1 Installing the Evergreen server
2 ===============================
6 Preamble: referenced user accounts
7 ----------------------------------
9 In subsequent sections, we will refer to a number of different accounts, as
12 * Linux user accounts:
13 ** The *user* Linux account is the account that you use to log onto the
14 Linux system as a regular user.
15 ** The *root* Linux account is an account that has system administrator
16 privileges. On Debian you can switch to this account from
17 your *user* account by issuing the `su -` command and entering the
18 password for the *root* account when prompted. On Ubuntu you can switch
19 to this account from your *user* account using the `sudo su -` command
20 and entering the password for your *user* account when prompted.
21 ** The *opensrf* Linux account is an account that you create when installing
22 OpenSRF. You can switch to this account from the *root* account by
23 issuing the `su - opensrf` command.
24 ** The *postgres* Linux account is created automatically when you install
25 the PostgreSQL database server. You can switch to this account from the
26 *root* account by issuing the `su - postgres` command.
27 * PostgreSQL user accounts:
28 ** The *evergreen* PostgreSQL account is a superuser account that you will
29 create to connect to the PostgreSQL database server.
30 * Evergreen administrator account:
31 ** The *egadmin* Evergreen account is an administrator account for
32 Evergreen that you will use to test connectivity and configure your
35 Preamble: developer instructions
36 --------------------------------
39 Skip this section if you are using an official release tarball downloaded
40 from http://evergreen-ils.org/egdownloads
42 Developers working directly with the source code from the Git repository,
43 rather than an official release tarball, must perform one step before they
44 can proceed with the `./configure` step.
46 As the *user* Linux account, issue the following command in the Evergreen
47 source directory to generate the configure script and Makefiles:
50 ------------------------------------------------------------------------------
52 ------------------------------------------------------------------------------
54 Installing prerequisites
55 ------------------------
57 * **PostgreSQL**: The minimum supported version is 9.4.
58 * **Linux**: Evergreen has been tested on Debian Stretch (9),
59 Debian Jessie (8), Debian Wheezy (7), Ubuntu Xenial Xerus (16.04),
60 and Ubuntu Trusty Tahr (14.04).
61 If you are running an older version of these distributions, you may want
62 to upgrade before upgrading Evergreen. For instructions on upgrading these
63 distributions, visit the Debian or Ubuntu websites.
64 * **OpenSRF**: The minimum supported version of OpenSRF is 3.0.0.
67 Evergreen has a number of prerequisite packages that must be installed
68 before you can successfully configure, compile, and install Evergreen.
70 1. Begin by installing the most recent version of OpenSRF (3.0.0 or later).
71 You can download OpenSRF releases from http://evergreen-ils.org/opensrf-downloads/
72 2. On some distributions, it is necessary to install PostgreSQL 9.4+ from external
75 * Debian (Wheezy) and Ubuntu (Trusty) comes with older versions of
76 PostgreSQL, so steps are taken to automatically utilize the
77 PostgreSQL community's apt sources.
78 (For complete details, see: https://wiki.postgresql.org/wiki/Apt)
79 * Debian (Jessie/Stretch) and Ubuntu (Xenial) comes with PostgreSQL 9.4+,
80 so no additional steps are required.
82 3. Issue the following commands as the *root* Linux account to install
83 prerequisites using the `Makefile.install` prerequisite installer,
84 substituting `debian-stretch`, `debian-jessie`, `debian-wheezy`,
85 `ubuntu-xenial`, or `ubuntu-trusty` for <osname> below:
88 ------------------------------------------------------------------------------
89 make -f Open-ILS/src/extras/Makefile.install <osname>
90 ------------------------------------------------------------------------------
92 4. Add the libdbi-libdbd libraries to the system dynamic library path by
93 issuing the following commands as the *root* Linux account:
96 You should skip this step if installing on Ubuntu Trusty/Xenial or Debian Jessie/Stretch. The Ubuntu
97 and Debian Jessie/Stretch targets use libdbd-pgsql from packages.
101 ------------------------------------------------------------------------------
102 echo "/usr/local/lib/dbd" > /etc/ld.so.conf.d/eg.conf
104 ------------------------------------------------------------------------------
106 5. OPTIONAL: Developer additions
108 To perform certain developer tasks from a Git source code checkout,
109 additional packages may be required. As the *root* Linux account:
111 * To install packages needed for retrieving and managing web dependencies,
112 use the <osname>-developer Makefile.install target. Currently,
113 this is only needed for building and installing the (preview) browser
117 ------------------------------------------------------------------------------
118 make -f Open-ILS/src/extras/Makefile.install <osname>-developer
119 ------------------------------------------------------------------------------
121 * To install packages required for building Evergreen translations, use
122 the <osname>-translator Makefile.install target.
125 ------------------------------------------------------------------------------
126 make -f Open-ILS/src/extras/Makefile.install <osname>-translator
127 ------------------------------------------------------------------------------
129 * To install packages required for building Evergreen release bundles, use
130 the <osname>-packager Makefile.install target.
133 ------------------------------------------------------------------------------
134 make -f Open-ILS/src/extras/Makefile.install <osname>-packager
135 ------------------------------------------------------------------------------
137 Extra steps for web staff client
138 --------------------------------
141 Skip this entire section if you are using an official release tarball downloaded
142 from http://evergreen-ils.org/downloads
144 Install dependencies for web staff client
145 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
148 You may skip this section if you have installed the previously described
149 'Optional: Developer Additions'. You will still need to do the following
150 steps in <<install_files_for_web_staff_client,Install files for web staff client>>.
152 1. Install the long-term stability (LTS) release of
153 https://nodejs.org[Node.js]. Add the Node.js `/bin` directory to your
154 environment variable `PATH`.
156 [[install_files_for_web_staff_client]]
157 Install files for web staff client
158 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
160 1. Building, Testing, Minification: The remaining steps all take place within
161 the staff JS web root:
164 ------------------------------------------------------------------------------
165 cd $EVERGREEN_ROOT/Open-ILS/web/js/ui/default/staff/
166 ------------------------------------------------------------------------------
168 2. Install Project-local Dependencies. npm inspects the 'package.json' file
169 for dependencies and fetches them from the Node package network.
172 ------------------------------------------------------------------------------
173 npm install # fetch JS dependencies
174 ------------------------------------------------------------------------------
176 3. Run the build script.
179 ------------------------------------------------------------------------------
180 # build, run tests, concat+minify
183 ------------------------------------------------------------------------------
185 Configuration and compilation instructions
186 ------------------------------------------
188 For the time being, we are still installing everything in the `/openils/`
189 directory. From the Evergreen source directory, issue the following commands as
190 the *user* Linux account to configure and build Evergreen:
193 ------------------------------------------------------------------------------
194 PATH=/openils/bin:$PATH ./configure --prefix=/openils --sysconfdir=/openils/conf
196 ------------------------------------------------------------------------------
198 These instructions assume that you have also installed OpenSRF under `/openils/`.
199 If not, please adjust PATH as needed so that the Evergreen `configure` script
200 can find `osrf_config`.
202 Installation instructions
203 -------------------------
205 1. Once you have configured and compiled Evergreen, issue the following
206 command as the *root* Linux account to install Evergreen, build the server
207 portion of the staff client, and copy example configuration files to
209 Change the value of the `STAFF_CLIENT_STAMP_ID` variable to match the version
210 of the staff client that you will use to connect to the Evergreen server.
213 ------------------------------------------------------------------------------
214 make STAFF_CLIENT_STAMP_ID=rel_name install
215 ------------------------------------------------------------------------------
217 2. The server portion of the staff client expects `http://hostname/xul/server`
218 to resolve. Issue the following commands as the *root* Linux account to
219 create a symbolic link pointing to the `server` subdirectory of the server
220 portion of the staff client that we just built using the staff client ID
224 ------------------------------------------------------------------------------
225 cd /openils/var/web/xul
226 ln -sf rel_name/server server
227 ------------------------------------------------------------------------------
229 Change ownership of the Evergreen files
230 ---------------------------------------
232 All files in the `/openils/` directory and subdirectories must be owned by the
233 `opensrf` user. Issue the following command as the *root* Linux account to
234 change the ownership on the files:
237 ------------------------------------------------------------------------------
238 chown -R opensrf:opensrf /openils
239 ------------------------------------------------------------------------------
244 On Debian Stretch, run the following command as the root user:
247 ------------------------------------------------------------------------------
249 ------------------------------------------------------------------------------
251 Additional Instructions for Developers
252 --------------------------------------
255 Skip this section if you are using an official release tarball downloaded
256 from http://evergreen-ils.org/egdownloads
258 Developers working directly with the source code from the Git repository,
259 rather than an official release tarball, need to install the Dojo Toolkit
260 set of JavaScript libraries. The appropriate version of Dojo is included in
261 Evergreen release tarballs. Developers should install the Dojo 1.3.3 version
262 of Dojo by issuing the following commands as the *opensrf* Linux account:
265 ------------------------------------------------------------------------------
266 wget http://download.dojotoolkit.org/release-1.3.3/dojo-release-1.3.3.tar.gz
267 tar -C /openils/var/web/js -xzf dojo-release-1.3.3.tar.gz
268 cp -r /openils/var/web/js/dojo-release-1.3.3/* /openils/var/web/js/dojo/.
269 ------------------------------------------------------------------------------
272 Configure the Apache Web server
273 -------------------------------
275 . Use the example configuration files in `Open-ILS/examples/apache/` (for
276 Apache versions below 2.4) or `Open-ILS/examples/apache_24/` (for Apache
277 versions 2.4 or greater) to configure your Web server for the Evergreen
278 catalog, staff client, Web services, and administration interfaces. Issue the
279 following commands as the *root* Linux account:
283 ------------------------------------------------------------------------------
284 cp Open-ILS/examples/apache/eg.conf /etc/apache2/sites-available/
285 cp Open-ILS/examples/apache/eg_vhost.conf /etc/apache2/
286 cp Open-ILS/examples/apache/eg_startup /etc/apache2/
288 mkdir /etc/apache2/ssl
290 ------------------------------------------------------------------------------
292 .Ubuntu Trusty/Xenial and Debian Jessie/Stretch
294 ------------------------------------------------------------------------------------
295 cp Open-ILS/examples/apache_24/eg_24.conf /etc/apache2/sites-available/eg.conf
296 cp Open-ILS/examples/apache_24/eg_vhost_24.conf /etc/apache2/eg_vhost.conf
297 cp Open-ILS/examples/apache/eg_startup /etc/apache2/
299 mkdir /etc/apache2/ssl
301 ------------------------------------------------------------------------------------
303 . The `openssl` command cuts a new SSL key for your Apache server. For a
304 production server, you should purchase a signed SSL certificate, but you can
305 just use a self-signed certificate and accept the warnings in the staff client
306 and browser during testing and development. Create an SSL key for the Apache
307 server by issuing the following command as the *root* Linux account:
310 ------------------------------------------------------------------------------
311 openssl req -new -x509 -days 365 -nodes -out server.crt -keyout server.key
312 ------------------------------------------------------------------------------
314 . As the *root* Linux account, edit the `eg.conf` file that you copied into
316 a. To enable access to the offline upload / execute interface from any
317 workstation on any network, make the following change (and note that
318 you *must* secure this for a production instance):
319 * (Apache 2.2): Replace `Allow from 10.0.0.0/8` with `Allow from all`
320 * (Apache 2.4): Replace `Require host 10.0.0.0/8` with `Require all granted`
321 . Change the user for the Apache server.
322 * (Debian and Ubuntu): As the *root* Linux account, edit
323 `/etc/apache2/envvars`. Change `export APACHE_RUN_USER=www-data` to
324 `export APACHE_RUN_USER=opensrf`.
325 . As the *root* Linux account, configure Apache with KeepAlive settings
326 appropriate for Evergreen. Higher values can improve the performance of a
327 single client by allowing multiple requests to be sent over the same TCP
328 connection, but increase the risk of using up all available Apache child
329 processes and memory.
330 * (Debian and Ubuntu): Edit `/etc/apache2/apache2.conf`.
331 a. Change `KeepAliveTimeout` to `1`.
332 b. Change `MaxKeepAliveRequests` to `100`.
333 . As the *root* Linux account, configure the prefork module to start and keep
334 enough Apache servers available to provide quick responses to clients without
335 running out of memory. The following settings are a good starting point for a
336 site that exposes the default Evergreen catalogue to the web:
338 .Debian Wheezy (`/etc/apache2/apache2.conf`)
340 ------------------------------------------------------------------------------
341 <IfModule mpm_prefork_module>
346 MaxRequestsPerChild 500
348 ------------------------------------------------------------------------------
350 .Ubuntu Trusty/Xenial, Debian Jessie/Stretch (`/etc/apache2/mods-available/mpm_prefork.conf`)
352 ------------------------------------------------------------------------------
353 <IfModule mpm_prefork_module>
358 MaxConnectionsPerChild 500
360 ------------------------------------------------------------------------------
362 . (Ubuntu Trusty/Xenial, Debian Jessie/Stretch) As the *root* user,
363 enable the mpm_prefork module:
366 ------------------------------------------------------------------------------
369 ------------------------------------------------------------------------------
371 . (Debian Wheezy): As the *root* Linux account, enable the Evergreen site:
374 ------------------------------------------------------------------------------
375 a2dissite default # OPTIONAL: disable the default site (the "It Works" page)
377 ------------------------------------------------------------------------------
379 (Ubuntu Trusty/Xenial, Debian Jessie/Stretch):
382 ------------------------------------------------------------------------------
383 a2dissite 000-default # OPTIONAL: disable the default site (the "It Works" page)
385 ------------------------------------------------------------------------------
387 . (Debian and Ubuntu): As the *root* Linux account, enable Apache to write
388 to the lock directory; this is currently necessary because Apache
389 is running as the `opensrf` user:
392 ------------------------------------------------------------------------------
393 chown opensrf /var/lock/apache2
394 ------------------------------------------------------------------------------
396 Learn more about additional Apache options in the following sections:
398 * <<_apache_rewrite_tricks,Apache Rewrite Tricks>>
399 * <<_apache_access_handler_perl_module,Apache Access Handler Perl Module>>
401 Configure OpenSRF for the Evergreen application
402 -----------------------------------------------
403 There are a number of example OpenSRF configuration files in `/openils/conf/`
404 that you can use as a template for your Evergreen installation. Issue the
405 following commands as the *opensrf* Linux account:
408 ------------------------------------------------------------------------------
409 cp -b /openils/conf/opensrf_core.xml.example /openils/conf/opensrf_core.xml
410 cp -b /openils/conf/opensrf.xml.example /openils/conf/opensrf.xml
411 ------------------------------------------------------------------------------
413 When you installed OpenSRF, you created four Jabber users on two
414 separate domains and edited the `opensrf_core.xml` file accordingly. Please
415 refer back to the OpenSRF README and, as the *opensrf* Linux account, edit the
416 Evergreen version of the `opensrf_core.xml` file using the same Jabber users
417 and domains as you used while installing and testing OpenSRF.
420 The `-b` flag tells the `cp` command to create a backup version of the
421 destination file. The backup version of the destination file has a tilde (`~`)
422 appended to the file name, so if you have forgotten the Jabber users and
423 domains, you can retrieve the settings from the backup version of the files.
425 `eg_db_config`, described in <<_creating_the_evergreen_database,Creating the Evergreen
426 database>>, sets the database connection information in `opensrf.xml` for you.
428 Configure action triggers for the Evergreen application
429 -------------------------------------------------------
430 _Action Triggers_ provide hooks for the system to perform actions when a given
431 event occurs; for example, to generate reminder or overdue notices, the
432 `checkout.due` hook is processed and events are triggered for potential actions
433 if there is no checkin time.
435 To enable the default set of hooks, issue the following command as the
436 *opensrf* Linux account:
439 ------------------------------------------------------------------------------
440 cp -b /openils/conf/action_trigger_filters.json.example /openils/conf/action_trigger_filters.json
441 ------------------------------------------------------------------------------
443 For more information about configuring and running action triggers, see
444 <<_processing_action_triggers,Notifications / Action Triggers>>.
446 Creating the Evergreen database
447 -------------------------------
449 Setting up the PostgreSQL server
450 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
452 For production use, most libraries install the PostgreSQL database server on a
453 dedicated machine. Therefore, by default, the `Makefile.install` prerequisite
454 installer does *not* install the PostgreSQL 9 database server that is required
455 by every Evergreen system. You can install the packages required by Debian or
456 Ubuntu on the machine of your choice using the following commands as the
457 *root* Linux account:
459 .(Debian / Ubuntu) Installing PostgreSQL server packages
461 Each OS build target provides the postgres server installation packages
462 required for each operating system. To install Postgres server packages,
463 use the make target 'postgres-server-<OSTYPE>'. Choose the most appropriate
464 command below based on your operating system.
467 ------------------------------------------------------------------------------
468 make -f Open-ILS/src/extras/Makefile.install postgres-server-debian-stretch
469 make -f Open-ILS/src/extras/Makefile.install postgres-server-debian-jessie
470 make -f Open-ILS/src/extras/Makefile.install postgres-server-debian-wheezy
471 make -f Open-ILS/src/extras/Makefile.install postgres-server-ubuntu-trusty
472 make -f Open-ILS/src/extras/Makefile.install postgres-server-ubuntu-xenial
473 ------------------------------------------------------------------------------
475 For a standalone PostgreSQL server, install the following Perl modules for your
476 distribution as the *root* Linux account:
479 No extra modules required for these distributions.
481 You need to create a PostgreSQL superuser to create and access the database.
482 Issue the following command as the *postgres* Linux account to create a new
483 PostgreSQL superuser named `evergreen`. When prompted, enter the new user's
487 ------------------------------------------------------------------------------
488 createuser -s -P evergreen
489 ------------------------------------------------------------------------------
491 .Enabling connections to the PostgreSQL database
493 Your PostgreSQL database may be configured by default to prevent connections,
494 for example, it might reject attempts to connect via TCP/IP or from other
495 servers. To enable TCP/IP connections from localhost, check your `pg_hba.conf`
496 file, found in the `/etc/postgresql/` directory on Debian and Ubuntu.
497 A simple way to enable TCP/IP
498 connections from localhost to all databases with password authentication, which
499 would be suitable for a test install of Evergreen on a single server, is to
500 ensure the file contains the following entries _before_ any "host ... ident"
503 ------------------------------------------------------------------------------
504 host all all ::1/128 md5
505 host all all 127.0.0.1/32 md5
506 ------------------------------------------------------------------------------
508 When you change the `pg_hba.conf` file, you will need to reload PostgreSQL to
509 make the changes take effect. For more information on configuring connectivity
511 http://www.postgresql.org/docs/devel/static/auth-pg-hba-conf.html
513 Creating the Evergreen database and schema
514 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
516 Once you have created the *evergreen* PostgreSQL account, you also need to
517 create the database and schema, and configure your configuration files to point
518 at the database server. Issue the following command as the *root* Linux account
519 from inside the Evergreen source directory, replacing <user>, <password>,
520 <hostname>, <port>, and <dbname> with the appropriate values for your
521 PostgreSQL database (where <user> and <password> are for the *evergreen*
522 PostgreSQL account you just created), and replace <admin-user> and <admin-pass>
523 with the values you want for the *egadmin* Evergreen administrator account:
526 ------------------------------------------------------------------------------
527 perl Open-ILS/src/support-scripts/eg_db_config --update-config \
528 --service all --create-database --create-schema --create-offline \
529 --user <user> --password <password> --hostname <hostname> --port <port> \
530 --database <dbname> --admin-user <admin-user> --admin-pass <admin-pass>
531 ------------------------------------------------------------------------------
533 This creates the database and schema and configures all of the services in
534 your `/openils/conf/opensrf.xml` configuration file to point to that database.
535 It also creates the configuration files required by the Evergreen `cgi-bin`
536 administration scripts, and sets the user name and password for the *egadmin*
537 Evergreen administrator account to your requested values.
539 You can get a complete set of options for `eg_db_config` by passing the
544 If you add the `--load-all-sample` parameter to the `eg_db_config` command,
545 a set of authority and bibliographic records, call numbers, copies, staff
546 and regular users, and transactions will be loaded into your target
547 database. This sample dataset is commonly referred to as the _concerto_
548 sample data, and can be useful for testing out Evergreen functionality and
549 for creating problem reports that developers can easily recreate with their
550 own copy of the _concerto_ sample data.
552 Creating the database on a remote server
553 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
554 In a production instance of Evergreen, your PostgreSQL server should be
555 installed on a dedicated server.
557 PostgreSQL 9.4 and later
558 ^^^^^^^^^^^^^^^^^^^^^^^^
559 To create the database instance on a remote database server running PostgreSQL
560 9.4 or later, simply use the `--create-database` flag on `eg_db_config`.
564 1. As the *root* Linux account, start the `memcached` and `ejabberd` services
565 (if they aren't already running):
568 ------------------------------------------------------------------------------
569 /etc/init.d/ejabberd start
570 /etc/init.d/memcached start
571 ------------------------------------------------------------------------------
573 2. As the *opensrf* Linux account, start Evergreen. The `-l` flag in the
574 following command is only necessary if you want to force Evergreen to treat the
575 hostname as `localhost`; if you configured `opensrf.xml` using the real
576 hostname of your machine as returned by `perl -ENet::Domain 'print
577 Net::Domain::hostfqdn() . "\n";'`, you should not use the `-l` flag.
580 ------------------------------------------------------------------------------
581 osrf_control -l --start-all
582 ------------------------------------------------------------------------------
584 ** If you receive the error message `bash: osrf_control: command not found`,
585 then your environment variable `PATH` does not include the `/openils/bin`
586 directory; this should have been set in the *opensrf* Linux account's
587 `.bashrc` configuration file. To manually set the `PATH` variable, edit the
588 configuration file `~/.bashrc` as the *opensrf* Linux account and add the
592 ------------------------------------------------------------------------------
593 export PATH=$PATH:/openils/bin
594 ------------------------------------------------------------------------------
596 3. As the *opensrf* Linux account, generate the Web files needed by the staff
597 client and catalogue and update the organization unit proximity (you need to do
598 this the first time you start Evergreen, and after that each time you change the library org unit configuration.
602 ------------------------------------------------------------------------------
604 ------------------------------------------------------------------------------
606 4. As the *root* Linux account, restart the Apache Web server:
609 ------------------------------------------------------------------------------
610 /etc/init.d/apache2 restart
611 ------------------------------------------------------------------------------
613 If the Apache Web server was running when you started the OpenSRF services, you
614 might not be able to successfully log in to the OPAC or staff client until the
615 Apache Web server is restarted.
617 Testing connections to Evergreen
618 --------------------------------
620 Once you have installed and started Evergreen, test your connection to
621 Evergreen via `srfsh`. As the *opensrf* Linux account, issue the following
622 commands to start `srfsh` and try to log onto the Evergreen server using the
623 *egadmin* Evergreen administrator user name and password that you set using the
624 `eg_db_config` command:
627 ------------------------------------------------------------------------------
629 srfsh% login <admin-user> <admin-pass>
630 ------------------------------------------------------------------------------
632 You should see a result like:
634 Received Data: "250bf1518c7527a03249858687714376"
635 ------------------------------------
636 Request Completed Successfully
637 Request Time in seconds: 0.045286
638 ------------------------------------
642 "textcode":"SUCCESS",
645 "stacktrace":"oils_auth.c:304",
647 "authtoken":"e5f9827cc0f93b503a1cc66bee6bdd1a",
653 ------------------------------------
654 Request Completed Successfully
655 Request Time in seconds: 1.336568
656 ------------------------------------
657 [[install-troubleshooting-1]]
658 If this does not work, it's time to do some troubleshooting.
660 * As the *opensrf* Linux account, run the `settings-tester.pl` script to see
661 if it finds any system configuration problems. The script is found at
662 `Open-ILS/src/support-scripts/settings-tester.pl` in the Evergreen source
664 * Follow the steps in the http://evergreen-ils.org/dokuwiki/doku.php?id=troubleshooting:checking_for_errors[troubleshooting guide].
665 * If you have faithfully followed the entire set of installation steps
666 listed here, you are probably extremely close to a working system.
667 Gather your configuration files and log files and contact the
668 http://evergreen-ils.org/communicate/mailing-lists/[Evergreen development
669 mailing list] for assistance before making any drastic changes to your system
675 Need help installing or using Evergreen? Join the mailing lists at
676 http://evergreen-ils.org/communicate/mailing-lists/ or contact us on the Freenode
677 IRC network on the #evergreen channel.
681 This work is licensed under the Creative Commons Attribution-ShareAlike 3.0
682 Unported License. To view a copy of this license, visit
683 http://creativecommons.org/licenses/by-sa/3.0/ or send a letter to Creative
684 Commons, 444 Castro Street, Suite 900, Mountain View, California, 94041, USA.