esp_http_client.h 23 KB

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  1. // Copyright 2015-2018 Espressif Systems (Shanghai) PTE LTD
  2. //
  3. // Licensed under the Apache License, Version 2.0 (the "License");
  4. // you may not use this file except in compliance with the License.
  5. // You may obtain a copy of the License at
  6. // http://www.apache.org/licenses/LICENSE-2.0
  7. //
  8. // Unless required by applicable law or agreed to in writing, software
  9. // distributed under the License is distributed on an "AS IS" BASIS,
  10. // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  11. // See the License for the specific language governing permissions and
  12. // limitations under the License.
  13. #ifndef _ESP_HTTP_CLIENT_H
  14. #define _ESP_HTTP_CLIENT_H
  15. #include "freertos/FreeRTOS.h"
  16. #include "http_parser.h"
  17. #include "sdkconfig.h"
  18. #include "esp_err.h"
  19. #ifdef __cplusplus
  20. extern "C" {
  21. #endif
  22. #define DEFAULT_HTTP_BUF_SIZE (512)
  23. typedef struct esp_http_client *esp_http_client_handle_t;
  24. typedef struct esp_http_client_event *esp_http_client_event_handle_t;
  25. /**
  26. * @brief HTTP Client events id
  27. */
  28. typedef enum {
  29. HTTP_EVENT_ERROR = 0, /*!< This event occurs when there are any errors during execution */
  30. HTTP_EVENT_ON_CONNECTED, /*!< Once the HTTP has been connected to the server, no data exchange has been performed */
  31. HTTP_EVENT_HEADERS_SENT, /*!< After sending all the headers to the server */
  32. HTTP_EVENT_HEADER_SENT = HTTP_EVENT_HEADERS_SENT, /*!< This header has been kept for backward compatability
  33. and will be deprecated in future versions esp-idf */
  34. HTTP_EVENT_ON_HEADER, /*!< Occurs when receiving each header sent from the server */
  35. HTTP_EVENT_ON_DATA, /*!< Occurs when receiving data from the server, possibly multiple portions of the packet */
  36. HTTP_EVENT_ON_FINISH, /*!< Occurs when finish a HTTP session */
  37. HTTP_EVENT_DISCONNECTED, /*!< The connection has been disconnected */
  38. } esp_http_client_event_id_t;
  39. /**
  40. * @brief HTTP Client events data
  41. */
  42. typedef struct esp_http_client_event {
  43. esp_http_client_event_id_t event_id; /*!< event_id, to know the cause of the event */
  44. esp_http_client_handle_t client; /*!< esp_http_client_handle_t context */
  45. void *data; /*!< data of the event */
  46. int data_len; /*!< data length of data */
  47. void *user_data; /*!< user_data context, from esp_http_client_config_t user_data */
  48. char *header_key; /*!< For HTTP_EVENT_ON_HEADER event_id, it's store current http header key */
  49. char *header_value; /*!< For HTTP_EVENT_ON_HEADER event_id, it's store current http header value */
  50. } esp_http_client_event_t;
  51. /**
  52. * @brief HTTP Client transport
  53. */
  54. typedef enum {
  55. HTTP_TRANSPORT_UNKNOWN = 0x0, /*!< Unknown */
  56. HTTP_TRANSPORT_OVER_TCP, /*!< Transport over tcp */
  57. HTTP_TRANSPORT_OVER_SSL, /*!< Transport over ssl */
  58. } esp_http_client_transport_t;
  59. typedef esp_err_t (*http_event_handle_cb)(esp_http_client_event_t *evt);
  60. /**
  61. * @brief HTTP method
  62. */
  63. typedef enum {
  64. HTTP_METHOD_GET = 0, /*!< HTTP GET Method */
  65. HTTP_METHOD_POST, /*!< HTTP POST Method */
  66. HTTP_METHOD_PUT, /*!< HTTP PUT Method */
  67. HTTP_METHOD_PATCH, /*!< HTTP PATCH Method */
  68. HTTP_METHOD_DELETE, /*!< HTTP DELETE Method */
  69. HTTP_METHOD_HEAD, /*!< HTTP HEAD Method */
  70. HTTP_METHOD_NOTIFY, /*!< HTTP NOTIFY Method */
  71. HTTP_METHOD_SUBSCRIBE, /*!< HTTP SUBSCRIBE Method */
  72. HTTP_METHOD_UNSUBSCRIBE,/*!< HTTP UNSUBSCRIBE Method */
  73. HTTP_METHOD_OPTIONS, /*!< HTTP OPTIONS Method */
  74. HTTP_METHOD_COPY, /*!< HTTP COPY Method */
  75. HTTP_METHOD_MOVE, /*!< HTTP MOVE Method */
  76. HTTP_METHOD_LOCK, /*!< HTTP LOCK Method */
  77. HTTP_METHOD_UNLOCK, /*!< HTTP UNLOCK Method */
  78. HTTP_METHOD_PROPFIND, /*!< HTTP PROPFIND Method */
  79. HTTP_METHOD_PROPPATCH, /*!< HTTP PROPPATCH Method */
  80. HTTP_METHOD_MKCOL, /*!< HTTP MKCOL Method */
  81. HTTP_METHOD_MAX,
  82. } esp_http_client_method_t;
  83. /**
  84. * @brief HTTP Authentication type
  85. */
  86. typedef enum {
  87. HTTP_AUTH_TYPE_NONE = 0, /*!< No authention */
  88. HTTP_AUTH_TYPE_BASIC, /*!< HTTP Basic authentication */
  89. HTTP_AUTH_TYPE_DIGEST, /*!< HTTP Disgest authentication */
  90. } esp_http_client_auth_type_t;
  91. /**
  92. * @brief HTTP configuration
  93. */
  94. typedef struct {
  95. const char *url; /*!< HTTP URL, the information on the URL is most important, it overrides the other fields below, if any */
  96. const char *host; /*!< Domain or IP as string */
  97. int port; /*!< Port to connect, default depend on esp_http_client_transport_t (80 or 443) */
  98. const char *username; /*!< Using for Http authentication */
  99. const char *password; /*!< Using for Http authentication */
  100. esp_http_client_auth_type_t auth_type; /*!< Http authentication type, see `esp_http_client_auth_type_t` */
  101. const char *path; /*!< HTTP Path, if not set, default is `/` */
  102. const char *query; /*!< HTTP query */
  103. const char *cert_pem; /*!< SSL server certification, PEM format as string, if the client requires to verify server */
  104. const char *client_cert_pem; /*!< SSL client certification, PEM format as string, if the server requires to verify client */
  105. const char *client_key_pem; /*!< SSL client key, PEM format as string, if the server requires to verify client */
  106. const char *user_agent; /*!< The User Agent string to send with HTTP requests */
  107. esp_http_client_method_t method; /*!< HTTP Method */
  108. int timeout_ms; /*!< Network timeout in milliseconds */
  109. bool disable_auto_redirect; /*!< Disable HTTP automatic redirects */
  110. int max_redirection_count; /*!< Max number of redirections on receiving HTTP redirect status code, using default value if zero*/
  111. int max_authorization_retries; /*!< Max connection retries on receiving HTTP unauthorized status code, using default value if zero. Disables authorization retry if -1*/
  112. http_event_handle_cb event_handler; /*!< HTTP Event Handle */
  113. esp_http_client_transport_t transport_type; /*!< HTTP transport type, see `esp_http_client_transport_t` */
  114. int buffer_size; /*!< HTTP receive buffer size */
  115. int buffer_size_tx; /*!< HTTP transmit buffer size */
  116. void *user_data; /*!< HTTP user_data context */
  117. bool is_async; /*!< Set asynchronous mode, only supported with HTTPS for now */
  118. bool use_global_ca_store; /*!< Use a global ca_store for all the connections in which this bool is set. */
  119. bool skip_cert_common_name_check; /*!< Skip any validation of server certificate CN field */
  120. } esp_http_client_config_t;
  121. /**
  122. * Enum for the HTTP status codes.
  123. */
  124. typedef enum {
  125. /* 2xx - Success */
  126. HttpStatus_Ok = 200,
  127. /* 3xx - Redirection */
  128. HttpStatus_MultipleChoices = 300,
  129. HttpStatus_MovedPermanently = 301,
  130. HttpStatus_Found = 302,
  131. HttpStatus_TemporaryRedirect = 307,
  132. /* 4xx - Client Error */
  133. HttpStatus_Unauthorized = 401,
  134. HttpStatus_Forbidden = 403,
  135. HttpStatus_NotFound = 404,
  136. /* 5xx - Server Error */
  137. HttpStatus_InternalError = 500
  138. } HttpStatus_Code;
  139. #define ESP_ERR_HTTP_BASE (0x7000) /*!< Starting number of HTTP error codes */
  140. #define ESP_ERR_HTTP_MAX_REDIRECT (ESP_ERR_HTTP_BASE + 1) /*!< The error exceeds the number of HTTP redirects */
  141. #define ESP_ERR_HTTP_CONNECT (ESP_ERR_HTTP_BASE + 2) /*!< Error open the HTTP connection */
  142. #define ESP_ERR_HTTP_WRITE_DATA (ESP_ERR_HTTP_BASE + 3) /*!< Error write HTTP data */
  143. #define ESP_ERR_HTTP_FETCH_HEADER (ESP_ERR_HTTP_BASE + 4) /*!< Error read HTTP header from server */
  144. #define ESP_ERR_HTTP_INVALID_TRANSPORT (ESP_ERR_HTTP_BASE + 5) /*!< There are no transport support for the input scheme */
  145. #define ESP_ERR_HTTP_CONNECTING (ESP_ERR_HTTP_BASE + 6) /*!< HTTP connection hasn't been established yet */
  146. #define ESP_ERR_HTTP_EAGAIN (ESP_ERR_HTTP_BASE + 7) /*!< Mapping of errno EAGAIN to esp_err_t */
  147. /**
  148. * @brief Start a HTTP session
  149. * This function must be the first function to call,
  150. * and it returns a esp_http_client_handle_t that you must use as input to other functions in the interface.
  151. * This call MUST have a corresponding call to esp_http_client_cleanup when the operation is complete.
  152. *
  153. * @param[in] config The configurations, see `http_client_config_t`
  154. *
  155. * @return
  156. * - `esp_http_client_handle_t`
  157. * - NULL if any errors
  158. */
  159. esp_http_client_handle_t esp_http_client_init(const esp_http_client_config_t *config);
  160. /**
  161. * @brief Invoke this function after `esp_http_client_init` and all the options calls are made, and will perform the
  162. * transfer as described in the options. It must be called with the same esp_http_client_handle_t as input as the esp_http_client_init call returned.
  163. * esp_http_client_perform performs the entire request in either blocking or non-blocking manner. By default, the API performs request in a blocking manner and returns when done,
  164. * or if it failed, and in non-blocking manner, it returns if EAGAIN/EWOULDBLOCK or EINPROGRESS is encountered, or if it failed. And in case of non-blocking request,
  165. * the user may call this API multiple times unless request & response is complete or there is a failure. To enable non-blocking esp_http_client_perform(), `is_async` member of esp_http_client_config_t
  166. * must be set while making a call to esp_http_client_init() API.
  167. * You can do any amount of calls to esp_http_client_perform while using the same esp_http_client_handle_t. The underlying connection may be kept open if the server allows it.
  168. * If you intend to transfer more than one file, you are even encouraged to do so.
  169. * esp_http_client will then attempt to re-use the same connection for the following transfers, thus making the operations faster, less CPU intense and using less network resources.
  170. * Just note that you will have to use `esp_http_client_set_**` between the invokes to set options for the following esp_http_client_perform.
  171. *
  172. * @note You must never call this function simultaneously from two places using the same client handle.
  173. * Let the function return first before invoking it another time.
  174. * If you want parallel transfers, you must use several esp_http_client_handle_t.
  175. * This function include `esp_http_client_open` -> `esp_http_client_write` -> `esp_http_client_fetch_headers` -> `esp_http_client_read` (and option) `esp_http_client_close`.
  176. *
  177. * @param client The esp_http_client handle
  178. *
  179. * @return
  180. * - ESP_OK on successful
  181. * - ESP_FAIL on error
  182. */
  183. esp_err_t esp_http_client_perform(esp_http_client_handle_t client);
  184. /**
  185. * @brief Set URL for client, when performing this behavior, the options in the URL will replace the old ones
  186. *
  187. * @param[in] client The esp_http_client handle
  188. * @param[in] url The url
  189. *
  190. * @return
  191. * - ESP_OK
  192. * - ESP_FAIL
  193. */
  194. esp_err_t esp_http_client_set_url(esp_http_client_handle_t client, const char *url);
  195. /**
  196. * @brief Set post data, this function must be called before `esp_http_client_perform`.
  197. * Note: The data parameter passed to this function is a pointer and this function will not copy the data
  198. *
  199. * @param[in] client The esp_http_client handle
  200. * @param[in] data post data pointer
  201. * @param[in] len post length
  202. *
  203. * @return
  204. * - ESP_OK
  205. * - ESP_FAIL
  206. */
  207. esp_err_t esp_http_client_set_post_field(esp_http_client_handle_t client, const char *data, int len);
  208. /**
  209. * @brief Get current post field information
  210. *
  211. * @param[in] client The client
  212. * @param[out] data Point to post data pointer
  213. *
  214. * @return Size of post data
  215. */
  216. int esp_http_client_get_post_field(esp_http_client_handle_t client, char **data);
  217. /**
  218. * @brief Set http request header, this function must be called after esp_http_client_init and before any
  219. * perform function
  220. *
  221. * @param[in] client The esp_http_client handle
  222. * @param[in] key The header key
  223. * @param[in] value The header value
  224. *
  225. * @return
  226. * - ESP_OK
  227. * - ESP_FAIL
  228. */
  229. esp_err_t esp_http_client_set_header(esp_http_client_handle_t client, const char *key, const char *value);
  230. /**
  231. * @brief Get http request header.
  232. * The value parameter will be set to NULL if there is no header which is same as
  233. * the key specified, otherwise the address of header value will be assigned to value parameter.
  234. * This function must be called after `esp_http_client_init`.
  235. *
  236. * @param[in] client The esp_http_client handle
  237. * @param[in] key The header key
  238. * @param[out] value The header value
  239. *
  240. * @return
  241. * - ESP_OK
  242. * - ESP_FAIL
  243. */
  244. esp_err_t esp_http_client_get_header(esp_http_client_handle_t client, const char *key, char **value);
  245. /**
  246. * @brief Get http request username.
  247. * The address of username buffer will be assigned to value parameter.
  248. * This function must be called after `esp_http_client_init`.
  249. *
  250. * @param[in] client The esp_http_client handle
  251. * @param[out] value The username value
  252. *
  253. * @return
  254. * - ESP_OK
  255. * - ESP_ERR_INVALID_ARG
  256. */
  257. esp_err_t esp_http_client_get_username(esp_http_client_handle_t client, char **value);
  258. /**
  259. * @brief Set http request username.
  260. * The value of username parameter will be assigned to username buffer.
  261. * If the username parameter is NULL then username buffer will be freed.
  262. *
  263. * @param[in] client The esp_http_client handle
  264. * @param[in] username The username value
  265. *
  266. * @return
  267. * - ESP_OK
  268. * - ESP_ERR_INVALID_ARG
  269. */
  270. esp_err_t esp_http_client_set_username(esp_http_client_handle_t client, const char *username);
  271. /**
  272. * @brief Get http request password.
  273. * The address of password buffer will be assigned to value parameter.
  274. * This function must be called after `esp_http_client_init`.
  275. *
  276. * @param[in] client The esp_http_client handle
  277. * @param[out] value The password value
  278. *
  279. * @return
  280. * - ESP_OK
  281. * - ESP_ERR_INVALID_ARG
  282. */
  283. esp_err_t esp_http_client_get_password(esp_http_client_handle_t client, char **value);
  284. /**
  285. * @brief Set http request password.
  286. * The value of password parameter will be assigned to password buffer.
  287. * If the password parameter is NULL then password buffer will be freed.
  288. *
  289. * @param[in] client The esp_http_client handle
  290. * @param[in] password The password value
  291. *
  292. * @return
  293. * - ESP_OK
  294. * - ESP_ERR_INVALID_ARG
  295. */
  296. esp_err_t esp_http_client_set_password(esp_http_client_handle_t client, char *password);
  297. /**
  298. * @brief Set http request auth_type.
  299. *
  300. * @param[in] client The esp_http_client handle
  301. * @param[in] auth_type The esp_http_client auth type
  302. *
  303. * @return
  304. * - ESP_OK
  305. * - ESP_ERR_INVALID_ARG
  306. */
  307. esp_err_t esp_http_client_set_authtype(esp_http_client_handle_t client, esp_http_client_auth_type_t auth_type);
  308. /**
  309. * @brief Set http request method
  310. *
  311. * @param[in] client The esp_http_client handle
  312. * @param[in] method The method
  313. *
  314. * @return
  315. * - ESP_OK
  316. * - ESP_ERR_INVALID_ARG
  317. */
  318. esp_err_t esp_http_client_set_method(esp_http_client_handle_t client, esp_http_client_method_t method);
  319. /**
  320. * @brief Delete http request header
  321. *
  322. * @param[in] client The esp_http_client handle
  323. * @param[in] key The key
  324. *
  325. * @return
  326. * - ESP_OK
  327. * - ESP_FAIL
  328. */
  329. esp_err_t esp_http_client_delete_header(esp_http_client_handle_t client, const char *key);
  330. /**
  331. * @brief This function will be open the connection, write all header strings and return
  332. *
  333. * @param[in] client The esp_http_client handle
  334. * @param[in] write_len HTTP Content length need to write to the server
  335. *
  336. * @return
  337. * - ESP_OK
  338. * - ESP_FAIL
  339. */
  340. esp_err_t esp_http_client_open(esp_http_client_handle_t client, int write_len);
  341. /**
  342. * @brief This function will write data to the HTTP connection previously opened by esp_http_client_open()
  343. *
  344. * @param[in] client The esp_http_client handle
  345. * @param buffer The buffer
  346. * @param[in] len This value must not be larger than the write_len parameter provided to esp_http_client_open()
  347. *
  348. * @return
  349. * - (-1) if any errors
  350. * - Length of data written
  351. */
  352. int esp_http_client_write(esp_http_client_handle_t client, const char *buffer, int len);
  353. /**
  354. * @brief This function need to call after esp_http_client_open, it will read from http stream, process all receive headers
  355. *
  356. * @param[in] client The esp_http_client handle
  357. *
  358. * @return
  359. * - (0) if stream doesn't contain content-length header, or chunked encoding (checked by `esp_http_client_is_chunked` response)
  360. * - (-1: ESP_FAIL) if any errors
  361. * - Download data length defined by content-length header
  362. */
  363. int esp_http_client_fetch_headers(esp_http_client_handle_t client);
  364. /**
  365. * @brief Check response data is chunked
  366. *
  367. * @param[in] client The esp_http_client handle
  368. *
  369. * @return true or false
  370. */
  371. bool esp_http_client_is_chunked_response(esp_http_client_handle_t client);
  372. /**
  373. * @brief Read data from http stream
  374. *
  375. * @param[in] client The esp_http_client handle
  376. * @param buffer The buffer
  377. * @param[in] len The length
  378. *
  379. * @return
  380. * - (-1) if any errors
  381. * - Length of data was read
  382. */
  383. int esp_http_client_read(esp_http_client_handle_t client, char *buffer, int len);
  384. /**
  385. * @brief Get http response status code, the valid value if this function invoke after `esp_http_client_perform`
  386. *
  387. * @param[in] client The esp_http_client handle
  388. *
  389. * @return Status code
  390. */
  391. int esp_http_client_get_status_code(esp_http_client_handle_t client);
  392. /**
  393. * @brief Get http response content length (from header Content-Length)
  394. * the valid value if this function invoke after `esp_http_client_perform`
  395. *
  396. * @param[in] client The esp_http_client handle
  397. *
  398. * @return
  399. * - (-1) Chunked transfer
  400. * - Content-Length value as bytes
  401. */
  402. int esp_http_client_get_content_length(esp_http_client_handle_t client);
  403. /**
  404. * @brief Close http connection, still kept all http request resources
  405. *
  406. * @param[in] client The esp_http_client handle
  407. *
  408. * @return
  409. * - ESP_OK
  410. * - ESP_FAIL
  411. */
  412. esp_err_t esp_http_client_close(esp_http_client_handle_t client);
  413. /**
  414. * @brief This function must be the last function to call for an session.
  415. * It is the opposite of the esp_http_client_init function and must be called with the same handle as input that a esp_http_client_init call returned.
  416. * This might close all connections this handle has used and possibly has kept open until now.
  417. * Don't call this function if you intend to transfer more files, re-using handles is a key to good performance with esp_http_client.
  418. *
  419. * @param[in] client The esp_http_client handle
  420. *
  421. * @return
  422. * - ESP_OK
  423. * - ESP_FAIL
  424. */
  425. esp_err_t esp_http_client_cleanup(esp_http_client_handle_t client);
  426. /**
  427. * @brief Get transport type
  428. *
  429. * @param[in] client The esp_http_client handle
  430. *
  431. * @return
  432. * - HTTP_TRANSPORT_UNKNOWN
  433. * - HTTP_TRANSPORT_OVER_TCP
  434. * - HTTP_TRANSPORT_OVER_SSL
  435. */
  436. esp_http_client_transport_t esp_http_client_get_transport_type(esp_http_client_handle_t client);
  437. /**
  438. * @brief Set redirection URL.
  439. * When received the 30x code from the server, the client stores the redirect URL provided by the server.
  440. * This function will set the current URL to redirect to enable client to execute the redirection request.
  441. *
  442. * @param[in] client The esp_http_client handle
  443. *
  444. * @return
  445. * - ESP_OK
  446. * - ESP_FAIL
  447. */
  448. esp_err_t esp_http_client_set_redirection(esp_http_client_handle_t client);
  449. /**
  450. * @brief On receiving HTTP Status code 401, this API can be invoked to add authorization
  451. * information.
  452. *
  453. * @note There is a possibility of receiving body message with redirection status codes, thus make sure
  454. * to flush off body data after calling this API.
  455. *
  456. * @param[in] client The esp_http_client handle
  457. */
  458. void esp_http_client_add_auth(esp_http_client_handle_t client);
  459. /**
  460. * @brief Checks if entire data in the response has been read without any error.
  461. *
  462. * @param[in] client The esp_http_client handle
  463. *
  464. * @return
  465. * - true
  466. * - false
  467. */
  468. bool esp_http_client_is_complete_data_received(esp_http_client_handle_t client);
  469. /**
  470. * @brief Helper API to read larger data chunks
  471. * This is a helper API which internally calls `esp_http_client_read` multiple times till the end of data is reached or till the buffer gets full.
  472. *
  473. * @param[in] client The esp_http_client handle
  474. * @param buffer The buffer
  475. * @param[in] len The buffer length
  476. *
  477. * @return
  478. * - Length of data was read
  479. */
  480. int esp_http_client_read_response(esp_http_client_handle_t client, char *buffer, int len);
  481. /**
  482. * @brief Process all remaining response data
  483. * This uses an internal buffer to repeatedly receive, parse, and discard response data until complete data is processed.
  484. * As no additional user-supplied buffer is required, this may be preferrable to `esp_http_client_read_response` in situations where the content of the response may be ignored.
  485. *
  486. * @param[in] client The esp_http_client handle
  487. * @param len Length of data discarded
  488. *
  489. * @return
  490. * - ESP_OK If successful, len will have discarded length
  491. * - ESP_FAIL If failed to read response
  492. * - ESP_ERR_INVALID_ARG If the client is NULL
  493. */
  494. esp_err_t esp_http_client_flush_response(esp_http_client_handle_t client, int *len);
  495. /**
  496. * @brief Get URL from client
  497. *
  498. * @param[in] client The esp_http_client handle
  499. * @param[inout] url The buffer to store URL
  500. * @param[in] len The buffer length
  501. *
  502. * @return
  503. * - ESP_OK
  504. * - ESP_FAIL
  505. */
  506. esp_err_t esp_http_client_get_url(esp_http_client_handle_t client, char *url, const int len);
  507. /**
  508. * @brief Get Chunk-Length from client
  509. *
  510. * @param[in] client The esp_http_client handle
  511. * @param[out] len Variable to store length
  512. *
  513. * @return
  514. * - ESP_OK If successful, len will have length of current chunk
  515. * - ESP_FAIL If the server is not a chunked server
  516. * - ESP_ERR_INVALID_ARG If the client or len are NULL
  517. */
  518. esp_err_t esp_http_client_get_chunk_length(esp_http_client_handle_t client, int *len);
  519. #ifdef __cplusplus
  520. }
  521. #endif
  522. #endif