journal: finishing postgres adapter

1 files changed, 115 insertions, 1 deletions

diff --git a/lib/rbot/journal/postgres.rb b/lib/rbot/journal/postgres.rb
index 85514fb2..57c539a7 100644
--- a/lib/rbot/journal/postgres.rb
+++ b/lib/rbot/journal/postgres.rb
@@ -5,12 +5,20 @@
 # :title: journal backend for postgresql
 
 require 'pg'
+require 'json'
 
 module Irc
 class Bot
 module Journal
+
+  class Query
+  end
+
   module Storage
+
     class PostgresStorage < AbstractStorage
+      attr_reader :conn
+
       def initialize(opts={})
         @uri = opts[:uri] || 'postgresql://localhost/rbot_journal'
         @conn = PG.connect(@uri)
@@ -25,12 +33,118 @@ module Journal
             'PostgreSQL Version too old: %s, supported: >= 9.3' % [@version])
         end
         @jsonb = (version >= 940)
-        log 'journal storage: no jsonb support, consider upgrading postgres'
+        log 'journal storage: no jsonb support, consider upgrading postgres' unless @jsonb
 
+        drop if opts[:drop]
         create_table
       end
 
       def create_table
+        @conn.exec('
+          CREATE TABLE IF NOT EXISTS journal
+            (id UUID PRIMARY KEY,
+             topic TEXT NOT NULL,
+             timestamp TIMESTAMP WITH TIME ZONE NOT NULL,
+             payload %s NOT NULL)' % [@jsonb ? 'JSONB' : 'JSON'])
+      end
+
+      def insert(m)
+        @conn.exec_params('INSERT INTO journal VALUES ($1, $2, $3, $4);',
+          [m.id, m.topic, m.timestamp, JSON.generate(m.payload)])
+      end
+
+      def find(query, limit=100, offset=0)
+        sql, params = query_to_sql(query)
+        sql = 'SELECT * FROM journal WHERE ' + sql + ' LIMIT %d OFFSET %d' % [limit.to_i, offset.to_i]
+        res = @conn.exec_params(sql, params)
+        res.map do |row|
+          timestamp = DateTime.strptime(row['timestamp'], '%Y-%m-%d %H:%M:%S%z')
+          JournalMessage.new(id: row['id'], timestamp: timestamp,
+            topic: row['topic'], payload: JSON.parse(row['payload']))
+        end
+      end
+
+      # returns the number of messages that match the query
+      def count(query)
+        sql, params = query_to_sql(query)
+        sql = 'SELECT COUNT(*) FROM journal WHERE ' + sql
+        res = @conn.exec_params(sql, params)
+        res[0]['count'].to_i
+      end
+
+      def drop
+        @conn.exec('DROP TABLE journal;') rescue nil
+      end
+
+      def query_to_sql(query)
+        params = []
+        placeholder = Proc.new do |value|
+          params << value
+          '$%d' % [params.length]
+        end
+        sql = {op: 'AND', list: []}
+
+        # ID query OR condition
+        unless query.id.empty?
+          sql[:list] << {
+            op: 'OR',
+            list: query.id.map { |id| 
+              'id = ' + placeholder.call(id)
+            }
+          }
+        end
+
+        # Topic query OR condition
+        unless query.topic.empty?
+          sql[:list] << {
+            op: 'OR',
+            list: query.topic.map { |topic| 
+              'topic ILIKE ' + placeholder.call(topic.gsub('*', '%'))
+            }
+          }
+        end
+
+        # Timestamp range query AND condition
+        if query.timestamp[:from] or query.timestamp[:to]
+          list = []
+          if query.timestamp[:from]
+            list << 'timestamp >= ' + placeholder.call(query.timestamp[:from])
+          end
+          if query.timestamp[:to]
+            list << 'timestamp <= ' + placeholder.call(query.timestamp[:to])
+          end
+          sql[:list] << {
+            op: 'AND',
+            list: list
+          }
+        end
+
+        # Payload query
+        unless query.payload.empty?
+          list = []
+          query.payload.each_pair do |key, value|
+            selector = 'payload'
+            k = key.to_s.split('.')
+            k.each_index { |i|
+              if i >= k.length-1
+                selector += '->>\'%s\'' % [@conn.escape_string(k[i])]
+              else
+                selector += '->\'%s\'' % [@conn.escape_string(k[i])]
+              end
+            }
+            list << selector + ' = ' + placeholder.call(value)
+          end
+          sql[:list] << {
+            op: 'OR',
+            list: list
+          }
+        end
+
+        sql = sql[:list].map { |stmt|
+          '(' + stmt[:list].join(' %s ' % [stmt[:op]]) + ')'
+        }.join(' %s ' % [sql[:op]])
+
+        [sql, params]
       end
     end
   end