When we see an `ECONNREFUSED` (or equivalent) from an attempted `HEAD` on the
`/_ping` endpoint there is no point in trying again with `GET` since the server
is not responding/available at all.
Once vendored into the cli this will partially mitigate https://github.com/docker/cli/issues/1739
("Docker commands take 1 minute to timeout if context endpoint is unreachable")
by cutting the effective timeout in half.
Signed-off-by: Ian Campbell <ijc@docker.com>
(cherry picked from commit 8c8457b0f2)
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
WithAPIVersionNegotiation enables automatic API version negotiation for the client.
With this option enabled, the client automatically negotiates the API version
to use when making requests. API version negotiation is performed on the first
request; subsequent requests will not re-negotiate.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
commit 3d72963ab8 fixed
situations where a version negotiation could override
the version, even though a client was initialized with a
fixed version.
In situations where the "fixed" version is empty, we
should ignore the option, and treat the client as
"not having a fixed version", so that API version
negotiation can still be performed.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Minor improvement, but makes defining a list of options
a bit cleaner, and more descriptive;
Before:
opts := make([]func(*client.Client) error, 0)
After:
opts := make([]client.Opt, 0)
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Unlike a plain `net/http/client.Do()`, requests made through client/request
use the `sendRequest` function, which parses the server response, and may
convert non-transport errors into errors (through `cli.checkResponseErr()`).
This means that we cannot assume that no reader was opened if an error is
returned.
This patch changes various locations where `ensureReaderClosed` was only
called in the non-error situation, and uses a `defer` to make sure it's
always called.
`ensureReaderClosed` itself already checks if the response's body was set,
so in situations where the error was due to a transport error, calling
`ensureReaderClosed` should be a no-op.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
looks like we don't need this handling
Before this patch:
Error: No such image: nosuchimage
After this patch:
Error response from daemon: No such image: nosuchimage:latest
"
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Monitoring systems and load balancers are usually configured to use HEAD
requests for health monitoring. The /_ping endpoint currently does not
support this type of request, which means that those systems have fallback
to GET requests.
This patch adds support for HEAD requests on the /_ping endpoint.
Although optional, this patch also returns `Content-Type` and `Content-Length`
headers in case of a HEAD request; Refering to RFC 7231, section 4.3.2:
The HEAD method is identical to GET except that the server MUST NOT
send a message body in the response (i.e., the response terminates at
the end of the header section). The server SHOULD send the same
header fields in response to a HEAD request as it would have sent if
the request had been a GET, except that the payload header fields
(Section 3.3) MAY be omitted. This method can be used for obtaining
metadata about the selected representation without transferring the
representation data and is often used for testing hypertext links for
validity, accessibility, and recent modification.
A payload within a HEAD request message has no defined semantics;
sending a payload body on a HEAD request might cause some existing
implementations to reject the request.
The response to a HEAD request is cacheable; a cache MAY use it to
satisfy subsequent HEAD requests unless otherwise indicated by the
Cache-Control header field (Section 5.2 of [RFC7234]). A HEAD
response might also have an effect on previously cached responses to
GET; see Section 4.3.5 of [RFC7234].
With this patch applied, either `GET` or `HEAD` requests work; the only
difference is that the body is empty in case of a `HEAD` request;
curl -i --unix-socket /var/run/docker.sock http://localhost/_ping
HTTP/1.1 200 OK
Api-Version: 1.40
Cache-Control: no-cache, no-store, must-revalidate
Docker-Experimental: false
Ostype: linux
Pragma: no-cache
Server: Docker/dev (linux)
Date: Mon, 14 Jan 2019 12:35:16 GMT
Content-Length: 2
Content-Type: text/plain; charset=utf-8
OK
curl --head -i --unix-socket /var/run/docker.sock http://localhost/_ping
HTTP/1.1 200 OK
Api-Version: 1.40
Cache-Control: no-cache, no-store, must-revalidate
Content-Length: 0
Content-Type: text/plain; charset=utf-8
Docker-Experimental: false
Ostype: linux
Pragma: no-cache
Server: Docker/dev (linux)
Date: Mon, 14 Jan 2019 12:34:15 GMT
The client is also updated to use `HEAD` by default, but fallback to `GET`
if the daemon does not support this method.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Currently, the behaviour for the version field in ServiceUpdate()
is vague. Without an correct version number, users are unable to
successfully run ServiceUpdate(), which is a pretty critical method
for scaling services (for example). I've just added an extra sentence
explaining what the version number is for, and where to find it.
Signed-off-by: Harrison Turton <harrisonturton@gmail.com>
client.checkResponseErr() was hanging and consuming infinite memory
when the serverResp.Body io.Reader returns infinite stream.
This commit prohibits reading more than 1MiB.
Signed-off-by: Akihiro Suda <suda.akihiro@lab.ntt.co.jp>
WithDialContext() allows specifying custom dialer for hijacking and supposed to
replace WithDialer().
WithDialer() is also updated to use WithDialContext().
client.Dialer() returns the dialer configured with WithDialContext().
Signed-off-by: Akihiro Suda <suda.akihiro@lab.ntt.co.jp>
This partially reverts https://github.com/moby/moby/pull/37350
Although specs.Platform is desirable in the API, there is more work
to be done on helper functions, namely containerd's platforms.Parse
that assumes the default platform of the Go runtime.
That prevents a client to use the recommended Parse function to
retrieve a specs.Platform object.
With this change, no parsing is expected from the client.
Signed-off-by: Tibor Vass <tibor@docker.com>
Since go1.8, the stdlib TLS net.Conn implementation implements the
`CloseWrite()` interface.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
