<p>N A has uploaded this change for <strong>review</strong>.</p><p><a href="https://gerrit.asterisk.org/c/asterisk/+/17663">View Change</a></p><pre style="font-family: monospace,monospace; white-space: pre-wrap;">func_json: Adds JSON_DECODE function<br><br>Adds the JSON_DECODE function for parsing JSON in the<br>dialplan. JSON parsing already exists in the Asterisk<br>core and is used for many different things. This<br>function exposes the basic parsing capability to<br>the user in the dialplan, for instance, in conjunction<br>with CURL for using API responses.<br><br>ASTERISK-29706 #close<br><br>Change-Id: Iea60c49a7358dfdc2db60803cdc9a742f808ba2c<br>---<br>A doc/CHANGES-staging/func_json.txt<br>A funcs/func_json.c<br>2 files changed, 233 insertions(+), 0 deletions(-)<br><br></pre><pre style="font-family: monospace,monospace; white-space: pre-wrap;">git pull ssh://gerrit.asterisk.org:29418/asterisk refs/changes/63/17663/1</pre><pre style="font-family: monospace,monospace; white-space: pre-wrap;"><span>diff --git a/doc/CHANGES-staging/func_json.txt b/doc/CHANGES-staging/func_json.txt</span><br><span>new file mode 100644</span><br><span>index 0000000..79bb2da</span><br><span>--- /dev/null</span><br><span>+++ b/doc/CHANGES-staging/func_json.txt</span><br><span>@@ -0,0 +1,5 @@</span><br><span style="color: hsl(120, 100%, 40%);">+Subject: func_json</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+The JSON_DECODE dialplan function can now be used</span><br><span style="color: hsl(120, 100%, 40%);">+to parse JSON strings, such as in conjunction with</span><br><span style="color: hsl(120, 100%, 40%);">+CURL for using API responses.</span><br><span>diff --git a/funcs/func_json.c b/funcs/func_json.c</span><br><span>new file mode 100644</span><br><span>index 0000000..a48b85c</span><br><span>--- /dev/null</span><br><span>+++ b/funcs/func_json.c</span><br><span>@@ -0,0 +1,228 @@</span><br><span style="color: hsl(120, 100%, 40%);">+/*</span><br><span style="color: hsl(120, 100%, 40%);">+ * Asterisk -- An open source telephony toolkit.</span><br><span style="color: hsl(120, 100%, 40%);">+ *</span><br><span style="color: hsl(120, 100%, 40%);">+ * Copyright (C) 2021, Naveen Albert</span><br><span style="color: hsl(120, 100%, 40%);">+ *</span><br><span style="color: hsl(120, 100%, 40%);">+ * See http://www.asterisk.org for more information about</span><br><span style="color: hsl(120, 100%, 40%);">+ * the Asterisk project. Please do not directly contact</span><br><span style="color: hsl(120, 100%, 40%);">+ * any of the maintainers of this project for assistance;</span><br><span style="color: hsl(120, 100%, 40%);">+ * the project provides a web site, mailing lists and IRC</span><br><span style="color: hsl(120, 100%, 40%);">+ * channels for your use.</span><br><span style="color: hsl(120, 100%, 40%);">+ *</span><br><span style="color: hsl(120, 100%, 40%);">+ * This program is free software, distributed under the terms of</span><br><span style="color: hsl(120, 100%, 40%);">+ * the GNU General Public License Version 2. See the LICENSE file</span><br><span style="color: hsl(120, 100%, 40%);">+ * at the top of the source tree.</span><br><span style="color: hsl(120, 100%, 40%);">+ */</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+/*! \file</span><br><span style="color: hsl(120, 100%, 40%);">+ *</span><br><span style="color: hsl(120, 100%, 40%);">+ * \brief JSON parsing function</span><br><span style="color: hsl(120, 100%, 40%);">+ *</span><br><span style="color: hsl(120, 100%, 40%);">+ * \author Naveen Albert <asterisk@phreaknet.org></span><br><span style="color: hsl(120, 100%, 40%);">+ *</span><br><span style="color: hsl(120, 100%, 40%);">+ * \ingroup functions</span><br><span style="color: hsl(120, 100%, 40%);">+ */</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+/*** MODULEINFO</span><br><span style="color: hsl(120, 100%, 40%);">+ <support_level>extended</support_level></span><br><span style="color: hsl(120, 100%, 40%);">+ ***/</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+#include "asterisk.h"</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+#include "asterisk/module.h"</span><br><span style="color: hsl(120, 100%, 40%);">+#include "asterisk/channel.h"</span><br><span style="color: hsl(120, 100%, 40%);">+#include "asterisk/pbx.h"</span><br><span style="color: hsl(120, 100%, 40%);">+#include "asterisk/utils.h"</span><br><span style="color: hsl(120, 100%, 40%);">+#include "asterisk/test.h"</span><br><span style="color: hsl(120, 100%, 40%);">+#include "asterisk/app.h"</span><br><span style="color: hsl(120, 100%, 40%);">+#include "asterisk/conversions.h"</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+/*** DOCUMENTATION</span><br><span style="color: hsl(120, 100%, 40%);">+ <function name="JSON_DECODE" language="en_US"></span><br><span style="color: hsl(120, 100%, 40%);">+ <synopsis></span><br><span style="color: hsl(120, 100%, 40%);">+ Returns the string value of a JSON object key from a string containing a</span><br><span style="color: hsl(120, 100%, 40%);">+ JSON array.</span><br><span style="color: hsl(120, 100%, 40%);">+ </synopsis></span><br><span style="color: hsl(120, 100%, 40%);">+ <syntax></span><br><span style="color: hsl(120, 100%, 40%);">+ <parameter name="varname" required="true"></span><br><span style="color: hsl(120, 100%, 40%);">+ <para>The name of the variable containing the JSON string to parse.</para></span><br><span style="color: hsl(120, 100%, 40%);">+ </parameter></span><br><span style="color: hsl(120, 100%, 40%);">+ <parameter name="item" required="true"></span><br><span style="color: hsl(120, 100%, 40%);">+ <para>The name of the key whose value to return.</para></span><br><span style="color: hsl(120, 100%, 40%);">+ </parameter></span><br><span style="color: hsl(120, 100%, 40%);">+ </syntax></span><br><span style="color: hsl(120, 100%, 40%);">+ <description></span><br><span style="color: hsl(120, 100%, 40%);">+ <para>The JSON_DECODE function retrieves the value of the given variable name</span><br><span style="color: hsl(120, 100%, 40%);">+ and parses it as JSON, returning the value at a specified key. If the key cannot</span><br><span style="color: hsl(120, 100%, 40%);">+ be found, an empty string is returned.</para></span><br><span style="color: hsl(120, 100%, 40%);">+ </description></span><br><span style="color: hsl(120, 100%, 40%);">+ <see-also></span><br><span style="color: hsl(120, 100%, 40%);">+ <ref type="function">CURL</ref></span><br><span style="color: hsl(120, 100%, 40%);">+ </see-also></span><br><span style="color: hsl(120, 100%, 40%);">+ </function></span><br><span style="color: hsl(120, 100%, 40%);">+ ***/</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+AST_THREADSTORAGE(result_buf);</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+static int json_decode_read(struct ast_channel *chan, const char *cmd, char *data, char *buf, size_t len)</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ struct ast_json *json, *jsonval;</span><br><span style="color: hsl(120, 100%, 40%);">+ AST_DECLARE_APP_ARGS(args,</span><br><span style="color: hsl(120, 100%, 40%);">+ AST_APP_ARG(varname);</span><br><span style="color: hsl(120, 100%, 40%);">+ AST_APP_ARG(key);</span><br><span style="color: hsl(120, 100%, 40%);">+ );</span><br><span style="color: hsl(120, 100%, 40%);">+ char *varsubst, *result2;</span><br><span style="color: hsl(120, 100%, 40%);">+ const char *result = NULL;</span><br><span style="color: hsl(120, 100%, 40%);">+ struct ast_str *str = ast_str_thread_get(&result_buf, 16);</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ AST_STANDARD_APP_ARGS(args, data);</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ if (ast_strlen_zero(args.varname)) {</span><br><span style="color: hsl(120, 100%, 40%);">+ ast_log(LOG_WARNING, "%s requires a variable name\n", cmd);</span><br><span style="color: hsl(120, 100%, 40%);">+ return -1;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+ if (ast_strlen_zero(args.key)) {</span><br><span style="color: hsl(120, 100%, 40%);">+ ast_log(LOG_WARNING, "%s requires a key\n", cmd);</span><br><span style="color: hsl(120, 100%, 40%);">+ return -1;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ varsubst = ast_alloca(strlen(args.varname) + 4); /* +4 for ${} and null terminator */</span><br><span style="color: hsl(120, 100%, 40%);">+ if (!varsubst) {</span><br><span style="color: hsl(120, 100%, 40%);">+ ast_log(LOG_ERROR, "Failed to allocate string\n");</span><br><span style="color: hsl(120, 100%, 40%);">+ return -1;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+ sprintf(varsubst, "${%s}", args.varname); /* safe, because of the above allocation */</span><br><span style="color: hsl(120, 100%, 40%);">+ ast_str_substitute_variables(&str, 0, chan, varsubst);</span><br><span style="color: hsl(120, 100%, 40%);">+ if (ast_str_strlen(str) == 0) {</span><br><span style="color: hsl(120, 100%, 40%);">+ ast_debug(1, "Variable '%s' contains no data, nothing to search!\n", args.varname);</span><br><span style="color: hsl(120, 100%, 40%);">+ return -1; /* empty json string */</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ ast_debug(1, "Parsing JSON: %s\n", ast_str_buffer(str));</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ json = ast_json_load_str(str, NULL);</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ if (!json) {</span><br><span style="color: hsl(120, 100%, 40%);">+ ast_log(LOG_WARNING, "Failed to parse as JSON: %s\n", ast_str_buffer(str));</span><br><span style="color: hsl(120, 100%, 40%);">+ return -1;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ jsonval = ast_json_object_get(json, args.key);</span><br><span style="color: hsl(120, 100%, 40%);">+ if (!jsonval) { /* no error or warning should be thrown */</span><br><span style="color: hsl(120, 100%, 40%);">+ ast_debug(1, "Could not find key '%s' in parsed JSON\n", args.key);</span><br><span style="color: hsl(120, 100%, 40%);">+ ast_json_free(json);</span><br><span style="color: hsl(120, 100%, 40%);">+ return -1;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+ switch(ast_json_typeof(jsonval)) {</span><br><span style="color: hsl(120, 100%, 40%);">+ int r;</span><br><span style="color: hsl(120, 100%, 40%);">+ case AST_JSON_STRING:</span><br><span style="color: hsl(120, 100%, 40%);">+ result = ast_json_string_get(jsonval);</span><br><span style="color: hsl(120, 100%, 40%);">+ snprintf(buf, len, "%s", result);</span><br><span style="color: hsl(120, 100%, 40%);">+ break;</span><br><span style="color: hsl(120, 100%, 40%);">+ case AST_JSON_INTEGER:</span><br><span style="color: hsl(120, 100%, 40%);">+ r = ast_json_integer_get(jsonval);</span><br><span style="color: hsl(120, 100%, 40%);">+ snprintf(buf, len, "%d", r); /* the snprintf below is mutually exclusive with this one */</span><br><span style="color: hsl(120, 100%, 40%);">+ break;</span><br><span style="color: hsl(120, 100%, 40%);">+ default:</span><br><span style="color: hsl(120, 100%, 40%);">+ result2 = ast_json_dump_string(jsonval);</span><br><span style="color: hsl(120, 100%, 40%);">+ snprintf(buf, len, "%s", result2);</span><br><span style="color: hsl(120, 100%, 40%);">+ ast_json_free(result2);</span><br><span style="color: hsl(120, 100%, 40%);">+ break;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+ ast_json_free(json);</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ return 0;</span><br><span style="color: hsl(120, 100%, 40%);">+}</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+static struct ast_custom_function json_decode_function = {</span><br><span style="color: hsl(120, 100%, 40%);">+ .name = "JSON_DECODE",</span><br><span style="color: hsl(120, 100%, 40%);">+ .read = json_decode_read,</span><br><span style="color: hsl(120, 100%, 40%);">+};</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+#ifdef TEST_FRAMEWORK</span><br><span style="color: hsl(120, 100%, 40%);">+AST_TEST_DEFINE(test_JSON_DECODE)</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ int i, res = AST_TEST_PASS;</span><br><span style="color: hsl(120, 100%, 40%);">+ struct ast_channel *chan; /* dummy channel */</span><br><span style="color: hsl(120, 100%, 40%);">+ struct ast_str *str; /* fancy string for holding comparing value */</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ const char *test_strings[][5] = {</span><br><span style="color: hsl(120, 100%, 40%);">+ {"{\"city\": \"Anytown\", \"state\": \"USA\"}", "city", "Anytown"},</span><br><span style="color: hsl(120, 100%, 40%);">+ {"{\"city\": \"Anytown\", \"state\": \"USA\"}", "state", "USA"},</span><br><span style="color: hsl(120, 100%, 40%);">+ {"{\"city\": \"Anytown\", \"state\": \"USA\"}", "blah", ""},</span><br><span style="color: hsl(120, 100%, 40%);">+ {"{\"key1\": \"123\", \"key2\": \"456\"}", "key1", "123"},</span><br><span style="color: hsl(120, 100%, 40%);">+ {"{\"key1\": 123, \"key2\": 456}", "key1", "123"},</span><br><span style="color: hsl(120, 100%, 40%);">+ };</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ switch (cmd) {</span><br><span style="color: hsl(120, 100%, 40%);">+ case TEST_INIT:</span><br><span style="color: hsl(120, 100%, 40%);">+ info->name = "func_JSON_DECODE";</span><br><span style="color: hsl(120, 100%, 40%);">+ info->category = "/funcs/func_json/";</span><br><span style="color: hsl(120, 100%, 40%);">+ info->summary = "Test JSON_DECODE function";</span><br><span style="color: hsl(120, 100%, 40%);">+ info->description = "Verify JSON_DECODE behavior";</span><br><span style="color: hsl(120, 100%, 40%);">+ return AST_TEST_NOT_RUN;</span><br><span style="color: hsl(120, 100%, 40%);">+ case TEST_EXECUTE:</span><br><span style="color: hsl(120, 100%, 40%);">+ break;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ if (!(chan = ast_dummy_channel_alloc())) {</span><br><span style="color: hsl(120, 100%, 40%);">+ ast_test_status_update(test, "Unable to allocate dummy channel\n");</span><br><span style="color: hsl(120, 100%, 40%);">+ return AST_TEST_FAIL;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ if (!(str = ast_str_create(64))) {</span><br><span style="color: hsl(120, 100%, 40%);">+ ast_test_status_update(test, "Unable to allocate dynamic string buffer\n");</span><br><span style="color: hsl(120, 100%, 40%);">+ ast_channel_release(chan);</span><br><span style="color: hsl(120, 100%, 40%);">+ return AST_TEST_FAIL;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ for (i = 0; i < ARRAY_LEN(test_strings); i++) {</span><br><span style="color: hsl(120, 100%, 40%);">+ char tmp[512], tmp2[512] = "";</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ struct ast_var_t *var = ast_var_assign("test_string", test_strings[i][0]);</span><br><span style="color: hsl(120, 100%, 40%);">+ if (!var) {</span><br><span style="color: hsl(120, 100%, 40%);">+ ast_test_status_update(test, "Unable to allocate variable\n");</span><br><span style="color: hsl(120, 100%, 40%);">+ ast_free(str);</span><br><span style="color: hsl(120, 100%, 40%);">+ ast_channel_release(chan);</span><br><span style="color: hsl(120, 100%, 40%);">+ return AST_TEST_FAIL;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ AST_LIST_INSERT_HEAD(ast_channel_varshead(chan), var, entries);</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ snprintf(tmp, sizeof(tmp), "${JSON_DECODE(%s,%s)}", "test_string", test_strings[i][1]);</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ ast_str_substitute_variables(&str, 0, chan, tmp);</span><br><span style="color: hsl(120, 100%, 40%);">+ if (strcmp(test_strings[i][2], ast_str_buffer(str))) {</span><br><span style="color: hsl(120, 100%, 40%);">+ ast_test_status_update(test, "Format string '%s' substituted to '%s'. Expected '%s'.\n", test_strings[i][0], tmp2, test_strings[i][2]);</span><br><span style="color: hsl(120, 100%, 40%);">+ res = AST_TEST_FAIL;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ ast_free(str);</span><br><span style="color: hsl(120, 100%, 40%);">+ ast_channel_release(chan);</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ return res;</span><br><span style="color: hsl(120, 100%, 40%);">+}</span><br><span style="color: hsl(120, 100%, 40%);">+#endif</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+static int unload_module(void)</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ int res;</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ AST_TEST_UNREGISTER(test_JSON_DECODE);</span><br><span style="color: hsl(120, 100%, 40%);">+ res = ast_custom_function_unregister(&json_decode_function);</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ return res;</span><br><span style="color: hsl(120, 100%, 40%);">+}</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+static int load_module(void)</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ int res;</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ AST_TEST_REGISTER(test_JSON_DECODE);</span><br><span style="color: hsl(120, 100%, 40%);">+ res = ast_custom_function_register(&json_decode_function);</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ return res;</span><br><span style="color: hsl(120, 100%, 40%);">+}</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+AST_MODULE_INFO_STANDARD_EXTENDED(ASTERISK_GPL_KEY, "JSON decoding function");</span><br><span></span><br></pre><p>To view, visit <a href="https://gerrit.asterisk.org/c/asterisk/+/17663">change 17663</a>. To unsubscribe, or for help writing mail filters, visit <a href="https://gerrit.asterisk.org/settings">settings</a>.</p><div itemscope itemtype="http://schema.org/EmailMessage"><div itemscope itemprop="action" itemtype="http://schema.org/ViewAction"><link itemprop="url" href="https://gerrit.asterisk.org/c/asterisk/+/17663"/><meta itemprop="name" content="View Change"/></div></div>
<div style="display:none"> Gerrit-Project: asterisk </div>
<div style="display:none"> Gerrit-Branch: 19 </div>
<div style="display:none"> Gerrit-Change-Id: Iea60c49a7358dfdc2db60803cdc9a742f808ba2c </div>
<div style="display:none"> Gerrit-Change-Number: 17663 </div>
<div style="display:none"> Gerrit-PatchSet: 1 </div>
<div style="display:none"> Gerrit-Owner: N A <mail@interlinked.x10host.com> </div>
<div style="display:none"> Gerrit-MessageType: newchange </div>