Add search functionality

database.go

@@ -4,12 +4,39 @@ import (
 	"io/fs"
 	"log"
 	"os"
+	"slices"
 	"strings"
+
+	"golang.org/x/text/search"
 )
 
 type Database struct {
 	Keys []string
 	Entries map[string]string
+	matcher *search.Matcher
+}
+
+func (db *Database) search(query string) []string { // returns keys (entry names)
+	results := []string{}
+	// compile patterns
+	queryPatterns := []*search.Pattern{}
+	for _, q := range strings.Split(query, " ") { // per word
+		queryPatterns = append(queryPatterns, db.matcher.CompileString(q))
+	}
+	// search
+	for _, k := range db.Keys {
+		patternsFound := 0
+		for _, p := range queryPatterns {
+			if s, _ := p.IndexString(db.Entries[k]); s != -1 {
+				patternsFound++ // this pattern was found
+			}
+		}
+		if patternsFound == len(queryPatterns) && !slices.Contains(results, k) {
+			// if all patterns were found, add the key (entry name) to the list
+			results = append(results, k)
+		}
+	}
+	return results
 }
 
 func BuildDB(directory string) Database {
@@ -19,14 +46,16 @@ func BuildDB(directory string) Database {
 	var keys []string
 	entries := map[string]string{}
 	// get files in directory and read them
-	directory = strings.TrimRight(directory, "/") // we don't need that last / -> if '/' is used as directory, you are dumb.
+	directory = strings.TrimRight(directory, "/") // we don't need that last /, don't use the root directory /
 	entriesDirFs := os.DirFS(directory)
 	keys, err := fs.Glob(entriesDirFs, "*")
 	if err != nil { logger.Panicln(err) }
 	for _, k := range keys {
 		contentB, err := os.ReadFile(directory + "/" + k)
 		if err != nil { logger.Panicln(err) }
-		entries[k] = string(contentB)
+		content := string(contentB)
+		entries[k] = content
 	}
-	return Database{Keys: keys, Entries: entries}
+	matcher := search.New(ContentLanguage, search.IgnoreCase, search.IgnoreDiacritics)
+	return Database{Keys: keys, Entries: entries, matcher: matcher}
 }

go.mod

@@ -1,3 +1,5 @@
 module github.com/ChaoticByte/plaintext-encyclopedia
 
 go 1.22.4
+
+require golang.org/x/text v0.17.0

go.sum

@@ -0,0 +1,2 @@
+golang.org/x/text v0.17.0 h1:XtiM5bkSOt+ewxlOE/aE/AKEHibwj/6gvWMl9Rsh0Qc=
+golang.org/x/text v0.17.0/go.mod h1:BuEKDfySbSR4drPmRPG/7iBdf8hvFMuRexcpahXilzY=

main.go

@@ -5,6 +5,7 @@ import (
 	"log"
 	"net/http"
 	"os"
+	"path"
 	"strings"
 )
 
@@ -28,16 +29,13 @@ func loadTemplate() {
 func handleApplication(w http.ResponseWriter, req *http.Request) {
 	var entry string
 	var err error
-	entryName := strings.Trim(req.URL.Path, "/")
+	entryName := path.Base(req.URL.Path)
-	if entryName != "" {
+	if entryName != "/" {
-		if strings.Contains(entryName, "/") || strings.Contains(entryName, "..") {
-			// path traversal
-			logger.Println("Possible path traversal attempt from", req.RemoteAddr, "to", entryName)
-			w.WriteHeader(http.StatusForbidden)
-			return
-		}
 		// load entry
 		entry = db.Entries[entryName]
+		if entry == "" { // redirect if entry doesn't exist (or is empty)
+			http.Redirect(w, req, "/", http.StatusTemporaryRedirect)
+		}
 	}
 	err = appTemplate.ExecuteTemplate(
 		w, "app",
@@ -45,6 +43,16 @@ func handleApplication(w http.ResponseWriter, req *http.Request) {
 	if err != nil { logger.Println(err) }
 }
 
+func handleSearchAPI(w http.ResponseWriter, req *http.Request) {
+	searchQuery := path.Base(req.URL.Path)
+	if searchQuery == "" {
+		w.WriteHeader(http.StatusBadRequest)
+		return
+	}
+	results := db.search(searchQuery)
+	w.Write([]byte(strings.Join(results, "\n")))
+}
+
 func main() {
 	// get logger
 	logger = log.Default()
@@ -57,6 +65,7 @@ func main() {
 	http.Handle("/static/", staticHandler)
 	// handle application
 	http.HandleFunc("/", handleApplication)
+	http.HandleFunc("/search/", handleSearchAPI)
 	// start server
 	logger.Println("Starting server on", ServerListen)
 	err := http.ListenAndServe(ServerListen, nil)

public/index.html

@@ -17,11 +17,16 @@
     </div>
 </div>
 {{- else -}}
-<div class="toc">
+<div class="home-main">
+    <input type="text" id="search-box" placeholder="search">
+    <div id="search-results" class="hidden"></div>
+    <div class="toc" id="toc">
     {{- range .TOC -}}
         <div><a href="{{ . }}">{{ . }}</a></div>
     {{- end -}}
     </div>
+</div>
+<script src="/static/search.js"></script>
 {{- end}}
 </body>
 </html>

public/static/search.js

@@ -0,0 +1,45 @@
+(() => {
+    let searchBox = document.getElementById("search-box");
+    let searchResults = document.getElementById("search-results");
+    let toc = document.getElementById("toc");
+
+    /**
+     * @param {string} results
+     */
+    function updateSearchResults(results) {
+        if (results.length > 0) {
+            searchResults.innerHTML = "";
+            for (let i = 0; i < results.length; i++) {
+                let resultElem = document.createElement("div");
+                let resultAnchor = document.createElement("a");
+                resultAnchor.href = results[i]; // we should be at /, so this is right
+                resultAnchor.innerText = results[i];
+                resultElem.appendChild(resultAnchor);
+                searchResults.appendChild(resultElem);
+            }
+            toc.classList.add("hidden");
+            searchResults.classList.remove("hidden");
+        } else {
+            toc.classList.remove("hidden");
+            searchResults.classList.add("hidden");
+        }
+    }
+
+    async function handleSearchInput() {
+        // get search query
+        const query = searchBox.value;
+        if (query == "") {
+            updateSearchResults([]);
+            return
+        }
+        // make request
+        const response = await fetch("/search/" + query);
+        if (!response.ok) {
+            throw new Error("Couldn't search, status code ", response.status);
+        }
+        let result = await response.text();
+        updateSearchResults(result.split('\n'));
+    }
+
+    searchBox.addEventListener("input", handleSearchInput);
+})();

public/static/style.css

@@ -7,10 +7,11 @@ body {
     width: 100vw;
     font-family: sans-serif;
 }
-a:hover { text-decoration: underline; }
+a:hover, a:focus { text-decoration: underline; }
 a {
     color: black;
     text-decoration: none;
+    outline: none;
 }
 
 .homebtn {
@@ -36,16 +37,34 @@ a {
 }
 .content { white-space: pre-line; }
 
-.toc {
+.home-main {
-    box-sizing: border-box;
-    padding: 2rem;
     width: 100%;
+    padding: 2rem;
+    box-sizing: border-box;
+    gap: 1rem;
+}
+.home-main, .toc, #search-results {
+    display: flex;
+    flex-direction: column;
+}
+.toc, #search-results, #search-box { padding: 0 .2rem; }
+.toc, #search-results { gap: .2rem; }
+#search-box {
+    width: 100%;
+    border: none;
+    outline: none;
+    border-bottom: 1px solid #00000040;
+    height: 2rem;
+    font-size: 1rem;
+}
+#search-box:active, #search-box:focus, #search-box:hover {
+    border-bottom: 1px solid black;
 }
 
+.hidden { display: none !important; }
+
 @media only screen and (max-width: 750px) {
-    .main {
+    .main { margin-top: 4rem; }
-        margin-top: 4rem;
-    }
     .main > h1, .content {
         width: 90vw;
         max-width: unset;

settings.go

@@ -1,7 +1,10 @@
 package main
 
-var ServerListen = ":7000"
+import "golang.org/x/text/language"
-var EntriesDirectory = "./entries"
+
-var TemplateFile = "./public/index.html"
+const ServerListen = ":7000"
-var StaticDirectory = "./public/static"
+const EntriesDirectory = "./entries"
-var MainTitle = "Encyclopedia"
+const TemplateFile = "./public/index.html"
+const StaticDirectory = "./public/static"
+const MainTitle = "Encyclopedia"
+var ContentLanguage = language.English