streamlet-examples/hash
branchv_0
changeset 45 f466b4c7d9b1
parent 34 0b9e4af08cc8
child 49 ab48ad4ecb91
equal deleted inserted replaced
44:dc5c210295d0 45:f466b4c7d9b1
       
     1 #!/bin/bash
       
     2 
       
     3 # Relational pipes
       
     4 # Copyright © 2020 František Kučera (Frantovo.cz, GlobalCode.info)
       
     5 #
       
     6 # This program is free software: you can redistribute it and/or modify
       
     7 # it under the terms of the GNU General Public License as published by
       
     8 # the Free Software Foundation, version 3 of the License.
       
     9 #
       
    10 # This program is distributed in the hope that it will be useful,
       
    11 # but WITHOUT ANY WARRANTY; without even the implied warranty of
       
    12 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
       
    13 # GNU General Public License for more details.
       
    14 #
       
    15 # You should have received a copy of the GNU General Public License
       
    16 # along with this program. If not, see <http://www.gnu.org/licenses/>.
       
    17 
       
    18 
       
    19 # This streamlet computes hashes of given files.
       
    20 # Default algorithm is sha256.
       
    21 #
       
    22 # Any supported hash algorithm can be specified by e.g. --option "attribute" "sha512"
       
    23 # The hash command is derived from the algorithm name by adding "sum" suffix and must be available at $PATH.
       
    24 #
       
    25 # Multiple algorithms can be specified (just repeat the --option).
       
    26 # But single streamlet instance will run them sequentially.
       
    27 # When parallell processing is needed (usually faster) then multiple scriptlet instances should be used:
       
    28 #   --scriptlet hash --option "sha1" --as "sha1" --scriptlet hash --option "sha256" --as "sha256"
       
    29 # instead of:
       
    30 #   --scriptlet hash --option "sha1" --as "sha1" --option "sha256" --as "sha256"
       
    31 
       
    32 
       
    33 . "$(dirname $0)/streamlet-common.sh"
       
    34 
       
    35 processMessage_WAITING_FOR_OUTPUT_ATTRIBUTES_METADATA() {
       
    36 	hashTypes=()
       
    37 	hashCommands=()
       
    38 
       
    39 	for (( i=0; i<${#optionNames[@]}; i++)); do
       
    40 		if [[ "x${optionNames[$i]}" == "xattribute" ]]; then
       
    41 			if type "${optionValues[$i]}sum" > /dev/null; then
       
    42 				hashTypes+=("${optionValues[$i]}");
       
    43 				hashCommands+=("${optionValues[$i]}sum");
       
    44 			else
       
    45 				echo "Unsupported attribute: ${optionValues[$i]}" >&2
       
    46 			fi
       
    47 		else
       
    48 			echo "Unsupported option: ${optionNames[$i]}" >&2
       
    49 		fi
       
    50 	done
       
    51 
       
    52 	if [[ -z "$hashTypes" ]]; then
       
    53 		hashTypes=("sha256")
       
    54 		hashCommands=("sha256sum")
       
    55 	fi
       
    56 
       
    57 	for (( i=0; i<${#hashTypes[@]}; i++)); do
       
    58 		send OUTPUT_ATTRIBUTE_METADATA "${outputAttributeAliases[$i]-${hashTypes[$i]}}"    "string"
       
    59 	done
       
    60 
       
    61 	send WAITING_FOR_INPUT_ATTRIBUTES
       
    62 }
       
    63 
       
    64 processMessage_WAITING_FOR_OUTPUT_ATTRIBUTES() {
       
    65 	for (( i=0; i<${#hashTypes[@]}; i++)); do
       
    66 		value=$("${hashCommands[$i]}" "$currentFile" | cut -d" " -f1) 2>/dev/null;
       
    67 		if [[ -z "$value" ]]; then isNull="true"; else isNull="false"; fi
       
    68 		send OUTPUT_ATTRIBUTE "$value"    "$isNull";
       
    69 	done
       
    70 	
       
    71 	send WAITING_FOR_INPUT_ATTRIBUTES;
       
    72 }
       
    73 
       
    74 initialize
       
    75 processMessages