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-rw-r--r--src/json-extension-functions.cc915
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diff --git a/src/json-extension-functions.cc b/src/json-extension-functions.cc
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+++ b/src/json-extension-functions.cc
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+/**
+ * Copyright (c) 2014, Timothy Stack
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ * * Neither the name of Timothy Stack nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ''AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * @file json-extension-functions.cc
+ */
+
+#include <cstring>
+#include <string>
+
+#include "config.h"
+#include "mapbox/variant.hpp"
+#include "scn/scn.h"
+#include "sqlite-extension-func.hh"
+#include "sqlite3.h"
+#include "vtab_module.hh"
+#include "vtab_module_json.hh"
+#include "yajl/api/yajl_gen.h"
+#include "yajlpp/json_op.hh"
+#include "yajlpp/yajlpp.hh"
+
+using namespace mapbox;
+
+#define JSON_SUBTYPE 74 /* Ascii for "J" */
+
+class sql_json_op : public json_op {
+public:
+ explicit sql_json_op(json_ptr& ptr) : json_op(ptr){};
+
+ int sjo_type{-1};
+ std::string sjo_str;
+ int64_t sjo_int{0};
+ double sjo_float{0.0};
+};
+
+static void
+null_or_default(sqlite3_context* context, int argc, sqlite3_value* argv[])
+{
+ if (argc > 2) {
+ sqlite3_result_value(context, argv[2]);
+ } else {
+ sqlite3_result_null(context);
+ }
+}
+
+struct contains_userdata {
+ util::variant<string_fragment, sqlite3_int64, bool> cu_match_value{false};
+ size_t cu_depth{0};
+ bool cu_result{false};
+};
+
+static int
+contains_string(void* ctx, const unsigned char* str, size_t len)
+{
+ auto sf = string_fragment::from_bytes(str, len);
+ auto& cu = *((contains_userdata*) ctx);
+
+ if (cu.cu_depth <= 1 && cu.cu_match_value.get<string_fragment>() == sf) {
+ cu.cu_result = true;
+ }
+
+ return 1;
+}
+
+static int
+contains_integer(void* ctx, long long value)
+{
+ auto& cu = *((contains_userdata*) ctx);
+
+ if (cu.cu_depth <= 1 && cu.cu_match_value.get<sqlite3_int64>() == value) {
+ cu.cu_result = true;
+ }
+
+ return 1;
+}
+
+static int
+contains_null(void* ctx)
+{
+ auto& cu = *((contains_userdata*) ctx);
+
+ cu.cu_result = true;
+
+ return 1;
+}
+
+static bool
+json_contains(vtab_types::nullable<const char> nullable_json_in,
+ sqlite3_value* value)
+{
+ if (nullable_json_in.n_value == nullptr
+ || nullable_json_in.n_value[0] == '\0')
+ {
+ return false;
+ }
+
+ const auto* json_in = nullable_json_in.n_value;
+ auto_mem<yajl_handle_t> handle(yajl_free);
+ yajl_callbacks cb;
+ contains_userdata cu;
+
+ memset(&cb, 0, sizeof(cb));
+ handle = yajl_alloc(&cb, nullptr, &cu);
+
+ cb.yajl_start_array = +[](void* ctx) {
+ auto& cu = *((contains_userdata*) ctx);
+
+ cu.cu_depth += 1;
+
+ return 1;
+ };
+ cb.yajl_end_array = +[](void* ctx) {
+ auto& cu = *((contains_userdata*) ctx);
+
+ cu.cu_depth -= 1;
+
+ return 1;
+ };
+ cb.yajl_start_map = +[](void* ctx) {
+ auto& cu = *((contains_userdata*) ctx);
+
+ cu.cu_depth += 2;
+
+ return 1;
+ };
+ cb.yajl_end_map = +[](void* ctx) {
+ auto& cu = *((contains_userdata*) ctx);
+
+ cu.cu_depth -= 2;
+
+ return 1;
+ };
+
+ switch (sqlite3_value_type(value)) {
+ case SQLITE3_TEXT:
+ cb.yajl_string = contains_string;
+ cu.cu_match_value = string_fragment::from_bytes(
+ sqlite3_value_text(value), sqlite3_value_bytes(value));
+ break;
+ case SQLITE_INTEGER:
+ cb.yajl_integer = contains_integer;
+ cu.cu_match_value = sqlite3_value_int64(value);
+ break;
+ case SQLITE_NULL:
+ cb.yajl_null = contains_null;
+ break;
+ }
+
+ if (yajl_parse(handle.in(), (const unsigned char*) json_in, strlen(json_in))
+ != yajl_status_ok
+ || yajl_complete_parse(handle.in()) != yajl_status_ok)
+ {
+ throw yajlpp_error(handle.in(), json_in, strlen(json_in));
+ }
+
+ return cu.cu_result;
+}
+
+static int
+gen_handle_null(void* ctx)
+{
+ sql_json_op* sjo = (sql_json_op*) ctx;
+ yajl_gen gen = (yajl_gen) sjo->jo_ptr_data;
+
+ if (sjo->jo_ptr.jp_state == json_ptr::match_state_t::DONE) {
+ sjo->sjo_type = SQLITE_NULL;
+ } else {
+ sjo->jo_ptr_error_code = yajl_gen_null(gen);
+ }
+
+ return sjo->jo_ptr_error_code == yajl_gen_status_ok;
+}
+
+static int
+gen_handle_boolean(void* ctx, int boolVal)
+{
+ sql_json_op* sjo = (sql_json_op*) ctx;
+ yajl_gen gen = (yajl_gen) sjo->jo_ptr_data;
+
+ if (sjo->jo_ptr.jp_state == json_ptr::match_state_t::DONE) {
+ sjo->sjo_type = SQLITE_INTEGER;
+ sjo->sjo_int = boolVal;
+ } else {
+ sjo->jo_ptr_error_code = yajl_gen_bool(gen, boolVal);
+ }
+
+ return sjo->jo_ptr_error_code == yajl_gen_status_ok;
+}
+
+static int
+gen_handle_string(void* ctx, const unsigned char* stringVal, size_t len)
+{
+ sql_json_op* sjo = (sql_json_op*) ctx;
+ yajl_gen gen = (yajl_gen) sjo->jo_ptr_data;
+
+ if (sjo->jo_ptr.jp_state == json_ptr::match_state_t::DONE) {
+ sjo->sjo_type = SQLITE3_TEXT;
+ sjo->sjo_str = std::string((char*) stringVal, len);
+ } else {
+ sjo->jo_ptr_error_code = yajl_gen_string(gen, stringVal, len);
+ }
+
+ return sjo->jo_ptr_error_code == yajl_gen_status_ok;
+}
+
+static int
+gen_handle_number(void* ctx, const char* numval, size_t numlen)
+{
+ sql_json_op* sjo = (sql_json_op*) ctx;
+ yajl_gen gen = (yajl_gen) sjo->jo_ptr_data;
+
+ if (sjo->jo_ptr.jp_state == json_ptr::match_state_t::DONE) {
+ auto num_sv = scn::string_view{numval, numlen};
+ auto scan_int_res = scn::scan_value<int64_t>(num_sv);
+
+ if (scan_int_res && scan_int_res.empty()) {
+ sjo->sjo_int = scan_int_res.value();
+ sjo->sjo_type = SQLITE_INTEGER;
+ } else {
+ auto scan_float_res = scn::scan_value<double>(num_sv);
+
+ sjo->sjo_float = scan_float_res.value();
+ sjo->sjo_type = SQLITE_FLOAT;
+ }
+ } else {
+ sjo->jo_ptr_error_code = yajl_gen_number(gen, numval, numlen);
+ }
+
+ return sjo->jo_ptr_error_code == yajl_gen_status_ok;
+}
+
+static void
+sql_jget(sqlite3_context* context, int argc, sqlite3_value** argv)
+{
+ if (argc < 2) {
+ sqlite3_result_error(context, "expecting JSON value and pointer", -1);
+ return;
+ }
+
+ if (sqlite3_value_type(argv[0]) == SQLITE_NULL) {
+ null_or_default(context, argc, argv);
+ return;
+ }
+
+ const char* json_in = (const char*) sqlite3_value_text(argv[0]);
+
+ if (sqlite3_value_type(argv[1]) == SQLITE_NULL) {
+ sqlite3_result_text(context, json_in, -1, SQLITE_TRANSIENT);
+ return;
+ }
+
+ const char* ptr_in = (const char*) sqlite3_value_text(argv[1]);
+ json_ptr jp(ptr_in);
+ sql_json_op jo(jp);
+ auto_mem<yajl_handle_t> handle(yajl_free);
+ unsigned char* err;
+ yajlpp_gen gen;
+
+ yajl_gen_config(gen, yajl_gen_beautify, false);
+
+ jo.jo_ptr_callbacks = json_op::gen_callbacks;
+ jo.jo_ptr_callbacks.yajl_null = gen_handle_null;
+ jo.jo_ptr_callbacks.yajl_boolean = gen_handle_boolean;
+ jo.jo_ptr_callbacks.yajl_string = gen_handle_string;
+ jo.jo_ptr_callbacks.yajl_number = gen_handle_number;
+ jo.jo_ptr_data = gen.get_handle();
+
+ handle.reset(yajl_alloc(&json_op::ptr_callbacks, nullptr, &jo));
+ switch (yajl_parse(
+ handle.in(), (const unsigned char*) json_in, strlen(json_in)))
+ {
+ case yajl_status_error: {
+ err = yajl_get_error(handle.in(),
+ 1,
+ (const unsigned char*) json_in,
+ strlen(json_in));
+ sqlite3_result_error(context, (const char*) err, -1);
+ yajl_free_error(handle.in(), err);
+ return;
+ }
+ case yajl_status_client_canceled:
+ if (jo.jo_ptr.jp_state
+ == json_ptr::match_state_t::ERR_INVALID_ESCAPE)
+ {
+ sqlite3_result_error(
+ context, jo.jo_ptr.error_msg().c_str(), -1);
+ } else {
+ null_or_default(context, argc, argv);
+ }
+ return;
+ default:
+ break;
+ }
+
+ switch (yajl_complete_parse(handle.in())) {
+ case yajl_status_error: {
+ err = yajl_get_error(handle.in(),
+ 1,
+ (const unsigned char*) json_in,
+ strlen(json_in));
+ sqlite3_result_error(context, (const char*) err, -1);
+ yajl_free_error(handle.in(), err);
+ return;
+ }
+ case yajl_status_client_canceled:
+ if (jo.jo_ptr.jp_state
+ == json_ptr::match_state_t::ERR_INVALID_ESCAPE)
+ {
+ sqlite3_result_error(
+ context, jo.jo_ptr.error_msg().c_str(), -1);
+ } else {
+ null_or_default(context, argc, argv);
+ }
+ return;
+ default:
+ break;
+ }
+
+ switch (jo.sjo_type) {
+ case SQLITE3_TEXT:
+ sqlite3_result_text(context,
+ jo.sjo_str.c_str(),
+ jo.sjo_str.size(),
+ SQLITE_TRANSIENT);
+ return;
+ case SQLITE_NULL:
+ sqlite3_result_null(context);
+ return;
+ case SQLITE_INTEGER:
+ sqlite3_result_int(context, jo.sjo_int);
+ return;
+ case SQLITE_FLOAT:
+ sqlite3_result_double(context, jo.sjo_float);
+ return;
+ }
+
+ string_fragment result = gen.to_string_fragment();
+
+ if (result.empty()) {
+ null_or_default(context, argc, argv);
+ return;
+ }
+
+ sqlite3_result_text(
+ context, result.data(), result.length(), SQLITE_TRANSIENT);
+#ifdef HAVE_SQLITE3_VALUE_SUBTYPE
+ sqlite3_result_subtype(context, JSON_SUBTYPE);
+#endif
+}
+
+struct concat_context {
+ concat_context(yajl_gen gen_handle) : cc_gen_handle(gen_handle) {}
+
+ yajl_gen cc_gen_handle;
+ int cc_depth{0};
+};
+
+static int
+concat_gen_null(void* ctx)
+{
+ auto* cc = static_cast<concat_context*>(ctx);
+
+ if (cc->cc_depth > 0) {
+ return yajl_gen_null(cc->cc_gen_handle) == yajl_gen_status_ok;
+ }
+
+ return 1;
+}
+
+static int
+concat_gen_boolean(void* ctx, int val)
+{
+ auto* cc = static_cast<concat_context*>(ctx);
+
+ return yajl_gen_bool(cc->cc_gen_handle, val) == yajl_gen_status_ok;
+}
+
+static int
+concat_gen_number(void* ctx, const char* val, size_t len)
+{
+ auto* cc = static_cast<concat_context*>(ctx);
+
+ return yajl_gen_number(cc->cc_gen_handle, val, len) == yajl_gen_status_ok;
+}
+
+static int
+concat_gen_string(void* ctx, const unsigned char* val, size_t len)
+{
+ auto* cc = static_cast<concat_context*>(ctx);
+
+ return yajl_gen_string(cc->cc_gen_handle, val, len) == yajl_gen_status_ok;
+}
+
+static int
+concat_gen_start_map(void* ctx)
+{
+ auto* cc = static_cast<concat_context*>(ctx);
+
+ cc->cc_depth += 1;
+ return yajl_gen_map_open(cc->cc_gen_handle) == yajl_gen_status_ok;
+}
+
+static int
+concat_gen_end_map(void* ctx)
+{
+ auto* cc = static_cast<concat_context*>(ctx);
+
+ cc->cc_depth -= 1;
+ return yajl_gen_map_close(cc->cc_gen_handle) == yajl_gen_status_ok;
+}
+
+static int
+concat_gen_map_key(void* ctx, const unsigned char* key, size_t len)
+{
+ auto* cc = static_cast<concat_context*>(ctx);
+
+ return yajl_gen_string(cc->cc_gen_handle, key, len) == yajl_gen_status_ok;
+}
+
+static int
+concat_gen_start_array(void* ctx)
+{
+ auto* cc = static_cast<concat_context*>(ctx);
+
+ cc->cc_depth += 1;
+ if (cc->cc_depth == 1) {
+ return 1;
+ }
+ return yajl_gen_array_open(cc->cc_gen_handle) == yajl_gen_status_ok;
+}
+
+static int
+concat_gen_end_array(void* ctx)
+{
+ auto* cc = static_cast<concat_context*>(ctx);
+
+ cc->cc_depth -= 1;
+ if (cc->cc_depth == 0) {
+ return 1;
+ }
+ return yajl_gen_array_close(cc->cc_gen_handle) == yajl_gen_status_ok;
+}
+
+static void
+concat_gen_elements(yajl_gen gen, const unsigned char* text, size_t len)
+{
+ auto_mem<yajl_handle_t> handle(yajl_free);
+ yajl_callbacks callbacks = {nullptr};
+ concat_context cc{gen};
+
+ callbacks.yajl_null = concat_gen_null;
+ callbacks.yajl_boolean = concat_gen_boolean;
+ callbacks.yajl_number = concat_gen_number;
+ callbacks.yajl_string = concat_gen_string;
+ callbacks.yajl_start_map = concat_gen_start_map;
+ callbacks.yajl_end_map = concat_gen_end_map;
+ callbacks.yajl_map_key = concat_gen_map_key;
+ callbacks.yajl_start_array = concat_gen_start_array;
+ callbacks.yajl_end_array = concat_gen_end_array;
+
+ handle = yajl_alloc(&callbacks, nullptr, &cc);
+ yajl_config(handle, yajl_allow_comments, 1);
+ if (yajl_parse(handle, (const unsigned char*) text, len) != yajl_status_ok
+ || yajl_complete_parse(handle) != yajl_status_ok)
+ {
+ std::unique_ptr<unsigned char, decltype(&free)> err_msg(
+ yajl_get_error(handle, 1, (const unsigned char*) text, len), free);
+
+ throw sqlite_func_error("Invalid JSON: {}",
+ (const char*) err_msg.get());
+ }
+}
+
+static json_string
+json_concat(nonstd::optional<const char*> json_in,
+ const std::vector<sqlite3_value*>& values)
+{
+ yajlpp_gen gen;
+
+ yajl_gen_config(gen, yajl_gen_beautify, false);
+
+ {
+ yajlpp_array array(gen);
+
+ if (json_in) {
+ concat_gen_elements(gen,
+ (const unsigned char*) json_in.value(),
+ strlen(json_in.value()));
+ }
+
+ for (auto* const val : values) {
+ switch (sqlite3_value_type(val)) {
+ case SQLITE_NULL:
+ array.gen();
+ break;
+ case SQLITE_INTEGER:
+ array.gen(sqlite3_value_int64(val));
+ break;
+ case SQLITE_FLOAT:
+ array.gen(sqlite3_value_double(val));
+ break;
+ case SQLITE3_TEXT: {
+ const auto* text_val = sqlite3_value_text(val);
+
+ if (sqlite3_value_subtype(val) == JSON_SUBTYPE) {
+ concat_gen_elements(
+ gen, text_val, strlen((const char*) text_val));
+ } else {
+ array.gen((const char*) text_val);
+ }
+ break;
+ }
+ }
+ }
+ }
+
+ return json_string(gen);
+}
+
+#if 0
+static flattened_json_string
+sql_flatten_json_object(string_fragment sf)
+{
+ yajlpp_gen gen;
+
+ {
+ json_ptr jp("/");
+ json_op jo(jp);
+ auto_mem<yajl_handle_t> handle(yajl_free);
+
+ jo.jo_ptr_data = gen.get_handle();
+ yajl_gen_config(gen, yajl_gen_beautify, false);
+ handle.reset(yajl_alloc(&json_op::gen_callbacks, nullptr, &jo));
+ switch (yajl_parse(
+ handle.in(), (const unsigned char*) sf.data(), sf.length())) {
+ case yajl_status_error:
+ case yajl_status_client_canceled:
+ throw yajlpp_error(handle.in(), sf.data(), sf.length());
+ case yajl_status_ok:
+ break;
+ }
+ switch (yajl_complete_parse(handle.in())) {
+ case yajl_status_error:
+ case yajl_status_client_canceled:
+ throw yajlpp_error(handle.in(), sf.data(), sf.length());
+ case yajl_status_ok:
+ break;
+ }
+ }
+
+ auto result = gen.to_string_fragment();
+ if (!result.startswith("{") || !result.endswith("}")) {
+ throw std::runtime_error(
+ "flatten_json_object() requires a JSON object");
+ }
+
+ return flattened_json_string(gen);
+}
+#endif
+
+struct json_agg_context {
+ yajl_gen_t* jac_yajl_gen;
+};
+
+static void
+sql_json_group_object_step(sqlite3_context* context,
+ int argc,
+ sqlite3_value** argv)
+{
+ if ((argc % 2) == 1) {
+ sqlite3_result_error(
+ context,
+ "Uneven number of arguments to json_group_object(), "
+ "expecting key and value pairs",
+ -1);
+ return;
+ }
+
+ json_agg_context* jac = (json_agg_context*) sqlite3_aggregate_context(
+ context, sizeof(json_agg_context));
+
+ if (jac->jac_yajl_gen == nullptr) {
+ jac->jac_yajl_gen = yajl_gen_alloc(nullptr);
+ yajl_gen_config(jac->jac_yajl_gen, yajl_gen_beautify, false);
+
+ yajl_gen_map_open(jac->jac_yajl_gen);
+ }
+
+ for (int lpc = 0; (lpc + 1) < argc; lpc += 2) {
+ if (sqlite3_value_type(argv[lpc]) == SQLITE_NULL) {
+ continue;
+ }
+
+ const unsigned char* key = sqlite3_value_text(argv[lpc]);
+
+ yajl_gen_string(jac->jac_yajl_gen, key, strlen((const char*) key));
+
+ switch (sqlite3_value_type(argv[lpc + 1])) {
+ case SQLITE_NULL:
+ yajl_gen_null(jac->jac_yajl_gen);
+ break;
+ case SQLITE3_TEXT: {
+ const unsigned char* value = sqlite3_value_text(argv[lpc + 1]);
+#ifdef HAVE_SQLITE3_VALUE_SUBTYPE
+ int subtype = sqlite3_value_subtype(argv[lpc + 1]);
+
+ if (subtype == JSON_SUBTYPE) {
+ yajl_gen_number(jac->jac_yajl_gen,
+ (const char*) value,
+ strlen((const char*) value));
+ } else {
+#endif
+ yajl_gen_string(
+ jac->jac_yajl_gen, value, strlen((const char*) value));
+#ifdef HAVE_SQLITE3_VALUE_SUBTYPE
+ }
+#endif
+ break;
+ }
+ case SQLITE_INTEGER: {
+ const unsigned char* value = sqlite3_value_text(argv[lpc + 1]);
+
+ yajl_gen_number(jac->jac_yajl_gen,
+ (const char*) value,
+ strlen((const char*) value));
+ break;
+ }
+ case SQLITE_FLOAT: {
+ double value = sqlite3_value_double(argv[lpc + 1]);
+
+ yajl_gen_double(jac->jac_yajl_gen, value);
+ break;
+ }
+ }
+ }
+}
+
+static void
+sql_json_group_object_final(sqlite3_context* context)
+{
+ json_agg_context* jac
+ = (json_agg_context*) sqlite3_aggregate_context(context, 0);
+
+ if (jac == nullptr) {
+ sqlite3_result_text(context, "{}", -1, SQLITE_STATIC);
+ } else {
+ const unsigned char* buf;
+ size_t len;
+
+ yajl_gen_map_close(jac->jac_yajl_gen);
+ yajl_gen_get_buf(jac->jac_yajl_gen, &buf, &len);
+ sqlite3_result_text(context, (const char*) buf, len, SQLITE_TRANSIENT);
+#ifdef HAVE_SQLITE3_VALUE_SUBTYPE
+ sqlite3_result_subtype(context, JSON_SUBTYPE);
+#endif
+ yajl_gen_free(jac->jac_yajl_gen);
+ }
+}
+
+static void
+sql_json_group_array_step(sqlite3_context* context,
+ int argc,
+ sqlite3_value** argv)
+{
+ json_agg_context* jac = (json_agg_context*) sqlite3_aggregate_context(
+ context, sizeof(json_agg_context));
+
+ if (jac->jac_yajl_gen == nullptr) {
+ jac->jac_yajl_gen = yajl_gen_alloc(nullptr);
+ yajl_gen_config(jac->jac_yajl_gen, yajl_gen_beautify, false);
+
+ yajl_gen_array_open(jac->jac_yajl_gen);
+ }
+
+ for (int lpc = 0; lpc < argc; lpc++) {
+ switch (sqlite3_value_type(argv[lpc])) {
+ case SQLITE_NULL:
+ yajl_gen_null(jac->jac_yajl_gen);
+ break;
+ case SQLITE3_TEXT: {
+ const unsigned char* value = sqlite3_value_text(argv[lpc]);
+#ifdef HAVE_SQLITE3_VALUE_SUBTYPE
+ int subtype = sqlite3_value_subtype(argv[lpc]);
+
+ if (subtype == JSON_SUBTYPE) {
+ yajl_gen_number(jac->jac_yajl_gen,
+ (const char*) value,
+ strlen((const char*) value));
+ } else {
+#endif
+ yajl_gen_string(
+ jac->jac_yajl_gen, value, strlen((const char*) value));
+#ifdef HAVE_SQLITE3_VALUE_SUBTYPE
+ }
+#endif
+ break;
+ }
+ case SQLITE_INTEGER: {
+ const unsigned char* value = sqlite3_value_text(argv[lpc]);
+
+ yajl_gen_number(jac->jac_yajl_gen,
+ (const char*) value,
+ strlen((const char*) value));
+ break;
+ }
+ case SQLITE_FLOAT: {
+ double value = sqlite3_value_double(argv[lpc]);
+
+ yajl_gen_double(jac->jac_yajl_gen, value);
+ break;
+ }
+ }
+ }
+}
+
+static void
+sql_json_group_array_final(sqlite3_context* context)
+{
+ json_agg_context* jac
+ = (json_agg_context*) sqlite3_aggregate_context(context, 0);
+
+ if (jac == nullptr) {
+ sqlite3_result_text(context, "[]", -1, SQLITE_STATIC);
+ } else {
+ const unsigned char* buf;
+ size_t len;
+
+ yajl_gen_array_close(jac->jac_yajl_gen);
+ yajl_gen_get_buf(jac->jac_yajl_gen, &buf, &len);
+ sqlite3_result_text(context, (const char*) buf, len, SQLITE_TRANSIENT);
+#ifdef HAVE_SQLITE3_VALUE_SUBTYPE
+ sqlite3_result_subtype(context, JSON_SUBTYPE);
+#endif
+ yajl_gen_free(jac->jac_yajl_gen);
+ }
+}
+
+int
+json_extension_functions(struct FuncDef** basic_funcs,
+ struct FuncDefAgg** agg_funcs)
+{
+ static struct FuncDef json_funcs[] = {
+ sqlite_func_adapter<decltype(&json_concat), json_concat>::builder(
+ help_text("json_concat",
+ "Returns an array with the given values concatenated "
+ "onto the end. "
+ "If the initial value is null, the result will be an "
+ "array with "
+ "the given elements. If the initial value is an array, "
+ "the result "
+ "will be an array with the given values at the end. If "
+ "the initial "
+ "value is not null or an array, the result will be an "
+ "array with "
+ "two elements: the initial value and the given value.")
+ .sql_function()
+ .with_parameter({"json", "The initial JSON value."})
+ .with_parameter(
+ help_text("value",
+ "The value(s) to add to the end of the array.")
+ .one_or_more())
+ .with_tags({"json"})
+ .with_example({
+ "To append the number 4 to null",
+ "SELECT json_concat(NULL, 4)",
+ })
+ .with_example({
+ "To append 4 and 5 to the array [1, 2, 3]",
+ "SELECT json_concat('[1, 2, 3]', 4, 5)",
+ })
+ .with_example({
+ "To concatenate two arrays together",
+ "SELECT json_concat('[1, 2, 3]', json('[4, 5]'))",
+ })),
+
+ sqlite_func_adapter<decltype(&json_contains), json_contains>::builder(
+ help_text("json_contains",
+ "Check if a JSON value contains the given element.")
+ .sql_function()
+ .with_parameter({"json", "The JSON value to query."})
+ .with_parameter(
+ {"value", "The value to look for in the first argument"})
+ .with_tags({"json"})
+ .with_example({
+ "To test if a JSON array contains the number 4",
+ "SELECT json_contains('[1, 2, 3]', 4)",
+ })
+ .with_example({
+ "To test if a JSON array contains the string 'def'",
+ "SELECT json_contains('[\"abc\", \"def\"]', 'def')",
+ })),
+
+ {
+ "jget",
+ -1,
+ SQLITE_UTF8,
+ 0,
+ sql_jget,
+ help_text("jget",
+ "Get the value from a JSON object using a JSON-Pointer.")
+ .sql_function()
+ .with_parameter({"json", "The JSON object to query."})
+ .with_parameter(
+ {"ptr", "The JSON-Pointer to lookup in the object."})
+ .with_parameter(
+ help_text("default",
+ "The default value if the value was not found")
+ .optional())
+ .with_tags({"json"})
+ .with_example(
+ {"To get the root of a JSON value", "SELECT jget('1', '')"})
+ .with_example({
+ "To get the property named 'b' in a JSON object",
+ "SELECT jget('{ \"a\": 1, \"b\": 2 }', '/b')",
+ })
+ .with_example({
+ "To get the 'msg' property and return a default if "
+ "it does not exist",
+ "SELECT jget(null, '/msg', 'Hello')",
+ }),
+ },
+
+#if 0
+ sqlite_func_adapter<decltype(&sql_flatten_json_object),
+ sql_flatten_json_object>::
+ builder(help_text("flatten_json_object", "hello")
+ .sql_function()
+ .with_parameter({"json", "The JSON"})),
+#endif
+
+ {nullptr},
+ };
+
+ static struct FuncDefAgg json_agg_funcs[] = {
+ {
+ "json_group_object",
+ -1,
+ 0,
+ sql_json_group_object_step,
+ sql_json_group_object_final,
+ help_text("json_group_object")
+ .sql_function()
+ .with_summary(
+ "Collect the given values from a query into a JSON object")
+ .with_parameter(
+ help_text("name", "The property name for the value"))
+ .with_parameter(
+ help_text("value", "The value to add to the object")
+ .one_or_more())
+ .with_tags({"json"})
+ .with_example({"To create an object from arguments",
+ "SELECT json_group_object('a', 1, 'b', 2)"})
+ .with_example({
+ "To create an object from a pair of columns",
+ "SELECT json_group_object(column1, column2) FROM "
+ "(VALUES ('a', 1), ('b', 2))",
+ }),
+ },
+ {
+ "json_group_array",
+ -1,
+ 0,
+ sql_json_group_array_step,
+ sql_json_group_array_final,
+ help_text("json_group_array")
+ .sql_function()
+ .with_summary(
+ "Collect the given values from a query into a JSON array")
+ .with_parameter(
+ help_text("value", "The values to append to the array")
+ .one_or_more())
+ .with_tags({"json"})
+ .with_example({
+ "To create an array from arguments",
+ "SELECT json_group_array('one', 2, 3.4)",
+ })
+ .with_example({
+ "To create an array from a column of values",
+ "SELECT json_group_array(column1) FROM (VALUES "
+ "(1), (2), (3))",
+ }),
+ },
+
+ {nullptr},
+ };
+
+ *basic_funcs = json_funcs;
+ *agg_funcs = json_agg_funcs;
+
+ return SQLITE_OK;
+}