doc/man1/htsn-import.1

   1 .TH htsn-import 1
   2
   3 .SH NAME
   4 htsn-import \- Import XML files from The Sports Network into an RDBMS.
   5
   6 .SH SYNOPSIS
   7
   8 \fBhtsn-import\fR [OPTIONS] [FILES]
   9
  10 .SH DESCRIPTION
  11 .P
  12 The Sports Network <http://www.sportsnetwork.com/> offers an XML feed
  13 containing various sports news and statistics. Our sister program
  14 \fBhtsn\fR is capable of retrieving the feed and saving the individual
  15 XML documents contained therein. But what to do with them?
  16 .P
  17 The purpose of \fBhtsn-import\fR is to take these XML documents and
  18 get them into something we can use, a relational database management
  19 system (RDBMS), otherwise known as a SQL database. The structure of
  20 relational database, is, well, relational, and the feed XML is not. So
  21 there is some work to do before the data can be imported into the
  22 database.
  23 .P
  24 First, we must parse the XML. Each supported document type (see below)
  25 has a full pickle/unpickle implementation (\(dqpickle\(dq is simply a
  26 synonym for serialize here). That means that we parse the entire
  27 document into a data structure, and if we pickle (serialize) that data
  28 structure, we get the exact same XML document tha we started with.
  29 .P
  30 This is important for two reasons. First, it serves as a second level
  31 of validation. The first validation is performed by the XML parser,
  32 but if that succeeds and unpicking fails, we know that something is
  33 fishy. Second, we don't ever want to be surprised by some new element
  34 or attribute showing up in the XML. The fact that we can unpickle the
  35 whole thing now means that we won't be surprised in the future.
  36 .P
  37 The aforementioned feature is especially important because we
  38 automatically migrate the database schema every time we import a
  39 document. If you attempt to import a \(dqnewsxml.dtd\(dq document, all
  40 database objects relating to the news will be created if they do not
  41 exist. We don't want the schema to change out from under us without
  42 warning, so it's important that no XML be parsed that would result in
  43 a different schema than we had previously. Since we can
  44 pickle/unpickle everything already, this should be impossible.
  45
  46 .SH SUPPORTED DOCUMENT TYPES
  47 .P
  48 The XML document types obtained from the feed are uniquely identified
  49 by their DTDs. We currently support documents with the following DTDs:
  50 .IP \[bu] 2
  51 AutoRacingResultsXML.dtd
  52 .IP \[bu]
  53 Auto_Racing_Schedule_XML.dtd
  54 .IP \[bu]
  55 Heartbeat.dtd
  56 .IP \[bu]
  57 Injuries_Detail_XML.dtd
  58 .IP \[bu]
  59 injuriesxml.dtd
  60 .IP \[bu]
  61 newsxml.dtd
  62 .IP \[bu]
  63 Odds_XML.dtd
  64 .IP \[bu]
  65 scoresxml.dtd
  66 .IP \[bu]
  67 weatherxml.dtd
  68 .IP \[bu]
  69 GameInfo
  70 .RS
  71 .IP \[bu]
  72 CBASK_Lineup_XML.dtd
  73 .IP \[bu]
  74 cbaskpreviewxml.dtd
  75 .IP \[bu]
  76 cflpreviewxml.dtd
  77 .IP \[bu]
  78 Matchup_NBA_NHL_XML.dtd
  79 .IP \[bu]
  80 MLB_Gaming_Matchup_XML.dtd
  81 .IP \[bu]
  82 MLB_Lineup_XML.dtd
  83 .IP \[bu]
  84 MLB_Matchup_XML.dtd
  85 .IP \[bu]
  86 MLS_Preview_XML.dtd
  87 .IP \[bu]
  88 mlbpreviewxml.dtd
  89 .IP \[bu]
  90 NBA_Gaming_Matchup_XML.dtd
  91 .IP \[bu]
  92 NBA_Playoff_Matchup_XML.dtd
  93 .IP \[bu]
  94 NBALineupXML.dtd
  95 .IP \[bu]
  96 nbapreviewxml.dtd
  97 .IP \[bu]
  98 NCAA_FB_Preview_XML.dtd
  99 .IP \[bu]
 100 NFL_NCAA_FB_Matchup_XML.dtd
 101 .IP \[bu]
 102 nflpreviewxml.dtd
 103 .IP \[bu]
 104 nhlpreviewxml.dtd
 105 .IP \[bu]
 106 recapxml.dtd
 107 .IP \[bu]
 108 WorldBaseballPreviewXML.dtd
 109 .RE
 110 .IP \[bu]
 111 SportInfo
 112 .RS
 113 .IP \[bu]
 114 CBASK_3PPctXML.dtd
 115 .IP \[bu]
 116 Cbask_All_Tourn_Teams_XML.dtd
 117 .IP \[bu]
 118 CBASK_AssistsXML.dtd
 119 .IP \[bu]
 120 Cbask_Awards_XML.dtd
 121 .IP \[bu]
 122 CBASK_BlocksXML.dtd
 123 .IP \[bu]
 124 Cbask_Conf_Standings_XML.dtd
 125 .IP \[bu]
 126 Cbask_DivII_III_Indv_Stats_XML.dtd
 127 .IP \[bu]
 128 Cbask_DivII_Team_Stats_XML.dtd
 129 .IP \[bu]
 130 Cbask_DivIII_Team_Stats_XML.dtd
 131 .IP \[bu]
 132 CBASK_FGPctXML.dtd
 133 .IP \[bu]
 134 CBASK_FoulsXML.dtd
 135 .IP \[bu]
 136 CBASK_FTPctXML.dtd
 137 .IP \[bu]
 138 Cbask_Indv_Scoring_XML.dtd
 139 .IP \[bu]
 140 CBASK_MinutesXML.dtd
 141 .IP \[bu]
 142 Cbask_Polls_XML.dtd
 143 .IP \[bu]
 144 CBASK_ReboundsXML.dtd
 145 .IP \[bu]
 146 CBASK_ScoringLeadersXML.dtd
 147 .IP \[bu]
 148 Cbask_Team_ThreePT_Made_XML.dtd
 149 .IP \[bu]
 150 Cbask_Team_ThreePT_PCT_XML.dtd
 151 .IP \[bu]
 152 Cbask_Team_Win_Pct_XML.dtd
 153 .IP \[bu]
 154 Cbask_Top_Twenty_Five_XML.dtd
 155 .IP \[bu]
 156 CBASK_TopTwentyFiveResult_XML.dtd
 157 .IP \[bu]
 158 Cbask_Tourn_Awards_XML.dtd
 159 .IP \[bu]
 160 Cbask_Tourn_Champs_XML.dtd
 161 .IP \[bu]
 162 Cbask_Tourn_Indiv_XML.dtd
 163 .IP \[bu]
 164 Cbask_Tourn_Leaders_XML.dtd
 165 .IP \[bu]
 166 Cbask_Tourn_MVP_XML.dtd
 167 .IP \[bu]
 168 Cbask_Tourn_Records_XML.dtd
 169 .IP \[bu]
 170 LeagueScheduleXML.dtd
 171 .IP \[bu]
 172 minorscoresxml.dtd
 173 .IP \[bu]
 174 Minor_Baseball_League_Leaders_XML.dtd
 175 .IP \[bu]
 176 Minor_Baseball_Standings_XML.dtd
 177 .IP \[bu]
 178 Minor_Baseball_Transactions_XML.dtd
 179 .IP \[bu]
 180 mlbbattingavgxml.dtd
 181 .IP \[bu]
 182 mlbdoublesleadersxml.dtd
 183 .IP \[bu]
 184 MLBGamesPlayedXML.dtd
 185 .IP \[bu]
 186 MLBGIDPXML.dtd
 187 .IP \[bu]
 188 MLBHitByPitchXML.dtd
 189 .IP \[bu]
 190 mlbhitsleadersxml.dtd
 191 .IP \[bu]
 192 mlbhomerunsxml.dtd
 193 .RE
 194 .P
 195 The GameInfo and SportInfo types do not have their own top-level
 196 tables in the database. Instead, their raw XML is stored in either the
 197 \(dqgame_info\(dq or \(dqsport_info\(dq table respectively.
 198
 199 .SH DATABASE SCHEMA
 200 .P
 201 At the top level (with two notable exceptions), we have one table for
 202 each of the XML document types that we import. For example, the
 203 documents corresponding to \fInewsxml.dtd\fR will have a table called
 204 \(dqnews\(dq. All top-level tables contain two important fields,
 205 \(dqxml_file_id\(dq and \(dqtime_stamp\(dq. The former is unique and
 206 prevents us from inserting the same data twice. The time stamp on the
 207 other hand lets us know when the data is old and can be removed. The
 208 database schema make it possible to delete only the outdated top-level
 209 records; all transient children should be removed by triggers.
 210 .P
 211 These top-level tables will often have children. For example, each
 212 news item has zero or more locations associated with it. The child
 213 table will be named <parent>_<children>, which in this case
 214 corresponds to \(dqnews_locations\(dq.
 215 .P
 216 To relate the two, a third table may exist with name
 217 <parent>__<child>. Note the two underscores. This prevents ambiguity
 218 when the child table itself contains underscores. The table joining
 219 \(dqnews\(dq with \(dqnews_locations\(dq is thus called
 220 \(dqnews__news_locations\(dq. This is necessary when the child table
 221 has a unique constraint; we don't want to blindly insert duplicate
 222 records keyed to the parent. Instead we'd like to use the third table
 223 to map an existing child to the new parent.
 224 .P
 225 Where it makes sense, children are kept unique to prevent pointless
 226 duplication. This slows down inserts, and speeds up reads (which are
 227 much more frequent). There is a tradeoff to be made, however. For a
 228 table with a small, fixed upper bound on the number of rows (like
 229 \(dqodds_casinos\(dq), there is great benefit to de-duplication. The
 230 total number of rows stays small, so inserts are still quick, and many
 231 duplicate rows are eliminated.
 232 .P
 233 But, with a table like \(dqodds_games\(dq, the number of games grows
 234 quickly and without bound. It is therefore more beneficial to be able
 235 to delete the old games (through an ON DELETE CASCADE, tied to
 236 \(dqodds\(dq) than it is to eliminate duplication. A table like
 237 \(dqnews_locations\(dq is somewhere in-between. It is hoped that the
 238 unique constraint in the top-level table's \(dqxml_file_id\(dq will
 239 prevent duplication in this case anyway.
 240 .P
 241 The aforementioned exceptions are the \(dqgame_info\(dq and
 242 \(dqsport_info\(dq tables. These tables contain the raw XML for a
 243 number of DTDs that are not handled individually. This is partially
 244 for backwards-compatibility with a legacy implementation, but is
 245 mostly a stopgap due to a lack of resources at the moment. These two
 246 tables (game_info and sport_info) still possess timestamps that allow
 247 us to prune old data.
 248 .P
 249 UML diagrams of the resulting database schema for each XML document
 250 type are provided with the \fBhtsn-import\fR documentation.
 251
 252 .SH XML Schema Oddities
 253 .P
 254 There are a number of problems with the XML on the wire. Even if we
 255 construct the DTDs ourselves, the results are sometimes
 256 inconsistent. Here we document a few of them.
 257
 258 .IP \[bu] 2
 259 Odds_XML.dtd
 260
 261 The <Notes> elements here are supposed to be associated with a set of
 262 <Game> elements, but since the pair
 263 (<Notes>...</Notes><Game>...</Game>) can appear zero or more times,
 264 this leads to ambiguity in parsing. We therefore ignore the notes
 265 entirely (although a hack is employed to facilitate parsing).
 266
 267 .IP \[bu]
 268 weatherxml.dtd
 269
 270 There appear to be two types of weather documents; the first has
 271 <listing> contained within <forecast> and the second has <forecast>
 272 contained within <listing>. While it would be possible to parse both,
 273 it would greatly complicate things. The first form is more common, so
 274 that's all we support for now.
 275
 276 .SH OPTIONS
 277
 278 .IP \fB\-\-backend\fR,\ \fB\-b\fR
 279 The RDBMS backend to use. Valid choices are \fISqlite\fR and
 280 \fIPostgres\fR. Capitalization is important, sorry.
 281
 282 Default: Sqlite
 283
 284 .IP \fB\-\-connection-string\fR,\ \fB\-c\fR
 285 The connection string used for connecting to the database backend
 286 given by the \fB\-\-backend\fR option. The default is appropriate for
 287 the \fISqlite\fR backend.
 288
 289 Default: \(dq:memory:\(dq
 290
 291 .IP \fB\-\-log-file\fR
 292 If you specify a file here, logs will be written to it (possibly in
 293 addition to syslog). Can be either a relative or absolute path. It
 294 will not be auto-rotated; use something like logrotate for that.
 295
 296 Default: none
 297
 298 .IP \fB\-\-log-level\fR
 299 How verbose should the logs be? We log notifications at four levels:
 300 DEBUG, INFO, WARN, and ERROR. Specify the \(dqmost boring\(dq level of
 301 notifications you would like to receive (in all-caps); more
 302 interesting notifications will be logged as well. The debug output is
 303 extremely verbose and will not be written to syslog even if you try.
 304
 305 Default: INFO
 306
 307 .IP \fB\-\-remove\fR,\ \fB\-r\fR
 308 Remove successfully processed files. If you enable this, you can see
 309 at a glance which XML files are not being processed, because they're
 310 all that should be left.
 311
 312 Default: disabled
 313
 314 .IP \fB\-\-syslog\fR,\ \fB\-s\fR
 315 Enable logging to syslog. On Windows this will attempt to communicate
 316 (over UDP) with a syslog daemon on localhost, which will most likely
 317 not work.
 318
 319 Default: disabled
 320
 321 .SH CONFIGURATION FILE
 322 .P
 323 Any of the command-line options mentioned above can be specified in a
 324 configuration file instead. We first look for \(dqhtsn-importrc\(dq in
 325 the system configuration directory. We then look for a file named
 326 \(dq.htsn-importrc\(dq in the user's home directory. The latter will
 327 override the former.
 328 .P
 329 The user's home directory is simply $HOME on Unix; on Windows it's
 330 wherever %APPDATA% points. The system configuration directory is
 331 determined by Cabal; the \(dqsysconfdir\(dq parameter during the
 332 \(dqconfigure\(dq step is used.
 333 .P
 334 The file's syntax is given by examples in the htsn-importrc.example file
 335 (included with \fBhtsn-import\fR).
 336 .P
 337 Options specified on the command-line override those in either
 338 configuration file.
 339
 340 .SH EXAMPLES
 341 .IP \[bu] 2
 342 Import newsxml.xml into a preexisting sqlite database named \(dqfoo.sqlite3\(dq:
 343
 344 .nf
 345 .I $ htsn-import --connection-string='foo.sqlite3' \\\\
 346 .I "              test/xml/newsxml.xml"
 347 Successfully imported test/xml/newsxml.xml.
 348 Imported 1 document(s) total.
 349 .fi
 350 .IP \[bu]
 351 Repeat the previous example, but delete newsxml.xml afterwards:
 352
 353 .nf
 354 .I $ htsn-import --connection-string='foo.sqlite3' \\\\
 355 .I "              --remove test/xml/newsxml.xml"
 356 Successfully imported test/xml/newsxml.xml.
 357 Imported 1 document(s) total.
 358 Removed processed file test/xml/newsxml.xml.
 359 .fi
 360 .IP \[bu]
 361 Use a Postgres database instead of the default Sqlite. This assumes
 362 that you have a database named \(dqhtsn\(dq accessible to user
 363 \(dqpostgres\(dq locally:
 364
 365 .nf
 366 .I $ htsn-import --connection-string='dbname=htsn user=postgres' \\\\
 367 .I "              --backend=Postgres test/xml/newsxml.xml"
 368 Successfully imported test/xml/newsxml.xml.
 369 Imported 1 document(s) total.
 370 .fi
 371
 372 .SH BUGS
 373
 374 .P
 375 Send bugs to michael@orlitzky.com.