Check client / agent versions over RPC #353
There are no files selected for viewing
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
|
|
@@ -165,6 +165,7 @@ linters: | |
| - Formatter | ||
| - gpio | ||
| - port | ||
| - Interceptor | ||
|
|
||
| lll: | ||
| line-length: 140 | ||
|
|
||
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
|
Member
There was a problem hiding this comment. Let's do not touch how the version is backed into the code in this PR. Please just take const |
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
|
Member
There was a problem hiding this comment. Let's do not touch how the version is backed into the code in this PR. Please just take const |
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
|
Member
There was a problem hiding this comment. I'd move this code to |
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,139 @@ | ||
| // Copyright 2025 Blindspot Software | ||
| // Use of this source code is governed by a BSD-style | ||
| // license that can be found in the LICENSE file. | ||
|
|
||
| package versioncheck | ||
|
|
||
| import ( | ||
| "context" | ||
| "errors" | ||
| "fmt" | ||
| "net/http" | ||
| "sync" | ||
|
|
||
| "connectrpc.com/connect" | ||
| ) | ||
|
|
||
| // NewServerInterceptor returns a connect interceptor that stamps the agent's | ||
| // version onto the response header of every RPC (unary and streaming), so | ||
| // clients always learn which agent build served them. | ||
| func NewServerInterceptor(version string) connect.Interceptor { | ||
| return &serverInterceptor{version: version} | ||
| } | ||
|
Comment on lines
+20
to
+22
Member
There was a problem hiding this comment. Is the constructor needed, or can we use defaults when struct fields are unset? Either way, empty strings need to be handled. Where is the advantage of a constructor? |
||
|
|
||
| type serverInterceptor struct { | ||
| version string | ||
| } | ||
|
|
||
| func (i *serverInterceptor) WrapUnary(next connect.UnaryFunc) connect.UnaryFunc { | ||
| return func(ctx context.Context, req connect.AnyRequest) (connect.AnyResponse, error) { | ||
| res, err := next(ctx, req) | ||
| if res != nil { | ||
| res.Header().Set(HeaderName, i.version) | ||
| } | ||
|
|
||
| return res, err | ||
| } | ||
| } | ||
|
|
||
| func (i *serverInterceptor) WrapStreamingClient(next connect.StreamingClientFunc) connect.StreamingClientFunc { | ||
| return next | ||
| } | ||
|
|
||
| func (i *serverInterceptor) WrapStreamingHandler(next connect.StreamingHandlerFunc) connect.StreamingHandlerFunc { | ||
| return func(ctx context.Context, conn connect.StreamingHandlerConn) error { | ||
| conn.ResponseHeader().Set(HeaderName, i.version) | ||
|
|
||
| return next(ctx, conn) | ||
| } | ||
| } | ||
|
|
||
| // NewClientInterceptor returns a connect interceptor that compares the agent | ||
| // version advertised on each response (via HeaderName) against self. On a Warn | ||
| // it calls onWarn once per connection; on an Error it fails the call with a | ||
| // FailedPrecondition error. onWarn may be nil. | ||
| func NewClientInterceptor(self string, onWarn, onInfo func(string)) connect.Interceptor { | ||
| return &clientInterceptor{self: self, onWarn: onWarn, onInfo: onInfo} | ||
| } | ||
|
|
||
| type clientInterceptor struct { | ||
| self string | ||
|
Member
There was a problem hiding this comment. Be consistent with the names of the version strings ("version" vs. "self") |
||
| onWarn func(string) | ||
| onInfo func(string) | ||
|
|
||
| once sync.Once | ||
| result error | ||
| } | ||
|
|
||
| // check classifies the peer version carried in header. It reports the observed | ||
| // version (onInfo) and any warning (onWarn) at most once per client, and returns | ||
| // — on every call — the cached error when the pairing is incompatible. | ||
| func (i *clientInterceptor) check(header http.Header) error { | ||
| i.once.Do(func() { | ||
| peer := header.Get(HeaderName) | ||
|
|
||
| if i.onInfo != nil { | ||
| i.onInfo(fmt.Sprintf("dutagent version: %s", peer)) | ||
| } | ||
|
|
||
| act, reason := classify(i.self, peer) | ||
| switch act { | ||
| case actionError: | ||
| i.result = connect.NewError(connect.CodeFailedPrecondition, errors.New(reason)) | ||
| case actionWarn: | ||
| if i.onWarn != nil && reason != "" { | ||
| i.onWarn(reason) | ||
| } | ||
| case actionOK: | ||
| } | ||
| }) | ||
|
|
||
| return i.result | ||
| } | ||
|
|
||
| func (i *clientInterceptor) WrapUnary(next connect.UnaryFunc) connect.UnaryFunc { | ||
| return func(ctx context.Context, req connect.AnyRequest) (connect.AnyResponse, error) { | ||
| res, err := next(ctx, req) | ||
| if err != nil { | ||
| return res, err | ||
| } | ||
|
|
||
| cerr := i.check(res.Header()) | ||
| if cerr != nil { | ||
| return nil, cerr | ||
| } | ||
|
|
||
| return res, nil | ||
| } | ||
| } | ||
|
|
||
| func (i *clientInterceptor) WrapStreamingHandler(next connect.StreamingHandlerFunc) connect.StreamingHandlerFunc { | ||
| return next | ||
| } | ||
|
|
||
| func (i *clientInterceptor) WrapStreamingClient(next connect.StreamingClientFunc) connect.StreamingClientFunc { | ||
| return func(ctx context.Context, spec connect.Spec) connect.StreamingClientConn { | ||
| return &checkingClientConn{ | ||
| StreamingClientConn: next(ctx, spec), | ||
| interceptor: i, | ||
| } | ||
| } | ||
| } | ||
|
|
||
| // checkingClientConn runs the version check after the first response is received | ||
| // (which is when the response header becomes available). The interceptor's own | ||
| // once guard makes the repeated calls cheap. | ||
| type checkingClientConn struct { | ||
| connect.StreamingClientConn | ||
|
|
||
| interceptor *clientInterceptor | ||
| } | ||
|
|
||
| func (c *checkingClientConn) Receive(msg any) error { | ||
| err := c.StreamingClientConn.Receive(msg) | ||
| if err != nil { | ||
| return err | ||
| } | ||
|
|
||
| return c.interceptor.check(c.ResponseHeader()) | ||
| } | ||
Oops, something went wrong.
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
Let's do not touch how the version is backed into the code in this PR. Please just take const
internal/buildinfo.Versionas given.