#!/bin/sh
#―――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――
# Name: fedi2html.sh
# Desc:
# Reqs:
# Date:
#―――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――
# Return the ID of a post, based on its URL.
# url_id $url
url_id() {
local url="$1"
# Pleroma-style URLs: https://jam.xwx.moe/notice/Ac6PIZAP0ZzkMTYBBg
# Mastodon-style URLs: https://esperanto.masto.host/@minjo/111461250815264185
if echo "$url" | grep "/notice/" > /dev/null; then
echo "$url" \
| sed 's%.*/notice/%%'
else
echo "$url" \
| sed 's%.*/@[[:alnum:]]*/%%'
fi
}
# Return the server (including protocol) of a post, based on its URL.
# url_server $url
url_server() {
local url="$1"
local protocol="$(echo "$url" | grep --only-matching '[[:alnum:]]*://')"
printf "$protocol"
echo "$url" \
| sed 's%^'"$protocol"'%%' \
| sed 's%/.*%%'
}
# Make a request to the /api/v1/statuses/:id/$request API endpoint.
# statuses_api_request $post_url $request
statuses_api_request() {
local post_url="$1"
local api_request="$2"
if test -n "$api_request"; then
api_request="/$api_request"
fi
local id="$(url_id "$url")"
local server="$(url_server "$url")"
curl --location --header 'Accept: application/json,application/activity+json' \
"$server/api/v1/statuses/${id}${api_request}"
}
# Require the context-JSON of a post, by URL.
# fetch_post_context $url
fetch_post_context() {
local url="$1"
statuses_api_request "$url" "context"
}
# Given a post URL, request its JSON.
# fetch_post $url
fetch_post() {
local url="$1"
statuses_api_request "$url"
}
POST_TEMPLATE='
$ACCOUNT_NAME$ACCOUNT_ID
$POST_CONTENT
'
ATTACH_IMAGE_TEMPLATE='
$ATTACH_NAME
$(if test $(echo "$ATTACH_DESC" | wc -c) -gt 52; then
echo $ATTACH_DESC | head -c 53 | sed 's%[[:space:]]*$%%'
echo …
else
echo $ATTACH_DESC
fi)
'
EMOJI_TEMPLATE=''
# Accepts a string over stdin; it will replace all emoji shortcodes along stdin
# input with appropriate HTML, based on $EMOJI_TEMPLATE, and based on
# a post’s JSON.
# echo ":blobcat:" | replace_emojis $post_data
replace_emojis() {
local post_data="$1"
local emojis="$(echo "$post_data" | jq -r '.emojis[]|(.url + "\t" + .shortcode)')"
local temp="$(mktemp)"
local IFS="
"
cat > "$temp"
for line in $emojis; do
local EMOJI_URL="$(echo "$line" | awk -F'\t' '{print $1}')"
local EMOJI_SHORTCODE="$(echo "$line" | awk -F'\t' '{print $2}')"
local value="$(env_subst "$EMOJI_TEMPLATE")"
sed -i "s%:${EMOJI_SHORTCODE}:%${value}%g" "$temp"
done
cat "$temp"
rm "$temp"
}
# Given a post’s JSON data, return the appropriate HTML corresponding to its
# media attachments, if any. Will return an empty string if none.
# media_attachments $post_data
media_attachments() {
local post_data="$1"
local attachments="$(echo "$post_data" | jq -r '.media_attachments[]|(.type + "\t" + .url + "\t" + .description + "\t" + .preview_url)')"
local IFS="
"
for line in $attachments; do
local ATTACH_TYPE="$(echo "$line" | awk -F'\t' '{print $1}')"
local ATTACH_URL="$(echo "$line" | awk -F'\t' '{print $2}')"
local ATTACH_DESC="$(echo "$line" | awk -F'\t' '{print $3}')"
local ATTACH_PREVIEW="$(echo "$line" | awk -F'\t' '{print $4}')"
local ATTACH_NAME="$(basename "$ATTACH_URL")"
if test "$ATTACH_TYPE" = "image"; then
env_subst "$ATTACH_IMAGE_TEMPLATE"
else
env_subst "$ATTACH_TEMPLATE"
fi
done
}
# Sanitize a template-string.
# AKA, escape quotation-marks.
# prep_template $template
prep_template() {
local template="$1"
echo "$template" \
| sed 's%\"%\\\"%g'
}
# Rough replacement for gettext’s envsubst. Safe!
# This will evaluate a string’s shell variables (somewhat) safely
# Probably not good for general use — but for our purposes, it only subsitutes
# along the “first level.” So environment variables are replaced, but those
# variables’ contents (AKA, post contents) aren’t evaluated.
# env_subst $template
# env_subst "$SHELL" → "/bin/sh"
env_subst() {
local template="$1"
eval "echo \"$(prep_template "$template")\""
}
# Given a note’s JSON, render it as HTML.
# The most important part of the script!
# render_post $post_data
render_post() {
local post_data="$1"
local ACCOUNT_URL="$(echo "$post_data" | jq -r .account.url)"
local ACCOUNT_ID="$(echo "$post_data" | jq -r .account.fqn)"
local ACCOUNT_NAME="$(echo "$post_data" | jq -r .account.display_name | replace_emojis "$post_data")"
local ACCOUNT_AVATAR="$(echo "$post_data" | jq -r .account.avatar)"
local POST_URL="$(echo "$post_data" | jq -r .url)"
local POST_DATE="$(echo "$post_data" | jq -r .created_at)"
local POST_CONTENT="$(echo "$post_data" | jq -r .content | replace_emojis "$post_data")"
local POST_ATTACHMENTS="$(media_attachments "$post_data")"
env_subst "$POST_TEMPLATE"
}