(Swift 3,4,5...) BatchModify - Add a Label to each Message in Search Results

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

Chilkat Downloads for the Swift Programming Language MAC OS X (Cocoa) Objective-C/Swift Libs iOS Objective-C/Swift Libs

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

    var success: Bool

    let http = CkoHttp()!
    http.authToken = "GMAIL-ACCESS-TOKEN"

    var userId: String? = "me"
    http.setUrlVar("userId", value: userId)

    var query: String? = "subject:questions"
    http.setUrlVar("query", value: query)

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

    let sb = CkoStringBuilder()!
    success = http.quickGetSb(url, sbContent: sb)
    if success != true {
        print("\(http.lastErrorText!)")
        return
    }

    let json = CkoJsonObject()!
    json.loadSb(sb)
    json.emitCompact = false
    print("\(json.emit()!)")

    if http.lastStatus.intValue != 200 {
        print("Failed.")
        return
    }

    // 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.

    let json2 = CkoJsonObject()!

    var i: Int = 0
    var numMessages: Int = json.size(ofArray: "messages").intValue
    while (i < numMessages) {
        json.i = i
        var id: String? = json.string(of: "messages[i].id")
        json2.i = i
        json2.update("ids[i]", value: id)
        i = i + 1
    }

    // 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"
    var labelId: String? = "Label_43"
    json2.update("addLabelIds[0]", value: labelId)
    json2.updateNewArray("removeLabelIds")

    json2.emitCompact = false
    print("\(json2.emit()!)")

    // Send the batchModify
    url = "https://www.googleapis.com/gmail/v1/users/{$userId}/messages/batchModify"
    var resp: CkoHttpResponse? = http.postJson3(url, contentType: "application/json", json: json2)
    if http.lastMethodSuccess != true {
        print("\(http.lastErrorText!)")
        return
    }

    print("status = \(resp!.statusCode.intValue)")

    // A 204 response status indicate success.
    if resp!.statusCode.intValue != 204 {
        print("\(resp!.bodyStr!)")
        print("Failed.")
        resp = nil
        return
    }

    // The 204 response has an empty response body..
    resp = nil

    print("BatchModify success!")

}