feat: auto-detect piped stdin for upload and extend processUtils I/O

When no paths are provided and stdin is a pipe (not a terminal), upload
now reads from piped stdin instead of printing the pre-signed URL. This
enables `echo data | rli obj upload --name foo --content-type text`
without explicitly passing `-`. Zero-byte pipes are handled correctly.

Extend processUtils with Buffer support on stdout/stderr.write and
AsyncIterable on stdin, so upload and download go through the mockable
abstraction instead of process globals directly.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: jason-rl

README.md

@@ -147,8 +147,8 @@ rli blueprint from-dockerfile            # Create a blueprint from a Dockerfile
 ```bash
 rli object list                          # List objects
 rli object get <id>                      # Get object details
-rli object download <id> [path]          # Download object to local file (path d...
-rli object upload [paths...]             # Upload file(s) or directory as an obj...
+rli object download <id> [path]          # Download an object. Omit path to save...
+rli object upload [paths...]             # Upload an object. Reads from piped st...
 rli object delete <id>                   # Delete an object (irreversible)
 ```
 

src/commands/object/download.ts

@@ -72,8 +72,7 @@ export async function downloadObject(options: DownloadObjectOptions) {
           "Warning: writing binary data to terminal; pipe to a file or command instead\n",
         );
       }
-      // Raw process.stdout for binary data (processUtils.stdout.write only accepts string)
-      process.stdout.write(buffer);
+      processUtils.stdout.write(buffer);
     } else {
       await writeFile(resolvedPath, buffer);
     }

src/commands/object/upload.ts

@@ -8,6 +8,7 @@ import { createTar, createTarGzip } from "nanotar";
 import type { TarFileInput } from "nanotar";
 import { getClient } from "../../utils/client.js";
 import { output, outputError } from "../../utils/output.js";
+import { processUtils } from "../../utils/processUtils.js";
 
 interface UploadObjectOptions {
   paths: string[];
@@ -163,7 +164,7 @@ export async function createTarBuffer(
 
 async function readStdinBuffer(): Promise<Buffer> {
   const chunks: Buffer[] = [];
-  for await (const chunk of process.stdin) {
+  for await (const chunk of processUtils.stdin) {
     chunks.push(Buffer.isBuffer(chunk) ? chunk : Buffer.from(chunk));
   }
   return Buffer.concat(chunks);
@@ -175,34 +176,40 @@ export async function uploadObject(options: UploadObjectOptions) {
     const { paths, name, contentType, output: outputFormat } = options;
 
     if (paths.length === 0) {
-      if (!name) {
-        outputError("--name is required when no paths are provided");
-      }
-      const resolvedContentType: ContentType =
-        (contentType as ContentType) || "unspecified";
+      if (!processUtils.stdin.isTTY) {
+        // Piped stdin detected — normalize to explicit stdin path below
+        paths.push("-");
+      } else {
+        // Interactive terminal: print pre-signed upload URL
+        if (!name) {
+          outputError("--name is required when no paths are provided");
+        }
+        const resolvedContentType: ContentType =
+          (contentType as ContentType) || "unspecified";
 
-      const createResponse = await client.objects.create({
-        name,
-        content_type: resolvedContentType,
-      });
+        const createResponse = await client.objects.create({
+          name,
+          content_type: resolvedContentType,
+        });
 
-      if (!createResponse.upload_url) {
-        outputError("API did not return an upload URL");
-      }
-
-      const result = {
-        id: createResponse.id,
-        name,
-        contentType: resolvedContentType,
-        uploadUrl: createResponse.upload_url,
-      };
+        if (!createResponse.upload_url) {
+          outputError("API did not return an upload URL");
+        }
 
-      if (!outputFormat || outputFormat === "text") {
-        console.log(createResponse.upload_url);
-      } else {
-        output(result, { format: outputFormat, defaultFormat: "json" });
+        const result = {
+          id: createResponse.id,
+          name,
+          contentType: resolvedContentType,
+          uploadUrl: createResponse.upload_url,
+        };
+
+        if (!outputFormat || outputFormat === "text") {
+          console.log(createResponse.upload_url);
+        } else {
+          output(result, { format: outputFormat, defaultFormat: "json" });
+        }
+        return;
       }
-      return;
     }
 
     const hasStdin = paths.includes("-");

src/utils/commands.ts

@@ -632,7 +632,7 @@ export function createProgram(): Command {
   object
     .command("download <id> [path]")
     .description(
-      "Download object to local file (path defaults to ./<name> with inferred extension; use - for stdout)",
+      "Download an object. Omit path to save as ./<name> with inferred extension. Use - to write to stdout.",
     )
     .option("--extract", "Extract downloaded archive after download")
     .option(
@@ -652,7 +652,7 @@ export function createProgram(): Command {
   object
     .command("upload [paths...]")
     .description(
-      "Upload file(s) or directory as an object. With no paths, creates the object and prints the upload URL. Use - to read from stdin.",
+      "Upload an object. Reads from piped stdin when no paths are given; prints a pre-signed upload URL if stdin is a terminal. Use - to explicitly read stdin. Multiple paths with --content-type tar|tgz creates an archive.",
     )
     .option("--name <name>", "Object name (required)")
     .option(

src/utils/processUtils.ts

@@ -29,15 +29,15 @@ export interface ProcessUtils {
    * Standard output operations
    */
   stdout: {
-    write: (data: string) => boolean;
+    write: (data: string | Buffer) => boolean;
     isTTY: boolean;
   };
 
   /**
    * Standard error operations
    */
   stderr: {
-    write: (data: string) => boolean;
+    write: (data: string | Buffer) => boolean;
     isTTY: boolean;
   };
 
@@ -52,6 +52,7 @@ export interface ProcessUtils {
       event: string,
       listener: (...args: unknown[]) => void,
     ) => void;
+    [Symbol.asyncIterator]: () => AsyncIterator<Buffer>;
   };
 
   /**
@@ -91,14 +92,14 @@ export const processUtils: ProcessUtils = {
   exit: originalExit,
 
   stdout: {
-    write: (data: string) => originalStdoutWrite(data),
+    write: (data: string | Buffer) => originalStdoutWrite(data),
     get isTTY() {
       return process.stdout.isTTY ?? false;
     },
   },
 
   stderr: {
-    write: (data: string) => originalStderrWrite(data),
+    write: (data: string | Buffer) => originalStderrWrite(data),
     get isTTY() {
       return process.stderr.isTTY ?? false;
     },
@@ -111,6 +112,8 @@ export const processUtils: ProcessUtils = {
     setRawMode: process.stdin.setRawMode?.bind(process.stdin),
     on: process.stdin.on.bind(process.stdin),
     removeListener: process.stdin.removeListener.bind(process.stdin),
+    [Symbol.asyncIterator]: () =>
+      process.stdin[Symbol.asyncIterator]() as AsyncIterator<Buffer>,
   },
 
   cwd: originalCwd,
@@ -130,8 +133,10 @@ export const processUtils: ProcessUtils = {
  */
 export function resetProcessUtils(): void {
   processUtils.exit = originalExit;
-  processUtils.stdout.write = (data: string) => originalStdoutWrite(data);
-  processUtils.stderr.write = (data: string) => originalStderrWrite(data);
+  processUtils.stdout.write = (data: string | Buffer) =>
+    originalStdoutWrite(data);
+  processUtils.stderr.write = (data: string | Buffer) =>
+    originalStderrWrite(data);
   processUtils.cwd = originalCwd;
   processUtils.on = originalOn;
   processUtils.off = originalOff;
@@ -161,6 +166,7 @@ export function createMockProcessUtils(): ProcessUtils {
       setRawMode: () => {},
       on: () => {},
       removeListener: () => {},
+      async *[Symbol.asyncIterator]() {},
     },
     cwd: () => "/mock/cwd",
     on: () => {},