README.dev

   1 = Setup PVE Development Environment =
   2
   3 1. Install Debian 'jessie'
   4 2. Configure pvetest repository in apt sources.list
   5
   6  deb http://download.proxmox.com/debian jessie pvetest
   7
   8 3. Add our repository key with apt-key:
   9
  10  wget -O- "http://download.proxmox.com/debian/key.asc" | apt-key add -
  11
  12 4. make sure you have a read IP address for your hostname in /etc/hosts
  13    (using 127.0.1.1 will not work)
  14
  15 5. run: apt-get update
  16 6. run: apt-get dist-upgrade
  17 7. run: apt-get install proxmox-ve-3.10.0
  18
  19 You should now have a working Proxmox VE installation.
  20
  21 = Install build prerequisites for development environment =
  22
  23 apt-get -y install build-essential git-core debhelper autotools-dev \
  24 autogen dh-autoreconf dkms doxygen check pkg-config groff quilt dpatch \
  25 automake autoconf libtool lintian libdevel-cycle-perl libjson-perl \
  26 libcommon-sense-perl liblinux-inotify2-perl libio-stringy-perl \
  27 libstring-shellquote-perl dh-systemd rpm2cpio libsqlite3-dev sqlite3 \
  28 libglib2.0-dev librrd-dev librrds-perl rrdcached libdigest-hmac-perl \
  29 libxml-parser-perl gdb libcrypt-openssl-random-perl \
  30 libcrypt-openssl-rsa-perl libnet-ldap-perl libauthen-pam-perl \
  31 libjson-xs-perl libterm-readline-gnu-perl oathtool libmime-base32-perl \
  32 liboath0 libpci-dev texi2html libsdl1.2-dev libgnutls28-dev \
  33 libspice-protocol-dev xfslibs-dev libnuma-dev libaio-dev \
  34 pve-libspice-server-dev libusbredirparser-dev glusterfs-common \
  35 libusb-1.0-0-dev librbd-dev libpopt-dev iproute bridge-utils numactl \
  36 glusterfs-common ceph-common python-ceph libgoogle-perftools4 \
  37 libfile-chdir-perl lvm2 glusterfs-client liblockfile-simple-perl \
  38 libsystemd-daemon-dev libreadline-gplv2-dev libio-multiplex-perl \
  39 libnetfilter-log-dev libipset3 ipset socat libsasl2-dev libogg-dev \
  40 python-pyparsing libfilesys-df-perl libcrypt-ssleay-perl \
  41 libfile-readbackwards-perl libanyevent-perl libanyevent-http-perl \
  42 unzip liblocale-po-perl vlan ifenslave-2.6 libfile-sync-perl cstream \
  43 lzop dtach apt-transport-https hdparm gdisk parted ttf-dejavu-core \
  44 liblzma-dev dosfstools mtools libxen-dev
  45
  46 = Compile PVE packages from Source =
  47
  48 Download and install the following git modules in order from top to bottom:
  49
  50 # git clone git://git.proxmox.com/git/<PACKAGE.git>
  51
  52 You currently need the following packages:
  53
  54 libqb.git
  55 corosync-pve.git
  56 pve-common.git
  57 pve-cluster.git
  58 lvm.git
  59 pve-access-control.git
  60 pve-storage.git
  61 pve-qemu-kvm.git
  62 qemu-server.git
  63 vncterm.git
  64 spiceterm.git
  65 #vzquota.git
  66 #vzctl.git
  67 #fence-agents-pve.git
  68 #resource-agents-pve.git
  69 pve-manager.git
  70 pve-kernel-3.10.0.git
  71 libiscsi.git
  72 #gfs2-utils.git
  73 ksm-control-daemon.git
  74
  75 Most packages can be installed with 'make dinstall' command.
  76
  77 4.  Reboot the system.
  78 5.  Learn to use the quilt patch scripts.
  79 6.  Happy coding.
  80
  81 There is an experimental package containing the API documentation
  82 as ExtJS application:
  83
  84 pve2-api-doc.git
  85
  86 You can view the source code at:
  87
  88 https://git.proxmox.com
  89
  90
  91 = REST vs. SOAP =
  92
  93 We decided to change our SOAP API (1.X) and use a REST like API. The
  94 concept is described in [1] (Resource Oriented Architecture
  95 (ROA)). The main advantage is that we are able to remove a lot of code
  96 (the whole SOAP stack) to reduce software complexity.
  97
  98 We also moved away from server side content generation. Instead we use
  99 the ExtJS Rich Internet Application Framework
 100 (http://www.sencha.com).
 101
 102 That framework, like any other AJAX toolkit, can talk directly to the
 103 REST API using JSON. So we were able to remove the server side
 104 template toolkit completely.
 105
 106 = JSON and JSON Schema =
 107
 108 We use JSON as data format, because it is simple and parse-able by any
 109 web browser.
 110
 111 Additionally, we use JSON Schema [2] to formally describe our API. So
 112 we can automatically generate the whole API Documentation, and we can
 113 verify all parameters and return values.
 114
 115 A great side effect was that we are able to use JSON Schema to
 116 produce command line argument parsers automatically. In fact, the REST
 117 API and the command line tools use the same code.
 118
 119 Object linkage is done using the JSON Hyper Schema (links property).
 120
 121 A small utility called 'pvesh' exposes the whole REST API on the command
 122 line.
 123
 124 So here is a summary of the advantage:
 125
 126    - easy, human readable data format (native web browser format)
 127    - automatic parameter verification (we can also verify return values)
 128    - automatic generation of API documentation
 129    - easy way to create command line tools (using same API).
 130
 131 = API Implementation (PVE::RESTHandler) =
 132
 133 All classes exposing methods on the API use PVE::RESTHandler as base class.
 134
 135   use base qw(PVE::RESTHandler);
 136
 137 To expose methods, one needs to call register_method():
 138
 139   __PACKAGE__->register_method ($schema);
 140
 141 Where $schema is a PVE method schema as described in
 142 PVE::JSONSchema. It includes a description of parameters and return
 143 values, and a reference to the actual code
 144
 145 __PACKAGE__->register_method ({
 146     name => 'echo',
 147     path => 'echo',
 148     method => 'GET',
 149     description => "simple return value of parameter 'text'",
 150     parameters => {
 151         additionalProperties => 0,
 152         properties => {
 153             text => {
 154                  type => 'string',
 155             }
 156         },
 157     },
 158     returns => {
 159         type => 'string',
 160     },
 161     code => sub {
 162         my ($conn, $resp, $param) = @_;
 163
 164         return $param->{text};
 165     }
 166 });
 167
 168 The 'name' property is only used if you want to call the method
 169 directly from Perl. You can do that using:
 170
 171   print __PACKAGE__->echo({ text => "a test" });
 172
 173 We use Perl's AUTOLOAD feature to implement this. Note: You need to
 174 pass parameters a HASH reference.
 175
 176 There is a special helper method called cli_handler(). This is used by
 177 the CLIHandler Class for command line tools, where you want to pass
 178 arguments as array of strings. This uses Getopt::Long to parse parameters.
 179
 180 There is a second way to map names to methods - using the 'path'
 181 property.  And you can register subclasses. That way you can set up a
 182 filesystem like hierarchy to access methods.
 183
 184 Here is an example:
 185 ----------------------------
 186 package C1;
 187
 188 __PACKAGE__->register_method ({
 189     subclass => "C2",
 190     path => 'sub2',
 191 });
 192
 193
 194 __PACKAGE__->register_method ({
 195     name => 'list1',
 196     path => 'index',
 197     method => 'GET',
 198     ...
 199 });
 200
 201 package C2;
 202
 203 __PACKAGE__->register_method ({
 204     name => 'list2',
 205     path => 'index',
 206     method => 'GET',
 207     ...
 208 });
 209 -------------------------------
 210
 211 The utily method find_handler (in PVE::RESTHandler) can be use to do
 212 'path' related method lookups.
 213
 214 C1->find_handler('GET', "/index")      => C1::list1
 215 C1->find_handler('GET', "/sub2/index") => C2::list2
 216
 217 The HTTP server use the URL (a path) to find the corresponding method.
 218
 219
 220 = References =
 221
 222 [1] RESTful Web Services
 223 Web services for the real world
 224
 225 By
 226     Leonard Richardson, Sam Ruby
 227 Publisher:
 228     O'Reilly Media
 229 Released:
 230     May 2007
 231
 232 [2] JSON Schema links: http://json-schema.org/