For tests (and perhaps later, for daemon discovery), unix domain sockets
offer advantages over TCP: we can know the exact socket address that will be
used when starting a server subprocess. They also offer performance and
security advantages over TCP, and were specifically requested on
golang.org/issues/34111.
This CL adds support for listening on UDS, and uses this to implement an
additional regtest environment mode that starts up an external process.
This mode is disabled by default, but may be enabled by the
-enable_gopls_subprocess_tests.
The regtest TestMain may be hijacked to instead run as gopls, if a
special environment variable is set. This allows the the test runner to
start a separate process by using os.Argv[0]. The -gopls_test_binary
flag may be used to point tests at a separate gopls binary.
Updates golang/go#36879
Updates golang/go#34111
Change-Id: I1cfdf55040e81ffa69a6726878a96529e5522e82
Reviewed-on: https://go-review.googlesource.com/c/tools/+/218839
Run-TryBot: Robert Findley <rfindley@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Update the servertest package to support connecting to a jsonrpc2 server
using either TCP or io.Pipes. The latter is provided so that regtests
can more accurately mimic the current gopls execution mode, where gopls
is run as a sidecar and communicated with via a pipe.
Updates golang/go#36879
Change-Id: I0e14ed0e628333ba2cc7b088009f1887fcaa82a5
Reviewed-on: https://go-review.googlesource.com/c/tools/+/218777
Run-TryBot: Robert Findley <rfindley@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
We had a deadlock in cases where a request was cancelled (1) after being
written to the stream, but (2) before a response was received. This
resulted in the request ID being removed from the pending map while the
server has the request, after which point the server response would hang
in Conn.Run trying to send to a nil channel.
After fixing this nil send there was still a race: it was possible that
Conn.Run could get the pending request, and Conn.Call would select
ctx.Done before Conn.Run could send to the response channel, again
resulting in a blocking send. Fix this by adding a buffer to the
response channel.
The response channel management is also made less forgiving, because we
should be able to reason precisely about how many sends and receives
will occur:
+ Don't close the response channel after sending a response: there
should only be one recipient.
+ Don't delete the ID from pending map twice: it should only be cleaned
up by Conn.Call.
Cancellation tests in the lsprpc package are updated to exercise the
race conditions.
Fixesgolang/go#37159
Change-Id: Ie3207442ea910f79247b18d8647fd52f39fb15db
Reviewed-on: https://go-review.googlesource.com/c/tools/+/219126
Run-TryBot: Robert Findley <rfindley@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Add a new Forwarder type to the lsprpc package, which implements the
jsonrpc2.StreamServer interface. This will be used to establish some
parity in the implementation of shared and singleton gopls servers.
Much more testing is needed, as is handling for the many edge cases
around forwarding the LSP, but since this is functionally equivalent to
TCP forwarding (and the -remote flag was already broken), I went ahead
and used the Forwarder to replace the forward method in the serve
command. This means that we can now use the combination of -listen and
-remote to chain together gopls servers... not that there's any reason
to do this.
Also, wrap the new regression tests with a focus on expressiveness when
testing the happy path, as well as parameterizing them so that they can
be run against different client/server execution environments. This
started to be sizable enough to warrant moving them to a separate
regtest package. The lsprpc package tests will instead focus on unit
testing the client-server binding logic.
Updates golang/go#36879
Updates golang/go#34111
Change-Id: Ib98131a58aabc69299845d2ecefceccfc1199574
Reviewed-on: https://go-review.googlesource.com/c/tools/+/218698
Run-TryBot: Robert Findley <rfindley@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Previously, the process of instantiating and running the LSP server was
sharded across the lsp, protocol, and cmd packages, and this resulted in
some APIs that are hard to work with. For example, it's hard to guess
the difference between lsp.NewClientServer, lsp.NewServer,
protocol.NewServer (which returns a client), and protocol.NewClient
(which returns a server).
This change reorganizes Server instantiation as follows:
+ The lsp.Server is now purely an implementation of the protocol.Server
interface. It is no longer responsible for installing itself into the
jsonrpc2 Stream, nor for running itself.
+ A new package 'lsprpc' is added, to implement the logic of binding an
incoming connection to an LSP server session. This is put in a
separate package for lack of a clear home: it didn't really
philosophically belong in any of the lsp, cmd, or protocol packages.
We can perhaps move it to cmd in the future, but I'd like to keep it
as a separate package while I develop request forwarding.
simplified import graph:
jsonrpc2 ⭠ lsprpc ⭠ cmd
⭩ ⭦
lsp (t.b.d. client tests)
⭩ ⭨
protocol source
+ The jsonrpc2 package is extended to have a minimal API for running a
'StreamServer': something analogous to an HTTP server that listens
for new connections and delegates to a handler (but we couldn't use
the word 'Handler' for this delegate as it was already taken).
After these changes, I hope that the concerns of "serving the LSP",
"serving jsonrpc2", and "installing the LSP on jsonrpc2" are more
logically organized, though one legitimate criticism is that the word
'Server' is still heavily overloaded.
This change prepares a subsequent change which hijacks the jsonrpc2
connection when forwarding messages to a shared gopls instance.
To test this change, the following improvements are made:
+ A servertest package is added to make it easier to run a test against
an in-process jsonrpc2 server. For now, this uses TCP but it could
easily be modified to use io.Pipe.
+ cmd tests are updated to use the servertest package. Unfortunately it
wasn't yet possible to eliminate the concept of `remote=internal` in
favor of just using multiple sessions, because view initialization
involves calling both `go env` and `packages.Load`, which slow down
session startup significantly. See also golang.org/issue/35968.
Instead, the syntax for `-remote=internal` is modified to be
`-remote=internal@127.0.0.1:12345`.
+ An additional test for request cancellation is added for the
sessionserver package. This test uncovered a bug: when calling
Canceller.Cancel, we were using id rather than &id, which resulted in
incorrect json serialization (as only the pointer receiver implements
the json.Marshaller interface).
Updates golang/go#34111
Change-Id: I75c219df634348cdf53a9e57839b98588311a9ef
Reviewed-on: https://go-review.googlesource.com/c/tools/+/215742
Run-TryBot: Robert Findley <rfindley@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rebecca Stambler <rstambler@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>