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>
dockerinit has been around for a very long time. It was originally used
as a way for us to do configuration for LXC containers once the
container had started. LXC is no longer supported, and /.dockerinit has
been dead code for quite a while. This removes all code and references
in code to dockerinit.
Signed-off-by: Aleksa Sarai <asarai@suse.com>
Add distribution package for managing pulls and pushes. This is based on
the old code in the graph package, with major changes to work with the
new image/layer model.
Add v1 migration code.
Update registry, api/*, and daemon packages to use the reference
package's types where applicable.
Update daemon package to use image/layer/tag stores instead of the graph
package
Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>
Signed-off-by: Tonis Tiigi <tonistiigi@gmail.com>
This reverts commit d5cd032a86.
Commit caused issues on systems with case-insensitive filesystems.
Revert for now
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
- Move autogen/dockerversion to version
- Update autogen and "builds" to use this package and a build flag
Signed-off-by: Vincent Demeester <vincent@sbr.pm>
This patch creates interfaces in builder/ for building Docker images.
It is a first step in a series of patches to remove the daemon
dependency on builder and later allow a client-side Dockerfile builder
as well as potential builder plugins.
It is needed because we cannot remove the /build API endpoint, so we
need to keep the server-side Dockerfile builder, but we also want to
reuse the same Dockerfile parser and evaluator for both server-side and
client-side.
builder/dockerfile/ and api/server/builder.go contain implementations
of those interfaces as a refactoring of the current code.
Signed-off-by: Tibor Vass <tibor@docker.com>
This is the first step in converting out static strings into well-defined
error types. This shows just a few examples of it to get a feel for how things
will look. Once we agree on the basic outline we can then work on converting
the rest of the code over.
Signed-off-by: Doug Davis <dug@us.ibm.com>
Updates most of the instances of HTTP urls in the engine's
comments. Does not account for any use in the code itself,
documentation, contrib, or project files.
Signed-off-by: Eric Windisch <eric@windisch.us>
Add ability to refer to an image by repository name and digest using the
format repository@digest. Works for pull, push, run, build, and rmi.
Signed-off-by: Andy Goldstein <agoldste@redhat.com>
Some calls like json.Encoder.Encode mask the number of bytes written to
an io.Writer. The solution provides a wrapper io.Writer around the
actual io.Writer that allows multiple calls to Write to be considered as
one and allow access to this count.
Signed-off-by: Pierre Wacrenier <pierre.wacrenier@gmail.com>
See #10141 for more info, but the main point of this is to make sure
that if you do "docker run -e FOO ..." that FOO from the current env
is passed into the container. This means that if there's a value, its
set. But it also means that if FOO isn't set then it should be unset in
the container too - even if it has to remove it from the env. So,
unset HOSTNAME
docker run -e HOSTNAME busybox env
should _NOT_ show HOSTNAME in the list at all
Closes#10141
Signed-off-by: Doug Davis <dug@us.ibm.com>
Only modifies non-running containers resolv.conf bind mount, and only if
the container has an unmodified resolv.conf compared to its contents at
container start time (so we don't overwrite manual/automated changes
within the container runtime). For containers which are running when
the host resolv.conf changes, the update will only be applied to the
container version of resolv.conf when the container is "bounced" down
and back up (e.g. stop/start or restart)
Docker-DCO-1.1-Signed-off-by: Phil Estes <estesp@linux.vnet.ibm.com> (github: estesp)
If .dockerignore mentions either then the client will send them to the
daemon but the daemon will erase them after the Dockerfile has been parsed
to simulate them never being sent in the first place.
an events test kept failing for me so I tried to fix that too
Closes#8330
Signed-off-by: Doug Davis <dug@us.ibm.com>
This moves the IsGIT and IsURL functions out of the generic `utils`
package and into their own `urlutil` pkg.
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
TreeSize uses syscall.Stat_t which is not available on Windows.
It's called only on daemon path, therefore extracting it to daemon
with build tag 'daemon'
Signed-off-by: Ahmet Alp Balkan <ahmetb@microsoft.com>
This will allow us to use a common Git prefix check for both api/clients/commands.go and
builder/job.go. Previous prefix check in build from Git (in builder/jobs.go) ignored valid prefixes such as "git@", "http://" or "https://".
Signed-off-by: Lakshan Perera <lakshan@laktek.com>
This is the second of two steps to break the archive package's
dependence on utils so that archive may be moved into pkg. `Matches()`
is also a good candidate pkg in that it is small, concise, and not
specific to docker internals
Signed-off-by: Rafe Colton <rafael.colton@gmail.com>
This is the first of two steps to break the archive package's dependence
on utils so that archive may be moved into pkg. Also, the `Go()`
function is small, concise, and not specific to the docker internals, so
it is a good candidate for pkg.
Signed-off-by: Rafe Colton <rafael.colton@gmail.com>
Since RemoveLocalDns patch will remove all localhost entries
from resolv.conf we no longer need anything more then
!bytes.Contains(resolvConf, []byte("nameserver")
To check for no nameserver entry in dns config.
Docker-DCO-1.1-Signed-off-by: Dan Walsh <dwalsh@redhat.com> (github: rhatdan)
