Add solution 3

Signed-off-by: Thomas Poignant <[email protected]>

testdata/flag-config.yaml

@@ -30,3 +30,21 @@ test-flag2:
   defaultRule:
     name: defaultRule
     variation: Default
+
+flagSets:
+  - name: set-team-1
+    flags:
+      test-flag2:
+        variations:
+          Default: false
+          False: false
+          True: true
+        targeting:
+          - name: rule1
+            query: key eq "not-a-key"
+            percentage:
+              False: 0
+              True: 100
+        defaultRule:
+          name: defaultRule
+          variation: Default

website/src/pages/specification/20241027-flagsets.md

@@ -8,7 +8,7 @@ Description: Flag sets are a way to group flags together.
 |                      |                                                   |
 |----------------------|---------------------------------------------------|
 | **Creation Date**    | 27/10/2024                                        |
-| **Last Update Date** | 27/10/2024                                        |
+| **Last Update Date** | 18/12/2024                                        |
 | **Authors**          | Thomas Poignant                                   |
 | **Status**           | ![draft](https://img.shields.io/badge/-draft-red) |
 
@@ -173,9 +173,85 @@ authorizedKeys:
 - If we want the same flag to be part of multiple flag sets, we need to duplicate the flag in multiple files.
 
 ### Solution 3
-:::note
-Feel free to propose other solutions here.
-:::
+In this solution we want to offer multiple way to specify the flag set in the configuration.  
+This solution will be more complex to implement, but it will give more flexibility to the users.
+
+In this solution the flag set could be defined:
+1. In the retriever configuration _(like in solution 2)_.
+2. And in the flag configuration file with a specific format.
+
+#### example: In the retriever configuration
+
+The relay proxy configuration will look like this:
+```yaml
+# ...
+retrievers:
+  - kind: file
+    path: config-file.goff.yaml
+    flagSet: flagset-teamA
+# ...
+```
+
+And the flag configuration file (`config-file.goff.yaml`) will look like this:
+```yaml
+# all the flags in this file will be part of the flag set flagset-teamA
+# ...
+test-flag:
+  variations:
+    enabled: true
+    disabled: false
+  defaultRule:
+    variation: enabled
+# ...
+```
+
+#### example: In the flag configuration file with a specific format
+
+In that case we don't need to specify the flag set in the retriever configuration.  
+The relay proxy configuration will look like this:
+```yaml
+# ...
+retrievers:
+  - kind: file
+    path: config-file.goff.yaml
+# ...
+```
+
+And the flag configuration file (`config-file.goff.yaml`) will look like this:
+```yaml
+# flagSets is a new key in the configuration file, that allow to create a super set with multiple flag sets.
+flagSets:
+  - name: flagset-teamA
+    flags:
+      test-flag2:
+        variations:
+          Default: false
+          False: false
+          True: true
+        targeting:
+          - name: rule1
+            query: key eq "not-a-key"
+            percentage:
+              False: 0
+              True: 100
+        defaultRule:
+          name: defaultRule
+          variation: Default
+  - name: flagset-teamB
+    flags:
+      test-flag2:
+        # ...
+```
+
+**PRO**
+- It gives flexibility in the way of creating the flag sets _(in the retriever or in the flag configuration file)_.
+- We can create multiple flag sets from a single retriver, by generating multiple flag sets in the flag configuration file.
+- We can still have multiple files for 1 flag set _(by specifying the same `flagSet` name in each file)_.
+- If we don't want to change the format of our configuration file, we can still set the flag sey in the retriever configuration.
+
+**CON**
+- If we configure a flag set name both in the retriever and in the flag configuration file, we need to decide which one to use _(most likely the one in the file)._
+- It is a bit more complex to implement than the other solutions.
 
 ## Decision