mirror of
https://github.com/ivabus/pantry
synced 2024-11-30 04:05:06 +03:00
0371d6dd5a
new file: projects/apache.org/avro/quickstop.c
238 lines
No EOL
7.2 KiB
C
238 lines
No EOL
7.2 KiB
C
/*
|
|
* Licensed to the Apache Software Foundation (ASF) under one or more
|
|
* contributor license agreements. See the NOTICE file distributed with
|
|
* this work for additional information regarding copyright ownership.
|
|
* The ASF licenses this file to you under the Apache License, Version 2.0
|
|
* (the "License"); you may not use this file except in compliance with
|
|
* the License. You may obtain a copy of the License at
|
|
*
|
|
* https://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
|
|
* implied. See the License for the specific language governing
|
|
* permissions and limitations under the License.
|
|
*/
|
|
|
|
#include <avro.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
|
|
#ifdef DEFLATE_CODEC
|
|
#define QUICKSTOP_CODEC "deflate"
|
|
#else
|
|
#define QUICKSTOP_CODEC "null"
|
|
#endif
|
|
|
|
avro_schema_t person_schema;
|
|
int64_t id = 0;
|
|
|
|
/* A simple schema for our tutorial */
|
|
const char PERSON_SCHEMA[] =
|
|
"{\"type\":\"record\",\
|
|
\"name\":\"Person\",\
|
|
\"fields\":[\
|
|
{\"name\": \"ID\", \"type\": \"long\"},\
|
|
{\"name\": \"First\", \"type\": \"string\"},\
|
|
{\"name\": \"Last\", \"type\": \"string\"},\
|
|
{\"name\": \"Phone\", \"type\": \"string\"},\
|
|
{\"name\": \"Age\", \"type\": \"int\"}]}";
|
|
|
|
/* Parse schema into a schema data structure */
|
|
void init_schema(void)
|
|
{
|
|
if (avro_schema_from_json_literal(PERSON_SCHEMA, &person_schema)) {
|
|
fprintf(stderr, "Unable to parse person schema\n");
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
}
|
|
|
|
/* Create a value to match the person schema and save it */
|
|
void
|
|
add_person(avro_file_writer_t db, const char *first, const char *last,
|
|
const char *phone, int32_t age)
|
|
{
|
|
avro_value_iface_t *person_class =
|
|
avro_generic_class_from_schema(person_schema);
|
|
|
|
avro_value_t person;
|
|
avro_generic_value_new(person_class, &person);
|
|
|
|
avro_value_t id_value;
|
|
avro_value_t first_value;
|
|
avro_value_t last_value;
|
|
avro_value_t age_value;
|
|
avro_value_t phone_value;
|
|
|
|
if (avro_value_get_by_name(&person, "ID", &id_value, NULL) == 0) {
|
|
avro_value_set_long(&id_value, ++id);
|
|
}
|
|
if (avro_value_get_by_name(&person, "First", &first_value, NULL) == 0) {
|
|
avro_value_set_string(&first_value, first);
|
|
}
|
|
if (avro_value_get_by_name(&person, "Last", &last_value, NULL) == 0) {
|
|
avro_value_set_string(&last_value, last);
|
|
}
|
|
if (avro_value_get_by_name(&person, "Age", &age_value, NULL) == 0) {
|
|
avro_value_set_int(&age_value, age);
|
|
}
|
|
if (avro_value_get_by_name(&person, "Phone", &phone_value, NULL) == 0) {
|
|
avro_value_set_string(&phone_value, phone);
|
|
}
|
|
|
|
if (avro_file_writer_append_value(db, &person)) {
|
|
fprintf(stderr,
|
|
"Unable to write Person value to memory buffer\nMessage: %s\n", avro_strerror());
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
|
|
/* Decrement all our references to prevent memory from leaking */
|
|
avro_value_decref(&person);
|
|
avro_value_iface_decref(person_class);
|
|
}
|
|
|
|
int print_person(avro_file_reader_t db, avro_schema_t reader_schema)
|
|
{
|
|
|
|
avro_value_iface_t *person_class =
|
|
avro_generic_class_from_schema(person_schema);
|
|
|
|
avro_value_t person;
|
|
avro_generic_value_new(person_class, &person);
|
|
|
|
int rval;
|
|
|
|
rval = avro_file_reader_read_value(db, &person);
|
|
if (rval == 0) {
|
|
int64_t id;
|
|
int32_t age;
|
|
int32_t *p;
|
|
size_t size;
|
|
avro_value_t id_value;
|
|
avro_value_t first_value;
|
|
avro_value_t last_value;
|
|
avro_value_t age_value;
|
|
avro_value_t phone_value;
|
|
|
|
if (avro_value_get_by_name(&person, "ID", &id_value, NULL) == 0) {
|
|
avro_value_get_long(&id_value, &id);
|
|
fprintf(stdout, "%"PRId64" | ", id);
|
|
}
|
|
if (avro_value_get_by_name(&person, "First", &first_value, NULL) == 0) {
|
|
avro_value_get_string(&first_value, &p, &size);
|
|
fprintf(stdout, "%15s | ", p);
|
|
}
|
|
if (avro_value_get_by_name(&person, "Last", &last_value, NULL) == 0) {
|
|
avro_value_get_string(&last_value, &p, &size);
|
|
fprintf(stdout, "%15s | ", p);
|
|
}
|
|
if (avro_value_get_by_name(&person, "Phone", &phone_value, NULL) == 0) {
|
|
avro_value_get_string(&phone_value, &p, &size);
|
|
fprintf(stdout, "%15s | ", p);
|
|
}
|
|
if (avro_value_get_by_name(&person, "Age", &age_value, NULL) == 0) {
|
|
avro_value_get_int(&age_value, &age);
|
|
fprintf(stdout, "%"PRId32" | ", age);
|
|
}
|
|
fprintf(stdout, "\n");
|
|
|
|
/* We no longer need this memory */
|
|
avro_value_decref(&person);
|
|
avro_value_iface_decref(person_class);
|
|
}
|
|
return rval;
|
|
}
|
|
|
|
int main(void)
|
|
{
|
|
int rval;
|
|
avro_file_reader_t dbreader;
|
|
avro_file_writer_t db;
|
|
avro_schema_t projection_schema, first_name_schema, phone_schema;
|
|
int64_t i;
|
|
const char *dbname = "quickstop.db";
|
|
char number[15] = {0};
|
|
|
|
/* Initialize the schema structure from JSON */
|
|
init_schema();
|
|
|
|
/* Delete the database if it exists */
|
|
remove(dbname);
|
|
/* Create a new database */
|
|
rval = avro_file_writer_create_with_codec
|
|
(dbname, person_schema, &db, QUICKSTOP_CODEC, 0);
|
|
if (rval) {
|
|
fprintf(stderr, "There was an error creating %s\n", dbname);
|
|
fprintf(stderr, " error message: %s\n", avro_strerror());
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
|
|
/* Add lots of people to the database */
|
|
for (i = 0; i < 1000; i++)
|
|
{
|
|
sprintf(number, "(%d)", (int)i);
|
|
add_person(db, "Dante", "Hicks", number, 32);
|
|
add_person(db, "Randal", "Graves", "(555) 123-5678", 30);
|
|
add_person(db, "Veronica", "Loughran", "(555) 123-0987", 28);
|
|
add_person(db, "Caitlin", "Bree", "(555) 123-2323", 27);
|
|
add_person(db, "Bob", "Silent", "(555) 123-6422", 29);
|
|
add_person(db, "Jay", "???", number, 26);
|
|
}
|
|
|
|
/* Close the block and open a new one */
|
|
avro_file_writer_flush(db);
|
|
add_person(db, "Super", "Man", "123456", 31);
|
|
|
|
avro_file_writer_close(db);
|
|
|
|
fprintf(stdout, "\nNow let's read all the records back out\n");
|
|
|
|
/* Read all the records and print them */
|
|
if (avro_file_reader(dbname, &dbreader)) {
|
|
fprintf(stderr, "Error opening file: %s\n", avro_strerror());
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
for (i = 0; i < id; i++) {
|
|
if (print_person(dbreader, NULL)) {
|
|
fprintf(stderr, "Error printing person\nMessage: %s\n", avro_strerror());
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
}
|
|
avro_file_reader_close(dbreader);
|
|
|
|
/* You can also use projection, to only decode only the data you are
|
|
interested in. This is particularly useful when you have
|
|
huge data sets and you'll only interest in particular fields
|
|
e.g. your contacts First name and phone number */
|
|
projection_schema = avro_schema_record("Person", NULL);
|
|
first_name_schema = avro_schema_string();
|
|
phone_schema = avro_schema_string();
|
|
avro_schema_record_field_append(projection_schema, "First",
|
|
first_name_schema);
|
|
avro_schema_record_field_append(projection_schema, "Phone",
|
|
phone_schema);
|
|
|
|
/* Read only the record you're interested in */
|
|
fprintf(stdout,
|
|
"\n\nUse projection to print only the First name and phone numbers\n");
|
|
if (avro_file_reader(dbname, &dbreader)) {
|
|
fprintf(stderr, "Error opening file: %s\n", avro_strerror());
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
for (i = 0; i < id; i++) {
|
|
if (print_person(dbreader, projection_schema)) {
|
|
fprintf(stderr, "Error printing person: %s\n",
|
|
avro_strerror());
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
}
|
|
avro_file_reader_close(dbreader);
|
|
avro_schema_decref(first_name_schema);
|
|
avro_schema_decref(phone_schema);
|
|
avro_schema_decref(projection_schema);
|
|
|
|
/* We don't need this schema anymore */
|
|
avro_schema_decref(person_schema);
|
|
return 0;
|
|
} |