support post requests and json request options

client/main.c

@@ -6,7 +6,10 @@
 #include <curl/curl.h>
 #include <cjson/cJSON.h>
 
-int write_function(void *data, size_t size, size_t nmemb, void(*data_callback)(char* chunk_ptr, int chunk_size)) {
+typedef void(*DataCallback)(char* chunk_ptr, int chunk_size);
+typedef void(*EndCallback)(int error);
+
+int write_function(void *data, size_t size, size_t nmemb, DataCallback data_callback) {
   long real_size = size * nmemb;
   char* chunk = malloc(real_size);
   memcpy(chunk, data, real_size);
@@ -15,7 +18,7 @@ int write_function(void *data, size_t size, size_t nmemb, void(*data_callback)(c
   return real_size;
 }
 
-void perform_request(const char* url, const char* json_params, void(*data_callback)(char* chunk_ptr, int chunk_size), void(*end_callback)(int error)) {
+void perform_request(const char* url, const char* json_params, DataCallback data_callback, EndCallback end_callback, const char* body, int body_length) {
   printf("downloading %s\n", url);
 
   CURL *http_handle;
@@ -38,13 +41,44 @@ void perform_request(const char* url, const char* json_params, void(*data_callba
   //parse json options
   cJSON* json = cJSON_Parse(json_params);
   cJSON* item = NULL;
+  struct curl_slist* headers_list = NULL;
+
   cJSON_ArrayForEach(item, json) {
     char* key = item->string;
-    printf("%s\n", key);
+
+    if (strcmp(key, "_libcurl_verbose") == 0) {
+      curl_easy_setopt(http_handle, CURLOPT_VERBOSE, 1L);
+    }
+
+    if (strcmp(key, "method") == 0 && cJSON_IsString(item)) {
+      curl_easy_setopt(http_handle, CURLOPT_CUSTOMREQUEST, item->valuestring);
+    }
+    
+    if (strcmp(key, "headers") == 0 && cJSON_IsObject(item)) {
+      cJSON* header = NULL;
+
+      cJSON_ArrayForEach(header, item) {
+        if (!cJSON_IsString(header)) continue;
+        int header_length = strlen(header->string) + strlen(header->valuestring) + 2;
+        char* header_str = malloc(header_length+1);
+        header_str[header_length] = 0;
+
+        sprintf(header_str, "%s: %s", header->string, header->valuestring);
+        headers_list = curl_slist_append(headers_list, header_str);
+        free(header_str);
+      }
+
+      curl_easy_setopt(http_handle, CURLOPT_HTTPHEADER, headers_list);
+    }
   }
   cJSON_Delete(json);
   
- 
+  //add post data if specified
+  if (body != NULL) {
+    curl_easy_setopt(http_handle, CURLOPT_POSTFIELDS, body);
+    curl_easy_setopt(http_handle, CURLOPT_POSTFIELDSIZE, body_length);
+  }
+  
   multi_handle = curl_multi_init();
   curl_multi_add_handle(multi_handle, http_handle);
   
@@ -64,7 +98,8 @@ void perform_request(const char* url, const char* json_params, void(*data_callba
     emscripten_sleep(0);
  
   } while(still_running);
- 
+  
+  curl_slist_free_all(headers_list);
   curl_multi_remove_handle(multi_handle, http_handle);
   curl_easy_cleanup(http_handle);
   curl_multi_cleanup(multi_handle);

client/main.js

@@ -1,13 +1,20 @@
-const cacert_path = "./out/cacert.peem";
+const cacert_path = "./out/cacert.pem";
 const websocket_url = `wss://${location.hostname}/ws`;
 
+function is_str(obj) {
+  return typeof obj === 'string' || obj instanceof String;
+}
+
 function allocate_str(str) {
   return allocate(intArrayFromString(str), ALLOC_NORMAL);
 }
 
+function allocate_array(array) {
+  return allocate(array, ALLOC_NORMAL);
+}
+
 //make emscripten shut up about unsupported syscalls
-function silence_errs() {
-  let is_str = obj => typeof obj === 'string' || obj instanceof String;
+function silence_errs() { 
 
   window._err = window.err;
   window.err = function() {
@@ -29,18 +36,25 @@ function silence_errs() {
 }
 
 //low level interface with c code
-function perform_request(url, params, js_data_callback, js_end_callback) {
+function perform_request(url, params, js_data_callback, js_end_callback, body=null) {
   let params_str = JSON.stringify(params);
   let end_callback_ptr;
   let data_callback_ptr;
   let url_ptr = allocate_str(url);
   let params_ptr = allocate_str(params_str);
 
+  let body_ptr = null;
+  let body_length = 0;
+  if (body) { //assume body is an int8array
+    body_ptr = allocate_array(body);
+    body_length = body.length;
+  }
+
   let end_callback = (error) => {
     Module.removeFunction(end_callback_ptr);
     Module.removeFunction(data_callback_ptr);
+    if (body_ptr) _free(body_ptr);
     _free(url_ptr);
-    _free(params_ptr);
     
     if (error) console.error("request failed with error code "+error);
     js_end_callback(error);
@@ -54,7 +68,8 @@ function perform_request(url, params, js_data_callback, js_end_callback) {
 
   end_callback_ptr = Module.addFunction(end_callback, "vi");
   data_callback_ptr = Module.addFunction(data_callback, "vii");
-  _perform_request(url_ptr, params_ptr, data_callback_ptr, end_callback_ptr);
+  _perform_request(url_ptr, params_ptr, data_callback_ptr, end_callback_ptr, body_ptr, body_length);
+  _free(params_ptr);
 }
 
 function merge_arrays(arrays) {
@@ -69,6 +84,17 @@ function merge_arrays(arrays) {
 }
 
 function libcurl_fetch(url, params={}) {
+  let body = null;
+  if (params.body) {
+    if (is_str(params.body)) {
+      body = new TextEncoder().encode(params.body);
+    }
+    else {
+      body = Uint8Array.from(params);
+    }
+    params.body = true;
+  }
+
   return new Promise((resolve, reject) => {
     let chunks = [];
     let data_callback = (new_data) => {
@@ -79,13 +105,13 @@ function libcurl_fetch(url, params={}) {
       let response_str = new TextDecoder().decode(response_data);
       resolve(response_str);
     }
-    perform_request(url, params, data_callback, finish_callback);  
+    perform_request(url, params, data_callback, finish_callback, body);
   })
 }
 
 async function main() {
   silence_errs();
-  console.log(await libcurl_fetch("https://ifconfig.me/all"));
+  console.log(await libcurl_fetch("https://httpbin.org/anything"));
 }
 
 window.onload = () => {