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Xojo Plugin

BatchModify - Add a Label to each Message in Search Results

See more GMail REST API Examples

Searchs GMail for messages meeting a criteria and adds a label to each message found.

Chilkat Xojo Plugin Downloads

Xojo Plugin
Dim success As Boolean
success = False

// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

Dim http As New Chilkat.Http
http.AuthToken = "GMAIL-ACCESS-TOKEN"

Dim userId As String
userId = "me"
success = http.SetUrlVar("userId",userId)

Dim query As String
query = "subject:questions"
success = http.SetUrlVar("query",query)

Dim url As String
url = "https://www.googleapis.com/gmail/v1/users/{$userId}/messages?q={$query}"

Dim sb As New Chilkat.StringBuilder
success = http.QuickGetSb(url,sb)
If (success = False) Then
    System.DebugLog(http.LastErrorText)
    Return
End If

Dim json As New Chilkat.JsonObject
success = json.LoadSb(sb)
json.EmitCompact = False
System.DebugLog(json.Emit())

If (http.LastStatus <> 200) Then
    System.DebugLog("Failed.")
    Return
End If

// If successful, the received JSON looks like this:
// {
//   "messages": [
//     {
//       "id": "166f583051d36144",
//       "threadId": "166f583051d36144"
//     },
//     {
//       "id": "166f5815e1f36144",
//       "threadId": "166f5815e1f36144"
//     },
// 	...
//     {
//       "id": "166f580639e36144",
//       "threadId": "166f580639e36144"
//     },
//     {
//       "id": "15dbc2e28ec789c6",
//       "threadId": "15dbc2e28ec789c6"
//     }
//   ],
//   "nextPageToken": "13434766102274844688",
//   "resultSizeEstimate": 103
// }
// 

// Next, we'll be sending an HTTP POST to add the label "questions" to each message in the
// search results.  The JSON to be sent for the batchModify is this:

// 	{
// 	  "ids": [
// 	    string
// 	  ],
// 	  "addLabelIds": [
// 	    string
// 	  ],
// 	  "removeLabelIds": [
// 	    string
// 	  ]
// 	}

// We'll omit "removeLabelIds" because we're not removing any labels.
// We are parsing the JSON search results, and at the same time building the batchModify JSON.

Dim json2 As New Chilkat.JsonObject

Dim i As Int32
i = 0
Dim numMessages As Int32
numMessages = json.SizeOfArray("messages")
While (i < numMessages)
    json.I = i
    Dim id As String
    id = json.StringOf("messages[i].id")
    json2.I = i
    success = json2.UpdateString("ids[i]",id)
    i = i + 1
Wend

// We need the id of the label (not the name).
// I know the name of the label is "questions", but I need to know the id.
// See this example: Get Label Id by Name
// The id of my label named "questions" is "Label_43"
Dim labelId As String
labelId = "Label_43"
success = json2.UpdateString("addLabelIds[0]",labelId)
success = json2.UpdateNewArray("removeLabelIds")

json2.EmitCompact = False
System.DebugLog(json2.Emit())

// Send the batchModify
url = "https://www.googleapis.com/gmail/v1/users/{$userId}/messages/batchModify"
Dim resp As New Chilkat.HttpResponse
success = http.HttpJson("POST",url,json2,"application/json",resp)
If (success = False) Then
    System.DebugLog(http.LastErrorText)
    Return
End If

System.DebugLog("status = " + Str(resp.StatusCode))

// A 204 response status indicate success.
If (resp.StatusCode <> 204) Then
    System.DebugLog(resp.BodyStr)
    System.DebugLog("Failed.")
    Return
End If

// The 204 response has an empty response body..

System.DebugLog("BatchModify success!")