sfeed_json: add JSON output format tool - sfeed - RSS and Atom parser
(HTM) git clone git://git.codemadness.org/sfeed
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(DIR) Files
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(DIR) README
(DIR) LICENSE
---
(DIR) commit ced0dd7f8a01dedad3ba16c4cf209aea673c3e82
(DIR) parent 3f1d323497e5aefce65a3758d1bc408130d9bbe0
(HTM) Author: Hiltjo Posthuma <hiltjo@codemadness.org>
Date: Mon, 10 Apr 2023 17:03:57 +0200
sfeed_json: add JSON output format tool
This outputs the TSV data to JSON.
It uses a subset of JSON Feed 1.1:
https://www.jsonfeed.org/version/1.1/
Diffstat:
M Makefile | 1 +
M README | 1 +
A sfeed_json.1 | 48 +++++++++++++++++++++++++++++++
A sfeed_json.c | 171 +++++++++++++++++++++++++++++++
4 files changed, 221 insertions(+), 0 deletions(-)
---
(DIR) diff --git a/Makefile b/Makefile
@@ -51,6 +51,7 @@ BIN = \
sfeed_frames\
sfeed_gopher\
sfeed_html\
+ sfeed_json\
sfeed_mbox\
sfeed_opml_import\
sfeed_plain\
(DIR) diff --git a/README b/README
@@ -186,6 +186,7 @@ sfeed_curses - Format feed data (TSV) to a curses interface.
sfeed_frames - Format feed data (TSV) to HTML file(s) with frames.
sfeed_gopher - Format feed data (TSV) to Gopher files.
sfeed_html - Format feed data (TSV) to HTML.
+sfeed_json - Format feed data (TSV) to JSON Feed.
sfeed_opml_export - Generate an OPML XML file from a sfeedrc config file.
sfeed_opml_import - Generate a sfeedrc config file from an OPML XML file.
sfeed_markread - Mark items as read/unread, for use with sfeed_curses.
(DIR) diff --git a/sfeed_json.1 b/sfeed_json.1
@@ -0,0 +1,48 @@
+.Dd March 8, 2023
+.Dt SFEED_JSON 1
+.Os
+.Sh NAME
+.Nm sfeed_json
+.Nd format feed data to JSON Feed
+.Sh SYNOPSIS
+.Nm
+.Op Ar
+.Sh DESCRIPTION
+.Nm
+formats feed data (TSV) from
+.Xr sfeed 1
+from stdin or for each
+.Ar file
+to stdout as JSON Feed data.
+If one or more
+.Ar file
+arguments are specified then the basename of the
+.Ar file
+is used as the feed name in the output.
+If no
+.Ar file
+arguments are specified and so the data is read from stdin then the feed name
+is empty.
+If
+.Nm
+is reading from one or more
+.Ar file
+arguments it will prefix the entry title with "[feed name] ".
+.Sh EXIT STATUS
+.Ex -std
+.Sh EXAMPLES
+.Bd -literal
+curl -s 'https://codemadness.org/atom.xml' | sfeed | sfeed_json
+.Ed
+.Sh SEE ALSO
+.Xr sfeed 1 ,
+.Xr sfeed_atom 1 ,
+.Xr sfeed 5
+.Sh STANDARDS
+.Rs
+.%T JSON Feed Version 1.1
+.%U https://www.jsonfeed.org/version/1.1/
+.%D Nov, 2022
+.Re
+.Sh AUTHORS
+.An Hiltjo Posthuma Aq Mt hiltjo@codemadness.org
(DIR) diff --git a/sfeed_json.c b/sfeed_json.c
@@ -0,0 +1,171 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "util.h"
+
+static char *line;
+static size_t linesize;
+static int firstitem = 1;
+
+/* Unescape / decode fields printed by string_print_encoded() */
+static void
+printcontent(const char *s)
+{
+ for (; *s; s++) {
+ switch (*s) {
+ case '\\':
+ s++;
+ switch (*s) {
+ case 'n': fputs("\\n", stdout); break;
+ case '\\': fputs("\\\\", stdout); break;
+ case 't': fputs("\\t", stdout); break;
+ }
+ break; /* ignore invalid escape sequence */
+ case '"': fputs("\\\"", stdout); break;
+ default:
+ putchar(*s);
+ break;
+ }
+ }
+}
+
+static void
+printfield(const char *s)
+{
+ for (; *s; s++) {
+ if (*s == '\\')
+ fputs("\\\\", stdout);
+ else if (*s == '"')
+ fputs("\\\"", stdout);
+ else
+ putchar(*s);
+ }
+}
+
+static void
+printfeed(FILE *fp, const char *feedname)
+{
+ char *fields[FieldLast], timebuf[32];
+ struct tm parsedtm, *tm;
+ time_t parsedtime;
+ ssize_t linelen;
+ int ch;
+ char *p, *s;
+
+ while ((linelen = getline(&line, &linesize, fp)) > 0 &&
+ !ferror(stdout)) {
+ if (line[linelen - 1] == '\n')
+ line[--linelen] = '\0';
+ parseline(line, fields);
+
+ if (!firstitem)
+ fputs(",\n", stdout);
+ firstitem = 0;
+
+ fputs("{\n\t\"id\": \"", stdout);
+ printfield(fields[FieldId]);
+ fputs("\"", stdout);
+
+ parsedtime = 0;
+ if (!strtotime(fields[FieldUnixTimestamp], &parsedtime) &&
+ (tm = gmtime_r(&parsedtime, &parsedtm)) &&
+ strftime(timebuf, sizeof(timebuf), "%Y-%m-%dT%H:%M:%SZ", tm)) {
+ fputs(",\n\t\"date_published\": \"", stdout);
+ fputs(timebuf, stdout);
+ fputs("\"", stdout);
+ }
+
+ fputs(",\n\t\"title\": \"", stdout);
+ if (feedname[0]) {
+ fputs("[", stdout);
+ printfield(feedname);
+ fputs("] ", stdout);
+ }
+ printfield(fields[FieldTitle]);
+ fputs("\"", stdout);
+
+ if (fields[FieldLink][0]) {
+ fputs(",\n\t\"url\": \"", stdout);
+ printfield(fields[FieldLink]);
+ fputs("\"", stdout);
+ }
+
+ if (fields[FieldAuthor][0]) {
+ fputs(",\n\t\"authors\": [{\"name\": \"", stdout);
+ printfield(fields[FieldAuthor]);
+ fputs("\"}]", stdout);
+ }
+
+ if (fields[FieldCategory][0]) {
+ fputs(",\n\t\"tags\": [", stdout);
+
+ for (p = s = fields[FieldCategory]; ; s++) {
+ if (*s == '|' || *s == '\0') {
+ if (p != fields[FieldCategory])
+ fputs(", ", stdout);
+ ch = *s;
+ *s = '\0'; /* temporary NUL terminate */
+ fputs("\"", stdout);
+ printfield(p);
+ fputs("\"", stdout);
+ *s = ch; /* restore */
+ p = s + 1;
+ }
+ if (*s == '\0')
+ break;
+ }
+ fputs("]", stdout);
+ }
+
+ if (fields[FieldEnclosure][0]) {
+ fputs(",\n\t\"attachments\": [{\"url:\": \"", stdout);
+ printfield(fields[FieldEnclosure]);
+ fputs("\"}]", stdout);
+ }
+
+ if (!strcmp(fields[FieldContentType], "html"))
+ fputs(",\n\t\"content_html\": \"", stdout);
+ else
+ fputs(",\n\t\"content_text\": \"", stdout);
+ printcontent(fields[FieldContent]);
+ fputs("\"\n}", stdout);
+ }
+}
+
+int
+main(int argc, char *argv[])
+{
+ FILE *fp;
+ char *name;
+ int i;
+
+ if (pledge(argc == 1 ? "stdio" : "stdio rpath", NULL) == -1)
+ err(1, "pledge");
+
+ fputs("{\n"
+ "\"version\": \"https://jsonfeed.org/version/1.1\",\n"
+ "\"title\": \"Newsfeed\",\n"
+ "\"items\": [\n", stdout);
+
+ if (argc == 1) {
+ printfeed(stdin, "");
+ checkfileerror(stdin, "<stdin>", 'r');
+ } else {
+ for (i = 1; i < argc; i++) {
+ if (!(fp = fopen(argv[i], "r")))
+ err(1, "fopen: %s", argv[i]);
+ name = ((name = strrchr(argv[i], '/'))) ? name + 1 : argv[i];
+ printfeed(fp, name);
+ checkfileerror(fp, argv[i], 'r');
+ checkfileerror(stdout, "<stdout>", 'w');
+ fclose(fp);
+ }
+ }
+ fputs("]\n}\n", stdout);
+
+ checkfileerror(stdout, "<stdout>", 'w');
+
+ return 0;
+}