User Tools

Site Tools


content:tech:rhizome_retriever

Differences

This shows you the differences between two versions of the page.

Link to this comparison view

content:tech:rhizome_retriever [25/09/2012 19:53]
Luke Marshall [Testing]
content:tech:rhizome_retriever [14/05/2013 23:18]
Line 1: Line 1:
-====== Rhizome for Citizen Journalism ====== 
-===== Mission(short) ===== 
  
-Create an application that allows to spread files over the mesh network by exchanging with servers that the handset can see (could be peers and web servers) 
-===== Some design elements ===== 
- 
-{{http://dl.dropbox.com/u/3505759/serval/images/design_elements.png}} 
- 
-A Rhizome logical file is constituted of three elements: 
-  * The data file (ex: serval.apk): the actual data 
-  * The meta file (.serval.apk.meta): contains <strong>local </strong>informations  
-    * When the file appeared on our repository? 
-    * Has the file been already read?<br />''''&gt; It's a personal file, never exchanged but **generated when a file gets into your repository** (ie, when imported or downloaded) 
-  * The manifest file (.serval.apk.manifest)  
-    * Contains static information on the file (author/version/creation date/file name/hash) 
-    * It's a companion file ; when a file is exchanged, always comes with its manifest 
-A file can be imported from the local FS : informations are asked to create the manifest, and the meta is automatically generated. 
- 
-A file can be downloaded from another repository (an HTTP server -- can be another batphone or a classic server). It comes with its manifests, and the meta is built when the file is actually downloaded. Here is the algorythm for choosing what to do with a proposed file. 
-  * If the file exists and the version number in the new manifest is not greater, does nothin 
-  * If the file no longer exist (because it has been deleted), do nothing except &hellip; 
-  * If the version of the new manifest is greater, download the manifest 
-  * Download the file 
-  * Compute the checksum of the new file, and if it fits with the manifest, import the file in the repository. 
-Every 15s, the app : 
-  - Look for the peers 
-  - Locate all the possible manifests 
-  - Download interestings file 
-In the background. 
- 
-There are three important locations on the SD card: 
-  ***serval-rhizome**: the repository 
-  ***serval-rhizome-export**: the export folder 
-  ***serval-rhizome-temp**: the temporary folder 
-===== Features ===== 
-==== Implemented ==== 
-  * List all the files in your local Rhizome repository 
-  * Open (some) 
-  * Allow to import from a file picker (asks for some info to build the associated manifest, and the meta is created automatically) 
-  * Allow to delete a file on your Rhizome repository 
-  * Allow to see manifest's informations 
-  * Allow to mark the file as read (information stored in the meta file) 
-  * Allow to export a received file "out" of the Rhizome system -- for instance, if you want to keep it from evoluting 
-  * Download a manifest and a file from the cloud (will be another Rhizom or a standard web server)  
-    * If the file exists and the version number in the new manifest is not greater, does nothing 
-    * If the version of the new manifest is greater (or the phone does not have this manifest yet), downlaod the manifest 
-    * Download the file 
-    * Take the checksum of the new file, and if it fits with the manifest, import the file in the repository. 
-  * Background looking for other peers -- WIP 
-  * Background and periodic lookup for unknown -- or newer -- manifests in the neighbors and known hosts 
-  * Lots of notifications -- on update, on error, on import, on the screen :) (toast) 
-  * Auto refresh when a file comes from the network 
-  * Creates the architecture at the launch time, remove the unnecessary files when closing 
-  * Possibility of defining a static repo -- which will be tried each time, such as Serval update repository 
-  * Maintain an exclusion list -- the file you've downloaded and deleted, so you dont want them to reappear 15 s after. 
-  * Allow to reinit the exclusion list (in the menu) 
-==== Not yet implemented ==== 
-  * Opening all files type &hellip; Looks complicated, need to trigger the MIME type from extension [[http://stackoverflow.com/questions/7377361/open-a-file-as-android-file-explorer-does|StackOverflow]] 
-  * Message signature&hellip; I'm fighting with the keystores and algorithm. If you have an android example, i'll be glad to have a look. 
-  * Peer lookup and actual manifest list fetching -- i need the phones 
-==== It's-not-a-bug-it's-a-feature list ==== 
-  * The updates stop **after** the app is closed. This can be changed very easily if another behavior is preferred. 
-===== Demonstration scenario ===== 
- 
-**MAKE SURE YOUR SD CARD IS NOT MOUNTED ON A COMPUTER OR THE PROGRAM WILL CRASH WHILE STARTING!** 
- 
-Android doesn't manage to access to a filesystem which is already mounted somewhere else. 
-  - Start the app 
-  - Wait for the files to appear from the network 
-  - Try to look their manifest 
-  - Look at the content of one of the meta file (especially date) 
-  - Delete one of the file 
-  - The file does NOT come back, because you've deleted it. 
-  - Reinit the exclusion list (in the menu) 
-  - When its comes back, check the meta date; should have evolved to the new date 
-  - Import a file (menu) 
-  - Give informations to build the manifest 
-  - Modify the .manifest to change the hash (into a wrong one) 
-  - Check the Manifest view : you should see a warning saying the hash is wrong 
-  - Increment the version number of one of the remote file and observe the update process (check in the manifest version number to ensure the update process went right. 
-  - Delete a file, and increment the number in the remote manifest file ; the file should come back because the number is greater and you deleted the last version, not this one. 
-  - Increment the version number of one of the remote manifest file and change the associated hash. The file wont update, because the hash is wrong. 
-  - Export one the file to rhizhome-serval-export 
-  - Quit the program, it will kill the update process and clear the cache directory. 
- 
-===== Interface ===== 
- 
-In order to demonstrate how bad I am with the UI, I made this small screenshots. Romana, I know you'll hate me. 
- 
-{{http://dl.dropbox.com/u/3505759/serval/images/base_w_menu.png}} 
- 
-The base application wihen the menu key is pressed. 
-{{http://dl.dropbox.com/u/3505759/serval/images/context_menu.png}} 
- 
-Contextual menu 
- 
-{{http://dl.dropbox.com/u/3505759/serval/images/deletion.png}} 
- 
-If I delete a file, here is the feedback (the file's no longer in the list) 
-{{http://dl.dropbox.com/u/3505759/serval/images/import.png}} 
- 
-Import a file from a picker. 
- 
-{{http://dl.dropbox.com/u/3505759/serval/images/manifest.png}} 
- 
-Add some data to the manifest 
-{{http://dl.dropbox.com/u/3505759/serval/images/manifest_view.png}} 
- 
-Later, you can check the manifest using the menu 
- 
-{{http://dl.dropbox.com/u/3505759/serval/images/update_from_network.png}} 
- 
-The file database.xml has been updated to the version 58 from the network (background update, no action from the user) 
-===== Code source ===== 
- 
-The code source is on GitHub : https://github.com/rbochet/Rhizome-Retriever 
- 
-You're more than welcome to fork / push if you find a bug you can fix in a second. 
-===== Testing ===== 
- 
-You can import easily the project in Eclipse, there are no external dependencies. 
-\\ 
-The only _strange//thing for the moment is that if you want to test using the network updates, you'll have to have a place on the web where you can put manifests and files. My files are here: 
- 
-\\ 
-\\ 
- 
-  * [[http://dl.dropbox.com/u/3505759/serval/.database.xml.manifest]] (and [[http://dl.dropbox.com/u/3505759/serval/database.xml]]) 
-\\ 
-  * [[http://dl.dropbox.com/u/3505759/serval/.disable-lagfix.truite.manifest]] (and [[http://dl.dropbox.com/u/3505759/serval/disable-lagfix.truite]]) 
- 
-\\ 
-\\ 
- 
-But there's more fun if you can change their version number, and play with the file hash to test the functions&hellip; So find a place on the web where you can put them and where you have writing permissions. 
-\\ 
-If you want to try with other files, just grab files you have already imported and their manifests from the serval-rhizome directory. 
-\\ 
-The path is to set up in the StuffDownloader class for testing purposes: 
-{{https://github.com/rbochet/Rhizome-Retriever/blob/master/src/org/servalproject/rr/StuffDownloader.java#L189}}. 
-\\ 
- 
- 
----- 
- 
-I may have been unclear in this documentation. If you dont understand something, send a mail romain@servalproject NOSPAM org or to the developer list. 
content/tech/rhizome_retriever.txt · Last modified: 14/05/2013 23:18 (external edit)