Files
kata-containers/vendor/github.com/uber/jaeger-client-go/thrift/protocol.go
James O. D. Hunt 3a1bbd0271 tracing: Add initial opentracing support
Add initial support for opentracing by using the `jaeger` package.
Since opentracing uses the `context` package, add a `context.Context`
as the first parameter to all the functions that we might want to
trace. Trace "spans" (trace points) are then added by extracting the
trace details from the specified context parameter.

Notes:

- Although the tracer is created in `main()`, the "root span"
  (aka the first trace point) is not added until `beforeSubcommands()`.

  This is by design and is a compromise: by delaying the creation of the
  root span, the spans become much more readable since using the web-based
  JaegerUI, you will see traces like this:

  ```
  kata-runtime: kata-runtime create
  ------------  -------------------
       ^                ^
       |                |
  Trace name        First span name
                    (which clearly shows the CLI command that was run)
  ```

  Creating the span earlier means it is necessary to expand 'n' spans in
  the UI before you get to see the name of the CLI command that was run.
  In adding support, this became very tedious, hence my design decision to
  defer the creation of the root span until after signal handling has been
  setup and after CLI options have been parsed, but still very early in
  the code path.

  - At this stage, the tracing stops at the `virtcontainers` call
  boundary.

- Tracing is "always on" as there doesn't appear to be a way to toggle
  it. However, its resolves to a "nop" unless the tracer can talk to a
  jaeger agent.

Note that this commit required a bit of rework to `beforeSubcommands()`
to reduce the cyclomatic complexity.

Fixes #557.

Signed-off-by: James O. D. Hunt <james.o.hunt@intel.com>
2018-08-10 16:13:48 +01:00

176 lines
4.5 KiB
Go

/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package thrift
import (
"errors"
)
const (
VERSION_MASK = 0xffff0000
VERSION_1 = 0x80010000
)
type TProtocol interface {
WriteMessageBegin(name string, typeId TMessageType, seqid int32) error
WriteMessageEnd() error
WriteStructBegin(name string) error
WriteStructEnd() error
WriteFieldBegin(name string, typeId TType, id int16) error
WriteFieldEnd() error
WriteFieldStop() error
WriteMapBegin(keyType TType, valueType TType, size int) error
WriteMapEnd() error
WriteListBegin(elemType TType, size int) error
WriteListEnd() error
WriteSetBegin(elemType TType, size int) error
WriteSetEnd() error
WriteBool(value bool) error
WriteByte(value int8) error
WriteI16(value int16) error
WriteI32(value int32) error
WriteI64(value int64) error
WriteDouble(value float64) error
WriteString(value string) error
WriteBinary(value []byte) error
ReadMessageBegin() (name string, typeId TMessageType, seqid int32, err error)
ReadMessageEnd() error
ReadStructBegin() (name string, err error)
ReadStructEnd() error
ReadFieldBegin() (name string, typeId TType, id int16, err error)
ReadFieldEnd() error
ReadMapBegin() (keyType TType, valueType TType, size int, err error)
ReadMapEnd() error
ReadListBegin() (elemType TType, size int, err error)
ReadListEnd() error
ReadSetBegin() (elemType TType, size int, err error)
ReadSetEnd() error
ReadBool() (value bool, err error)
ReadByte() (value int8, err error)
ReadI16() (value int16, err error)
ReadI32() (value int32, err error)
ReadI64() (value int64, err error)
ReadDouble() (value float64, err error)
ReadString() (value string, err error)
ReadBinary() (value []byte, err error)
Skip(fieldType TType) (err error)
Flush() (err error)
Transport() TTransport
}
// The maximum recursive depth the skip() function will traverse
const DEFAULT_RECURSION_DEPTH = 64
// Skips over the next data element from the provided input TProtocol object.
func SkipDefaultDepth(prot TProtocol, typeId TType) (err error) {
return Skip(prot, typeId, DEFAULT_RECURSION_DEPTH)
}
// Skips over the next data element from the provided input TProtocol object.
func Skip(self TProtocol, fieldType TType, maxDepth int) (err error) {
if maxDepth <= 0 {
return NewTProtocolExceptionWithType( DEPTH_LIMIT, errors.New("Depth limit exceeded"))
}
switch fieldType {
case STOP:
return
case BOOL:
_, err = self.ReadBool()
return
case BYTE:
_, err = self.ReadByte()
return
case I16:
_, err = self.ReadI16()
return
case I32:
_, err = self.ReadI32()
return
case I64:
_, err = self.ReadI64()
return
case DOUBLE:
_, err = self.ReadDouble()
return
case STRING:
_, err = self.ReadString()
return
case STRUCT:
if _, err = self.ReadStructBegin(); err != nil {
return err
}
for {
_, typeId, _, _ := self.ReadFieldBegin()
if typeId == STOP {
break
}
err := Skip(self, typeId, maxDepth-1)
if err != nil {
return err
}
self.ReadFieldEnd()
}
return self.ReadStructEnd()
case MAP:
keyType, valueType, size, err := self.ReadMapBegin()
if err != nil {
return err
}
for i := 0; i < size; i++ {
err := Skip(self, keyType, maxDepth-1)
if err != nil {
return err
}
self.Skip(valueType)
}
return self.ReadMapEnd()
case SET:
elemType, size, err := self.ReadSetBegin()
if err != nil {
return err
}
for i := 0; i < size; i++ {
err := Skip(self, elemType, maxDepth-1)
if err != nil {
return err
}
}
return self.ReadSetEnd()
case LIST:
elemType, size, err := self.ReadListBegin()
if err != nil {
return err
}
for i := 0; i < size; i++ {
err := Skip(self, elemType, maxDepth-1)
if err != nil {
return err
}
}
return self.ReadListEnd()
}
return nil
}