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@adymitruk
Last active October 23, 2023 20:19
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Trello in CQRS/ES in fish shell
#set up the dir structure if it doesn't exist
set t ~/.trello; mkdir -p $t
function if_exist # we don't want to litter our code with ifs if a read model or events are not there yet. Return /dev/nul for empty
if test -e $t/$argv[1]; echo $t/$argv[1]; else; echo /dev/null; end
end
function list # provide lists from our tab delimited entries with filtering and line item numbers to make choices
set list $argv[1]; set column_to_show $argv[2]; set filter $argv[3]; set count 1
cat (if_exist $list) | grep -e "$filter\$" | while read line
set -l line_items (string split \t $line)
echo $count\) $line_items[$column_to_show]
set count (math $count + 1)
end
end
function lookup_id # grab ids by looking up values in event stream or read models
set list $argv[1]; set filter $argv[2]; set list_num $argv[3]
set line_items (grep "$filter\$" $t/$list | sed $list_num"q;d" | string split \t)[1]
echo $line_items[1]
end
function show_board # our example of a screen that uses a read model
paste ( begin; echo Todo:; list rm_items 2 todo; end | psub) ( begin; echo Done:; list rm_items 2 done; end | psub) | sed 's/\t/ \t/' | column -s \t -t | while read line
if not set -q not_first_anymore
set_color cyan; echo $line; set_color normal
else
echo $line
end
set not_first_anymore 1
end
set -e not_first_anymore
end
while true
clear
set_color green; echo Trello App\n; set_color normal
show_board
echo; read -P "(C)reate (F)inish (Q)uit: " choice
set event
switch $choice # our source of issuing commands
case Q or q; break;
case C or c; read -P 'Task name: ' name; set -g event (date +%s)\t"TaskCreated"\t"$name"
case F or f; read -P 'Finish item: ' item;
set -g event (date +%s)\t"TaskFinished"\t(lookup_id rm_items todo $item);
end
if test -n $event
echo $event >> $t/events # append our event stream
set event_type (echo $event | string split \t)[2]; set event_id (echo $event | string split \t)[1];
switch $event_type # our "pub sub"
case TaskCreated; echo (string replace TaskCreated\t '' $event)\ttodo >> $t/rm_items; # we only have one read model in this one
case TaskFinished; set items (string split \t $event); set id $items[3]; echo id: $id; sed -i "s/\($id.*\)todo/\\1done/" $t/rm_items;
end
end
end
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