Adding Simple Gin Unit Tests (#24)

Add a very basic gin test example where we
get the index page and check it contains
a particular post in the mock database.

To complete this, I had to mock the database
by turning the previous declaration into
an interface, and moving the concrete types
into `SqlDatabase`. The mock is done in `DatabaseMock`.

.github/workflows/pipeline.yml

@@ -13,9 +13,11 @@ jobs:
   build:
     uses: ./.github/workflows/build.yml
     needs: failfast
-  # tests:
-  #   uses: ./.github/workflows/test.yml
-  #   needs: build
+
+  tests:
+    uses: ./.github/workflows/test.yml
+    needs: build
+
   # release:
   #   uses: ./.github/workflows/release.yml
   #   needs: tests

.github/workflows/test.yml

@@ -0,0 +1,24 @@
+name: Tests
+
+on: [workflow_call]
+
+jobs:
+  linters:
+    name: Tests 🧪
+
+    runs-on: ubuntu-latest
+    container:
+      image: mattgomes28/urchin-golang:0.2
+      options: --user 1001
+
+    steps:
+    - uses: actions/checkout@v3
+
+    - name: Generating templ files
+      run: |
+        templ generate
+      shell: bash
+
+    - name: Running Go Tests 🧪
+      run: |
+        go test ./... -v

admin-app/app.go

@@ -2,7 +2,6 @@ package admin_app
 
 import (
 	"encoding/json"
-	"fmt"
 	"net/http"
 	"strconv"
 
@@ -33,7 +32,7 @@ type DeletePostRequest struct {
 	Id int `json:"id"`
 }
 
-func getPostHandler(database *database.Database) func(*gin.Context) {
+func getPostHandler(database database.Database) func(*gin.Context) {
 	return func(c *gin.Context) {
 		// localhost:8080/post/{id}
 		var post_binding PostBinding
@@ -73,7 +72,7 @@ func getPostHandler(database *database.Database) func(*gin.Context) {
 	}
 }
 
-func postPostHandler(database *database.Database) func(*gin.Context) {
+func postPostHandler(database database.Database) func(*gin.Context) {
 	return func(c *gin.Context) {
 		var add_post_request AddPostRequest
 		decoder := json.NewDecoder(c.Request.Body)
@@ -108,7 +107,7 @@ func postPostHandler(database *database.Database) func(*gin.Context) {
 	}
 }
 
-func putPostHandler(database *database.Database) func(*gin.Context) {
+func putPostHandler(database database.Database) func(*gin.Context) {
 	return func(c *gin.Context) {
 		var change_post_request ChangePostRequest
 		decoder := json.NewDecoder(c.Request.Body)
@@ -145,7 +144,7 @@ func putPostHandler(database *database.Database) func(*gin.Context) {
 	}
 }
 
-func deletePostHandler(database *database.Database) func(*gin.Context) {
+func deletePostHandler(database database.Database) func(*gin.Context) {
 	return func(c *gin.Context) {
 		var delete_post_request DeletePostRequest
 		decoder := json.NewDecoder(c.Request.Body)
@@ -177,21 +176,14 @@ func deletePostHandler(database *database.Database) func(*gin.Context) {
 	}
 }
 
-func Run(app_settings common.AppSettings, database database.Database) error {
+func SetupRoutes(app_settings common.AppSettings, database database.Database) *gin.Engine {
 
 	r := gin.Default()
 	r.MaxMultipartMemory = 1
 
-	r.GET("/posts/:id", getPostHandler(&database))
-	r.POST("/posts", postPostHandler(&database))
-	r.PUT("/posts", putPostHandler(&database))
-	r.DELETE("/posts", deletePostHandler(&database))
-
-	err := r.Run(fmt.Sprintf(":%s", app_settings.WebserverPort))
-	if err != nil {
-		log.Error().Msgf("could not run app: %v", err)
-		return err
-	}
-
-	return nil
+	r.GET("/posts/:id", getPostHandler(database))
+	r.POST("/posts", postPostHandler(database))
+	r.PUT("/posts", putPostHandler(database))
+	r.DELETE("/posts", deletePostHandler(database))
+	return r
 }

app/app.go

@@ -2,7 +2,6 @@ package app
 
 import (
 	"bytes"
-	"fmt"
 	"net/http"
 	"time"
 
@@ -15,9 +14,9 @@ import (
 
 const CACHE_TIMEOUT = 20 * time.Second
 
-type Generator = func(*gin.Context, common.AppSettings, *database.Database) ([]byte, error)
+type Generator = func(*gin.Context, common.AppSettings, database.Database) ([]byte, error)
 
-func Run(app_settings common.AppSettings, database *database.Database) error {
+func SetupRoutes(app_settings common.AppSettings, database database.Database) *gin.Engine {
 	r := gin.Default()
 	r.MaxMultipartMemory = 1
 
@@ -31,20 +30,14 @@ func Run(app_settings common.AppSettings, database *database.Database) error {
 	r.POST("/contact-send", makeContactFormHandler())
 
 	r.Static("/static", "./static")
-	err := r.Run(fmt.Sprintf(":%s", app_settings.WebserverPort))
-	if err != nil {
-		log.Error().Msgf("could not run app: %v", err)
-		return err
-	}
-
-	return nil
+	return r
 }
 
-func addCachableHandler(e *gin.Engine, method string, endpoint string, generator Generator, cache *Cache, app_settings common.AppSettings, db *database.Database) {
+func addCachableHandler(e *gin.Engine, method string, endpoint string, generator Generator, cache *Cache, app_settings common.AppSettings, db database.Database) {
 
 	handler := func(c *gin.Context) {
 		// if the endpoint is cached
-		cached_endpoint, err := cache.Get(c.Request.RequestURI)
+		cached_endpoint, err := (*cache).Get(c.Request.RequestURI)
 		if err == nil {
 			c.Data(http.StatusOK, "text/html; charset=utf-8", cached_endpoint.contents)
 			return
@@ -57,7 +50,7 @@ func addCachableHandler(e *gin.Engine, method string, endpoint string, generator
 		}
 
 		// After handler  (add to cache)
-		err = cache.Store(c.Request.RequestURI, html_buffer)
+		err = (*cache).Store(c.Request.RequestURI, html_buffer)
 		if err != nil {
 			log.Warn().Msgf("could not add page to cache: %v", err)
 		}
@@ -81,7 +74,7 @@ func addCachableHandler(e *gin.Engine, method string, endpoint string, generator
 
 // / This function will act as the handler for
 // / the home page
-func homeHandler(c *gin.Context, settings common.AppSettings, db *database.Database) ([]byte, error) {
+func homeHandler(c *gin.Context, settings common.AppSettings, db database.Database) ([]byte, error) {
 	posts, err := db.GetPosts()
 	if err != nil {
 		return nil, err

app/cache.go

@@ -22,55 +22,74 @@ func emptyEndpointCache() EndpointCache {
 	return EndpointCache{"", []byte{}, time.Now()}
 }
 
-type Cache struct {
+type Cache interface {
+	Get(name string) (EndpointCache, error)
+	Store(name string, buffer []byte) error
+	Size() uint64
+}
+
+type CacheValidator interface {
+	IsValid(cache *EndpointCache) bool
+}
+
+type TimeValidator struct{}
+
+func (validator *TimeValidator) IsValid(cache *EndpointCache) bool {
+	// We only return the cache if it's still valid
+	return cache.validUntil.After(time.Now())
+}
+
+type TimedCache struct {
 	cacheMap      shardedmap.ShardMap
 	cacheTimeout  time.Duration
 	estimatedSize atomic.Uint64 // in bytes
+	validator     CacheValidator
 }
 
-func (self *Cache) Store(name string, buffer []byte) error {
+func (cache *TimedCache) Store(name string, buffer []byte) error {
 	// Only store to the cache if we have enough space left
-	afterSizeMB := float64(self.estimatedSize.Load()+uint64(len(buffer))) / 1000000
+	afterSizeMB := float64(cache.estimatedSize.Load()+uint64(len(buffer))) / 1000000
 	if afterSizeMB > MAX_CACHE_SIZE_MB {
 		return fmt.Errorf("maximum size reached")
 	}
 
 	var cache_entry interface{} = EndpointCache{
 		name:       name,
 		contents:   buffer,
-		validUntil: time.Now().Add(self.cacheTimeout),
+		validUntil: time.Now().Add(cache.cacheTimeout),
 	}
-	self.cacheMap.Set(name, &cache_entry)
-	self.estimatedSize.Add(uint64(len(buffer)))
+	cache.cacheMap.Set(name, &cache_entry)
+	cache.estimatedSize.Add(uint64(len(buffer)))
 	return nil
 }
 
-func (self *Cache) Get(name string) (EndpointCache, error) {
+func (cache *TimedCache) Get(name string) (EndpointCache, error) {
 	// if the endpoint is cached
-	cached_entry := self.cacheMap.Get(name)
+	cached_entry := cache.cacheMap.Get(name)
 	if cached_entry != nil {
 		cache_contents := (*cached_entry).(EndpointCache)
 
 		// We only return the cache if it's still valid
-		if cache_contents.validUntil.After(time.Now()) {
+		if cache.validator.IsValid(&cache_contents) {
 			return cache_contents, nil
 		} else {
-			self.cacheMap.Delete(name)
+			cache.cacheMap.Delete(name)
 			return emptyEndpointCache(), fmt.Errorf("cached endpoint had expired")
 		}
 	}
 
 	return emptyEndpointCache(), fmt.Errorf("cache does not contain key")
 }
 
-func (self *Cache) Size() uint64 {
-	return self.estimatedSize.Load()
+func (cache *TimedCache) Size() uint64 {
+	return cache.estimatedSize.Load()
 }
 
 func makeCache(n_shards int, expiry_duration time.Duration) Cache {
-	return Cache{
+	return &TimedCache{
 		cacheMap:      shardedmap.NewShardMap(n_shards),
 		cacheTimeout:  expiry_duration,
 		estimatedSize: atomic.Uint64{},
+		validator:     &TimeValidator{},
 	}
 }

app/cache_test.go

@@ -0,0 +1,95 @@
+package app
+
+import (
+	"sync/atomic"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	shardedmap "github.com/zutto/shardedmap"
+)
+
+type TrueTimeMockValidator struct{}
+
+func (validator *TrueTimeMockValidator) IsValid(cache *EndpointCache) bool {
+	return true
+}
+
+type FalseTimeMockValidator struct{}
+
+func (validator *FalseTimeMockValidator) IsValid(cache *EndpointCache) bool {
+	return false
+}
+
+func makeTrueCacheMock() Cache {
+	return &TimedCache{
+		cacheMap:      shardedmap.NewShardMap(2),
+		cacheTimeout:  10 * time.Second,
+		estimatedSize: atomic.Uint64{},
+		validator:     &TrueTimeMockValidator{},
+	}
+}
+
+func makeFalseCacheMock() Cache {
+	return &TimedCache{
+		cacheMap:      shardedmap.NewShardMap(2),
+		cacheTimeout:  10 * time.Second,
+		estimatedSize: atomic.Uint64{},
+		validator:     &FalseTimeMockValidator{},
+	}
+}
+
+func TestCacheAddition(t *testing.T) {
+
+	test_data := []struct {
+		name     string
+		contents []byte
+	}{
+		{"first", []byte("hello")},
+		{"second", []byte("the quick brown fox does some weird stuff")},
+		{"veryLonNameThatIsProbablyTooLong", []byte("Hello there my friends")},
+		{"nPe9Rkff6ER6EzAxPUIpxc8UBBLm71hhq2MO9hkQWisrfihUqv", []byte("oA7Hv1A7vOuZSKrPT4ZN5DGKNSHZqpLEvUA5hu54CMyIt8c78u")},
+	}
+
+	cache := makeTrueCacheMock()
+
+	rolling_size := uint64(0)
+	for _, test_case := range test_data {
+
+		rolling_size += uint64(len(test_case.contents))
+		err := cache.Store(test_case.name, test_case.contents)
+		assert.Nil(t, err)
+		assert.Equal(t, cache.Size(), rolling_size)
+
+		endpoint_cache, err := cache.Get(test_case.name)
+		assert.Nil(t, err)
+		assert.Equal(t, endpoint_cache.contents, test_case.contents)
+	}
+}
+
+func TestCacheFailure(t *testing.T) {
+
+	test_data := []struct {
+		name     string
+		contents []byte
+	}{
+		{"first", []byte("hello")},
+		{"second", []byte("the quick brown fox does some weird stuff")},
+		{"veryLonNameThatIsProbablyTooLong", []byte("Hello there my friends")},
+		{"nPe9Rkff6ER6EzAxPUIpxc8UBBLm71hhq2MO9hkQWisrfihUqv", []byte("oA7Hv1A7vOuZSKrPT4ZN5DGKNSHZqpLEvUA5hu54CMyIt8c78u")},
+	}
+
+	cache := makeFalseCacheMock()
+
+	rolling_size := uint64(0)
+	for _, test_case := range test_data {
+
+		rolling_size += uint64(len(test_case.contents))
+		err := cache.Store(test_case.name, test_case.contents)
+		assert.Nil(t, err)
+		assert.Equal(t, cache.Size(), rolling_size)
+
+		_, err = cache.Get(test_case.name)
+		assert.NotNil(t, err)
+	}
+}

app/contact.go

@@ -58,7 +58,7 @@ func makeContactFormHandler() func(*gin.Context) {
 }
 
 // TODO : This is a duplicate of the index handler... abstract
-func contactHandler(c *gin.Context, app_settings common.AppSettings, db *database.Database) ([]byte, error) {
+func contactHandler(c *gin.Context, app_settings common.AppSettings, db database.Database) ([]byte, error) {
 	index_view := views.MakeContactPage()
 	html_buffer := bytes.NewBuffer(nil)
 	if err := index_view.Render(c, html_buffer); err != nil {

app/post.go

@@ -32,7 +32,7 @@ func mdToHTML(md []byte) []byte {
 	return markdown.Render(doc, renderer)
 }
 
-func postHandler(c *gin.Context, app_settings common.AppSettings, database *database.Database) ([]byte, error) {
+func postHandler(c *gin.Context, app_settings common.AppSettings, database database.Database) ([]byte, error) {
 	// localhost:8080/post/{id}
 
 	var post_binding PostBinding