feat: dummy sync server (#53)

Signed-off-by: Todd Baert <[email protected]>
Co-authored-by: Kavindu Dodanduwa <[email protected]>

.github/workflows/ci.yml

@@ -12,6 +12,9 @@ on:
 permissions:
   contents: read
 
+env:
+  GO_VERSION: 1.19.3
+
 jobs:
   build:
     runs-on: ubuntu-latest
@@ -27,7 +30,16 @@ jobs:
       - name: Lint Gherkin
         run: npm run gherkin-lint
 
-      - name: Build Docker image
+      - name: Build flagd-testbed Docker image
+        uses: docker/build-push-action@v4
+        with:
+          context: .
+          file: flagd/Dockerfile
+          push: false
+
+      - name: Build sync-testbed Docker image
         uses: docker/build-push-action@v4
         with:
+          context: .
+          file: sync/Dockerfile
           push: false

.github/workflows/release-please.yml

@@ -10,7 +10,9 @@ permissions:
 
 env:
   REGISTRY: ghcr.io
-  IMAGE_NAME: flagd-testbed
+  FLAGD_IMAGE_NAME: flagd-testbed
+  SYNC_IMAGE_NAME: sync-testbed
+  GO_VERSION: 1.19.3
 
 jobs:
   release-please:
@@ -50,10 +52,22 @@ jobs:
           username: ${{ github.actor }}
           password: ${{ secrets.GITHUB_TOKEN }}
 
-      - name: Build and push Docker image
+      - name: Build and push flagd-testbed Docker image
         uses: docker/build-push-action@v4
         with:
+          context: .
+          file: flagd/Dockerfile
           push: true
           tags: |
-            ${{ env.REGISTRY }}/open-feature/${{ env.IMAGE_NAME }}:${{ needs.release-please.outputs.release_tag_name }}
-            ${{ env.REGISTRY }}/open-feature/${{ env.IMAGE_NAME }}:latest
+            ${{ env.REGISTRY }}/open-feature/${{ env.FLAGD_IMAGE_NAME }}:${{ needs.release-please.outputs.release_tag_name }}
+            ${{ env.REGISTRY }}/open-feature/${{ env.FLAGD_IMAGE_NAME }}:latest
+
+      - name: Build and push sync-testbed Docker image
+        uses: docker/build-push-action@v4
+        with:
+          context: .
+          file: sync/Dockerfile
+          push: true
+          tags: |
+            ${{ env.REGISTRY }}/open-feature/${{ env.SYNC_IMAGE_NAME }}:${{ needs.release-please.outputs.release_tag_name }}
+            ${{ env.REGISTRY }}/open-feature/${{ env.SYNC_IMAGE_NAME }}:latest

.gitignore

@@ -1,3 +1,4 @@
 .idea
 node_modules
-flags/changing-flag.json
+flags/changing-flag.json
+bin/

Makefile

@@ -0,0 +1,6 @@
+.PHONY: clean
+clean:
+	rm -R bin/
+.PHONY: build-sync
+build-sync:
+	cd sync && go build -o ./bin/sync

README.md

@@ -6,4 +6,13 @@ This repository contains a docker image to support the [gherkin suites](https://
 
 The _flagd-testbed_ container is a docker image built on flagd, which essentially just adds a simple set of flags for the purposes of testing OpenFeature SDKs.
 `testing-flags.json` contains a set of flags consistent with the [evaluation feature](https://github.com/open-feature/spec/blob/main/specification/assets/gherkin/evaluation.feature).
-`change-flag.sh` runs in the test container generates a file `changing-flag.json`, which contains a flag that changes once every seconds, allowing to easily test change events.
+`change-flag.sh` runs in the test container generates a file `changing-flag.json`, which contains a flag that changes once every seconds, allowing to easily test change events.
+
+See the [flagd docs](https://flagd.dev/) for more information on flagd.
+
+## sync-testbed container
+
+The _sync_-testbed_ container is a docker image built on conforming to the sync.proto - a grpc which flagd or flagd in-process providers can use as a sync-source.
+It features an identical set of flags to the [flagd-testbed container](#flagd-testbed-container)
+
+For details on the sync-testbed, see [sync/README.me](sync/README.md)

Dockerfile → flagd/Dockerfile

@@ -4,7 +4,7 @@ FROM busybox:1.36
 
 COPY --from=flagd /flagd-build /flagd
 COPY flags/* .
-COPY wrapper.sh .
+COPY scripts/* .
 LABEL org.opencontainers.image.source = "https://github.com/open-feature/test-harness"
 
-ENTRYPOINT ["sh", "wrapper.sh"]
+ENTRYPOINT ["sh", "wrapper.sh", "./flagd", "start", "-f", "file:testing-flags.json", "-f", "file:changing-flag.json"]

wrapper.sh → scripts/wrapper.sh

@@ -1,5 +1,5 @@
 #!/bin/sh
-# wrapper script to start change-flag.sh and flagd, and forward signals to the child process
+# wrapper script to start change-flag.sh and flagd/sync, and forward signals to the child process
 
 # handle SIGINTs and SIGTERMs so we can kill the container
 handle_term() { 
@@ -13,10 +13,10 @@ handle_int() {
 trap handle_term SIGTERM
 trap handle_int SIGINT
 
-# start change script and flagd
+# start change script and our server
 sh ./change-flag.sh &
-./flagd start -f 'file:testing-flags.json' -f 'file:changing-flag.json' &
+"$@" &
 
-# wait on flagd
+# wait on server
 child=$! 
 wait "$child"

sync/Dockerfile

@@ -0,0 +1,16 @@
+FROM golang:1.21-alpine AS builder
+
+WORKDIR /src
+
+COPY sync .
+RUN go mod download
+RUN go build -o sync
+
+FROM busybox:1.36
+
+COPY --from=builder /src/sync .
+COPY flags/* .
+COPY scripts/* .
+LABEL org.opencontainers.image.source = "https://github.com/open-feature/test-harness"
+
+ENTRYPOINT ["sh", "wrapper.sh", "./sync", "start", "-f", "testing-flags.json", "-f", "changing-flag.json"]

sync/README.md

@@ -0,0 +1,86 @@
+## Flagd GRPC sync provider
+
+A simple [flagd](https://github.com/open-feature/flagd) gRPC flag configuration sync source.
+
+This implementation confirms to gPRC sync definition of flagd - https://buf.build/open-feature/flagd/docs/main:sync.v1
+
+### How to run ?
+
+#### go run / binary
+
+```shell
+go run main.go start -f your-flags.json
+```
+
+and then, start flagd in local mode (for example with source):
+
+```shell
+go run main.go start -f your-flags.json --uri grpc://127.0.0.1:8080 --debug
+```
+
+#### Options
+
+Following options are available to the start command,
+
+```text
+  -f string
+       file to watch (can be specified more than once)
+  -certPath string
+        certificate path for tls connection
+  -h string
+        hostDefault of the server (default "0.0.0.0")
+  -keyPath string
+        certificate key for tls connection
+  -p string
+        portDefault of the server (default "9090")
+  -s    enable tls
+```
+
+For example, to start with TLS certs,
+
+```shell
+go run main.go -s=true -certPath=server.crt -keyPath=server.key
+```
+
+Then start your flagd with gRPC TLS sync.
+
+### Running RPCs from the command line
+
+Test the sync from the command line with [grpcurl](https://github.com/fullstorydev/grpcurl) (requires you have a copy of [sync.proto](https://raw.githubusercontent.com/open-feature/schemas/main/protobuf/sync/v1/sync_service.proto) at `/path/to/proto/dir/`):
+
+```shell
+# request all flags
+grpcurl -import-path '/path/to/proto/dir' -proto sync.proto -plaintext localhost:9090 sync.v1.FlagSyncService/FetchAllFlags
+```
+
+```shell
+# open a stream for getting flag changes
+grpcurl -import-path '/path/to/proto/dir' -proto sync.proto -plaintext localhost:9090 sync.v1.FlagSyncService/SyncFlags
+```
+
+### Generate certificates ? 
+
+Given below are some commands you can use to generate CA cert and Server cert to used with `localhost`
+
+#### Generate CA cert
+
+- CA Private Key: `openssl ecparam -name prime256v1 -genkey -noout -out ca.key`
+- CA Certificate: `openssl req -new -x509 -sha256 -key ca.key -out ca.cert`
+
+#### Generate Server certificate
+
+- Server private key:  `openssl ecparam -name prime256v1 -genkey -noout -out server.key`
+- Server signing request:  `openssl req -new -sha256 -addext "subjectAltName=DNS:localhost" -key server.key -out server.csr`
+- Server cert:  `openssl x509 -req -in server.csr -CA ca.cert -CAkey ca.key  -out server.crt -days 1000 -sha256 -extfile opnessl.conf`
+
+Where the file `opnessl.conf` contains following,
+
+`subjectAltName = DNS:localhost`
+
+#### Running grpc server with certificates
+
+`go run main.go -s=true -certPath=server.crt -keyPath=server.key`
+
+#### Running flagd with certificates
+
+`go run main.go start --sources='[{"uri":"grpcs://localhost:9090","provider":"grpc", "certPath":"ca.cert"}]'`

sync/go.mod

@@ -0,0 +1,35 @@
+module github.com/open-feature/test-harness/sync
+
+go 1.19
+
+require (
+	buf.build/gen/go/open-feature/flagd/grpc/go v1.3.0-20230822184021-85780df4e019.1
+	buf.build/gen/go/open-feature/flagd/protocolbuffers/go v1.31.0-20230822184021-85780df4e019.1
+	github.com/fsnotify/fsnotify v1.6.0
+	go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.43.0
+	go.opentelemetry.io/otel v1.17.0
+	go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.17.0
+	go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc v1.17.0
+	go.opentelemetry.io/otel/sdk v1.17.0
+	golang.org/x/exp v0.0.0-20230817173708-d852ddb80c63
+	google.golang.org/grpc v1.57.0
+)
+
+require (
+	cloud.google.com/go/compute v1.23.0 // indirect
+	github.com/cenkalti/backoff/v4 v4.2.1 // indirect
+	github.com/go-logr/logr v1.2.4 // indirect
+	github.com/go-logr/stdr v1.2.2 // indirect
+	github.com/golang/protobuf v1.5.3 // indirect
+	github.com/grpc-ecosystem/grpc-gateway/v2 v2.17.1 // indirect
+	go.opentelemetry.io/otel/metric v1.17.0 // indirect
+	go.opentelemetry.io/otel/trace v1.17.0 // indirect
+	go.opentelemetry.io/proto/otlp v1.0.0 // indirect
+	golang.org/x/net v0.14.0 // indirect
+	golang.org/x/sys v0.11.0 // indirect
+	golang.org/x/text v0.12.0 // indirect
+	google.golang.org/genproto v0.0.0-20230822172742-b8732ec3820d // indirect
+	google.golang.org/genproto/googleapis/api v0.0.0-20230822172742-b8732ec3820d // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20230822172742-b8732ec3820d // indirect
+	google.golang.org/protobuf v1.31.0 // indirect
+)