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 .IP \[bu]
 194 MLBHRFreqXML.dtd
 195 .IP \[bu]
 196 MLBIntWalksXML.dtd
 197 .IP \[bu]
 198 MLBKORateXML.dtd
 199 .IP \[bu]
 200 mlbonbasepctxml.dtd
 201 .IP \[bu]
 202 MLBOPSXML.dtd
 203 .IP \[bu]
 204 MLBPlateAppsXML.dtd
 205 .IP \[bu]
 206 mlbrbisxml.dtd
 207 .IP \[bu]
 208 mlbrunsleadersxml.dtd
 209 .IP \[bu]
 210 MLBSacFliesXML.dtd
 211 .IP \[bu]
 212 MLBSacrificesXML.dtd
 213 .IP \[bu]
 214 MLBSBSuccessXML.dtd
 215 .IP \[bu]
 216 mlbsluggingpctxml.dtd
 217 .RE
 218 .P
 219 The GameInfo and SportInfo types do not have their own top-level
 220 tables in the database. Instead, their raw XML is stored in either the
 221 \(dqgame_info\(dq or \(dqsport_info\(dq table respectively.
 222
 223 .SH DATABASE SCHEMA
 224 .P
 225 At the top level (with two notable exceptions), we have one table for
 226 each of the XML document types that we import. For example, the
 227 documents corresponding to \fInewsxml.dtd\fR will have a table called
 228 \(dqnews\(dq. All top-level tables contain two important fields,
 229 \(dqxml_file_id\(dq and \(dqtime_stamp\(dq. The former is unique and
 230 prevents us from inserting the same data twice. The time stamp on the
 231 other hand lets us know when the data is old and can be removed. The
 232 database schema make it possible to delete only the outdated top-level
 233 records; all transient children should be removed by triggers.
 234 .P
 235 These top-level tables will often have children. For example, each
 236 news item has zero or more locations associated with it. The child
 237 table will be named <parent>_<children>, which in this case
 238 corresponds to \(dqnews_locations\(dq.
 239 .P
 240 To relate the two, a third table may exist with name
 241 <parent>__<child>. Note the two underscores. This prevents ambiguity
 242 when the child table itself contains underscores. The table joining
 243 \(dqnews\(dq with \(dqnews_locations\(dq is thus called
 244 \(dqnews__news_locations\(dq. This is necessary when the child table
 245 has a unique constraint; we don't want to blindly insert duplicate
 246 records keyed to the parent. Instead we'd like to use the third table
 247 to map an existing child to the new parent.
 248 .P
 249 Where it makes sense, children are kept unique to prevent pointless
 250 duplication. This slows down inserts, and speeds up reads (which are
 251 much more frequent). There is a tradeoff to be made, however. For a
 252 table with a small, fixed upper bound on the number of rows (like
 253 \(dqodds_casinos\(dq), there is great benefit to de-duplication. The
 254 total number of rows stays small, so inserts are still quick, and many
 255 duplicate rows are eliminated.
 256 .P
 257 But, with a table like \(dqodds_games\(dq, the number of games grows
 258 quickly and without bound. It is therefore more beneficial to be able
 259 to delete the old games (through an ON DELETE CASCADE, tied to
 260 \(dqodds\(dq) than it is to eliminate duplication. A table like
 261 \(dqnews_locations\(dq is somewhere in-between. It is hoped that the
 262 unique constraint in the top-level table's \(dqxml_file_id\(dq will
 263 prevent duplication in this case anyway.
 264 .P
 265 The aforementioned exceptions are the \(dqgame_info\(dq and
 266 \(dqsport_info\(dq tables. These tables contain the raw XML for a
 267 number of DTDs that are not handled individually. This is partially
 268 for backwards-compatibility with a legacy implementation, but is
 269 mostly a stopgap due to a lack of resources at the moment. These two
 270 tables (game_info and sport_info) still possess timestamps that allow
 271 us to prune old data.
 272 .P
 273 UML diagrams of the resulting database schema for each XML document
 274 type are provided with the \fBhtsn-import\fR documentation.
 275
 276 .SH XML Schema Oddities
 277 .P
 278 There are a number of problems with the XML on the wire. Even if we
 279 construct the DTDs ourselves, the results are sometimes
 280 inconsistent. Here we document a few of them.
 281
 282 .IP \[bu] 2
 283 Odds_XML.dtd
 284
 285 The <Notes> elements here are supposed to be associated with a set of
 286 <Game> elements, but since the pair
 287 (<Notes>...</Notes><Game>...</Game>) can appear zero or more times,
 288 this leads to ambiguity in parsing. We therefore ignore the notes
 289 entirely (although a hack is employed to facilitate parsing).
 290
 291 .IP \[bu]
 292 weatherxml.dtd
 293
 294 There appear to be two types of weather documents; the first has
 295 <listing> contained within <forecast> and the second has <forecast>
 296 contained within <listing>. While it would be possible to parse both,
 297 it would greatly complicate things. The first form is more common, so
 298 that's all we support for now.
 299
 300 .SH OPTIONS
 301
 302 .IP \fB\-\-backend\fR,\ \fB\-b\fR
 303 The RDBMS backend to use. Valid choices are \fISqlite\fR and
 304 \fIPostgres\fR. Capitalization is important, sorry.
 305
 306 Default: Sqlite
 307
 308 .IP \fB\-\-connection-string\fR,\ \fB\-c\fR
 309 The connection string used for connecting to the database backend
 310 given by the \fB\-\-backend\fR option. The default is appropriate for
 311 the \fISqlite\fR backend.
 312
 313 Default: \(dq:memory:\(dq
 314
 315 .IP \fB\-\-log-file\fR
 316 If you specify a file here, logs will be written to it (possibly in
 317 addition to syslog). Can be either a relative or absolute path. It
 318 will not be auto-rotated; use something like logrotate for that.
 319
 320 Default: none
 321
 322 .IP \fB\-\-log-level\fR
 323 How verbose should the logs be? We log notifications at four levels:
 324 DEBUG, INFO, WARN, and ERROR. Specify the \(dqmost boring\(dq level of
 325 notifications you would like to receive (in all-caps); more
 326 interesting notifications will be logged as well. The debug output is
 327 extremely verbose and will not be written to syslog even if you try.
 328
 329 Default: INFO
 330
 331 .IP \fB\-\-remove\fR,\ \fB\-r\fR
 332 Remove successfully processed files. If you enable this, you can see
 333 at a glance which XML files are not being processed, because they're
 334 all that should be left.
 335
 336 Default: disabled
 337
 338 .IP \fB\-\-syslog\fR,\ \fB\-s\fR
 339 Enable logging to syslog. On Windows this will attempt to communicate
 340 (over UDP) with a syslog daemon on localhost, which will most likely
 341 not work.
 342
 343 Default: disabled
 344
 345 .SH CONFIGURATION FILE
 346 .P
 347 Any of the command-line options mentioned above can be specified in a
 348 configuration file instead. We first look for \(dqhtsn-importrc\(dq in
 349 the system configuration directory. We then look for a file named
 350 \(dq.htsn-importrc\(dq in the user's home directory. The latter will
 351 override the former.
 352 .P
 353 The user's home directory is simply $HOME on Unix; on Windows it's
 354 wherever %APPDATA% points. The system configuration directory is
 355 determined by Cabal; the \(dqsysconfdir\(dq parameter during the
 356 \(dqconfigure\(dq step is used.
 357 .P
 358 The file's syntax is given by examples in the htsn-importrc.example file
 359 (included with \fBhtsn-import\fR).
 360 .P
 361 Options specified on the command-line override those in either
 362 configuration file.
 363
 364 .SH EXAMPLES
 365 .IP \[bu] 2
 366 Import newsxml.xml into a preexisting sqlite database named \(dqfoo.sqlite3\(dq:
 367
 368 .nf
 369 .I $ htsn-import --connection-string='foo.sqlite3' \\\\
 370 .I "              test/xml/newsxml.xml"
 371 Successfully imported test/xml/newsxml.xml.
 372 Imported 1 document(s) total.
 373 .fi
 374 .IP \[bu]
 375 Repeat the previous example, but delete newsxml.xml afterwards:
 376
 377 .nf
 378 .I $ htsn-import --connection-string='foo.sqlite3' \\\\
 379 .I "              --remove test/xml/newsxml.xml"
 380 Successfully imported test/xml/newsxml.xml.
 381 Imported 1 document(s) total.
 382 Removed processed file test/xml/newsxml.xml.
 383 .fi
 384 .IP \[bu]
 385 Use a Postgres database instead of the default Sqlite. This assumes
 386 that you have a database named \(dqhtsn\(dq accessible to user
 387 \(dqpostgres\(dq locally:
 388
 389 .nf
 390 .I $ htsn-import --connection-string='dbname=htsn user=postgres' \\\\
 391 .I "              --backend=Postgres test/xml/newsxml.xml"
 392 Successfully imported test/xml/newsxml.xml.
 393 Imported 1 document(s) total.
 394 .fi
 395
 396 .SH BUGS
 397
 398 .P
 399 Send bugs to michael@orlitzky.com.