来自 VB.NET 的 Neo4j 2.3.0-M01 密码查询失败
Neo4j 2.3.0-M01 cypher query from VB.NET failing
最近在 Windows 7 Prof PC 上安装了新版本的 Neo4j。能够使用 API 批量插入创建节点。来自 Web 界面的 Cypher 查询可以正常工作,但现在在注释“检索查询结果,将在 JSon 中的行的 VB.NET 代码中失败。这个运行在之前的Neo4j版本上没问题(2.2.x)
Public Shared Function DBQuery(URI As String, PostString As String) As DataView
'runs query and returns JSon results as a dataview
'Uses POST method to access Neo4j Server API
Dim S As String = ""
Dim HttpWReq As System.Net.HttpWebRequest = System.Net.HttpWebRequest.Create(URI)
HttpWReq.Method = "POST"
HttpWReq.ContentType = "application/json"
HttpWReq.Accept = "application/json"
Dim B1() As Byte = System.Text.Encoding.Unicode.GetBytes(PostString, 0, Len(PostString))
'POST query
'http://blog.micic.ch/net/using-neo4j-graph-db-with-c-net
HttpWReq.Connection = "Open"
HttpWReq.ContentLength = B1.Length
Dim newStream As IO.Stream = HttpWReq.GetRequestStream()
'this method closes stream before calling getResponse
Using newStream
newStream.Write(B1, 0, B1.Length)
End Using
'retrieve results of query, which will be in JSon
Dim HttpWResp As System.Net.HttpWebResponse = CType(HttpWReq.GetResponse(), System.Net.HttpWebResponse)
HttpWReq.KeepAlive = False
HttpWReq.Timeout = 15000000
Dim E As System.Text.Encoding = System.Text.Encoding.GetEncoding(HttpWResp.CharacterSet)
Dim SR As IO.StreamReader = New IO.StreamReader(HttpWResp.GetResponseStream, encoding:=E)
S = SR.ReadToEnd 'JSon result
Return JSonToDV(S)
End Function
v2.3.0 的文档表明需要不同的 conf 文件设置,但这不起作用。文档位于 http://neo4j.com/docs/2.3.0-M01/server-configuration.html 。 neo4j-server.properties 文件最初没有 org.neo4j.server.database.location=data/graph.db 的条目。添加建议的行 (org.neo4j.server.database.location="C:/Data/Neo4j/UMLS/graph.db") 然后数据库无法启动。将不胜感激建议的解决方案。
问题不在于 Neo4j 2.3.0,而在于 VB.NET 代码。更正后的有效代码是:
Public Shared Function DBQuery(URI As String, PostString As String, method As EnumLib.WebServiceMethod) As DataView
'Used for individual API calls; see BulkUpload for other method
'Uses POST method to access Neo4j Server API
Dim ID As Long = 0
Dim HttpWReq As System.Net.HttpWebRequest = System.Net.HttpWebRequest.Create(URI)
Select Case method
Case EnumLib.WebServiceMethod.POST
HttpWReq.Method = "POST"
Case EnumLib.WebServiceMethod.GET
HttpWReq.Method = "GET"
End Select
HttpWReq.ContentType = "application/json"
HttpWReq.Accept = "application/json"
Dim B1() As Byte = System.Text.Encoding.UTF8.GetBytes(PostString, 0, Len(PostString))
'http://blog.micic.ch/net/using-neo4j-graph-db-with-c-net
HttpWReq.Connection = "Open"
Dim S As String = ""
Try
HttpWReq.ContentLength = B1.Length
Dim newStream As IO.Stream = HttpWReq.GetRequestStream()
'this method closes stream before calling getResponse
Using newStream
newStream.Write(B1, 0, B1.Length)
End Using
Dim HttpWResp As System.Net.HttpWebResponse = CType(HttpWReq.GetResponse(), System.Net.HttpWebResponse)
Dim E As System.Text.Encoding = System.Text.Encoding.GetEncoding(HttpWResp.CharacterSet)
Dim SR As IO.StreamReader = New IO.StreamReader(HttpWResp.GetResponseStream, encoding:=E)
S = SR.ReadToEnd
Catch ex As System.Net.WebException
MsgBox("Message: " & vbLf & ex.Message)
Dim RS As IO.StreamReader = New IO.StreamReader(ex.Response.GetResponseStream)
Dim SS As String = RS.ReadToEnd
PostReturnString = "WebException Error: " & ex.Message & vbLf & vbLf & ex.Status & vbLf & vbLf & SS
' MsgBox("Status: " & vbLf & ex.Status & vbLf & vbLf & SS)
End Try
Return JSonToDV(S)
End Function
最近在 Windows 7 Prof PC 上安装了新版本的 Neo4j。能够使用 API 批量插入创建节点。来自 Web 界面的 Cypher 查询可以正常工作,但现在在注释“检索查询结果,将在 JSon 中的行的 VB.NET 代码中失败。这个运行在之前的Neo4j版本上没问题(2.2.x)
Public Shared Function DBQuery(URI As String, PostString As String) As DataView
'runs query and returns JSon results as a dataview
'Uses POST method to access Neo4j Server API
Dim S As String = ""
Dim HttpWReq As System.Net.HttpWebRequest = System.Net.HttpWebRequest.Create(URI)
HttpWReq.Method = "POST"
HttpWReq.ContentType = "application/json"
HttpWReq.Accept = "application/json"
Dim B1() As Byte = System.Text.Encoding.Unicode.GetBytes(PostString, 0, Len(PostString))
'POST query
'http://blog.micic.ch/net/using-neo4j-graph-db-with-c-net
HttpWReq.Connection = "Open"
HttpWReq.ContentLength = B1.Length
Dim newStream As IO.Stream = HttpWReq.GetRequestStream()
'this method closes stream before calling getResponse
Using newStream
newStream.Write(B1, 0, B1.Length)
End Using
'retrieve results of query, which will be in JSon
Dim HttpWResp As System.Net.HttpWebResponse = CType(HttpWReq.GetResponse(), System.Net.HttpWebResponse)
HttpWReq.KeepAlive = False
HttpWReq.Timeout = 15000000
Dim E As System.Text.Encoding = System.Text.Encoding.GetEncoding(HttpWResp.CharacterSet)
Dim SR As IO.StreamReader = New IO.StreamReader(HttpWResp.GetResponseStream, encoding:=E)
S = SR.ReadToEnd 'JSon result
Return JSonToDV(S)
End Function
v2.3.0 的文档表明需要不同的 conf 文件设置,但这不起作用。文档位于 http://neo4j.com/docs/2.3.0-M01/server-configuration.html 。 neo4j-server.properties 文件最初没有 org.neo4j.server.database.location=data/graph.db 的条目。添加建议的行 (org.neo4j.server.database.location="C:/Data/Neo4j/UMLS/graph.db") 然后数据库无法启动。将不胜感激建议的解决方案。
问题不在于 Neo4j 2.3.0,而在于 VB.NET 代码。更正后的有效代码是:
Public Shared Function DBQuery(URI As String, PostString As String, method As EnumLib.WebServiceMethod) As DataView
'Used for individual API calls; see BulkUpload for other method
'Uses POST method to access Neo4j Server API
Dim ID As Long = 0
Dim HttpWReq As System.Net.HttpWebRequest = System.Net.HttpWebRequest.Create(URI)
Select Case method
Case EnumLib.WebServiceMethod.POST
HttpWReq.Method = "POST"
Case EnumLib.WebServiceMethod.GET
HttpWReq.Method = "GET"
End Select
HttpWReq.ContentType = "application/json"
HttpWReq.Accept = "application/json"
Dim B1() As Byte = System.Text.Encoding.UTF8.GetBytes(PostString, 0, Len(PostString))
'http://blog.micic.ch/net/using-neo4j-graph-db-with-c-net
HttpWReq.Connection = "Open"
Dim S As String = ""
Try
HttpWReq.ContentLength = B1.Length
Dim newStream As IO.Stream = HttpWReq.GetRequestStream()
'this method closes stream before calling getResponse
Using newStream
newStream.Write(B1, 0, B1.Length)
End Using
Dim HttpWResp As System.Net.HttpWebResponse = CType(HttpWReq.GetResponse(), System.Net.HttpWebResponse)
Dim E As System.Text.Encoding = System.Text.Encoding.GetEncoding(HttpWResp.CharacterSet)
Dim SR As IO.StreamReader = New IO.StreamReader(HttpWResp.GetResponseStream, encoding:=E)
S = SR.ReadToEnd
Catch ex As System.Net.WebException
MsgBox("Message: " & vbLf & ex.Message)
Dim RS As IO.StreamReader = New IO.StreamReader(ex.Response.GetResponseStream)
Dim SS As String = RS.ReadToEnd
PostReturnString = "WebException Error: " & ex.Message & vbLf & vbLf & ex.Status & vbLf & vbLf & SS
' MsgBox("Status: " & vbLf & ex.Status & vbLf & vbLf & SS)
End Try
Return JSonToDV(S)
End Function