Add file server filter by ravenblackx · Pull Request #43243 · envoyproxy/envoy

ravenblackx · 2026-01-30T23:28:20Z

Commit Message: Add file server filter
Additional Description: Filter facilitates asynchronous serving from files. Simplistic configuration for the common use-case. Further features (e.g. exclusions) can be added later as needed. Secured against path-escapes by using std::filesystem::path to verify that the path requested isn't altered by normalization, and that it's within a path explicitly configured to be shared.
Risk Level: Negligible, as no change to existing operations, it's a new filter. It's marked work in progress and not assured secure, so should not be adopted at this time without due caution.
Testing: I think there's 100% coverage, but CI isn't running right now.
Docs Changes: New docs for it.
Release Notes: Will add at the end, to minimize annoying merge conflicts.
Platform Specific Features: Windows not supported, as AsyncFile operations don't currently support Windows.

Signed-off-by: Raven Black <ravenblack@dropbox.com>

repokitteh-read-only · 2026-01-30T23:28:25Z

As a reminder, PRs marked as draft will not be automatically assigned reviewers,
or be handled by maintainer-oncall triage.

Please mark your PR as ready when you want it to be reviewed!

🐱

Caused by: #43243 was opened by ravenblackx.

see: more, trace.

ravenblackx · 2026-01-30T23:28:27Z

/coverage

repokitteh-read-only · 2026-01-30T23:28:32Z

Coverage for this Pull Request will be rendered here:

https://storage.googleapis.com/envoy-cncf-pr/43243/coverage/index.html

For comparison, current coverage on main branch is here:

https://storage.googleapis.com/envoy-cncf-postsubmit/main/coverage/index.html

The coverage results are (re-)rendered each time the CI Envoy/Checks (coverage) job completes.

🐱

Caused by: a #43243 (comment) was created by @ravenblackx.

see: more, trace.

Signed-off-by: Raven Black <ravenblack@dropbox.com>

repokitteh-read-only · 2026-02-02T19:25:03Z

CC @envoyproxy/api-shepherds: Your approval is needed for changes made to (api/envoy/|docs/root/api-docs/).
envoyproxy/api-shepherds assignee is @wbpcode
CC @envoyproxy/api-watchers: FYI only for changes made to (api/envoy/|docs/root/api-docs/).
CC @envoyproxy/dependency-shepherds: Your approval is needed for changes made to (bazel/.*repos.*\.bzl)|(bazel/dependency_imports\.bzl)|(api/bazel/.*\.bzl)|(.*/requirements\.txt)|(.*\.patch).
envoyproxy/dependency-shepherds assignee is @jwendell

🐱

Caused by: #43243 was ready_for_review by ravenblackx.

see: more, trace.

Signed-off-by: Raven Black <ravenblack@dropbox.com>

…yproxy#43265 Signed-off-by: Raven Black <ravenblack@dropbox.com>

wbpcode

Thanks for this great contribution. Some initial comments to API.

wbpcode · 2026-02-03T01:18:11Z

/wait

Signed-off-by: Raven Black <ravenblack@dropbox.com>

jwendell

deps LGTM

Signed-off-by: Raven Black <ravenblack@dropbox.com>

ravenblackx · 2026-02-10T21:19:34Z

/retest

Signed-off-by: Raven Black <ravenblack@dropbox.com>

jwendell · 2026-02-12T13:05:21Z

/lgtm deps

wbpcode · 2026-02-22T13:22:01Z

happy to be listed as a codeowner - but as you say @wbpcode c++ is not my area - so would be great if you are up for also sponsoring

Yeah. I can also sponsor this new extension and @ravenblackx could add me to the codeowner list.

wbpcode

LGTM overall except some comments. The file_streamer is a little hard to follow but I also didn't get a better way.

/wait

wbpcode · 2026-02-22T13:25:28Z

+    // [#not-implemented-hide:] Directory operations currently have no async implementation.
+    message List {
+    }


nit: as a fresh new extension, I think any field that not implemented could be removed first because:

We may find no one want it in the future.

We may have a better API design in the future.

We want it - the catch is just that it requires implementing async directory operations first which is going to be additional PRs that I didn't want to roll up into this already large PR.

And I wanted the API review before going for that implementation. :)

wbpcode · 2026-02-22T13:46:37Z

+  createRouteSpecificFilterConfigTyped(const ProtoFileServerConfig& config,
+                                       Server::Configuration::ServerFactoryContext& context,
+                                       ProtobufMessage::ValidationVisitor& validator) override;


nit: it would be great if we can also add the createFilterFactoryFromProtoWithServerContext support here.

I don't understand what that function is for. How does it differ from createFilterFactoryFromProtoTyped? It has the same arguments except for dropping DualInfo, and it loses the StatusOr error path of the return value, so I assume it has to use exceptions instead.

This comment

// This method is for dual filter to create filter from server context when it is configured // in downstream. It won't be called if a dual filter is in upstream.

is not enlightening to me at all, as that seems to describe half of what createFilterFactoryFromProtoTyped is already doing. I don't understand why the default behavior is to throw an exception rather than just calling the other function that has to be overridden (or why it exists at all, given the name implies it exists to be the same as the other function but with ServerContext, but the other function already takes the same arguments).

createFilterFactoryFromProtoWithServerContext makes us could configure a filter in the route rather then downstream or upstream filter chain. At the route, we only have the server context and even have no DualInfo.

All these are historical technical debt. If even you, a maintainer, are confused about this, I think we do need a completely refactor to these methods.

Agree. I also have seen many configs using the DualInfo version, but haven't seen any actually consuming the DualInfo. So I would think a good option would be to have a default for each of the functions, that just calls createFilterFactoryFromProtoWithServerContext (the lowest common denominator of available arguments), and then only override that one for the common case.

Except that createFilterFactoryFromProtoWithServerContext doesn't return a status. :(

Signed-off-by: Raven Black <ravenblack@dropbox.com>

ravenblackx · 2026-02-23T20:00:31Z

/retest

Signed-off-by: Raven Black <ravenblack@dropbox.com>

ravenblackx · 2026-02-24T19:00:02Z

Found what the fuzz test problem is, it's nothing to do with my filter, it's that the fuzz tester picks a "random" filter if there's no config, and adding one more filter changes the outcome of that randomness to a filter that crashes.

ravenblackx · 2026-02-24T21:07:52Z

#43627 to address the caused-but-unrelated test breakage.

wbpcode

LGTM. Thanks.

Signed-off-by: Raven Black <ravenblack@dropbox.com>

Commit Message: Add file server filter Additional Description: Filter facilitates asynchronous serving from files. Simplistic configuration for the common use-case. Further features (e.g. exclusions) can be added later as needed. Secured against path-escapes by using `std::filesystem::path` to verify that the path requested isn't altered by normalization, and that it's within a path explicitly configured to be shared. Risk Level: Negligible, as no change to existing operations, it's a new filter. It's marked work in progress and not assured secure, so should not be adopted at this time without due caution. Testing: I think there's 100% coverage, but CI isn't running right now. Docs Changes: New docs for it. Release Notes: Will add at the end, to minimize annoying merge conflicts. Platform Specific Features: Windows not supported, as AsyncFile operations don't currently support Windows. --------- Signed-off-by: Raven Black <ravenblack@dropbox.com> Signed-off-by: bjmask <11672696+bjmask@users.noreply.github.com>

Commit Message: Add file server filter Additional Description: Filter facilitates asynchronous serving from files. Simplistic configuration for the common use-case. Further features (e.g. exclusions) can be added later as needed. Secured against path-escapes by using `std::filesystem::path` to verify that the path requested isn't altered by normalization, and that it's within a path explicitly configured to be shared. Risk Level: Negligible, as no change to existing operations, it's a new filter. It's marked work in progress and not assured secure, so should not be adopted at this time without due caution. Testing: I think there's 100% coverage, but CI isn't running right now. Docs Changes: New docs for it. Release Notes: Will add at the end, to minimize annoying merge conflicts. Platform Specific Features: Windows not supported, as AsyncFile operations don't currently support Windows. --------- Signed-off-by: Raven Black <ravenblack@dropbox.com>

Add file server filter

9d578d6

Signed-off-by: Raven Black <ravenblack@dropbox.com>

ravenblackx added 3 commits February 2, 2026 17:08

Improve coverage, fix docgen

36edcd2

Signed-off-by: Raven Black <ravenblack@dropbox.com>

Accommodate rename of com_github_cncf_xds

ff9ba4f

Signed-off-by: Raven Black <ravenblack@dropbox.com>

Merge branch 'main' into file_server

2b32c67

Signed-off-by: Raven Black <ravenblack@dropbox.com>

ravenblackx marked this pull request as ready for review February 2, 2026 19:24

repokitteh-read-only Bot added api deps Approval required for changes to Envoy's external dependencies labels Feb 2, 2026

repokitteh-read-only Bot assigned wbpcode and jwendell Feb 2, 2026

ravenblackx added 4 commits February 2, 2026 20:10

Move abslStatusToHttpStatus into its own library, and add coverage

ff97678

Signed-off-by: Raven Black <ravenblack@dropbox.com>

Add one more line of test coverage!

f46d7dd

Signed-off-by: Raven Black <ravenblack@dropbox.com>

Remove unused usings

908bee7

Signed-off-by: Raven Black <ravenblack@dropbox.com>

Remove deps that are inherited anyway, to avoid conflicting with envo…

16c41f0

…yproxy#43265 Signed-off-by: Raven Black <ravenblack@dropbox.com>

wbpcode reviewed Feb 3, 2026

View reviewed changes

Comment thread api/envoy/extensions/filters/http/file_server/v3/file_server.proto Outdated

Comment thread api/envoy/extensions/filters/http/file_server/v3/file_server.proto

repokitteh-read-only Bot added the waiting label Feb 3, 2026

try_file->default_file, directory_list->list, drop oneof

d0749b1

Signed-off-by: Raven Black <ravenblack@dropbox.com>

repokitteh-read-only Bot removed the waiting label Feb 3, 2026

ravenblackx added 4 commits February 3, 2026 17:34

Add virtual destructor to FileStreamerClient

edbbdba

Signed-off-by: Raven Black <ravenblack@dropbox.com>

DirectoryList->List too

9b9b443

Signed-off-by: Raven Black <ravenblack@dropbox.com>

Format

0da1383

Signed-off-by: Raven Black <ravenblack@dropbox.com>

Double backticks

006ed2d

Signed-off-by: Raven Black <ravenblack@dropbox.com>

jwendell previously approved these changes Feb 4, 2026

View reviewed changes

repokitteh-read-only Bot removed the deps Approval required for changes to Envoy's external dependencies label Feb 4, 2026

wbpcode reviewed Feb 5, 2026

View reviewed changes

Comment thread api/envoy/extensions/filters/http/file_server/v3/file_server.proto

repokitteh-read-only Bot added the waiting:any label Feb 5, 2026

Hide the unused message type from docgen

fa7ea2a

Signed-off-by: Raven Black <ravenblack@dropbox.com>

ravenblackx requested a review from wbpcode February 10, 2026 21:20

Merge branch 'main' into file_server

e59c932

Signed-off-by: Raven Black <ravenblack@dropbox.com>

repokitteh-read-only Bot added the deps Approval required for changes to Envoy's external dependencies label Feb 10, 2026

repokitteh-read-only Bot removed the deps Approval required for changes to Envoy's external dependencies label Feb 12, 2026

wbpcode reviewed Feb 22, 2026

View reviewed changes

repokitteh-read-only Bot added the waiting label Feb 22, 2026

Address comments

f80dfe8

Signed-off-by: Raven Black <ravenblack@dropbox.com>

repokitteh-read-only Bot removed the waiting label Feb 23, 2026

ravenblackx added 2 commits February 23, 2026 17:10

Add wbpcode as CODEOWNER

d2ef56c

Signed-off-by: Raven Black <ravenblack@dropbox.com>

Make manager_config mandatory

5cb575b

Signed-off-by: Raven Black <ravenblack@dropbox.com>

ravenblackx requested a review from wbpcode February 23, 2026 17:25

ravenblackx added 4 commits February 23, 2026 20:48

Fuzz tester limitation

66e9e62

Signed-off-by: Raven Black <ravenblack@dropbox.com>

Ensure config destruction happens in the same thread

834c57a

Signed-off-by: Raven Black <ravenblack@dropbox.com>

The right delete!

eed2662

Signed-off-by: Raven Black <ravenblack@dropbox.com>

Merge branch 'main' into file_server

2ec9d35

Signed-off-by: Raven Black <ravenblack@dropbox.com>

wbpcode approved these changes Feb 25, 2026

View reviewed changes

repokitteh-read-only Bot removed the api label Feb 25, 2026

Merge branch 'main' into file_server

2da03e3

Signed-off-by: Raven Black <ravenblack@dropbox.com>

ravenblackx merged commit 506746a into envoyproxy:main Feb 26, 2026
30 checks passed

Conversation

ravenblackx commented Jan 30, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

repokitteh-read-only Bot commented Jan 30, 2026

Uh oh!

ravenblackx commented Jan 30, 2026

Uh oh!

repokitteh-read-only Bot commented Jan 30, 2026

Uh oh!

repokitteh-read-only Bot commented Feb 2, 2026

Uh oh!

wbpcode left a comment

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Uh oh!

wbpcode commented Feb 3, 2026

Uh oh!

jwendell left a comment

Choose a reason for hiding this comment

Uh oh!

Uh oh!

ravenblackx commented Feb 10, 2026

Uh oh!

jwendell commented Feb 12, 2026

Uh oh!

wbpcode commented Feb 22, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

wbpcode left a comment

Choose a reason for hiding this comment

Uh oh!

wbpcode Feb 22, 2026

Choose a reason for hiding this comment

Uh oh!

ravenblackx Feb 23, 2026

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

wbpcode Feb 22, 2026

Choose a reason for hiding this comment

Uh oh!

ravenblackx Feb 23, 2026

Choose a reason for hiding this comment

Uh oh!

wbpcode Feb 25, 2026

Choose a reason for hiding this comment

Uh oh!

ravenblackx Feb 26, 2026

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

ravenblackx commented Feb 23, 2026

Uh oh!

ravenblackx commented Feb 24, 2026

Uh oh!

ravenblackx commented Feb 24, 2026

Uh oh!

wbpcode left a comment

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

5 participants

ravenblackx commented Jan 30, 2026 •

edited

Loading

wbpcode commented Feb 22, 2026 •

edited

Loading