Re: [PATCH] package-x.el: package-upload-buffer-internal

[Jambunathan K]

Chong Yidong <address@hidden> writes:

> Jambunathan K <address@hidden> writes:
>
>> 1. M-x package-upload-file currently downloads 'archive-contents' from a
>>    remote location and writes back the updated file to
>>    package-archive-upload-base. This seems inconsistent to me. The
>>    attached fix addresses this inconsistency.
>

>
> By the way, in the future, please post context diffs ("diff -c", or use
> the diff utilities built into Emacs).  I find it difficult to read the
> diff you sent. 

Re-attaching the 'diff -c' output. Hope it is OK now.

> Thanks for the patch, but could you explain why you think the current
> behavior is inconsistent?  The reason it downloads archive-contents is
> that the local copy might be out of date.  

> Before changing archive-contents, it should be necessary to make sure
> you're working on the most recent copy.

What is a remote-site for the user is a "local-machine" for the package
maintainer/uploader.

The assumption I make is that 'package-archive-upload-base' points to
the 'pub' dir of the webserver. It is the 'archive-contents' in this dir
that the webserver is essentially going to serve. So 'archive-contents'
retrieved through the URL would be the same as that read from
'package-archive-base'.

The implicit assumption in your argument/package-x seems to be that
there are multiple agents that write to the web-server and the one
running package-upload-file is just one such agent [1].

The above distributed scenario is less likely to arise for
one-package-only repos like Orgmode. I think it is essential that be
package-x also account for simple local ELPA repos.

Specifically, the use-case scenario that I have in mind is:

1. make all
2. make pkg
3. make pkg-upload
   pkg-upload: pkg
        $(BATCH) $(BATCH_EXTRA)                                         \
         --eval "(require 'package-x)"                                  \
         --eval '(setq package-archive-upload-base $(PKG_UPLOAD_DIR))'  \
         --eval '(setq package-update-news-on-upload nil)'              \
         --eval '(package-upload-file "org-$(PKG_TAG).tar")'

all in the same local machine that acts both as a build-machine and
webserver.

I would like to bring your attention to little things that my patch
introduces:

1. Setting package-update-news-on-upload to nil would be light on the
   maintainer (i.e., two less files to contend with)

2. Permit non-existent 'archive-contents'. Common-case for first few
   months or for the new repos.

3. Having 'package-archive-upload-base' as nil is like standing on a
   shifting sand i.e., it is relative to whatever happens to be the
   'default-directory' right now.

   As I was working on this patch, I accidentally shifted to a new
   buffer (with a different 'default-directory') between writing of
   'archive-contents' and writing of the tar ball. I was little bit
   taken surprised to notice the two fragments going their own ways.

   Local variable 'upload-dir' guards against such unintended goof-ups.

Footnotes:
=========
[1] I am unable to comprehend the details of how master and agents
    interact with each other. I am also unable to explain how writing to
    'package-archive-upload-base' would get reflected in the
    webserver/master.

[2] Included as recipe for others.

Jambunathan K.

Attachments:

*** package-x.el        2010-11-01 22:33:40.843750000 +0530
--- package-x-modified.el       2010-11-01 22:33:43.281250000 +0530
***************
*** 40,45 ****
--- 40,48 ----
  (defvar package-archive-upload-base nil
    "Base location for uploading to package archive.")
  
+ (defvar package-update-news-on-upload t
+   "Should package upload also update NEWS and RSS feeds?.")
+ 
  (defun package--encode (string)
    "Encode a string by replacing some characters with XML entities."
    ;; We need a special case for translating "&" to "&amp;".
***************
*** 86,91 ****
--- 89,127 ----
        (unless old-buffer
          (kill-buffer (current-buffer)))))))
  
+ (defun package--archive-contents-from-url (&optional archive-url) 
+   "Parse archive-contents file at ARCHIVE-URL.
+ 
+ If ARCHIVE-URL is unspecified the \"gnu\" archive is used."
+   (unless archive-url
+     (or (setq archive-url (cdr (assoc "gnu" package-archives)))
+       (error "No destination URL")))
+ 
+   (let* ((buffer (url-retrieve-synchronously
+                 (concat archive-url "archive-contents"))))
+     (set-buffer buffer)
+     (package-handle-response)
+     (re-search-forward "^$" nil 'move)
+     (forward-char)
+     (delete-region (point-min) (point))
+     (prog1 (package-read-from-string
+           (buffer-substring-no-properties (point-min) (point-max)))
+           (kill-buffer buffer))))
+ 
+ (defun package--archive-contents-from-file (file)
+   "Parse the given archive-contents file."
+   (if (not (file-exists-p file))
+       ;; no existing archive-contents, possibly a new ELPA repo.
+       (list package-archive-version)
+     (let ((dont-kill (find-buffer-visiting file)))
+       (with-current-buffer (let ((find-file-visit-truename t))
+                            (find-file-noselect file))
+       (prog1
+           (package-read-from-string
+            (buffer-substring-no-properties (point-min) (point-max)))
+         (unless dont-kill
+           (kill-buffer (current-buffer))))))))
+     
  (defun package-maint-add-news-item (title description archive-url)
    "Add a news item to the ELPA web pages.
  TITLE is the title of the news item.
***************
*** 107,121 ****
  
  (defun package-upload-buffer-internal (pkg-info extension &optional 
archive-url)
    "Upload a package whose contents are in the current buffer.
  PKG-INFO is the package info, see `package-buffer-info'.
  EXTENSION is the file extension, a string.  It can be either
  \"el\" or \"tar\".
  
! Optional arg ARCHIVE-URL is the URL of the destination archive.
! If nil, the \"gnu\" archive is used."
!   (unless archive-url
!     (or (setq archive-url (cdr (assoc "gnu" package-archives)))
!       (error "No destination URL")))
    (save-excursion
      (save-restriction
        (let* ((file-type (cond
--- 143,159 ----
  
  (defun package-upload-buffer-internal (pkg-info extension &optional 
archive-url)
    "Upload a package whose contents are in the current buffer.
+ By default, package files and archive-contents are uploaded to
+ the `default-directory'. Set `package-archive-upload-base' to
+ override the default behaviour.
  PKG-INFO is the package info, see `package-buffer-info'.
  EXTENSION is the file extension, a string.  It can be either
  \"el\" or \"tar\".
  
! Optional arg ARCHIVE-URL is the URL of the destination archive to
! be embedded in the RSS file. If nil, the \"gnu\" archive is
! used. This arg is effective only when
! `package-update-news-on-upload' is non-nil."
    (save-excursion
      (save-restriction
        (let* ((file-type (cond
***************
*** 132,151 ****
             (commentary (aref pkg-info 4))
             (split-version (version-to-list pkg-version))
             (pkg-buffer (current-buffer))
  
!            ;; Download latest archive-contents.
!            (buffer (url-retrieve-synchronously
!                     (concat archive-url "archive-contents"))))
! 
!       ;; Parse archive-contents.
!       (set-buffer buffer)
!       (package-handle-response)
!       (re-search-forward "^$" nil 'move)
!       (forward-char)
!       (delete-region (point-min) (point))
!       (let ((contents (package-read-from-string
!                        (buffer-substring-no-properties (point-min)
!                                                        (point-max))))
              (new-desc (vector split-version requires desc file-type)))
          (if (> (car contents) package-archive-version)
              (error "Unrecognized archive version %d" (car contents)))
--- 170,179 ----
             (commentary (aref pkg-info 4))
             (split-version (version-to-list pkg-version))
             (pkg-buffer (current-buffer))
+            (upload-dir (or package-archive-upload-base default-directory)))
  
!       (let ((contents (package--archive-contents-from-file
!                        (concat upload-dir "archive-contents")))
              (new-desc (vector split-version requires desc file-type)))
          (if (> (car contents) package-archive-version)
              (error "Unrecognized archive version %d" (car contents)))
***************
*** 166,197 ****
                (print-length nil))
            (write-region (concat (pp-to-string contents) "\n")
                          nil
!                         (concat package-archive-upload-base
!                                 "archive-contents")))
  
          ;; If there is a commentary section, write it.
          (when commentary
            (write-region commentary nil
!                         (concat package-archive-upload-base
                                  (symbol-name pkg-name) "-readme.txt")))
  
          (set-buffer pkg-buffer)
-         (kill-buffer buffer)
          (write-region (point-min) (point-max)
!                       (concat package-archive-upload-base
                                file-name "-" pkg-version
                                "." extension)
                        nil nil nil 'excl)
  
          ;; Write a news entry.
          (package--update-news (concat file-name "." extension)
!                               pkg-version desc archive-url)
  
          ;; special-case "package": write a second copy so that the
          ;; installer can easily find the latest version.
          (if (string= file-name "package")
              (write-region (point-min) (point-max)
!                           (concat package-archive-upload-base
                                    file-name "." extension)
                            nil nil nil 'ask)))))))
  
--- 194,228 ----
                (print-length nil))
            (write-region (concat (pp-to-string contents) "\n")
                          nil
!                         (concat upload-dir "archive-contents")))
  
          ;; If there is a commentary section, write it.
          (when commentary
            (write-region commentary nil
!                         (concat upload-dir
                                  (symbol-name pkg-name) "-readme.txt")))
  
          (set-buffer pkg-buffer)
          (write-region (point-min) (point-max)
!                       (concat upload-dir
                                file-name "-" pkg-version
                                "." extension)
                        nil nil nil 'excl)
  
          ;; Write a news entry.
+         (when package-update-news-on-upload
+           (unless archive-url
+             (or (setq archive-url (cdr (assoc "gnu" package-archives)))
+                 (error "No destination URL")))
+           
          (package--update-news (concat file-name "." extension)
!                                 pkg-version desc archive-url))
  
          ;; special-case "package": write a second copy so that the
          ;; installer can easily find the latest version.
          (if (string= file-name "package")
              (write-region (point-min) (point-max)
!                           (concat upload-dir
                                    file-name "." extension)
                            nil nil nil 'ask)))))))