Commit Graph
5 Commits
Author SHA1 Message Date
Brad FitzpatrickandBrad Fitzpatrick 82cfea90ca all: fix JSON serialization under Go 1.27's finalized encoding/json/v2
Go 1.27 enables GOEXPERIMENT=jsonv2 by default: encoding/json is now
backed by the json/v2 machinery, and github.com/go-json-experiment/json
compiles as a thin alias of the standard library's encoding/json/v2.
Several tag options and behaviors we relied on did not make the cut for
the final Go 1.27 API, breaking tailscaled at runtime and four packages'
tests. This change adapts to the final API while keeping the wire format
byte-for-byte identical on all Go versions.

First, the `format` tag option was demoted to experimental. Its mere
presence in a struct tag now makes marshaling and unmarshaling fail at
runtime. tailcfg.SSHAction.SessionDuration had `format:nano` (added in
a2dc517d7 to pin the v1 representation), so on Go 1.27 any netmap
containing an SSH policy failed to decode, breaking every PollNetMap.
Remove the option here and in net/speedtest; time.Duration still
marshals as int64 nanoseconds under encoding/json on all Go versions
(Go 1.27's v1 mode sets FormatDurationAsNano by default), so old
clients and servers are unaffected. Add a regression test locking in
the exact wire format.

Consequently, invert the cmd/vet jsontags rule: it previously required
an explicit `format` tag on time.Duration fields, which is now exactly
wrong. It now rejects any `format` tag option, which would have caught
this bug in CI.

Second, the `inline` tag option was renamed to `embed`. The standard
library silently ignores `inline`, while the pinned go-json-experiment
module (used on Go 1.26) only knows `inline`. Specify both options in
types/prefs and logtail; each implementation ignores the option it does
not know, producing identical output. Drop `inline` once we require
Go 1.27.

Third, encoding/json (v1) now dispatches to MarshalJSONTo and
UnmarshalJSONFrom methods and its v1 options flow into nested
jsonv2.MarshalEncode calls. Types whose v1 methods deliberately
routed through jsonv2 for v2 semantics (types/opt.Value, the
types/prefs preference types) would silently change wire format
(e.g. nil slices becoming null). Pin jsonv2.DefaultOptionsV2 in
their jsonv2 methods so the representation is the same regardless
of the entry point.

Finally, json.Marshal costs one more allocation under Go 1.27,
tripping the types/logger.AsJSON alloc test. Switch its fmt.Formatter
to jsonv2.MarshalWrite with explicit v1 options, which writes directly
to the fmt.State: one allocation on both toolchains with unchanged
output. Depaware files pick up the go-json-experiment/json/v1 options
shim as a new dependency of types/logger.

With this change, go test ./... passes with both Go 1.26.5 and
go1.27rc2.

Updates #20220
Fixes #20528
Fixes #20254

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Change-Id: I694c7d57fd81e55a579c579e9be10032bca569d4
2026-07-19 09:58:50 -07:00
James ScottandGitHub 94fbb03352 logtail: add stateless generic UploadLogs (#20005)
Add UploadLogs, a stateless alternative to NewLogger for callers that
want to push a batch of log entries without the background uploader,
ring buffer, stderr echoing, or network-up gating that a Logger
provides. Entries are encoded, batched up to the server's maximum
upload size, and POSTed synchronously; unlike Logger it does not retry.

The Logger construction is split into a new unexported newLogger so the
connection/encode/upload machinery is shared without starting the
background goroutine.

Log entries are modeled as a generic LogEntry[T] whose Value is inlined
(via go-json-experiment) alongside the reserved "logtail" metadata
member. T may be a struct (or pointer), a map with a string key, or a
jsontext.Value; use jsontext.Value to mix differently-shaped payloads in
a single upload. UploadLogs fills in client_time/proc_id/proc_seq from
the Config where the caller leaves them zero.

Updates tailscale/corp#40908

Change-Id: Idbf23cd0eb8233082fbdb9abed0f6f153b9225ba

Signed-off-by: James Scott <jim@tailscale.com>
2026-06-15 13:27:49 -07:00
Brad FitzpatrickandBrad Fitzpatrick 1fbb834dc3 logtail: add Logger.SetEnabled to toggle uploads at runtime
Callers that need to turn logtail uploads on and off in response to
user preference or policy changes previously had no choice: the
package-level Disable is a one-way kill switch intended for the
controlplane DisableLogTail debug message, and requires a process
restart to undo.

Add a per-Logger disabled flag, toggled via SetEnabled, that drops
incoming entries without buffering while disabled. The process-wide
Disable still takes precedence, so a controlplane-issued kill switch
cannot be overridden by a client setting it back on.

To simplify https://github.com/tailscale/tailscale-android/pull/695

Updates #13174

Change-Id: I06e75bd719c851f5f837ca5b2d1e17f7c68355f0
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2026-04-17 12:19:39 -07:00
Will NorrisandWill Norris 3ec5be3f51 all: remove AUTHORS file and references to it
This file was never truly necessary and has never actually been used in
the history of Tailscale's open source releases.

A Brief History of AUTHORS files
---

The AUTHORS file was a pattern developed at Google, originally for
Chromium, then adopted by Go and a bunch of other projects. The problem
was that Chromium originally had a copyright line only recognizing
Google as the copyright holder. Because Google (and most open source
projects) do not require copyright assignemnt for contributions, each
contributor maintains their copyright. Some large corporate contributors
then tried to add their own name to the copyright line in the LICENSE
file or in file headers. This quickly becomes unwieldy, and puts a
tremendous burden on anyone building on top of Chromium, since the
license requires that they keep all copyright lines intact.

The compromise was to create an AUTHORS file that would list all of the
copyright holders. The LICENSE file and source file headers would then
include that list by reference, listing the copyright holder as "The
Chromium Authors".

This also become cumbersome to simply keep the file up to date with a
high rate of new contributors. Plus it's not always obvious who the
copyright holder is. Sometimes it is the individual making the
contribution, but many times it may be their employer. There is no way
for the proejct maintainer to know.

Eventually, Google changed their policy to no longer recommend trying to
keep the AUTHORS file up to date proactively, and instead to only add to
it when requested: https://opensource.google/docs/releasing/authors.
They are also clear that:

> Adding contributors to the AUTHORS file is entirely within the
> project's discretion and has no implications for copyright ownership.

It was primarily added to appease a small number of large contributors
that insisted that they be recognized as copyright holders (which was
entirely their right to do). But it's not truly necessary, and not even
the most accurate way of identifying contributors and/or copyright
holders.

In practice, we've never added anyone to our AUTHORS file. It only lists
Tailscale, so it's not really serving any purpose. It also causes
confusion because Tailscalars put the "Tailscale Inc & AUTHORS" header
in other open source repos which don't actually have an AUTHORS file, so
it's ambiguous what that means.

Instead, we just acknowledge that the contributors to Tailscale (whoever
they are) are copyright holders for their individual contributions. We
also have the benefit of using the DCO (developercertificate.org) which
provides some additional certification of their right to make the
contribution.

The source file changes were purely mechanical with:

    git ls-files | xargs sed -i -e 's/\(Tailscale Inc &\) AUTHORS/\1 contributors/g'

Updates #cleanup

Change-Id: Ia101a4a3005adb9118051b3416f5a64a4a45987d
Signed-off-by: Will Norris <will@tailscale.com>
2026-01-23 15:49:45 -08:00
Brad FitzpatrickandBrad Fitzpatrick 11b770fbc9 feature/logtail: pull logtail + netlog out to modular features
Removes 434 KB from the minimal Linux binary, or ~3%.

Primarily this comes from not linking in the zstd encoding code.

Fixes #17323

Change-Id: I0a90de307dfa1ad7422db7aa8b1b46c782bfaaf7
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2025-09-29 08:33:04 -07:00