Moving all strings to the errors package wasn't a good idea after all.
Our custom implementation of Go errors predates everything that's nice
and good about working with errors in Go. Take as an example what we
have to do to get an error message:
```go
func GetErrorMessage(err error) string {
switch err.(type) {
case errcode.Error:
e, _ := err.(errcode.Error)
return e.Message
case errcode.ErrorCode:
ec, _ := err.(errcode.ErrorCode)
return ec.Message()
default:
return err.Error()
}
}
```
This goes against every good practice for Go development. The language already provides a simple, intuitive and standard way to get error messages, that is calling the `Error()` method from an error. Reinventing the error interface is a mistake.
Our custom implementation also makes very hard to reason about errors, another nice thing about Go. I found several (>10) error declarations that we don't use anywhere. This is a clear sign about how little we know about the errors we return. I also found several error usages where the number of arguments was different than the parameters declared in the error, another clear example of how difficult is to reason about errors.
Moreover, our custom implementation didn't really make easier for people to return custom HTTP status code depending on the errors. Again, it's hard to reason about when to set custom codes and how. Take an example what we have to do to extract the message and status code from an error before returning a response from the API:
```go
switch err.(type) {
case errcode.ErrorCode:
daError, _ := err.(errcode.ErrorCode)
statusCode = daError.Descriptor().HTTPStatusCode
errMsg = daError.Message()
case errcode.Error:
// For reference, if you're looking for a particular error
// then you can do something like :
// import ( derr "github.com/docker/docker/errors" )
// if daError.ErrorCode() == derr.ErrorCodeNoSuchContainer { ... }
daError, _ := err.(errcode.Error)
statusCode = daError.ErrorCode().Descriptor().HTTPStatusCode
errMsg = daError.Message
default:
// This part of will be removed once we've
// converted everything over to use the errcode package
// FIXME: this is brittle and should not be necessary.
// If we need to differentiate between different possible error types,
// we should create appropriate error types with clearly defined meaning
errStr := strings.ToLower(err.Error())
for keyword, status := range map[string]int{
"not found": http.StatusNotFound,
"no such": http.StatusNotFound,
"bad parameter": http.StatusBadRequest,
"conflict": http.StatusConflict,
"impossible": http.StatusNotAcceptable,
"wrong login/password": http.StatusUnauthorized,
"hasn't been activated": http.StatusForbidden,
} {
if strings.Contains(errStr, keyword) {
statusCode = status
break
}
}
}
```
You can notice two things in that code:
1. We have to explain how errors work, because our implementation goes against how easy to use Go errors are.
2. At no moment we arrived to remove that `switch` statement that was the original reason to use our custom implementation.
This change removes all our status errors from the errors package and puts them back in their specific contexts.
IT puts the messages back with their contexts. That way, we know right away when errors used and how to generate their messages.
It uses custom interfaces to reason about errors. Errors that need to response with a custom status code MUST implementent this simple interface:
```go
type errorWithStatus interface {
HTTPErrorStatusCode() int
}
```
This interface is very straightforward to implement. It also preserves Go errors real behavior, getting the message is as simple as using the `Error()` method.
I included helper functions to generate errors that use custom status code in `errors/errors.go`.
By doing this, we remove the hard dependency we have eeverywhere to our custom errors package. Yes, you can use it as a helper to generate error, but it's still very easy to generate errors without it.
Please, read this fantastic blog post about errors in Go: http://dave.cheney.net/2014/12/24/inspecting-errors
Signed-off-by: David Calavera <david.calavera@gmail.com>
In Docker 1.10 and earlier, "docker build" can do a build FROM a private
repository that hasn't yet been pulled. This doesn't work on master. I
bisected this to https://github.com/docker/docker/pull/19414.
AuthConfigs is deserialized from the HTTP request, but not included in
the builder options.
Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>
This is done by moving the following types to api/types/config.go:
- ContainersConfig
- ContainerAttachWithLogsConfig
- ContainerWsAttachWithLogsConfig
- ContainerLogsConfig
- ContainerStatsConfig
Remove dependency on "version" package from types.ContainerStatsConfig.
Decouple the "container" router from the "daemon/exec" implementation.
* This is done by making daemon.ContainerExecInspect() return an interface{}
value. The same trick is already used by daemon.ContainerInspect().
Improve documentation for router packages.
Extract localRoute and router into separate files.
Move local.router to image.imageRouter.
Changes:
- Move local/image.go to image/image_routes.go.
- Move local/local.go to image/image.go
- Rename router to imageRouter.
- Simplify imports for image/image.go (remove alias for router package).
Merge router/local package into router package.
Decouple the "image" router from the actual daemon implementation.
Add Daemon.GetNetworkByID and Daemon.GetNetworkByName.
Decouple the "network" router from the actual daemon implementation.
This is done by replacing the daemon.NetworkByName constant with
an explicit GetNetworkByName method.
Remove the unused Daemon.GetNetwork method and the associated constants NetworkByID and NetworkByName.
Signed-off-by: Lukas Waslowski <cr7pt0gr4ph7@gmail.com>
Signed-off-by: David Calavera <david.calavera@gmail.com>
Currently, daemonbuilder package (part of daemon) implemented the
builder backend. However, it was a very thin wrapper around daemon
methods and caused an implementation dependency for api/server build
endpoint. api/server buildrouter should only know about the backend
implementing the /build API endpoint.
Removing daemonbuilder involved moving build specific methods to
respective files in the daemon, where they fit naturally.
Signed-off-by: Anusha Ragunathan <anusha@docker.com>
This is happening now due to improvements in net/http:
99fb19194c
To test, change the go version in the Dockerfile:
-ENV GO_VERSION 1.5.3
+ENV GO_VERSION 1.6beta2
More info here: https://github.com/golang/go/issues/14001
Signed-off-by: Christy Perez <christy@linux.vnet.ibm.com>
Currently builder.Backend is implemented by daemonbuilder.Docker{} for
the daemon. This registration happens in the API/server code. However,
this is too implementation specific. Ideally we should be able to specify
that docker daemon (or any other) is implementing the Backend and abstract
the implementation details. So we should remove package daemonbuilder
dependency in build_routes.go
With this change, daemonbuilder.Docker is nothing more than the daemon.
A follow on change will remove the daemonbuilder package and move relevant
methods under daemon, so that API only knows about the backend.
Also cleanup code in api/client/build.go. docker cli always performs build
context tar download for remoteURLs and sends an empty remoteContext. So
remove relevant dead code.
Signed-off-by: Anusha Ragunathan <anusha@docker.com>
dockerfile.Config is almost redundant with ImageBuildOptions.
Unify the two so that the latter can be removed. This also
helps build's API endpoint code to be less dependent on package
dockerfile.
Signed-off-by: Anusha Ragunathan <anusha@docker.com>
- Make the API client library completely standalone.
- Move windows partition isolation detection to the client, so the
driver doesn't use external types.
Signed-off-by: David Calavera <david.calavera@gmail.com>
Right now, the quiet (-q, --quiet) flag ignores the output
generated from within the container.
However, it ought to be quiet in a way that all kind
of diagnostic output should be ignored, unless the build
process fails.
This patch makes the quiet flag behave in the following way:
1. If the build process succeeds, stdout contains the image ID
and stderr is empty.
2. If the build process fails, stdout is empty and stderr
has the error message and the diagnostic output of that process.
If the quiet flag is not set, then everything goes to stdout
and error messages, if there are any, go to stderr.
Signed-off-by: Boaz Shuster <ripcurld.github@gmail.com>
