arpadboda commented on a change in pull request #499: MINIFICPP-748 - Nanofi: add custom C processor example URL: https://github.com/apache/nifi-minifi-cpp/pull/499#discussion_r265514199
########## File path: nanofi/examples/hash_file.c ########## @@ -0,0 +1,121 @@ +/* + * 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 + * + * http://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. +*/ + +#ifdef OPENSSL_SUPPORT + +#include "api/nanofi.h" +#include <openssl/md5.h> +#include <unistd.h> +#include <stdlib.h> +#include <stdio.h> +#include <string.h> +#include <sys/stat.h> + +void custom_processor_logic(processor_session * ps, processor_context * ctx) { + flow_file_record * ffr = get(ps, ctx); + if(ffr == NULL) { + return; + } + uint8_t * buffer = (uint8_t*)malloc(ffr->size* sizeof(uint8_t)); + + get_content(ffr, buffer, ffr->size); + + + MD5_CTX context; + MD5_Init(&context); + MD5_Update(&context, buffer, ffr->size); + + free(buffer); + + unsigned char digest[MD5_DIGEST_LENGTH]; + MD5_Final(digest, &context); + + char md5string[33]; + for(int i = 0; i < 16; ++i) { + sprintf(&md5string[i*2], "%02x", (unsigned int)digest[i]); + } + + char prop_value[50]; + + if(get_property(ctx, "checksum_attr_name", prop_value, 50) != 0) { + return; // Attr name not found + } + + add_attribute(ffr, prop_value, (void*)md5string, strlen(md5string)); + + transfer_to_relationship(ffr, ps, SUCCESS_RELATIONSHIP); + + free_flowfile(ffr); +} + +int main(int argc, char **argv) { + + if (argc < 2) { + printf("Error: must run ./hash_file <file>\n"); + exit(1); + } + + char *file = argv[1]; + + if(access( file, F_OK ) == -1) { + printf("Error: %s doesn't exist!\n", file); + exit(1); + } + + struct stat stats; + stat(file, &stats); + + // Check for file existence + if (S_ISDIR(stats.st_mode)){ + printf("Error: %s is a directory!\n", file); + exit(1); + } + + add_custom_processor("md5proc", custom_processor_logic); + + standalone_processor *standalone_proc = create_processor("md5proc"); + + const char * checksum_attr_name = "md5attr"; + + set_standalone_property(standalone_proc, "checksum_attr_name", checksum_attr_name); + + + flow_file_record * ffr = create_flowfile(file, strlen(file)); + + flow_file_record * new_ff = invoke_ff(standalone_proc, ffr); + + free_flowfile(ffr); + + attribute attr; + attr.key = checksum_attr_name; + attr.value_size = 0; + get_attribute(new_ff, &attr); + + char md5value[50]; + + snprintf(md5value, attr.value_size, "%s", (const char*)attr.value+1); Review comment: Just found this: https://issues.apache.org/jira/browse/MINIFICPP-646 This might fit. However my question was mostly about timing: this is most probably going to be a breaking change in the API and 0.6.0 is to be released soon, I wonder if we try to add it or do it later in 0.7.0 or 1.0? The later we do it the more we break. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected] With regards, Apache Git Services
