我在这里尝试了很多组合，但除非我添加content网址参数并将contentType参数设置为text/plain，否则它会一直失败。这很酷，几乎没用。我需要打印PNG文件，这些文件不适合URL。
我正在使用gtm-http-fetcher，因此很容易处理身份验证。这是我的打印实现：
@implementation EBCloudPrint
+(void) printFile:(NSString *)file{
[EBCloudPrint printImage:[NSData dataWithContentsOfFile:file]];
}
+(void) printImage:(NSData *)image{
NSString *printer = [EBPreferences getUserPreference:PREFERENCE_GOOGLE_CLOUD_PRINTER];
if (printer == nil) {
NSLog(@"Ignoring print: no printer selected");
return;
}
GTMOAuth2Authentication *auth = [GTMOAuth2ViewControllerTouch authForGoogleFromKeychainForName:GOOGLE_KEYCHAIN_NAME
clientID:GOOGLE_CLIENT_ID
clientSecret:GOOGLE_CLIENT_SECRET];
// Return immediately if we haven't auth
if (![auth canAuthorize]) {
return;
}
[GTMHTTPFetcher setLoggingEnabled:YES];
GTMMIMEDocument *doc = [GTMMIMEDocument MIMEDocument];
[doc addPartWithHeaders:@{@"Content-Disposition": @"form-data; name=\"ticket\""}
body:[@"{\"version\": \"1.0\", \"print\": {}}" dataUsingEncoding:NSUTF8StringEncoding]];
[doc addPartWithHeaders:@{@"Content-Disposition": @"form-data; name=\"content\"; filename=\"eb.png\"", @"Content-Type": @"image/png"}
body:image];
NSInputStream *stream = nil;
[doc generateInputStream:&stream
length:NULL
boundary:NULL];
if (stream) {
NSString *url = [NSString stringWithFormat:@"%@?output=json&printerid=%@&contentType=image/png&title=eb&tag=eb_ios", CLOUD_PRINT_JOB_URL, printer];
NSLog(@"Printing to: %@", url);
GTMHTTPFetcher *fetcher = [GTMHTTPFetcher fetcherWithURLString:url];
[fetcher setPostStream:stream];
[fetcher setAuthorizer:auth];
[fetcher beginFetchWithCompletionHandler:^(NSData *data, NSError *error) {
if (data) {
NSLog(@"data: %@", [NSString stringWithUTF8String:[data bytes]]);
}
if (error) {
NSLog(@"---- error: %@", error.localizedDescription);
}
}];
stream = nil;
fetcher = nil;
}
}
+(NSArray *) getPrinters{
return [[NSArray alloc] init];
}
@end
以下是服务器的响应：
{
"success": false,
"message": "Document missing.",
"request": {
"time": "0",
"users": [
"..."
],
"params": {
"": [
"\\r/@R\\r`\\u0015\\u003c`_\\u001d\\u0018\\u0016Z\\u0002\\u00072d\\fEr\\rG \\u000bk7\\u001c\\u003d'k^4j?\\u001a\\u0014' yd#A\\u0016\\u0000*\\\"q\\u0004\\u0015H\\u00035\\u001fYLWN@1p"
],
"title": [
"eb"
],
"\\r\\n--END_OF_PART\\r\\nContent-Disposition: form-data; name": [
"\\\"ticket\\\"\\r\\n\\r\\n{\\\"version\\\": \\\"1.0\\\", \\\"print\\\": {}}\\r\\n--END_OF_PART\\r\\nContent-Disposition: form-data; name\\u003d\\\"content\\\"; filename\\u003d\\\"eb.png\\\"\\r\\nContent-Type: image/png\\r\\n\\r\\nPNG\\r\\n\\u001a\\n\\u0000\\u0000\\u0000\\rIHDR\\u0000\\u0000\\u0000\\u0019\\u0000\\u0000\\u0000\\u0019\\b\\u0006\\u0000\\u0000\\u0000c\\u0000\\u0000\\u0000\\u001ciDOT\\u0000\\u0000\\u0000\\u0002\\u0000\\u0000\\u0000\\u0000\\u0000\\u0000\\u0000\\r\\u0000\\u0000\\u0000(\\u0000\\u0000\\u0000\\r\\u0000\\u0000\\u0000\\f\\u0000\\u0000\\u0002\\u0010~\\u0000\\u0000\\u0002KIDATH\\rb`\\u0003V\\u001d;Y5uoBj9ek.'-zo\\u0014\\u0013\\u0006A y:\\u003cj5w3yg8~`\\u001a\\u0007A@q"
],
"e": [
"ggW\\r0n\\u0001`1B\\u003cH\\u001dH\\u003dH\\u001fH?}oX%..\\u000bt!0Xp\\u001a2z\\u003e~9"
],
"tag": [
"eb_ios"
],
"printerid": [
"45..."
],
"contentType": [
"image/png"
],
"Cy\\u0007_S5]KoE\\u0018\\u0006\\u0019l\\n bQ\\u003cC@@A": [
"wmI\\u001f\\u0016\\u0000#\\u001b\\u001c$js[.\\u0001[f\\u0010;\\u001f @C}rI\\bE\\u000f\\n\\u000f\\u0012\\u0017W\\u000bh\\tsvxL[y%a\\u003ez@\\t\\u0004d\\u001e\\\\Ep]Y9d\\u0016`uf\\u0003\\u003e)a`4(A\\u0003\\u000b2w\\u0018P\\u0000/L\\u00112\\r\\u0007k\\u001a,w_n\\u0003-\\u000fd\\u001eGc\\u0018J'Z"
],
"output": [
"json"
],
",;mJl\\u0016,\\u0005\\u00032\\u000fd.a`": [
"wmI\\t@\\u001a-S\\u0016b5H?\\u001cy(\\u00168\\u0007_S5]K\\u000f\\\"S,0[\\u0012\\u0005 s@aX\\u0002\\u0012w50 l\\u0004\\u0001b\\u003e~9X-\\tn?tY%gYPP\\u0005!\\u000eW,\\u0003\\u0019\\u000e\\u0007\\u0003\\u0007\\u0003En5w3\\u003d`\\u0003P\\u000b@\\u00022\\u0018D q\\u003cH\\u001dH\\u003dAC)Xu\\u0018g\\t-[\\u0004\\f*\\tD q\\u003cH\\u001d601\\u0000tI\\u0016:^\\u0000\\u0000\\u0000\\u0000IENDB`\\r\\n--END_OF_PART--\\r\\n"
],
"NK@'-~\\u0000_A^Cv\\u00012\\u001b\\u0014\\u003eEnYP\\u003ei70?4\\u0000s3Xq\\t2\\u0003d.|\\u0000\\u0000\\u0000\\u0000x\\u0001l$\\u0000\\u0000\\u0001IDATc0OZ8~X1P\\\\Y?3@A\\u0003\\u003c,q\\u0011V} @'-~[v\\\\\\nA^,is`tz@@\\u0016P:a2IiM\\u0013\\\\K@\\u0005hrFx\\f\\u0013O\\u0012}\\u00022\\u000fd.|s\\u001c2\\u000bo4#/^}\\u0012\\u0016\\\\v\\\\\\t%6\\f\\u0005\\u003c \\u0017\\u001e.\\u000e(#\\u0001dY}": [
""
]
},
"user": "...."
},
"errorCode": 412
}
有些不对劲。我无法确定它。如果有人在这里有任何见解或使用GTM打印图像的例子[El Goog是适用于iOS的超薄游戏]，我非常感谢！
答案 0 :(得分：0)
我在Google Cloud Print邮件列表的帮助下找出了问题。希望我能抽出时间将其打包成Pod并使其更易于使用。
免责声明：此处有一些未完成/未清理的部分，但重点关注Mime文档，故障单和NSInputStream。
@implementation EBCloudPrint
+(void) printFile:(NSString *)file completion:(void (^)(void))completion{
[EBCloudPrint printImage:[NSData dataWithContentsOfFile:file] completion:completion];
}
+(void) printImage:(NSData *)image completion:(void (^)(void))completion{
NSString *printer = [EBPreferences getUserPreference:PREFERENCE_GOOGLE_CLOUD_PRINTER];
if (printer == nil) {
NSLog(@"Ignoring print");
if (completion) {
completion();
}
return;
}
GTMOAuth2Authentication *auth = [GTMOAuth2ViewControllerTouch authForGoogleFromKeychainForName:GOOGLE_KEYCHAIN_NAME
clientID:GOOGLE_CLIENT_ID
clientSecret:GOOGLE_CLIENT_SECRET];
// Return immediately if we haven't auth
if (![auth canAuthorize]) {
if (completion) {
completion();
}
return;
}
[GTMHTTPFetcher setLoggingEnabled:YES];
GTMMIMEDocument *doc = [GTMMIMEDocument MIMEDocument];
// MediaSize docs: https://developers.google.com/cloud-print/docs/cdd#MediaSize
NSString *ticketJson = @"{\"version\": \"1.0\", \"print\": { \"media_size\": { \"width_microns\": 101600, \"height_microns\": 152400 }}}"; //media_size: 4x6
[doc addPartWithHeaders:@{@"Content-Disposition": @"form-data; name=\"ticket\"", @"Content-Type": @"text/json"}
body:[ticketJson dataUsingEncoding:NSUTF8StringEncoding]];
[doc addPartWithHeaders:@{@"Content-Disposition": @"form-data; name=\"content\"; filename=\"eb.png\"", @"Content-Type": @"image/png"}
body:image];
NSString *boundary = nil;
unsigned long long length = -1;
NSInputStream *stream = nil;
[doc generateInputStream:&stream
length:&length
boundary:&boundary];
if (stream) {
NSString *url = [NSString stringWithFormat:@"%@?output=json&printerid=%@&contentType=image/png&title=MyApp&tag=my_app", CLOUD_PRINT_JOB_URL, printer];
NSLog(@"Printing to: %@", url);
NSMutableURLRequest *jobSubmitRequest;
NSTimeInterval timeout = 300.0;
jobSubmitRequest = [[NSMutableURLRequest alloc] initWithURL:[NSURL URLWithString:url]
cachePolicy:NSURLRequestReloadIgnoringCacheData
timeoutInterval:timeout];
NSString *httpHeaderContentTypeString = [NSString stringWithFormat:@"multipart/form-data; boundary=%@",boundary];
[jobSubmitRequest addValue:@"my_app" forHTTPHeaderField:@"X-CloudPrint-Proxy"];
[jobSubmitRequest addValue:httpHeaderContentTypeString forHTTPHeaderField:@"Content-Type"];
[jobSubmitRequest setHTTPMethod:@"POST"];
GTMHTTPFetcher* fetcher = [GTMHTTPFetcher fetcherWithRequest:jobSubmitRequest];
[fetcher setPostStream:stream];
[fetcher setAuthorizer:auth];
[fetcher beginFetchWithCompletionHandler:^(NSData *data, NSError *error) {
if (data) {
NSLog(@"data: %@", [NSString stringWithUTF8String:[data bytes]]);
}
if (error) {
NSLog(@"---- error: %@", error.localizedDescription);
} else if(completion){
completion();
}
}];
stream = nil;
fetcher = nil;
}
}
+(NSArray *) getPrinters{
return [[NSArray alloc] init];
}
@end