massive improvmenets.

README.md

@@ -16,8 +16,8 @@ Simple presto-db connector using nim. (Still under heavy development.)
 ## Usage:
 
 ```nim
- import presto
- let con = connect("host", 8889, "hive", "default", "benny")
+ import db_presto
+ let con = open("host", 8889, "hive", "default", "benny")
  defer: con.close()
  var cur = con.cursor()
  cur.execute("SELECT NOW()")
@@ -37,4 +37,5 @@ I'll be happy to get any help, just work & pull request.
 
 
 ## TODO:
-* A lot of tests.
+* Table coursor.
+* Tests.

presto.nim → db_presto.nim

@@ -16,7 +16,9 @@ proc range(size: int): seq[int] =
 
 type NoConnectionError = object of Exception
 type CursorError = object of Exception
+type QueryExecutionError = object of Exception
 type NoTransactionError = object of Exception
+type NotValidProtocolError = object of Exception
 
 type
  ResultSet = ref object
@@ -32,18 +34,28 @@ type
  schema: string
  source: string
  sessionProps: string
- poolInterval: string
+ poolInterval: int
  username: string
+ tableCursor: bool
  host: string
+ protocol: string
  port: string
  resultSet: ResultSet
 
 type
  Connection = ref object of RootObj
  host: string
  port: int
+ timeOutInSeconds: int
  cur: Cursor
 
+proc ping(this: Connection): bool =
+ var client = newHttpClient(timeout=this.timeOutInSeconds * 100)
+ var url = this.cur.protocol & "://" & this.host & ":" & this.port.intToStr
+ if client.get(url).status != "200 OK":
+ return false
+ return true
+
 proc close*(this: Connection) =
  # There is no Actual close so just cleaning the connection information. 
  this.cur = Cursor()
@@ -52,11 +64,14 @@ proc close*(this: Connection) =
  discard
 
 proc commit*(this: Connection) =
- discard
+ raise newException(NoTransactionError, "Presto does not have transcations.")
 
 proc cursor*(this: Connection): Cursor =
  return this.cur
 
+proc rollback*(this: Connection) =
+ raise newException(NoTransactionError, "Presto does not have transcations.")
+
 proc getColumns*(this: Cursor): seq[string] =
  return this.resultSet.columns
 
@@ -65,7 +80,7 @@ proc processResponse(this: Cursor, response: Response) =
  raise newException(NoConnectionError, "Status code returned bad. %s" % response.status)
  let data = parseJson(response.body)
  if data.hasKey("error"):
- raise newException(CursorError, data["error"].getStr)
+ raise newException(QueryExecutionError, data["error"]["message"].getStr)
  var state = data["stats"]["state"].str
  if not data.hasKey("nextUri"):
  this.resultSet.nextUri = ""
@@ -96,41 +111,36 @@ proc processResponse(this: Cursor, response: Response) =
  this.resultSet.state = state
  return
 
-proc rollback*(this: Connection) =
- raise newException(NoTransactionError, "Presto does not have transcations")
-
 proc execute*(this: Cursor, query: string) =
- this.resultSet = ResultSet(nextUri: "", state: "STARTED", columns: @[])
  var additional: seq[string] = @[]
  if this.sessionProps.len != 0:
  var additionalProperties = this.sessionProps.split(",")
  var k = range(additionalProperties.len)
  var evens = filter(zip(k, additionalProperties), proc (x: (int, string)): bool = x[0] mod 2 == 0)
  var odds = filter(zip(k, additionalProperties), proc (x: (int, string)): bool = x[0] mod 2 != 0)
  for ind in countup(0, evens.len - 1):
- additional.add(format("$1=$2", evens[ind][1], odds[ind][1])) 
+ additional.add(format("$1=$2", evens[ind][1], odds[ind][1]))
  var client = newHttpClient()
- var protocol = "http://"
- var url = protocol & this.host & format(":$1", this.port) & "/v1/statement/"
+ var url = this.protocol & "://" & this.host & format(":$1", this.port) & "/v1/statement/"
  client.headers = newHttpHeaders()
  client.headers.add("X-Presto-Catalog", this.catalog)
  client.headers.add("X-Presto-Schema", this.schema)
  client.headers.add("X-Presto-Source", this.source)
  client.headers.add("X-Presto-User", this.username)
  if additional.len > 0:
  client.headers.add("X-Presto-Session", additional.join(","))
- this.resultSet.nextUri = url
- this.resultSet.client = client
+ this.resultSet = ResultSet(nextUri: url, state: "STARTED", columns: @[], client: client)
  var response = client.request(this.resultSet.nextUri, httpMethod = HttpPost, body = query)
  this.processResponse(response)
 
 proc fetchOne*(this: Cursor): seq[string] =
  if this.resultSet.state == "FINISHED":
  raise newException(CursorError, "No More Rows.")
+
  if this.resultSet.data.len > 0:
  return this.resultSet.data.pop()
  elif this.resultSet.data.len == 0:
- os.sleep(500) # Sleeps 500 miliseconds before each request.
+ os.sleep(this.poolInterval)
  var response = this.resultSet.client.request(this.resultSet.nextUri, httpMethod = HttpGet)
  this.processResponse(response)
 
@@ -150,34 +160,43 @@ proc fetchAll*(this: Cursor): seq[seq[string]] =
  break
  if this.resultSet.data.len > 0:
  queryData.add(this.resultSet.data)
- # Sleeps 500 miliseconds before each request.
- os.sleep(100)
+ os.sleep(this.poolInterval)
  var response = this.resultSet.client.request(this.resultSet.nextUri, httpMethod = HttpGet)
  this.processResponse(response)
  return queryData
 
-proc connect*(host: string, port: int, catalog: string, schema: string,
- username: string, source = "NimPresto", sessionProps = ""): Connection =
+proc open*(host: string, port: int, protocol: string = "http", catalog: string, schema: string,
+ username: string, source = "NimPresto", poolInterval = 1,
+ sessionProps = "", tableCursor = false): Connection =
+ if protocol notin ["http", "https"]:
+ raise newException(NotValidProtocolError, "The protocol you specified is not valid protocol: %s" % protocol)
  let cursor = Cursor(catalog: catalog,
  schema: schema,
  source: source, 
  sessionProps: sessionProps,
- poolInterval: "1", 
+ poolInterval: poolInterval * 1000,
+ tableCursor: tableCursor,
  username: username,
  host: host,
+ protocol: protocol,
  port: port.intToStr)
- return Connection(
+ let connection = Connection(
  host: host,
  port: port,
+ timeOutInSeconds: 10,
  cur: cursor
  )
+ if not connection.ping():
+ raise newException(NoConnectionError, "Failed to Established Connection.")
+ return connection
 
 
 when isMainModule:
- let con = connect("HOST", 8889, "hive", "dwh", "benny")
+ let con = open(host="host", port=8889, catalog="hive", schema="dwh", username="benny")
  defer: con.close()
  var cur = con.cursor()
- cur.execute("SQL")
+ cur.execute("SELECT * FROM abc")
+ echo(cur.fetchOne())
  #echo(cur.getColumns())
  # for s in cur.fetchMany(10):
  # echo(s)

presto.nimble → db_presto.nimble

@@ -1,6 +1,6 @@
 # Package
 
-version = "0.5.0"
+version = "0.7.0"
 author = "Bennyelg"
 description = "prestodb simple connector"
 license = "MIT"