specs: add specs for api manager

Signed-off-by: Sonu Saha <ahasunos@gmail.com>

spec/fixtures/api_configuration.yml

@@ -0,0 +1,11 @@
+# spec/fixtures/api_configuration.yml
+base_url: https://api.example.com/
+apis:
+  endpoint1:
+    path: 'path/to/endpoint1'
+    description: 'Endpoint 1 description'
+    no_cache: true
+  endpoint2:
+    path: 'path/to/endpoint2'
+    description: 'Endpoint 2 description'
+    ttl: 600

spec/unit/api_manager_spec.rb

@@ -0,0 +1,69 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+require 'api_wrapper/api_manager'
+require 'api_wrapper/cache/cache_store'
+require 'api_wrapper/cache/cache_policy'
+
+RSpec.describe ApiWrapper::ApiManager do
+  let(:api_configuration_path) { 'spec/fixtures/api_configuration.yml' }
+  let(:cache_store) { ApiWrapper::Cache::CacheStore.new }
+  let(:api_manager) { described_class.new(api_configuration_path, cache_store: cache_store) }
+
+  describe '#initialize' do
+    it 'loads API configuration from file' do
+      expect(api_manager.endpoints).to include('endpoint1' => a_hash_including('path' => 'path/to/endpoint1'))
+      expect(api_manager.base_url).to eq('https://api.example.com/')
+    end
+
+    it 'configures cache policy based on YAML settings' do
+      cache_policy = api_manager.instance_variable_get(:@cache_policy)
+
+      # Check no-cache configuration
+      expect(cache_policy.use_cache?('path/to/endpoint1')).to be_falsey
+
+      # Check custom TTL configuration
+      expect(cache_policy.ttl_for('path/to/endpoint2')).to eq(600)
+    end
+  end
+
+  describe '#fetch_data' do
+    let(:endpoint_key) { 'endpoint2' }
+    let(:response_body) { { 'status' => 'success' }.to_json }
+
+    before do
+      stub_request(:get, 'https://api.example.com/path/to/endpoint2')
+        .to_return(status: 200, body: response_body, headers: {})
+    end
+
+    it 'fetches data from the API and caches it' do
+      response = api_manager.fetch_data(endpoint_key)
+      expect(JSON.parse(response.body)).to eq('status' => 'success')
+
+      # Verify that the data was cached
+      cached_data = cache_store.read('path/to/endpoint2')
+      expect(JSON.parse(cached_data)).to eq('status' => 'success')
+    end
+
+    it 'raises an error if the endpoint key is invalid' do
+      expect do
+        api_manager.fetch_data('invalid_endpoint')
+      end.to raise_error(ArgumentError, 'Invalid endpoint key: invalid_endpoint')
+    end
+
+    context 'when force_refresh is true' do
+      it 'bypasses the cache and fetches fresh data' do
+        # Pre-cache some data
+        cache_store.write('path/to/endpoint2', response_body, 300)
+
+        # Fetch fresh data
+        response = api_manager.fetch_data(endpoint_key, force_refresh: true)
+        expect(JSON.parse(response.body)).to eq('status' => 'success')
+
+        # Ensure the cache is updated with fresh data
+        cached_data = cache_store.read('path/to/endpoint2')
+        expect(JSON.parse(cached_data)).to eq('status' => 'success')
+      end
+    end
+  end
+end