Reuse more code between gcloud and json formatting

Author: Thomasdezeeuw

src/format/gcloud.rs

@@ -1,13 +1,10 @@
 //! Google Cloud Platform structured logging using JSON, following
 //! <https://cloud.google.com/logging/docs/structured-logging>.
 
-use std::fmt::{self, Write};
 use std::io::IoSlice;
 
 use log::{kv, Record};
 
-#[cfg(feature = "timestamp")]
-use crate::format::format_timestamp;
 use crate::format::json;
 use crate::format::{Buffer, Format, BUFS_SIZE};
 use crate::PANIC_TARGET;
@@ -28,18 +25,18 @@ impl Format for Gcloud {
         // Write all parts of the buffer that need formatting.
         buf.buf[0] = b'{';
         #[cfg(feature = "timestamp")]
-        write_timestamp(buf);
-        write_msg(buf, record.args());
-        write_key_values(buf, record.key_values(), kvs);
+        json::write_timestamp(buf);
+        json::write_msg(buf, record.args());
+        json::write_key_values(buf, record.key_values(), kvs);
         if add_loc {
-            write_line(buf, record.line().unwrap_or(0));
+            json::write_line(buf, record.line().unwrap_or(0));
         }
 
         // Now that we've written the message to our buffer we have to construct it.
         // The first part of the message is the timestamp and log level (severity),
         // e.g. `{"timestamp":"2020-12-31T12:32:23.906132Z","severity":"INFO`.
         // Or without a timestamp, i.e. `{"severity":"INFO`.
-        bufs[0] = IoSlice::new(timestamp(buf));
+        bufs[0] = IoSlice::new(json::timestamp(buf));
         bufs[1] = IoSlice::new(b"\"severity\":\"");
         if record.level() == log::Level::Error && record.target() == PANIC_TARGET {
             // If we're panicking we increase the severity to critical.
@@ -49,23 +46,23 @@ impl Format for Gcloud {
         }
         // The message (and the end of the log level), e.g. `","message":"some message`.
         bufs[3] = IoSlice::new(b"\",\"message\":\"");
-        bufs[4] = IoSlice::new(msg(buf));
+        bufs[4] = IoSlice::new(json::msg(buf));
         // The target, e.g. `","target":"request`.
         bufs[5] = IoSlice::new(b"\",\"target\":\"");
         bufs[6] = IoSlice::new(record.target().as_bytes());
         // The module, e.g. `","module":"stored::http`.
         bufs[7] = IoSlice::new(b"\",\"module\":\"");
         bufs[8] = IoSlice::new(record.module_path().unwrap_or("").as_bytes());
         // Any key value pairs supplied by the user.
-        bufs[9] = IoSlice::new(key_values(buf));
+        bufs[9] = IoSlice::new(json::key_values(buf));
         // Optional file, e.g.
         // `","sourceLocation":{"file":"some_file.rs","line":"123"}}`, and a line
         // end.
         let n = if add_loc {
             bufs[10] = IoSlice::new(b",\"sourceLocation\":{\"file\":\"");
             bufs[11] = IoSlice::new(record.file().unwrap_or("??").as_bytes());
             bufs[12] = IoSlice::new(b"\",\"line\":\"");
-            bufs[13] = IoSlice::new(line(buf));
+            bufs[13] = IoSlice::new(json::line(buf));
             bufs[14] = IoSlice::new(b"\"}}\n");
             15
         } else {
@@ -76,90 +73,9 @@ impl Format for Gcloud {
     }
 }
 
-/// Index of the end of `{"timestamp":"0000-00-00T00:00:00.000000Z",`.
-#[cfg(feature = "timestamp")]
-const TS_END_INDEX: usize = 43;
-#[cfg(not(feature = "timestamp"))]
-const TS_END_INDEX: usize = 1;
-
-#[inline]
-#[cfg(feature = "timestamp")]
-fn write_timestamp(buf: &mut Buffer) {
-    let _ = buf.buf[TS_END_INDEX];
-    buf.buf[1] = b'"';
-    buf.buf[2] = b't';
-    buf.buf[3] = b'i';
-    buf.buf[4] = b'm';
-    buf.buf[5] = b'e';
-    buf.buf[6] = b's';
-    buf.buf[7] = b't';
-    buf.buf[8] = b'a';
-    buf.buf[9] = b'm';
-    buf.buf[10] = b'p';
-    buf.buf[11] = b'"';
-    buf.buf[12] = b':';
-    buf.buf[13] = b'"';
-    format_timestamp(&mut buf.buf[14..]);
-    buf.buf[TS_END_INDEX - 2] = b'"';
-    buf.buf[TS_END_INDEX - 1] = b',';
-}
-
-#[inline]
-fn timestamp(buf: &Buffer) -> &[u8] {
-    &buf.buf[..TS_END_INDEX]
-}
-
 #[inline]
 const fn severity(level: log::Level) -> &'static [u8] {
     // NOTE: gcloud doesn't have trace messages so we use debug twice.
     const SEVERITIES: [&[u8]; 6] = [b"OFF", b"ERROR", b"WARNING", b"INFO", b"DEBUG", b"DEBUG"];
     SEVERITIES[level as usize]
 }
-
-#[inline]
-fn write_msg(buf: &mut Buffer, args: &fmt::Arguments) {
-    buf.buf.truncate(TS_END_INDEX);
-    if let Some(msg) = args.as_str() {
-        json::Buf(&mut buf.buf)
-            .write_str(msg)
-            .unwrap_or_else(|_| unreachable!());
-    } else {
-        json::Buf(&mut buf.buf)
-            .write_fmt(*args)
-            .unwrap_or_else(|_| unreachable!());
-    }
-    buf.indices[0] = buf.buf.len();
-}
-
-#[inline]
-fn msg(buf: &Buffer) -> &[u8] {
-    &buf.buf[TS_END_INDEX..buf.indices[0]]
-}
-
-#[inline]
-fn write_key_values<Kvs: kv::Source>(buf: &mut Buffer, kvs1: &dyn kv::Source, kvs2: Kvs) {
-    buf.buf.extend_from_slice(b"\"");
-    // TODO: see if we can add to the slice of `IoSlice` using the keys
-    // and string values.
-    let mut visitor = json::KeyValueVisitor(&mut buf.buf);
-    kvs1.visit(&mut visitor).unwrap_or_else(|_| unreachable!());
-    kvs2.visit(&mut visitor).unwrap_or_else(|_| unreachable!());
-    buf.indices[1] = buf.buf.len();
-}
-
-#[inline]
-fn key_values(buf: &Buffer) -> &[u8] {
-    &buf.buf[buf.indices[0]..buf.indices[1]]
-}
-
-#[inline]
-fn write_line(buf: &mut Buffer, line: u32) {
-    let mut itoa = itoa::Buffer::new();
-    buf.buf.extend_from_slice(itoa.format(line).as_bytes());
-    buf.indices[2] = buf.buf.len();
-}
-
-#[inline]
-fn line(buf: &Buffer) -> &[u8] {
-    &buf.buf[buf.indices[1]..buf.indices[2]]
-}

src/format/json.rs

@@ -75,7 +75,7 @@ const TS_END_INDEX: usize = 1;
 
 #[inline]
 #[cfg(feature = "timestamp")]
-fn write_timestamp(buf: &mut Buffer) {
+pub(crate) fn write_timestamp(buf: &mut Buffer) {
     let _ = buf.buf[TS_END_INDEX];
     buf.buf[1] = b'"';
     buf.buf[2] = b't';
@@ -96,12 +96,12 @@ fn write_timestamp(buf: &mut Buffer) {
 }
 
 #[inline]
-fn timestamp(buf: &Buffer) -> &[u8] {
+pub(crate) fn timestamp(buf: &Buffer) -> &[u8] {
     &buf.buf[..TS_END_INDEX]
 }
 
 #[inline]
-fn write_msg(buf: &mut Buffer, args: &fmt::Arguments) {
+pub(crate) fn write_msg(buf: &mut Buffer, args: &fmt::Arguments) {
     buf.buf.truncate(TS_END_INDEX);
     if let Some(msg) = args.as_str() {
         Buf(&mut buf.buf)
@@ -116,12 +116,16 @@ fn write_msg(buf: &mut Buffer, args: &fmt::Arguments) {
 }
 
 #[inline]
-fn msg(buf: &Buffer) -> &[u8] {
+pub(crate) fn msg(buf: &Buffer) -> &[u8] {
     &buf.buf[TS_END_INDEX..buf.indices[0]]
 }
 
 #[inline]
-fn write_key_values<Kvs: kv::Source>(buf: &mut Buffer, kvs1: &dyn kv::Source, kvs2: Kvs) {
+pub(crate) fn write_key_values<Kvs: kv::Source>(
+    buf: &mut Buffer,
+    kvs1: &dyn kv::Source,
+    kvs2: Kvs,
+) {
     buf.buf.extend_from_slice(b"\"");
     // TODO: see if we can add to the slice of `IoSlice` using the keys
     // and string values.
@@ -132,19 +136,19 @@ fn write_key_values<Kvs: kv::Source>(buf: &mut Buffer, kvs1: &dyn kv::Source, kv
 }
 
 #[inline]
-fn key_values(buf: &Buffer) -> &[u8] {
+pub(crate) fn key_values(buf: &Buffer) -> &[u8] {
     &buf.buf[buf.indices[0]..buf.indices[1]]
 }
 
 #[inline]
-fn write_line(buf: &mut Buffer, line: u32) {
+pub(crate) fn write_line(buf: &mut Buffer, line: u32) {
     let mut itoa = itoa::Buffer::new();
     buf.buf.extend_from_slice(itoa.format(line).as_bytes());
     buf.indices[2] = buf.buf.len();
 }
 
 #[inline]
-fn line(buf: &Buffer) -> &[u8] {
+pub(crate) fn line(buf: &Buffer) -> &[u8] {
     &buf.buf[buf.indices[1]..buf.indices[2]]
 }