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* Import wiki pages
* Update README (including upgrade instructions)

README.md

@@ -90,3 +90,14 @@ and check for changes only every 60 seconds (configurable). So if you make a
 change to your documents, you won't see it immediately in the mounted
 filesystem.
 
+### Upgrading from 0.1pre2
+
+Since version 0.1pre3, the application uses Drive API v2, instead of Google
+Documents List API v3, so if you are upgrading from previous versions, you
+should clean every file in `~/.gdfuse/default`:
+
+    $ rm -rf ~/.gdfuse/default
+
+because the access token requested previously is not compatible with the new
+API.
+

doc/Authorization.md

@@ -0,0 +1,60 @@
+### Standard authorization mode
+
+Authorization is provided by a Google App Engine service (the source code of
+the service is [here](https://github.com/astrada/gd-ocaml-auth)). When you
+start the program without specifying a mountpoint,
+
+    $ google-drive-ocamlfuse
+
+the executable opens a web browser (using `xdg-open`, or, if `xdg-open` is not
+available, launching `firefox` or `google-chrome`), showing a page that will
+ask you to authorize access to your Google Drive. If you allow it, the Google
+authorization endpoint will connect to the GAE service, providing a
+verification code, that will be exchanged for an access token and a refresh
+token (for offline access). Meanwhile, `google-drive-ocamlfuse` polls the GAE
+service, asking for tokens, until it gets them, or there is an error, or a
+timeout triggers. If anything goes wrong, you can safely restart the
+application, and it will try to recover. If it cannot recover, you should
+clean the content of `~/.gdfuse/default` to start from scratch. Otherwise, if
+the application can retrieve the tokens, the program will exit and you may
+then mount the Google Drive filesystem. `google-drive-ocamlfuse` will also use
+the GAE service when it needs to refresh the access token (access tokens
+usually are valid for 60 minutes). The GAE service has two purposes: to make
+the authorization process simpler (removing all manual steps), and to avoid
+exposing the OAuth2 client secret of the application (otherwise anyone can
+impersonate it).
+
+### Alternative authorization mode
+
+If you don't trust the GAE service, there is an alternative way to authorize
+the application, that doesn't involve external services. If you have your own
+OAuth2 client ID and client secret, you may pass them on the command line (the
+first time you issue the application), e.g.:
+
+    $ google-drive-ocamlfuse -client_id 12345678.apps.googleusercontent.com -client_secret abcde12345
+
+This way, the application will use your credentials, and will not connect to
+the GAE service. A browser will be started pointing to an authorization page,
+and when you allow access to Google Drive, a verification code will be
+generated. You have to copy this verification code, and paste it in the
+console where the application is running.
+
+    Please enter the verification code: 1/12309afhaskfhlskhfklsfslkhfskhfskskdfh
+
+If everything goes fine, the application will notify you that it has retrieved
+the tokens from Google.
+
+    Access token retrieved correctly.
+
+You can create OAuth2 credentials from the Google APIs Console.
+[Here](https://developers.google.com/console/help/#creatingdeletingprojects)
+you can find how to create a new application and how to set up OAuth 2.0
+credentials. When creating a new client ID, you must select "Installed
+applications" as Application type and "Other" as Installed application type
+(Redirect URI should be `urn:ietf:wg:oauth:2.0:oob`).
+
+### Revoking access
+
+Anyway, you can always revoke access to Google Drive from
+[here](https://accounts.google.com/b/0/IssuedAuthSubTokens).
+

doc/Configuration.md

@@ -0,0 +1,56 @@
+The configuration file is saved in `~/.gdfuse/default/config` (or `~/.gdfuse/label/config` if a label was specified on the command line). The parser is very simple and only accepts lines in the form `key=value`, without spaces, comments, or anything else.
+
+### Content
+
+Specifies if debug mode is turned on: if `true`, logs verbose output to `~/.gdfuse/default/gdfuse.log`, and logs every curl request to `~/.gdfuse/default/curl.log`:
+
+    debug=true
+
+Specifies the interval in seconds between queries to detect server-side changes:
+
+    metadata_cache_time=60
+
+Specifies if the filesystem is to be mounted read-only (at this moment, write support is not yet implemented):
+
+    read_only=true
+
+Specifies the umask (i.e. the bitmask of  the  permissions  that  are  not present) mount option:
+
+    umask=0o002
+
+Specifies the Sqlite3 busy handler timeout in milliseconds:
+
+    sqlite3_busy_timeout=500
+
+Specifies whether to download Google Docs (these files are read-only, even if `read_only=false`):
+
+    download_docs=true
+
+Text document [export format](https://developers.google.com/google-apps/documents-list/#valid_download_formats_for_text_documents):
+
+    document_format=odt
+
+Drawings [export format](https://developers.google.com/google-apps/documents-list/#valid_download_formats_for_drawings):
+
+    drawing_format=png
+
+Forms [export format](https://developers.google.com/google-apps/documents-list/#valid_formats_for_spreadsheets):
+
+    form_format=ods
+
+Presentations [export format](https://developers.google.com/google-apps/documents-list/#valid_formats_for_presentations):
+
+    presentation_format=pdf
+
+Spreadsheets [export format](https://developers.google.com/google-apps/documents-list/#valid_formats_for_spreadsheets):
+
+    spreadsheet_format=ods
+
+OAuth2 client ID (optional)
+
+    client_id=
+
+OAuth2 client secret (optional)
+
+    client_secret=
+

doc/Home.md

@@ -0,0 +1,4 @@
+Welcome to the google-drive-ocamlfuse wiki!
+
+* [[Authorization]]
+* [[Configuration]]