Merge pull request #1 from MikunoNaka/anime

Merging anime branch into main, with all the currently available API endpoints implemented and working (not sure if properly)

10 files changed, 687 insertions, 33 deletions

diff --git a/anime/anime.go b/anime/anime.go
index 5d054ab..3344016 100644
--- a/anime/anime.go
+++ b/anime/anime.go
@@ -1,40 +1,250 @@
+/* mal2go - MyAnimeList V2 API wrapper for Go
+ * Copyright (C) 2022  Vidhu Kant Sharma <vidhukant@protonmail.ch>
+
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>. */
+
 package anime
 
 import (
 	"encoding/json"
+	"errors"
 	"fmt"
-	"io/ioutil"
-	"log"
-	"net/http"
+	"strconv"
 )
 
-func GetAnimeById(token string, animeId int) Anime {
-  client := &http.Client{}
-  endpoint := fmt.Sprintf("https://api.myanimelist.net/v2/anime/%d?fields=id,title,main_picture,alternative_titles,start_date,end_date,synopsis,mean,rank,popularity,num_list_users,num_scoring_users,nsfw,created_at,updated_at,media_type,status,genres,my_list_status,num_episodes,start_season,broadcast,source,average_episode_duration,rating,pictures,background,related_anime,related_manga,recommendations,studios,statistics", animeId)
+const BASE_URL string = "https://api.myanimelist.net/v2/anime"
 
-  // generate request
-  req, err := http.NewRequest("GET", endpoint, nil)
-  if err != nil {
-      log.Fatal(err)
+// in MAL documentation this is named Get Anime List
+func SearchAnime(token, searchString string, limit, offset int, fields []string) (AnimeSearch, error) {
+  var searchResults AnimeSearch
+
+  // error handling for limit and offset
+  limitsErr := limitsErrHandler(limit, offset)
+  if limitsErr != nil {
+    return searchResults, limitsErr
   }
-  req.Header.Add("Authorization", token)
-  // req.Header.Add("Content-Type", "application/json")
 
-  // do request
-  res, err := client.Do(req)
+  // handle all the errors for the fields
+  fields, err := fieldsErrHandler(fields)
   if err != nil {
-      log.Fatal(err)
+    return searchResults, err
   }
-  defer res.Body.Close()
 
-  body, err := ioutil.ReadAll(res.Body)
-  if err != nil {
-      log.Fatal(err)
+  // generate endpoint url with custom params
+  endpoint, _ := urlGenerator(
+    BASE_URL,
+    []string{"q", "limit", "offset", "fields"},
+    [][]string{{searchString}, {strconv.Itoa(limit)}, {strconv.Itoa(offset)}, fields},
+    true,
+  )
+
+  // gets data from API and stores it in a struct
+  var animeSearchData AnimeSearchRaw
+  data := requestHandler(token, endpoint)
+  json.Unmarshal([]byte(data), &animeSearchData)
+
+  // Adding all the animes to another list to get formatted results later
+  var animes []Anime
+  for _, element := range animeSearchData.Data {
+    animes = append(animes, element.Anime)
   }
-  data := string(body)
 
+  // finally generate AnimeList 
+  searchResults = AnimeSearch {
+    Animes: animes,
+    Paging: animeSearchData.Paging,
+  }
+
+  return searchResults, nil
+}
+
+// Each anime has its own ID on MAL
+func GetAnimeById(token string, animeId int, fields []string) (Anime, error) {
   var anime Anime
+
+  // handle all the errors for the fields
+  fields, err := fieldsErrHandler(fields)
+  if err != nil {
+    return anime, err
+  }
+
+  endpoint, _ := urlGenerator(
+    BASE_URL + "/" + strconv.Itoa(animeId),
+    []string{"fields"},
+    /* it seems to still return all fields from the API. 
+     * this might be an issue with MAL itself
+     * TODO: look into this */
+    [][]string{fields},
+    true,
+  )
+
+  data := requestHandler(token, endpoint)
   json.Unmarshal([]byte(data), &anime)
 
-  return anime
+  return anime, nil
+}
+
+// Ranking is a list of anime sorted by their rank
+func GetAnimeRanking(token string, rankingType string, limit, offset int, fields []string) (AnimeRanking, error) {
+  var animeRanking AnimeRanking
+
+  // error handling for limit and offset
+  limitsErr := limitsErrHandler(limit, offset)
+  if limitsErr != nil {
+    return animeRanking, limitsErr
+  }
+
+  // handle all the errors for the fields
+  fields, err := fieldsErrHandler(fields)
+  if err != nil {
+    return animeRanking, err
+  }
+
+  // if ranking type is invalid
+  if !isValidRankingType(rankingType) {
+    return animeRanking, errors.New(fmt.Sprintf("GetAnimeRanking: Invalid ranking type specified: \"%s\"", rankingType))
+  }
+
+  endpoint, _ := urlGenerator(
+    BASE_URL + "/ranking",
+    []string{"ranking_type", "limit", "offset", "fields"},
+    [][]string{{rankingType}, {strconv.Itoa(limit)}, {strconv.Itoa(offset)}, fields},
+    true,
+  )
+
+  // gets data from API and stores it in a struct
+  var rankingData RawRanking
+  data := requestHandler(token, endpoint)
+  json.Unmarshal([]byte(data), &rankingData)
+
+  // Adding all the animes in ranking list to a slice
+  var animeRankingTitles []AnimeRankingTitle
+  for _, element := range rankingData.Data {
+    animeRankingTitles = append(
+      animeRankingTitles,
+      AnimeRankingTitle {
+        Anime:   element.Anime, 
+        RankNum: element.Ranking.Rank,
+      },
+    )
+  }
+
+  // Finally, create the AnimeRanking object
+  animeRanking = AnimeRanking {
+    Titles: animeRankingTitles,
+    Paging: ListPaging {
+      NextPage: rankingData.Paging.NextPage,
+      PrevPage: rankingData.Paging.PrevPage,
+    },
+  }
+
+  return animeRanking, nil
+}
+
+// get list of animes from specified season
+func GetSeasonalAnime(token, year, season, sort string, limit, offset int, fields []string) (SeasonalAnime, error) {
+  var seasonalAnime SeasonalAnime
+
+  // error handling for limit and offset
+  limitsErr := limitsErrHandler(limit, offset)
+  if limitsErr != nil {
+    return seasonalAnime, limitsErr
+  }
+
+  // handle all the errors for the fields
+  fields, err := fieldsErrHandler(fields)
+  if err != nil {
+    return seasonalAnime, err
+  }
+
+  // checks if valid season is specified
+  if !isValidSeason(season) {
+    return seasonalAnime, errors.New(fmt.Sprintf("GetSeasonalAnime: Invalid season specified: \"%s\"", season))
+  }
+
+  // checks if valid sort is specified
+  if !isValidSort(sort) {
+    return seasonalAnime, errors.New(fmt.Sprintf("GetSeasonalAnime: Invalid sort specified: \"%s\"", sort))
+  }
+
+  endpoint, _ := urlGenerator(
+    BASE_URL + fmt.Sprintf("/season/%s/%s", year, season),
+    []string{"sort", "limit", "offset", "fields"},
+    [][]string{{sort}, {strconv.Itoa(limit)}, {strconv.Itoa(offset)}, fields},
+    true,
+  )
+
+  // gets data from API and stores it in a struct
+  var seasonalAnimeData SeasonalAnimeRaw
+  data := requestHandler(token, endpoint)
+  json.Unmarshal([]byte(data), &seasonalAnimeData)
+
+  // Adding all the animes to another list to get formatted results later
+  var animes []Anime
+  for _, element := range seasonalAnimeData.Data {
+    animes = append(animes, element.Anime)
+  }
+
+  // finally generate SeasonalAnime
+  seasonalAnime = SeasonalAnime {
+    Animes: animes,
+    Paging: seasonalAnimeData.Paging,
+    Season: seasonalAnimeData.Season,
+  }
+
+  return seasonalAnime, nil
+}
+
+// get anime suggestions for the user
+func GetSuggestedAnime(token string, limit, offset int, fields []string) (SuggestedAnime, error){
+  var suggestedAnime SuggestedAnime
+
+  // error handling for limit and offset
+  limitsErr := limitsErrHandler(limit, offset)
+  if limitsErr != nil {
+    return suggestedAnime, limitsErr
+  }
+
+  // handle all the errors for the fields
+  fields, err := fieldsErrHandler(fields)
+  if err != nil {
+    return suggestedAnime, err
+  }
+
+  endpoint, _ := urlGenerator(
+    BASE_URL + "/suggestions",
+    []string{"limit", "offset", "fields"},
+    [][]string{{strconv.Itoa(limit)}, {strconv.Itoa(offset)}, fields},
+    true,
+  )
+
+  // gets data from API and stores it in a struct
+  var suggestedAnimeData SuggestedAnimeRaw
+  data := requestHandler(token, endpoint)
+  json.Unmarshal([]byte(data), &suggestedAnimeData)
+
+  // Adding all the animes to another list to get formatted results later
+  var animes []Anime
+  for _, element := range suggestedAnimeData.Data {
+    animes = append(animes, element.Anime)
+  }
+
+  // finally generate RecommendedAnime struct
+  suggestedAnime = SuggestedAnime {
+    Animes: animes,
+    Paging: suggestedAnimeData.Paging,
+  }
+
+  return suggestedAnime, nil
 }
diff --git a/anime/structs.go b/anime/anime.structs.go
index bb35ded..1599e6d 100644
--- a/anime/structs.go
+++ b/anime/anime.structs.go
@@ -1,3 +1,19 @@
+/* mal2go - MyAnimeList V2 API wrapper for Go
+ * Copyright (C) 2022  Vidhu Kant Sharma <vidhukant@protonmail.ch>
+
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>. */
+
 package anime
 
 type AnimePicture struct {
@@ -6,11 +22,11 @@ type AnimePicture struct {
 }
 
 type StatusStatistics struct {
-  Watching    int `json:"watching"` 
-  Completed   int `json:"completed"`
-  OnHold      int `json:"on_hold"`
-  Dropped     int `json:"dropped"`
-  PlanToWatch int `json:"plan_to_watch"`
+  Watching    string `json:"watching"` 
+  Completed   string `json:"completed"`
+  OnHold      string `json:"on_hold"`
+  Dropped     string `json:"dropped"`
+  PlanToWatch string `json:"plan_to_watch"`
 }
 
 type AnimeStatistics struct {
@@ -31,11 +47,6 @@ type ListStatus struct {
   UpdatedAt    string `json:"updated_at"`
 }
 
-type Season struct {
-  Year int    `json:"year"`
-  Name string `json:"season"`
-}
-
 type Broadcast struct {
   Day  string `json:"day_of_the_week"`
   Time string `json:"start_time"`
@@ -57,11 +68,17 @@ type Recommendation struct {
   Num   int   `json:"num_recommendations"`
 }
 
+type AltTitles struct {
+  Synonyms []string `json:"synonyms"`
+  En       string   `json:"en"`
+  Ja       string   `json:"ja"`
+}
+
 type Anime struct {
   Id                int              `json:"id"`
   Title             string           `json:"title"`
   MainPicture       AnimePicture     `json:"main_picture"`
-  AltTitles         []string         `json:"alternative_titles"`
+  AltTitles         AltTitles        `json:"alternative_titles"`
   StartDate         string           `json:"start_date"`
   EndDate           string           `json:"end_date"`
   Synopsis          string           `json:"synopsis"`
@@ -70,7 +87,11 @@ type Anime struct {
   Popularity        int              `json:"popularity"`
   NumListUsers      int              `json:"num_list_users"`
   NumScoringUsers   int              `json:"num_scoring_users"`
-  NsfwStatus        string           `json:"nsfw"` // find out what values are there
+  /* NsfwStatus potential values:
+   *  white = sfw
+   *  gray  = probably nsfw
+   *  black = nsfw */
+  NsfwStatus        string           `json:"nsfw"`
   CreatedAt         string           `json:"created_at"`
   UpdatedAt         string           `json:"updated_at"`
   MediaType         string           `json:"media_type"`
@@ -82,6 +103,7 @@ type Anime struct {
   Broadcast         Broadcast        `json:"broadcast"`
   Source            string           `json:"source"`
   DurationSeconds   int              `json:"average_episode_duration"`
+  // Rating as in R, PG13, etc
   Rating            string           `json:"rating"`
   Pictures          []AnimePicture   `json:"pictures"`
   Background        string           `json:"background"`
diff --git a/anime/errhandlers.go b/anime/errhandlers.go
new file mode 100644
index 0000000..d7f70f9
--- /dev/null
+++ b/anime/errhandlers.go
@@ -0,0 +1,71 @@
+/* mal2go - MyAnimeList V2 API wrapper for Go
+ * Copyright (C) 2022  Vidhu Kant Sharma <vidhukant@protonmail.ch>
+
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>. */
+
+package anime
+
+import (
+  "errors"
+  "fmt"
+)
+
+/* NOTE: MAL still seems to send some fields 
+ * even if they aren't requested.
+ * those include Title, Picture, Id, etc */
+// default fields to use when none are specified
+var defaultFields []string = []string{
+  "id", "title", "main_picture",
+  "alternative_titles", "start_date",
+  "end_date", "synopsis", "mean", "rank",
+  "popularity", "num_list_users",
+  "num_scoring_users", "nsfw", "created_at",
+  "updated_at", "media_type", "status",
+  "genres", "my_list_status", "num_episodes",
+  "start_season", "broadcast", "source",
+  "average_episode_duration", "rating",
+  "pictures", "background", "related_anime",
+  "related_manga", "recommendations",
+  "studios", "statistics",
+}
+
+// if fields aren't specified
+func fieldsErrHandler(fields []string) ([]string, error) {
+  if cap(fields) == 0 {
+    // uses all the default fields if none specified
+    return defaultFields, nil
+  }
+
+  // checks if each given field is valid
+  for _, j := range(fields) {
+    if !isValidField(j) {
+      return []string{}, errors.New(fmt.Sprintf("InvalidFieldError: Invalid field specified: \"%s\"", j))
+    }
+  }
+
+  // everything's fine!
+  return fields, nil
+}
+
+// if limit or error specified are above the limit
+func limitsErrHandler(limit, offset int) error {
+  maxOffset := 500 - limit
+  if limit > 500 {
+    return errors.New(fmt.Sprintf("InvalidLimitError: Limit specified too high (%d > 500).", limit))
+  } else if offset > maxOffset {
+    return errors.New(fmt.Sprintf("InvalidOffsetError: Offset specified too high (%d > %d).", offset, maxOffset))
+  }
+  // return nil if no error
+  return nil
+}
diff --git a/anime/general.structs.go b/anime/general.structs.go
new file mode 100644
index 0000000..c49b762
--- /dev/null
+++ b/anime/general.structs.go
@@ -0,0 +1,28 @@
+/* mal2go - MyAnimeList V2 API wrapper for Go
+ * Copyright (C) 2022  Vidhu Kant Sharma <vidhukant@protonmail.ch>
+
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>. */
+
+package anime
+
+// contains previous/next page for anime list
+type ListPaging struct {
+  NextPage string `json:"next"`
+  PrevPage string `json:"previous"` // might need checking
+}
+
+type Season struct {
+  Year int    `json:"year"`
+  Name string `json:"season"`
+}
diff --git a/anime/ranking.structs.go b/anime/ranking.structs.go
new file mode 100644
index 0000000..28ae860
--- /dev/null
+++ b/anime/ranking.structs.go
@@ -0,0 +1,41 @@
+/* mal2go - MyAnimeList V2 API wrapper for Go
+ * Copyright (C) 2022  Vidhu Kant Sharma <vidhukant@protonmail.ch>
+
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>. */
+
+package anime
+
+// this is how the API returns data (looks horrible)
+type RawRanking struct {
+  Data []struct {
+    Anime Anime `json:"node"`
+    Ranking struct {
+      Rank int `json:"rank"`
+    } `json:"ranking"`
+  } `json:"data"`
+
+  Paging ListPaging `json:"paging"`
+}
+
+// each anime has a ranking number
+type AnimeRankingTitle struct {
+  Anime   Anime
+  RankNum int
+}
+
+// this is how mal2go returns data
+type AnimeRanking struct {
+  Titles []AnimeRankingTitle
+  Paging ListPaging
+}
diff --git a/anime/search.structs.go b/anime/search.structs.go
new file mode 100644
index 0000000..e59bb44
--- /dev/null
+++ b/anime/search.structs.go
@@ -0,0 +1,32 @@
+/* mal2go - MyAnimeList V2 API wrapper for Go
+ * Copyright (C) 2022  Vidhu Kant Sharma <vidhukant@protonmail.ch>
+
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>. */
+
+package anime
+
+// this is how the API returns data (looks horrible)
+type AnimeSearchRaw struct {
+  Data []struct {
+    Anime Anime `json:"node"`
+  } `json:"data"`
+
+  Paging ListPaging `json:"paging"`
+}
+
+// this is how mal2go returns data
+type AnimeSearch struct {
+  Animes []Anime
+  Paging ListPaging
+}
diff --git a/anime/seasonal.structs.go b/anime/seasonal.structs.go
new file mode 100644
index 0000000..06bda42
--- /dev/null
+++ b/anime/seasonal.structs.go
@@ -0,0 +1,34 @@
+/* mal2go - MyAnimeList V2 API wrapper for Go
+ * Copyright (C) 2022  Vidhu Kant Sharma <vidhukant@protonmail.ch>
+
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>. */
+
+package anime
+
+// this is how the API returns data (looks horrible)
+type SeasonalAnimeRaw struct {
+  Data []struct {
+    Anime Anime `json:"node"`
+  } `json:"data"`
+
+  Paging ListPaging `json:"paging"`
+  Season Season     `json:"season"`
+}
+
+// this is how mal2go returns data
+type SeasonalAnime struct {
+  Animes []Anime
+  Paging ListPaging
+  Season Season
+}
diff --git a/anime/suggestedanime.structs.go b/anime/suggestedanime.structs.go
new file mode 100644
index 0000000..a7b3a60
--- /dev/null
+++ b/anime/suggestedanime.structs.go
@@ -0,0 +1,31 @@
+/* mal2go - MyAnimeList V2 API wrapper for Go
+ * Copyright (C) 2022  Vidhu Kant Sharma <vidhukant@protonmail.ch>
+
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>. */
+
+package anime
+
+// this is how the API returns data (looks horrible)
+type SuggestedAnimeRaw struct {
+  Data []struct {
+    Anime Anime `json:"node"`
+  } `json:"data"`
+  Paging ListPaging `json:"paging"`
+}
+
+// this is how mal2go returns data
+type SuggestedAnime struct {
+  Animes []Anime
+  Paging ListPaging
+}
diff --git a/anime/util.go b/anime/util.go
new file mode 100644
index 0000000..f1f3b2a
--- /dev/null
+++ b/anime/util.go
@@ -0,0 +1,89 @@
+/* mal2go - MyAnimeList V2 API wrapper for Go
+ * Copyright (C) 2022  Vidhu Kant Sharma <vidhukant@protonmail.ch>
+
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>. */
+
+package anime
+
+import (
+	"io/ioutil"
+	"log"
+	"net/http"
+  "errors"
+)
+
+// Handles HTTP request with your OAuth token as a Header
+// TODO: Verify that this function is safe to use
+func requestHandler(token string, endpoint string) string {
+  client := &http.Client{}
+
+  // generate request
+  req, err := http.NewRequest("GET", endpoint, nil)
+  if err != nil {
+      log.Fatal(err)
+  }
+  req.Header.Add("Authorization", token)
+
+  // do request
+  res, err := client.Do(req)
+  if err != nil {
+      log.Fatal(err)
+  }
+  defer res.Body.Close()
+
+  // read body
+  body, err := ioutil.ReadAll(res.Body)
+  if err != nil {
+      log.Fatal(err)
+  }
+
+  return string(body)
+}
+
+func urlGenerator(baseUrl string, names []string, values [][]string, isPrimary bool) (string, error) {
+  // length of names and values should be same
+  if cap(names) != cap(values) {
+    return "", errors.New("urlGenerator: Error: Length of names and values don't match.")
+  }
+
+  var fields string
+
+  for index, name := range(names) {
+    var data string
+    /* if the data is the first field in URL, 
+     * it goes like ?key=value
+     * else it is &nextkey=value */
+    if isPrimary {
+      data = "?" + name + "="
+    } else {
+      data = "&" + name + "="
+    }
+
+    // add values to data variable
+    for i, j := range values[index] {
+      if i > 0 {
+        data = data + "," + j
+      } else {
+        data = data + j 
+      }
+    }
+
+    fields = fields + data
+
+    // from now on all other fields will be secondary
+    isPrimary = false
+  }
+
+  return baseUrl + fields, nil
+}
diff --git a/anime/validators.go b/anime/validators.go
new file mode 100644
index 0000000..7f6a7cc
--- /dev/null
+++ b/anime/validators.go
@@ -0,0 +1,96 @@
+/* mal2go - MyAnimeList V2 API wrapper for Go
+ * Copyright (C) 2022  Vidhu Kant Sharma <vidhukant@protonmail.ch>
+
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>. */
+
+package anime
+
+// Checks if given rankingType is valid
+func isValidRankingType(rankingType string) bool {
+  switch rankingType {
+    case
+      "all",
+      "airing",
+      "upcoming",
+      "tv",
+      "ova",
+      "movie",
+      "special",
+      "bypopularity",
+      "favorite": return true
+    }
+  return false
+}
+
+// Checks if given rankingType is valid
+func isValidField(field string) bool {
+  switch field {
+    case
+      "id",
+      "title",
+      "main_picture",
+      "alternative_titles",
+      "start_date",
+      "end_date",
+      "synopsis",
+      "mean",
+      "rank",
+      "popularity",
+      "num_list_users",
+      "num_scoring_users",
+      "nsfw",
+      "created_at",
+      "updated_at",
+      "media_type",
+      "status",
+      "genres",
+      "my_list_status",
+      "num_episodes",
+      "start_season",
+      "broadcast",
+      "source",
+      "average_episode_duration",
+      "rating",
+      "pictures",
+      "background",
+      "related_anime",
+      "related_manga",
+      "recommendations",
+      "studios",
+      "statistics": return true
+    }
+  return false
+}
+
+// Checks if given season is valid
+func isValidSeason(season string) bool {
+  switch season {
+    case
+      "winter",
+      "spring",
+      "summer",
+      "fall": return true
+    }
+  return false
+}
+
+// Checks if given sort is valid
+func isValidSort(sort string) bool {
+  switch sort {
+    case
+      "anime_score",
+      "anime_num_list_users": return true
+    }
+  return false
+}