Added Wikipedia backlinks api support

gowiki.go

@@ -342,3 +342,53 @@ func Summary(title string, numsentence int, numchar int, suggest bool, redirect
 
 	return res.Query.Page[strconv.Itoa(page.PageID)].Extract, nil
 }
+
+/*
+Get a list of pages which link to a certain page.
+
+Keyword arguments:
+
+* title: The title of the page you want the backlinks
+
+Return:
+
+* List of titles of Wikipedia pages that links to the page.
+
+* Error
+*/
+func GetBacklinks(title string) ([]string, error) {
+	var backlinks []string
+	last := ""
+	args := map[string]string{
+		"action":  "query",
+		"list":    "backlinks",
+		"bltitle": title,
+		"bllimit": "max",
+	}
+
+	for {
+		if last != "" {
+			args["blcontinue"] = last
+		}
+
+		res, err := utils.WikiRequester(args)
+		if err != nil {
+			return []string{}, err
+		}
+		if res.Error.Code != "" {
+			return []string{}, errors.New(res.Error.Info)
+		}
+
+		for _, s := range res.Query.Backlinks {
+			backlinks = append(backlinks, s.Title)
+		}
+
+		blcontinue := res.Continue["blcontinue"]
+		if blcontinue == nil {
+			break
+		}
+		last = blcontinue.(string)
+	}
+
+	return backlinks, nil
+}

models/models.go

@@ -66,6 +66,10 @@ type InnerNormalize struct {
 	To   string `json:"to"`
 }
 
+type InnerBacklinks struct {
+	Title string `json:"title"`
+}
+
 type RequestQuery struct {
 	SearchInfo InnerSearchInfo      `json:"searchinfo"`
 	Normalize  []InnerNormalize     `json:"normalized"`
@@ -75,6 +79,7 @@ type RequestQuery struct {
 	Page       map[string]InnerPage `json:"pages"`
 	Random     []InnerSearch        `json:"random"`
 	Language   []map[string]string  `json:"languages"`
+	Backlinks  []InnerBacklinks     `json:"backlinks"`
 }
 
 /*

test/backlinks_test.go

@@ -0,0 +1,21 @@
+package test
+
+import (
+	"testing"
+
+	gowiki "github.com/trietmn/go-wiki"
+	"github.com/trietmn/go-wiki/utils"
+)
+
+func TestBacklinks(t *testing.T) {
+	utils.WikiRequester = MockRequester
+	expectation := utils.TurnSliceOfString(MockData["great_wall_of_china.backlinks"].([]interface{}))
+	res, err := gowiki.GetBacklinks("Great Wall of China")
+	if err != nil {
+		t.Errorf("%v", err)
+	}
+	if !utils.CompareSlice(res, expectation) {
+		t.Errorf("got %v, expect %v", res, expectation)
+	}
+
+}

test/mock_data.json

@@ -188,5 +188,33 @@
     "great_wall_of_china.geo_search_with_existing_article_name": [
         "Great Wall of China"
     ],
-    "great_wall_of_china.geo_search_with_non_existing_article_name": []
+    "great_wall_of_china.geo_search_with_non_existing_article_name": [],
+    "great_wall_of_china.backlinks": [
+        "Army",
+        "China",
+        "Conscription",
+        "History of China",
+        "Civil engineering",
+        "Civilization (video game)",
+        "Empire",
+        "Factoid",
+        "Göktürks",
+        "Ibn Battuta",
+        "Keno",
+        "Khunjerab Pass",
+        "Mongols",
+        "Mongolia",
+        "Marco Polo",
+        "May 25",
+        "Microevolution",
+        "Mississippi River",
+        "Shang-Chi",
+        "Nanotechnology",
+        "Geography of China",
+        "Telecommunications in China",
+        "Qing dynasty",
+        "Richard Nixon",
+        "Sabah",
+        "Shaolin Monastery"
+    ]
 }

test/mock_wiki_request.json

@@ -1475,5 +1475,37 @@
         "query": {
             "geosearch": []
         }
+    },
+    "action:query;list:backlinks;bltitle:Great Wall of China;bllimit:max": {
+        "query": {
+            "backlinks": [
+                    {"Title": "Army"},
+                    {"Title": "China"},
+                    {"Title": "Conscription"},
+                    {"Title": "History of China"},
+                    {"Title": "Civil engineering"},
+                    {"Title": "Civilization (video game)"},
+                    {"Title": "Empire"},
+                    {"Title": "Factoid"},
+                    {"Title": "Göktürks"},
+                    {"Title": "Ibn Battuta"},
+                    {"Title": "Keno"},
+                    {"Title": "Khunjerab Pass"},
+                    {"Title": "Mongols"},
+                    {"Title": "Mongolia"},
+                    {"Title": "Marco Polo"},
+                    {"Title": "May 25"},
+                    {"Title": "Microevolution"},
+                    {"Title": "Mississippi River"},
+                    {"Title": "Shang-Chi"},
+                    {"Title": "Nanotechnology"},
+                    {"Title": "Geography of China"},
+                    {"Title": "Telecommunications in China"},
+                    {"Title": "Qing dynasty"},
+                    {"Title": "Richard Nixon"},
+                    {"Title": "Sabah"},
+                    {"Title": "Shaolin Monastery"}
+            ]
+        }
     }
 }