ValueAt(0)
if err != nil {
return errors.Annotate(err, ErrSelectDatabase, errorMessages)
}
if !value.IsOK() {
return errors.New(ErrSelectDatabase, errorMessages)
}
return nil
}
// Validate checks if the source is valid.
func (s *Source) Validate() error {
if s.Source == "" {
return errors.New(ErrValidation, errorMessages, "item source must not be empty")
}
if _, err := url.Parse(s.URL); err != nil {
return errors.Annotate(err, ErrParsing, errorMessages, "item source URL")
}
return nil
}
// authenticate authenticates against the server if configured.
func (r *resp) authenticate() error {
if r.database.password != "" {
err := r.sendCommand("auth", r.database.password)
if err != nil {
return errors.Annotate(err, ErrAuthenticate, errorMessages)
}
result, err := r.receiveResultSet()
if err != nil {
return errors.Annotate(err, ErrAuthenticate, errorMessages)
}
value, err := result.ValueAt(0)
if err != nil {
return errors.Annotate(err, ErrAuthenticate, errorMessages)
}
if !value.IsOK() {
return errors.New(ErrAuthenticate, errorMessages)
}
}
return nil
}
// cleanupAllProps cleans all props.
func (s *scene) cleanupAllProps() error {
for _, box := range s.props {
if box.cleanup != nil {
err := box.cleanup(box.key, box.prop)
if err != nil {
return errors.Annotate(err, ErrCleanupFailed, errorMessages, box.key)
}
}
}
return nil
}
// GetFloat64 implements the Value interface.
func (v *value) GetFloat64() (float64, error) {
raw, err := v.Get()
if err != nil {
return 0.0, err
}
fv, err := strconv.ParseFloat(raw, 64)
if err != nil {
return 0.0, errors.Annotate(err, ErrInvalidFormat, errorMessages, raw)
}
return fv, nil
}
// GetInt implements the Value interface.
func (v *value) GetInt() (int, error) {
raw, err := v.Get()
if err != nil {
return 0, err
}
iv, err := strconv.ParseInt(raw, 10, 0)
if err != nil {
return 0, errors.Annotate(err, ErrInvalidFormat, errorMessages, raw)
}
return int(iv), nil
}
// GetTime implements the Value interface.
func (v *value) GetTime() (time.Time, error) {
raw, err := v.Get()
if err != nil {
return time.Time{}, err
}
tv, err := time.Parse(time.RFC3339, raw)
if err != nil {
return tv, errors.Annotate(err, ErrInvalidFormat, errorMessages, raw)
}
return tv, nil
}
// GetBool implements the Value interface.
func (v *value) GetBool() (bool, error) {
raw, err := v.Get()
if err != nil {
return false, err
}
bv, err := strconv.ParseBool(raw)
if err != nil {
return false, errors.Annotate(err, ErrInvalidFormat, errorMessages, raw)
}
return bv, nil
}
// GetDuration implements the Value interface.
func (v *value) GetDuration() (time.Duration, error) {
raw, err := v.Get()
if err != nil {
return time.Duration(0), err
}
dv, err := time.ParseDuration(raw)
if err != nil {
return dv, errors.Annotate(err, ErrInvalidFormat, errorMessages, raw)
}
return dv, nil
}
// newCell create a new cell around a behavior.
func newCell(env *environment, id string, behavior Behavior) (*cell, error) {
logger.Infof("cell '%s' starts", id)
// Init cell runtime.
c := &cell{
env: env,
id: id,
measuringID: identifier.Identifier("cells", env.id, "cell", id),
behavior: behavior,
emitters: newConnections(),
subscribers: newConnections(),
emitTimeoutTicker: time.NewTicker(5 * time.Second),
}
// Set configuration.
if bebs, ok := behavior.(BehaviorEventBufferSize); ok {
size := bebs.EventBufferSize()
if size < minEventBufferSize {
size = minEventBufferSize
}
c.eventc = make(chan Event, size)
} else {
c.eventc = make(chan Event, minEventBufferSize)
}
if brf, ok := behavior.(BehaviorRecoveringFrequency); ok {
number, duration := brf.RecoveringFrequency()
if duration.Seconds()/float64(number) < 0.1 {
number = minRecoveringNumber
duration = minRecoveringDuration
}
c.recoveringNumber = number
c.recoveringDuration = duration
} else {
c.recoveringNumber = minRecoveringNumber
c.recoveringDuration = minRecoveringDuration
}
if bet, ok := behavior.(BehaviorEmitTimeout); ok {
timeout := bet.EmitTimeout()
switch {
case timeout < minEmitTimeout:
timeout = minEmitTimeout
case timeout > maxEmitTimeout:
timeout = maxEmitTimeout
}
c.emitTimeout = int(timeout.Seconds() / 5)
} else {
c.emitTimeout = int(maxEmitTimeout.Seconds() / 5)
}
// Init behavior.
if err := behavior.Init(c); err != nil {
return nil, errors.Annotate(err, ErrCellInit, errorMessages, id)
}
// Start backend.
c.loop = loop.GoRecoverable(c.backendLoop, c.checkRecovering, id)
return c, nil
}
// Validate checks if the enclosure is valid.
func (e *Enclosure) Validate() error {
if e.Length < 1 {
return errors.New(ErrValidation, errorMessages, "item enclosure length %d is too small", e.Length)
}
if e.Type == "" {
return errors.New(ErrValidation, errorMessages, "item enclosure type must not be empty")
}
if _, err := url.Parse(e.URL); err != nil {
return errors.Annotate(err, ErrParsing, errorMessages, "item enclosure url")
}
return nil
}
// NewUUIDByHex creates a UUID based on the passed hex string which has to
// have the length of 32 bytes.
func NewUUIDByHex(source string) (UUID, error) {
uuid := UUID{}
if len([]byte(source)) != 32 {
return uuid, errors.New(ErrInvalidHexLength, errorMessages)
}
raw, err := hex.DecodeString(source)
if err != nil {
return uuid, errors.Annotate(err, ErrInvalidHexValue, errorMessages)
}
copy(uuid[:], raw)
return uuid, nil
}
// checkRecovering checks if the cell may recover after a panic. It will
// signal an error and let the cell stop working if there have been 12 recoverings
// during the last minute or the behaviors Recover() signals, that it cannot
// handle the error.
func (c *cell) checkRecovering(rs loop.Recoverings) (loop.Recoverings, error) {
logger.Errorf("recovering cell %q after error: %v", c.id, rs.Last().Reason)
// Check frequency.
if rs.Frequency(c.recoveringNumber, c.recoveringDuration) {
return nil, errors.New(ErrRecoveredTooOften, errorMessages, rs.Last().Reason)
}
// Try to recover.
if err := c.behavior.Recover(rs.Last().Reason); err != nil {
return nil, errors.Annotate(err, ErrEventRecovering, errorMessages, rs.Last().Reason)
}
return rs.Trim(c.recoveringNumber), nil
}
// newResp establishes a connection to a Redis database
// based on the configuration of the passed database
// configuration.
func newResp(db *Database) (*resp, error) {
// Dial the database and create the protocol instance.
conn, err := net.DialTimeout(db.network, db.address, db.timeout)
if err != nil {
return nil, errors.Annotate(err, ErrConnectionEstablishing, errorMessages)
}
r := &resp{
database: db,
conn: conn,
reader: bufio.NewReader(conn),
}
return r, nil
}
// Test the annotation of errors.
func TestAnnotation(t *testing.T) {
assert := audit.NewTestingAssertion(t, true)
ec := 123
messages := errors.Messages{ec: "annotated"}
aerr := testError("wrapped")
err := errors.Annotate(aerr, ec, messages)
assert.ErrorMatch(err, `\[ERRORS_TEST:123\] annotated: wrapped`)
assert.Equal(errors.Annotated(err), aerr)
assert.True(errors.IsInvalidTypeError(errors.Annotated(aerr)))
assert.Length(errors.Stack(err), 2)
}
// FindAll implements the Set interface.
func (s *set) FindAll(f func(v interface{}) (bool, error)) ([]interface{}, error) {
found := []interface{}{}
for v := range s.values {
ok, err := f(v)
if err != nil {
return nil, errors.Annotate(err, ErrFindAll, errorMessages)
}
if ok {
found = append(found, v)
}
}
return found, nil
}
// FindAll implements the StringSet interface.
func (s *stringSet) FindAll(f func(v string) (bool, error)) ([]string, error) {
found := []string{}
for v := range s.values {
ok, err := f(v)
if err != nil {
return nil, errors.Annotate(err, ErrFindAll, errorMessages)
}
if ok {
found = append(found, v)
}
}
return found, nil
}
// sendCommand sends a command and possible arguments to the server.
func (r *resp) sendCommand(cmd string, args ...interface{}) error {
r.cmd = cmd
lengthPart := r.buildLengthPart(args)
cmdPart := r.buildValuePart(cmd)
argsPart := r.buildArgumentsPart(args)
packet := join(lengthPart, cmdPart, argsPart)
_, err := r.conn.Write(packet)
if err != nil {
return errors.Annotate(err, ErrConnectionBroken, errorMessages, "send "+r.cmd)
}
return nil
}
// Apply implements the Configuration interface.
func (c *configuration) Apply(kvs map[string]string) (Configuration, error) {
cc := &configuration{
values: c.values.Copy(),
}
for key, value := range kvs {
path := append([]string{"config"}, strings.Split(key, "/")...)
_, err := cc.values.Create(path...).SetValue(value)
if err != nil {
return nil, errors.Annotate(err, ErrCannotApply, errorMessages)
}
}
return cc, nil
}
// Validate checks if the item is valid.
func (i *Item) Validate() error {
if i.Title == "" {
if i.Description == "" {
return errors.New(ErrValidation, errorMessages, "item title or description must not be empty")
}
}
if i.Comments != "" {
if _, err := url.Parse(i.Comments); err != nil {
return errors.Annotate(err, ErrParsing, errorMessages, "item comments")
}
}
if i.Enclosure != nil {
if err := i.Enclosure.Validate(); err != nil {
return err
}
}
if i.GUID != nil {
if err := i.GUID.Validate(); err != nil {
return err
}
}
if i.Link != "" {
if _, err := url.Parse(i.Link); err != nil {
return errors.Annotate(err, ErrParsing, errorMessages, "item link")
}
}
if i.PubDate != "" {
if _, err := ParseTime(i.PubDate); err != nil {
return errors.Annotate(err, ErrParsing, errorMessages, "item publcation date")
}
}
if i.Source != nil {
if err := i.Source.Validate(); err != nil {
return err
}
}
return nil
}
// Validate checks if the text input is valid.
func (t *TextInput) Validate() error {
if t.Description == "" {
return errors.New(ErrValidation, errorMessages, "text input description must not be empty")
}
if _, err := url.Parse(t.Link); err != nil {
return errors.Annotate(err, ErrParsing, errorMessages, "text input link")
}
if t.Name == "" {
return errors.New(ErrValidation, errorMessages, "text input name must not be empty")
}
if t.Title == "" {
return errors.New(ErrValidation, errorMessages, "text input title must not be empty")
}
return nil
}
// TextNode implements the Builder interface.
func (tb *KeyStringValueTreeBuilder) TextNode(text string) error {
if tb.done {
return errors.New(ErrBuilder, errorMessages, "building is already done")
}
value, err := tb.tree.At(tb.stack.All()...).Value()
if err != nil {
return errors.Annotate(err, ErrBuilder, errorMessages)
}
if value != "" {
return errors.New(ErrBuilder, errorMessages, "node has multiple values")
}
text = strings.TrimSpace(text)
if text != "" {
_, err = tb.tree.At(tb.stack.All()...).SetValue(text)
}
return err
}
// checkRecovering checks if the cell may recover after a panic. It will
// signal an error and let the cell stop working if there have been 12 recoverings
// during the last minute or the behaviors Recover() signals, that it cannot
// handle the error.
func (c *cell) checkRecovering(rs loop.Recoverings) (loop.Recoverings, error) {
logger.Warningf("recovering cell %q after error: %v", c.id, rs.Last().Reason)
// Check frequency.
if rs.Frequency(c.recoveringNumber, c.recoveringDuration) {
err := errors.New(ErrRecoveredTooOften, errorMessages, rs.Last().Reason)
logger.Errorf("recovering frequency of cell %q too high", c.id)
return nil, err
}
// Try to recover.
if err := c.behavior.Recover(rs.Last().Reason); err != nil {
err := errors.Annotate(err, ErrEventRecovering, errorMessages, rs.Last().Reason)
logger.Errorf("recovering of cell %q failed: %v", c.id, err)
return nil, err
}
logger.Infof("successfully recovered cell %q", c.id)
return rs.Trim(c.recoveringNumber), nil
}