Add configuration tests and documentation

Co-authored-by: coopernetes <57812123+coopernetes@users.noreply.github.com>

Author: Copilot

CONFIGURATION.md

@@ -0,0 +1,174 @@
+# Configuration Guide
+
+The Jetty-based GitProxy server supports configuration via YAML files. This allows you to configure providers, filters, and other server settings without modifying code.
+
+## Configuration Files
+
+The server loads configuration from the following files in order:
+1. `src/main/resources/application.yml` - Base configuration
+2. `src/main/resources/application-local.yml` - Local overrides (merged with base)
+
+Configuration from `application-local.yml` will override or extend settings from `application.yml`.
+
+## Server Configuration
+
+```yaml
+server:
+  port: 8080  # HTTP port for the server
+```
+
+## Provider Configuration
+
+Providers define the Git hosting services that the proxy will forward requests to.
+
+### Built-in Providers
+
+The following providers are built-in:
+- `github` - GitHub (https://github.com)
+- `gitlab` - GitLab (https://gitlab.com)
+- `bitbucket` - Bitbucket (https://bitbucket.org)
+
+### Example Provider Configuration
+
+```yaml
+git-proxy:
+  base-path: "/git"  # Optional base path for all servlets
+  providers:
+    github:
+      enabled: true
+    gitlab:
+      enabled: true
+      servlet-path: /custom-gitlab  # Optional custom path
+    bitbucket:
+      enabled: false
+    # Custom provider example
+    internal-github:
+      enabled: true
+      servlet-path: /enterprise-github
+      uri: https://githubserver.example.com
+```
+
+### Provider Options
+
+- `enabled` (boolean): Enable/disable the provider
+- `uri` (string): Custom URI for the provider (for self-hosted instances)
+- `servlet-path` (string): Custom servlet path (default is based on provider name)
+- `log-proxy` (boolean): Enable proxy logging (default: true)
+- `connect-timeout` (int): Connection timeout in milliseconds (default: -1, no timeout)
+- `read-timeout` (int): Read timeout in milliseconds (default: -1, no timeout)
+
+## Filter Configuration
+
+Filters control access to repositories and enforce policies.
+
+### GitHub User Authentication Filter
+
+Requires authentication for GitHub operations.
+
+```yaml
+git-proxy:
+  filters:
+    github-user-authenticated:
+      enabled: true
+      order: 1
+      operations:
+        - PUSH
+      required-auth-schemes: bearer, token, basic  # Can be comma-separated or list
+      providers:
+        - github
+```
+
+Options:
+- `enabled` (boolean): Enable/disable the filter
+- `order` (int): Filter execution order (lower numbers run first)
+- `operations` (list): Git operations to apply filter to (PUSH, FETCH)
+- `required-auth-schemes` (string or list): Required authentication schemes (bearer, token, basic)
+- `providers` (list): Provider names to apply filter to
+
+### Whitelist Filters
+
+Control which repositories can be accessed.
+
+```yaml
+git-proxy:
+  filters:
+    whitelists:
+      - enabled: true
+        order: 5
+        operations:
+          - FETCH
+          - PUSH
+        providers:
+          - github
+        slugs:
+          - coopernetes/test-repo
+          - finos/git-proxy
+      - enabled: true
+        order: 10
+        operations:
+          - PUSH
+        providers:
+          - gitlab
+        owners:
+          - finosfoundation
+      - enabled: true
+        order: 20
+        operations:
+          - FETCH
+        providers:
+          - github
+        names:
+          - hello-world
+```
+
+Options:
+- `enabled` (boolean): Enable/disable the filter
+- `order` (int): Filter execution order
+- `operations` (list): Git operations to apply filter to (PUSH, FETCH)
+- `providers` (list): Provider names to apply filter to
+- `slugs` (list): Repository slugs (owner/repo) to whitelist
+- `owners` (list): Repository owners to whitelist
+- `names` (list): Repository names to whitelist
+
+Note: You can use `slugs`, `owners`, and `names` together in a single whitelist entry, or separately for more granular control.
+
+## Running the Server
+
+```bash
+# Build the application
+./gradlew build
+
+# Run the application
+./gradlew run
+
+# Or run the JAR directly
+java -jar build/libs/jgit-proxy-*.jar
+```
+
+The server will read configuration from the YAML files and start with the configured providers and filters.
+
+## Example Usage
+
+Once the server is running, you can use it as a proxy for Git operations:
+
+```bash
+# Clone via proxy
+git clone http://localhost:8080/github.com/finos/git-proxy.git
+
+# Clone from GitLab via proxy
+git clone http://localhost:8080/gitlab.com/coopernetes/test-repo.git
+
+# Clone from custom provider
+git clone http://localhost:8080/debian/salsa/test-repo.git
+```
+
+## Logging
+
+The application uses SLF4J with Logback. You can configure logging levels in the YAML files:
+
+```yaml
+logging:
+  level:
+    org.finos.gitproxy: DEBUG
+    org.finos.gitproxy.git: DEBUG
+```

README.md

@@ -4,7 +4,53 @@ This is a simple implementation of a git proxy in Java. This is a possible succe
 ## Usage
 To use this project, you need to have Java 17 or higher installed on your machine. You can run the project using the following command:
 ```shell
-./gradlew bootRun
+./gradlew run
+```
+
+## Configuration
+
+The Jetty-based server supports YAML-based configuration for providers and filters. Configuration files:
+- `src/main/resources/application.yml` - Base configuration
+- `src/main/resources/application-local.yml` - Local overrides
+
+See [CONFIGURATION.md](CONFIGURATION.md) for detailed configuration options.
+
+### Quick Configuration Example
+
+Configure providers and filters in `application-local.yml`:
+
+```yaml
+server:
+  port: 8080
+
+git-proxy:
+  providers:
+    github:
+      enabled: true
+    gitlab:
+      enabled: true
+    bitbucket:
+      enabled: true
+  filters:
+    github-user-authenticated:
+      enabled: true
+      order: 1
+      operations:
+        - PUSH
+      required-auth-schemes: bearer, token, basic
+      providers:
+        - github
+    whitelists:
+      - enabled: true
+        order: 5
+        operations:
+          - FETCH
+          - PUSH
+        providers:
+          - github
+        slugs:
+          - coopernetes/test-repo
+          - finos/git-proxy
 ```
 
 ## Endpoints

src/test/java/org/finos/gitproxy/config/JettyConfigurationLoaderTest.java

@@ -0,0 +1,42 @@
+package org.finos.gitproxy.config;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+import java.util.List;
+import java.util.Map;
+import org.finos.gitproxy.provider.GitProxyProvider;
+import org.junit.jupiter.api.Test;
+
+class JettyConfigurationLoaderTest {
+
+    @Test
+    void testLoadDefaultConfiguration() {
+        JettyConfigurationLoader loader = new JettyConfigurationLoader();
+        assertNotNull(loader.getConfig());
+        assertNotNull(loader.getGitProxyConfig());
+    }
+
+    @Test
+    void testGetProviders() {
+        JettyConfigurationLoader loader = new JettyConfigurationLoader();
+        Map<String, Map<String, Object>> providers = loader.getProviders();
+        assertNotNull(providers);
+        assertTrue(providers.containsKey("github"));
+    }
+
+    @Test
+    void testGetServerPort() {
+        JettyConfigurationLoader loader = new JettyConfigurationLoader();
+        int port = loader.getServerPort();
+        assertEquals(8080, port);
+    }
+
+    @Test
+    void testBuildProviders() {
+        JettyConfigurationLoader loader = new JettyConfigurationLoader();
+        JettyConfigurationBuilder builder = new JettyConfigurationBuilder(loader);
+        List<GitProxyProvider> providers = builder.buildProviders();
+        assertNotNull(providers);
+        assertTrue(providers.size() >= 1); // At least github in test config
+    }
+}