# Lendo o endpoint de Comics

A Marvel API nos disponibiliza alguns recursos legais, como obter personagens, historias em quadrinho, eventos, séries, entre outros.

Para ver todos os *endpoints*, só acessar o [link da documentação](https://developer.marvel.com/docs) e teremos ali uma lista completa dos recursos e como devemos montar nossas requisições. 

Em nosso estudo, utilizarei a listagem de Comics (revistas em quadrinhos)

<figure><img src="/files/JYJws4KlyBqbtGRvrUaU" alt=""><figcaption><p><a href="https://developer.marvel.com/docs#!/public/getComicsCollection_get_6">https://developer.marvel.com/docs#!/public/getComicsCollection_get_6</a></p></figcaption></figure>

Vamos extrair as informações para conseguir realizar a requisição igual como fizemos em nosso [serviço de cafés quentes](/construindo-um-cliente-usando-tesla/criando-o-client.md).

Olhando apenas o básico temos essa estrutura

```
GET https://<url_base>/v1/public/comics
```

Temos aqui&#x20;

| **Verbo**    | GET               |   |
| ------------ | ----------------- | - |
| **Recurso**  | /v1/public/comics |   |
| **URL base** | ?                 |   |

Mas esta faltando a URL base de nossa requisição. Para essa informação, podemos acessar o [General API Information](https://developer.marvel.com/documentation/getting_started). e veremos que nossa base é `https://gateway.marvel.com/`

| **Verbo**    | GET                          |
| ------------ | ---------------------------- |
| **Recurso**  | /v1/public/comics            |
| **URL base** | <https://gateway.marvel.com> |

Podemos agora montar nossa requisição e testala com o Tesla.

```
GET https://gateway.marvel.com/v1/public/comics
```

Convertendo

```elixir
Tesla.get("https://gateway.marvel.com/v1/public/comics")
```

Podemos acessar nosso terminal iterativo e testar a requisição

```
iex -S mix   
```

```elixir
Tesla.get("https://gateway.marvel.com/v1/public/comics")
```

```elixir
iex(1)> Tesla.get("https://gateway.marvel.com/v1/public/comics")
{:ok,
 %Tesla.Env{
   method: :get,
   url: "https://gateway.marvel.com/v1/public/comics",
   query: [],
   headers: [
     {"connection", "keep-alive"},
     {"date", "Wed, 08 May 2024 17:57:08 GMT"},
     {"content-length", "68"},
     {"content-type", "application/json; charset=utf-8"}
   ],
   body: "{\"code\":\"MissingParameter\",\"message\":\"You must provide a user key.\"}",
   status: 409,
   opts: [],
   __module__: Tesla,
   __client__: %Tesla.Client{fun: nil, pre: [], post: [], adapter: nil}
 }}
```

Aqui temos nosso primeiro problema. Mesmo a API sendo publica, temos controle de quem está acessando. Nesse caso ele avisa que precisamos de um chave de usuário. E foi para isso que criamos uma conta na Marvel.

[Acesse sua conta de desenvolvedor](https://developer.marvel.com/account) e iremos encontrar a chave necessária. Sua API Key é sua chave pública. Marquei de amarelo.&#x20;

<figure><img src="/files/oHY10jNqZ11T9GRJnmCE" alt=""><figcaption><p><a href="https://developer.marvel.com/account">https://developer.marvel.com/account</a></p></figcaption></figure>

Vou nomear a minha como 12345, para facilitar o entendimento.

| **Verbo**    | GET                          |
| ------------ | ---------------------------- |
| **Recurso**  | /v1/public/comics            |
| **URL base** | <https://gateway.marvel.com> |
| A**pi Key**  | 12345                        |

Vamos atualizar nossa chamada com o Tesla. Para passar esse dado, utilizaremos query params.

{% code fullWidth="false" %}

```elixir
Tesla.get("https://gateway.marvel.com/v1/public/comics?apikey=12345")
```

{% endcode %}

<pre class="language-elixir"><code class="lang-elixir">iex(3)> Tesla.get("https://gateway.marvel.com/v1/public/comics?apikey=d3f934e3c9ccb6de467674e4fc7a3ead")
{:ok,
 %Tesla.Env{
   method: :get,
   url: "https://gateway.marvel.com/v1/public/comics?apikey=d3f934e3c9ccb6de467674e4fc7a3ead",
   query: [],
   headers: [
     {"connection", "keep-alive"},
     {"date", "Wed, 08 May 2024 18:06:59 GMT"},
     {"content-length", "64"},
     {"content-type", "application/json; charset=utf-8"}
   ],
<strong>   body: "{\"code\":\"MissingParameter\",\"message\":\"You must provide a hash.\"}",
</strong>   status: 409,
   opts: [],
   __module__: Tesla,
   __client__: %Tesla.Client{fun: nil, pre: [], post: [], adapter: nil}
 }}
</code></pre>

Passamos do problema da *user key*. Mas caímos agora no problema do *hash*.

O *hash* na API da Marvel é uma encriptação simples usando MD5 que utiliza os dados

| Nome          | Descrição                                                                                                    |
| ------------- | ------------------------------------------------------------------------------------------------------------ |
| TS            | Uma *string* que servirá para termos unicidade nas requisições. Cada requisição deve ter um valor diferente. |
| Chave Publica | Que chamamos acima de *api key*                                                                              |
| Chave privada | Uma chave extra para realizar a *decrypt*. Basicamente, a chave para abrir.                                  |

As chaves encontramos na [conta de de desenvolvedor](https://developer.marvel.com/account).

Marquei em amarelo a <mark style="background-color:yellow;">publica</mark> e rosa a <mark style="background-color:red;">privada</mark>.

<figure><img src="/files/aqTiWyRbm6DovZPOnarY" alt=""><figcaption></figcaption></figure>

Utilizaremos como TS, por hora, o numero 1. Simplesmente para seguir com os estudos.

Como chave privada, demonstrarei como 88888.

A regra para o hash é:

```
<TS>+<chave_privada>+<chave_publica>
```

Podemos criar isso pelo elixir, entrando no modo iterativo

```elixir
:crypto.hash(:md5, "11234588888") |> Base.encode16()
```

```elixir
iex(1)> :crypto.hash(:md5, "11234588888") |> Base.encode16()
"7EE341DFFE88E697114117AA51E1A210"
```

Vamos agora pegar esse valor e adicionar a nossa query param. Também devemos colocar o valor de TS em nosso query o mesmo informado na criação do hash.

{% code fullWidth="false" %}

```elixir
Tesla.get("https://gateway.marvel.com/v1/public/comics?apikey=12345&hash=7EE341DFFE88E697114117AA51E1A210&ts=1")
```

{% endcode %}

<pre class="language-elixir" data-full-width="false"><code class="lang-elixir">iex(1)> Tesla.get("https://gateway.marvel.com/v1/public/comics?apikey=12345&#x26;hash=7EE341DFFE88E697114117AA51E1A210&#x26;ts=1")
{:ok,
 %Tesla.Env{
   method: :get,
   url: "https://gateway.marvel.com/v1/public/comics?apikey=d3f934e3c9ccb6de467674e4fc7a3ead&#x26;ts=1&#x26;hash=1d49870a0631827587878fcff98fa267",
   query: [],
   headers: [
     {"connection", "keep-alive"},
     {"date", "Wed, 08 May 2024 18:21:51 GMT"},
     {"etag", "60ddd4a67c6e3242fa2560dbb0035b3925d666ef"},
     {"content-length", "66553"},
     {"content-type", "application/json; charset=utf-8"}
   ],
<strong>   body: "{\"code\":200,\"status\":\"Ok\",\"copyright\":\"© 2024 MARVEL\",\"attributionText\":\"Data provided by Marvel. © 2024 MARVEL\",\"attributionHTML\":\"&#x3C;a href=\\\"http://marvel.com\\\">Data provided by Marvel. © 2024 MARVEL&#x3C;/a>\",\"etag\":\"60ddd4a67c6e3242fa2560dbb0035b3925d666ef\",\"data\":{\"offset\":0,\"limit\":20,\"total\":60239,\"count\":20,\"results\":[{\"id\":82967,\"digitalId\":0,\"title\":\"Marvel Previews (2017)\",\"issueNumber\":0,\"variantDescription\":\"\",\"description\":\"\",\"modified\":\"2019-11-07T08:46:15-0500\",\"isbn\":\"\",\"upc\":\"75960608839302811\",\"diamondCode\":\"\",\"ean\":\"\",\"issn\":\"\",\"format\":\"\",\"pageCount\":112,\"textObjects\":[],\"resourceURI\":\"http://gateway.marvel.com/v1/public/comics/82967\",\"urls\":[{\"type\":\"detail\",\"url\":\"http://marvel.com/comics/issue/82967/marvel_previews_2017?utm_campaign=apiRef&#x26;utm_source=25a07f7adccf7328d3153451c26bd992\"}],\"series\":{\"resourceURI\":\"http://gateway.marvel.com/v1/public/series/23665\",\"name\":\"Marvel Previews (2017 - Present)\"},\"variants\":[{\"resourceURI\":\"http://gateway.marvel.com/v1/public/comics/82965\",\"name\":\"Marvel Previews (2017)\"},{\"resourceURI\":\"http://gateway.marvel.com/v1/public/comics/82970\",\"name\":\"Marvel Previews (2017)\"},{\"resourceURI\":\"http://gateway.marvel.com/v1/public/comics/82969\",\"name\":\"Marvel Previews (2017)\"},{\"resourceURI\":\"http://gateway.marvel.com/v1/public/comics/74697\",\"name\":\"Marvel Previews (2017)\"},{\"resourceURI\":\"http://gateway.marvel.com/v1/public/comics/72736\",\"name\":\"Marvel Previews (2017)\"},{\"resourceURI\":\"http://gateway.marvel.com/v1/public/comics/75668\",\"name\":\"Marvel Previews (2017)\"},{\"resourceURI\":\"http://gateway.marvel.com/v1/public/comics/65364\",\"name\":\"Marvel Previews (2017)\"},{\"resourceURI\":\"http://gateway.marvel.com/v1/public/comics/65158\",\"name\":\"Marvel Previews (2017)\"},{\"resourceURI\":\"http://gateway.marvel.com/v1/public/comics/65028\",\"name\":\"Marvel Previews (2017)\"},{\"resourceURI\":\"http://gateway.marvel.com/v1/public/comics/75662\",\"name\":\"Marvel Previews (2017)\"},{\"resourceURI\":\"http://gateway.marvel.com/v1/public/comics/74320\",\"name\":\"Marvel Previews (2017)\"},{\"resourceURI\":\"http://gateway.marvel.com/v1/public/comics/73776\",\"name\":\"Marvel Previews (2017)\"}],\"collections\":[],\"collectedIssues\":[],\"dates\":[{\"type\":\"onsaleDate\",\"date\":\"2099-10-30T00:00:00-0500\"},{\"type\":\"focDate\",\"date\":\"2019-10-07T00:00:00-0400\"}],\"prices\":[{\"type\":\"printPrice\",\"price\":0}],\"thumbnail\":{\"path\":\"http://i.annihil.us/u/prod/marvel/i/mg/b/40/image_not_available\",\"extension\":\"jpg\"},\"images\":[],\"creators\":{\"available\":1,\"collectionURI\":\"http://gateway.marvel.com/v1/public/comics/82967/creators\",\"items\":[{\"resourceURI\":\"http://gateway.marvel.com/v1/public/creators/10021\",\"name\":\"Jim Nausedas\",\"role\":\"editor\"}],\"returned\":1},\"characters\":{\"available\":0,\"collectionURI\":\"http://gateway.marvel.com/v1/public/comics/82967/characters\",\"items\":[],\"returned\":0},\"stories\":{\"available\":2,\"collectionURI\":\"http://gateway.marvel.com/v1/public/comics/82967/stories\",\"items\":[{\"resourceURI\":\"http://gateway.marvel.com/v1/public/stories/183698\",\"name\":\"cover from Marvel Previews (2017)\",\"type\":\"cover\"},{\"resourceURI\":\"http://gateway.marvel.com/v1/public/stories/183699\",\"name\":\"story from Marvel Previews (2017)\",\"type\":\"interiorStory\"}],\"returned\":2},\"events\":{\"available\":0,\"collectionURI\":\"http://gateway.marvel.com/v1/public/comics/82967/events\",\"items\":[],\"returned\":0}},{\"id\":82965,\"digitalId\":0,\"title\":\"Marvel Previews (2017)\",\"issueNumber\":0,\"variantDescription\":\"\",\"description\":\"\",\"modified\":\"2019-08-21T17:11:27-0400\",\"isbn\":\"\",\"upc\":\"75960608839302611\",\"diamondCode\":\"JUL190068\",\"ean\":\"\",\"issn\":\"\",\"format\":\"\",\"pageCount\":152,\"textObjects\":[],\"resourceURI\":\"http://gateway.marvel.com/v1/public/comics/82965\",\"urls\":[{\"type\":\"detail\",\"url\":\"http://marvel.com/comics/issue/82965/marvel_previews_2017?utm_campaign=apiRef&#x26;utm_source=25a07f7adccf7328d3153451c26bd992\"}],\"series\":{\"resourceURI\":\"http://gateway.marvel.com/v1/public/series/23665\",\"name\":\"Marvel Previews (2017 - Present)\"},\"variants\":[{\"resourceURI\":\"http://gateway.marvel.com/v1/public/comics/82967\",\"name\":\"Marvel Previews (2017)\"},{\"resourceURI\":\"http://gateway.marvel.co" &#x3C;> ...,
</strong>   status: 200,
   opts: [],
   __module__: Tesla,
   __client__: %Tesla.Client{fun: nil, pre: [], post: [], adapter: nil}
 }}
</code></pre>

Pronto, estamos com todo acesso necessário para utilizar a API da Marvel. Bora escrever nosso cliente.&#x20;


---

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```
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