cohost image uploader

upchost.sh

#!/usr/bin/env zsh
# cohost image uploader v3
# requirements: linux + zsh + imagemagick + curl + jq
#               (you don’t need to be a zsh user)
# limitations: does not actually attach the image to the post
set -euo pipefail
if [ $# -lt 3 ]; then
    >&2 echo "usage: $0 <projectHandle> <postId> <file> [file ...]"
    exit 1
fi

if [ "${COHOST_COOKIE+x}" = "" ]; then
    >&2 echo 'COHOST_COOKIE not set!'
    >&2 echo 'to avoid this prompt next time: read -r COHOST_COOKIE; export COHOST_COOKIE'
    >&2 printf \%s 'paste your cohost cookie (connect.sid=... with % encoding): '
    read -r COHOST_COOKIE
fi
case "$COHOST_COOKIE" in
    (connect.sid=*) COHOST_COOKIE="$COHOST_COOKIE" ;;
    (*) COHOST_COOKIE="connect.sid=$COHOST_COOKIE" ;;
esac
projectHandle=$1; shift
postId=$1; shift
json=$(mktemp)

for file; do
    basename -- "$file" | read -r basename
    file --mime-type "$file" | sed 's/.*: //' | read -r contentType
    stat -c \%s -- "$file" | read -r contentLength  # FIXME doesn’t work on bsd
    identify "$file" | sed -E 's/.* ([^ ]+)( [^ ]+){6}/\1/;s/x/ /' | read -r width height

    >&2 echo "step 1/3 (posts.attachment.start)"
    curl -fsSo "$json" 'https://cohost.org/api/v1/trpc/posts.attachment.start?batch=1' \
        -X POST -H 'Content-Type: application/json' -H "Cookie: $COHOST_COOKIE" --data-raw \
        '{"0":{"projectHandle":"'"$projectHandle"'","postId":'"$postId"',"filename":"'"$basename"'","contentType":"'"$contentType"'","contentLength":'"$contentLength"',"width":'"$width"',"height":'"$height"'}}'

    # build list of -F key=value arguments from what we were given in step 1
    set --
    < "$json" jq -r '.[0].result.data.requiredFields | to_entries[] | "\(.key)=\(.value)"' | while read -r kv; do
        set -- "$@" -F "$kv"
    done

    >&2 echo "step 2/3 (redcent-dev)"
    curl -fsS "$@" -F "file=@$file" "$(< "$json" jq -r '.[0].result.data.url')"

    >&2 echo "step 3/3 (posts.attachment.finish)"
    curl -fsSo "$json" 'https://cohost.org/api/v1/trpc/posts.attachment.finish?batch=1' \
        -X POST -H 'Content-Type: application/json' -H "Cookie: $COHOST_COOKIE" --data-raw \
        '{"0":{"projectHandle":"'"$projectHandle"'","postId":'"$postId"',"attachmentId":"'"$(< "$json" jq -r '.[0].result.data.attachmentId')"'"}}'

    # print both url formats, so the user can use the correct one,
    # but also has every right to be incorrect
    < "$json" jq -r '.[0].result.data.url' >&2
    < "$json" jq -r '"https://cohost.org/rc/attachment-redirect/" + .[0].result.data.attachmentId'
done