Objective-C Requires Chilkat v11.7.0+

Box: Resolve a File Version by Name and Verify the Download

See more Box Examples

Run the reusable setup once per HttpCurl object, then select names and execute the operation. The setup is repeated here only to make this published example independently runnable. One target request requires file_id and file_version_id. The engine uses AddOutput2 for name lookups and AddOutput for version/SHA-1 metadata, then downloads that version to local_path and verifies its digest.

See the Box API guide for setup and the complete workflow.

Objective-C

#import <CkoHttpCurl.h>
#import <CkoStringBuilder.h>
#import <NSString.h>
#import <CkoCrypt2.h>

BOOL success = NO;

//  Requires Chilkat 11.7.0 or later and a previously unlocked Chilkat bundle.
//  See Global Unlock Sample.
//  Guide: Box API Guide.

success = NO;

//  BEGIN ONE-TIME SETUP
//  This block is repeated so each published example can run on its own.
//  In an application, run the setup example once and pass the SAME curl object
//  to operation code below. Do not recreate it for every operation.
//  See Reusable Box HttpCurl Setup.
CkoHttpCurl *curl = [[CkoHttpCurl alloc] init];
[curl SetVar: @"access_token" varValue: @"BOX_ACCESS_TOKEN"];
[curl SetVar: @"parent_name" varValue: @"/"];
//  Box's fixed root ID is an implementation detail; callers supply names.
[curl SetVar: @"parent_id" varValue: @"0"];
CkoStringBuilder *setupCommand = [[CkoStringBuilder alloc] init];
int setupReplacements;

//  Register findParent; registration sends no request.
[setupCommand SetString: @"curl -X GET \"https://api.box.com/2.0/folders/0/items?limit=1000&fields=id,type,name\" -H \"Authorization: Bearer ACCESS_TOKEN\""];
setupReplacements = [[setupCommand Replace: @"ACCESS_TOKEN" replacement: [curl GetVar: @"access_token"]] intValue];
success = [curl AddFunction: @"findParent" curl: [setupCommand GetAsString]];
if (success != YES) {
    NSLog(@"%@",curl.LastErrorText);
    return;
}

//  Register findFolder; registration sends no request.
[setupCommand SetString: @"curl -X GET \"https://api.box.com/2.0/folders/{{parent_id}}/items?limit=1000&fields=id,type,name\" -H \"Authorization: Bearer ACCESS_TOKEN\""];
setupReplacements = [[setupCommand Replace: @"ACCESS_TOKEN" replacement: [curl GetVar: @"access_token"]] intValue];
success = [curl AddFunction: @"findFolder" curl: [setupCommand GetAsString]];
if (success != YES) {
    NSLog(@"%@",curl.LastErrorText);
    return;
}

//  Register findFile; registration sends no request.
[setupCommand SetString: @"curl -X GET \"https://api.box.com/2.0/folders/{{folder_id}}/items?limit=1000&fields=id,type,name\" -H \"Authorization: Bearer ACCESS_TOKEN\""];
setupReplacements = [[setupCommand Replace: @"ACCESS_TOKEN" replacement: [curl GetVar: @"access_token"]] intValue];
success = [curl AddFunction: @"findFile" curl: [setupCommand GetAsString]];
if (success != YES) {
    NSLog(@"%@",curl.LastErrorText);
    return;
}

//  Register findDestination; registration sends no request.
[setupCommand SetString: @"curl -X GET \"https://api.box.com/2.0/folders/0/items?limit=1000&fields=id,type,name\" -H \"Authorization: Bearer ACCESS_TOKEN\""];
setupReplacements = [[setupCommand Replace: @"ACCESS_TOKEN" replacement: [curl GetVar: @"access_token"]] intValue];
success = [curl AddFunction: @"findDestination" curl: [setupCommand GetAsString]];
if (success != YES) {
    NSLog(@"%@",curl.LastErrorText);
    return;
}

//  Register getFileDetails; registration sends no request.
[setupCommand SetString: @"curl -X GET \"https://api.box.com/2.0/files/{{file_id}}?fields=id,sha1,file_version\" -H \"Authorization: Bearer ACCESS_TOKEN\""];
setupReplacements = [[setupCommand Replace: @"ACCESS_TOKEN" replacement: [curl GetVar: @"access_token"]] intValue];
success = [curl AddFunction: @"getFileDetails" curl: [setupCommand GetAsString]];
if (success != YES) {
    NSLog(@"%@",curl.LastErrorText);
    return;
}

//  Register getEnterprise; registration sends no request.
[setupCommand SetString: @"curl -X GET \"https://api.box.com/2.0/users/me?fields=enterprise\" -H \"Authorization: Bearer ACCESS_TOKEN\""];
setupReplacements = [[setupCommand Replace: @"ACCESS_TOKEN" replacement: [curl GetVar: @"access_token"]] intValue];
success = [curl AddFunction: @"getEnterprise" curl: [setupCommand GetAsString]];
if (success != YES) {
    NSLog(@"%@",curl.LastErrorText);
    return;
}

//  Register output rules once. Chilkat 11.7.0 evaluates {{name}} variables
//  when extracting each output, using the current value at that time.
success = [curl AddOutput2: @"findParent" arrayPath: @"entries" wherePath: @"name" whereValue: @"{{parent_name}}" caseSensitive: YES subPath: @"id" varName: @"parent_id"];
if (success != YES) {
    NSLog(@"%@",curl.LastErrorText);
    return;
}

success = [curl AddOutput2: @"findFolder" arrayPath: @"entries" wherePath: @"name" whereValue: @"{{folder_name}}" caseSensitive: YES subPath: @"id" varName: @"folder_id"];
if (success != YES) {
    NSLog(@"%@",curl.LastErrorText);
    return;
}

success = [curl AddOutput2: @"findFile" arrayPath: @"entries" wherePath: @"name" whereValue: @"{{file_name}}" caseSensitive: YES subPath: @"id" varName: @"file_id"];
if (success != YES) {
    NSLog(@"%@",curl.LastErrorText);
    return;
}

success = [curl AddOutput2: @"findDestination" arrayPath: @"entries" wherePath: @"name" whereValue: @"{{destination_name}}" caseSensitive: YES subPath: @"id" varName: @"destination_id"];
if (success != YES) {
    NSLog(@"%@",curl.LastErrorText);
    return;
}

success = [curl AddOutput: @"getFileDetails" jsonPath: @"file_version.id" varName: @"file_version_id"];
if (success != YES) {
    NSLog(@"%@",curl.LastErrorText);
    return;
}

success = [curl AddOutput: @"getFileDetails" jsonPath: @"sha1" varName: @"file_sha1"];
if (success != YES) {
    NSLog(@"%@",curl.LastErrorText);
    return;
}

success = [curl AddOutput: @"getEnterprise" jsonPath: @"enterprise.id" varName: @"enterprise_id"];
if (success != YES) {
    NSLog(@"%@",curl.LastErrorText);
    return;
}

//  END ONE-TIME SETUP
//  The name lookups below assume each listing fits in one page (1000 items).
//  Parent and destination names select root children; folder_name selects a child
//  of parent_name. "/" selects the root parent. These are not arbitrary paths.

//  BEGIN OPERATION -- keep the configured object when reusing it.
//  Inputs are names. Retain cached IDs when the selected names have not changed.
NSString *parentName = @"/";
NSString *folderName = @"images";
NSString *fileName = @"penguins.jpg";
if (([curl GetVar: @"parent_name"] != parentName) || ((parentName == @"/") && ([curl VarDefined: @"parent_id"] == NO))) {
    [curl SetVar: @"parent_name" varValue: parentName];
    [curl ClearVar: @"parent_id"];
    [curl ClearVar: @"folder_id"];
    [curl ClearVar: @"file_id"];
    [curl ClearVar: @"file_version_id"];
    [curl ClearVar: @"file_sha1"];
    if (parentName == @"/") {
        [curl SetVar: @"parent_id" varValue: @"0"];
    }

}

if ([curl GetVar: @"folder_name"] != folderName) {
    [curl SetVar: @"folder_name" varValue: folderName];
    [curl ClearVar: @"folder_id"];
    [curl ClearVar: @"file_id"];
    [curl ClearVar: @"file_version_id"];
    [curl ClearVar: @"file_sha1"];
}

if ([curl GetVar: @"file_name"] != fileName) {
    [curl SetVar: @"file_name" varValue: fileName];
    [curl ClearVar: @"file_id"];
    [curl ClearVar: @"file_version_id"];
    [curl ClearVar: @"file_sha1"];
}

[curl SetVar: @"local_path" varValue: @"qa_output/penguins-verified.jpg"];
//  file_version_id is also unknown, so getFileDetails becomes a prerequisite.
//  Its AddOutput mappings cache both the selected version and its SHA-1.
[curl ClearTargetOutput: @"*"];
CkoStringBuilder *authorizedCommand1 = [[CkoStringBuilder alloc] init];
[authorizedCommand1 SetString: @"curl -X GET \"https://api.box.com/2.0/files/{{file_id}}/content?version={{file_version_id}}\" -H \"Authorization: Bearer {{access_token}}\" -L -o \"{{local_path}}\""];
int headerReplacement1 = [[authorizedCommand1 Replace: @"{{access_token}}" replacement: [curl GetVar: @"access_token"]] intValue];
success = [curl DoYourThing: [authorizedCommand1 GetAsString]];
if ((success != YES) || ([curl.StatusCode intValue] != 200)) {
    NSLog(@"%@%d",@"Box request failed. HTTP status: ",[curl.StatusCode intValue]);
    NSLog(@"%@%d",@"Failure reason: ",[curl.FailReason intValue]);
    NSLog(@"%@",curl.ResponseBodyStr);
    return;
}

CkoCrypt2 *digest = [[CkoCrypt2 alloc] init];
digest.HashAlgorithm = @"sha1";
digest.EncodingMode = @"hex_lower";
NSString *actualSha1 = [digest HashFileENC: [curl GetVar: @"local_path"]];
if (digest.LastMethodSuccess != YES) {
    NSLog(@"%@",digest.LastErrorText);
    return;
}

if (actualSha1 != [curl GetVar: @"file_sha1"]) {
    NSLog(@"%@",@"Downloaded content did not match the selected version's SHA-1.");
    return;
}

NSLog(@"%@",@"Version-specific download verified.");